 Section number 30 of Gray's Anatomy Part 3. This is a LibriVox recording. All LibriVox recordings are in the public domain. For more information or to volunteer, please visit LibriVox.org. Recording by Miriam Coleman-Hipkins. The Popliteal Fossa. The Popliteal Artery. 6b. The Popliteal Fossa. Boundaries. The Popliteal Fossa, or space, is a lozenge-shaped space at the back of the knee joint. Laterally, it is bounded by the biceps femoris above and by the plentyrus and the lateral head of the gastroponemius below. Medally, it is limited by the semi-tendinosis and semi-membranosis above, and by the medial head of the gastroponemius below. The floor is formed by the Popliteal surface of the femur, the oblique Popliteal ligament of the knee joint, the upper end of the tibia, and the fascia covering the Popliteus. The fossa is covered in by the fasciolata. Contents. The Popliteal Fossa contains the Popliteal vessels, the tibial and the common perineal nerves, the termination of the small syphilis vein, the lower part of the posterior femoral cutaneous nerve, the articular branch from the obturator nerve, a few small lymph glands and a considerable quantity of fat. The tibial nerve descends through the middle of the fossa, lying under the deep fascia, and crossing the vessels posteriorly from the lateral to the medial side. The common perineal nerve descends on the lateral side of the upper part of the fossa, close to the tendon of the biceps femoris. On the floor of the fossa are the Popliteal vessels, the vein being superficial to the artery and united to it by dense areola tissue. The vein is a thick ward vessel and lies at first lateral to the artery and then crosses it posteriorly to gain its medial side below. Sometimes it is double, the artery lying between the two veins which are usually connected by short transverse branches. The articular branch from the obturator nerve descends upon the artery to the knee joint. The Popliteal lymph glands, six or seven in number, are embedded in the fat. One lies beneath the Popliteal fascia, near the termination of the external syphilis vein. Another between the Popliteal artery and the back of the knee joint, while the others are placed at the sides of the Popliteal vessel. Arising from the artery and passing off from it at right angles are its genicular branches. Let's see, the Popliteal artery, a Poplitea. The Popliteal artery is the continuation of the femoral and crosses through the Popliteal fossa. It extends from the opening in the abductive magnus at the junction of the middle and lower thirds of the thigh, downward and lateral wood to the intercontaloid fossa of the femur and then vertically downward to the lower border of the Popliteus where it divides into anterior and posterior tubular arteries. Relations. In front of the artery from above downward are the Popliteal surface of the femur, which is separated from the vessel via some fat. The back of the knee joint and the fascia covering the Popliteus. Behind, it is overlapped by the semi-membranosis above and is covered by the gastrocnemius and plantarus below. In the middle part of its course, the artery is separated from the enticement and fasciae via quantity of fat and is crossed from the lateral to the medial side by the tibial nerve and the Popliteal vein, the vein being between the nerve and the artery and closely adherent to the latter. On its lateral side above are the biceps femoris, the tibial nerve, the Popliteal vein and the lateral condor of the femur. Below, the plantarus and the lateral head of the gastrocnemius. On its medial side above are the semi-membranosis and the medial condor of the femur. Below the tibial nerve, the Popliteal vein and the medial head of the gastrocnemius. The relations of the Popliteal lymph glands to the artery are described above, peculiarities in point of division. Occasionally, the Popliteal artery divides into its terminal branches opposite the knee joint. The anterior tibial under these circumstances usually passes in front of the Popliteus. Unusual branches. The artery sometimes divides into the anterior tibial and perineal. The posterior tibial, being wanting or very small, occasionally it divides into three branches. The anterior and posterior tibial and perineal. Branches. The branches of the Popliteal artery are muscular, superior, sural, cutaneous, medial, superior, genicular, lateral, superior, genicular, middle, genicular, medial, inferior, genicular, lateral, inferior, genicular. The superior, muscular branches, two or three in number, arise from the upper part of the artery and are distributed to the lower parts of the adductor magnus and hamstring muscles, inastomosing with the terminal part of the profunda femoris. The sural arteries A.A. suralis inferior muscular arteries are two large branches which are distributed to the gastrocnemius, soleus and plantarus. They arise from the Popliteal artery opposite the knee joint. The cutaneous branches arise either from the Popliteal artery or from some of its branches. They descend between the two heads of the gastrocnemius and piercing the deep fascia are distributed to the skin of the back of the leg. One branch usually accompanies the small syphilis vein. The superior genicular arteries A.A. genus superioris superior articular arteries, two in number, arise one on either side of the Popliteal and wind round the femur immediately above its condom to the front of the knee joint. The medial superior genicular runs in front of the semi-membranosis and semi-tendinosis, above the medial head of the gastrocnemius and passes beneath the tendon of the adductor magnus. It divides into two branches, one of which supplies the vastus medialis, anastomosing with the highest genicular and medial inferior genicular arteries. The other ramifies close to the surface of the femur, supplying it and the knee joint, and anastomosing with the lateral superior genicular artery. The medial superior genicular artery is frequently of small size, a condition which is associated with an increase in the size of the highest genicular. The lateral superior genicular passes above the lateral condom of the femur beneath the tendon of the biceps femoris and divides into a superficial and a deep branch. The superficial branch supplies the vastus lateralis and anastomoses with the descending branch of the lateral femal circumflex and the lateral inferior genicular arteries. The deep branch supplies the lower part of the femur and knee joint and forms an anastomotic arch across the front of the bone with the highest genicular and the medial inferior genicular arteries. The middle genicular artery, a genu media, a sargos articular artery, is a small branch arising opposite the back of the knee joint. It pierces the oblique popliteal ligament and supplies the ligaments and synovial membrane in the interior of the articulation. The inferior genicular arteries, a genu inferioris, inferior articular arteries, to a number, arrives from the popliteal beneath the gastrocnemius. The medial inferior genicular first descends along the upper margins of the popliteus to which it gives branches. It then passes below the medial condom of the tibia beneath the tibial collateral ligament at the anterior border of which it ascends to the front and medial side of the joint. To supply the upper end of the tibia and the articulation of the knee, anastomosing with the lateral inferior and medial superior genicular arteries. The lateral inferior genicular runs lateral wood along the head of the fibula to the front of the knee joint, passing in its course beneath the lateral head of the gastrocnemius, the fibular collateral ligament and the tendon of the biceps femoris. It ends by dividing into branches which anastomose with the medial inferior and lateral superior genicular arteries and with the interior recurrent tibial artery. The anastomosis around the knee joint, around and above the patellar and on the contiguous ends of the femur and tibia is an intricate network of vessels forming a superficial and a deep plexus. The superficial plexus is situated between the fascia and skin around the patellar and forms three well-defined arches, one above the upper border of the patellar and the loose connective tissue over the quadriceps femoris. The other two below the level of the patellar are situated in the fat behind the ligamentum patelli. The deep plexus which forms a close network of vessels lies on the lower end of the femur and upper end of the tibia around the articular surfaces and sends numerous offsets into the interior of the joint. The arteries which form this plexus are the two medial and the two lateral genicular branches of the popliteal, the highest genicular, the descending branch of the lateral femoral circumflex and the interior recurrent tibial. End of section number 30, Recording by Marianne Coleman-Hitkins, www.thisvoice4u.com Section 31 of Grey's Anatomy, Part 3 This is a LibriVox recording. All LibriVox recordings are in the public domain. For more information or to volunteer, please visit LibriVox.org. Anatomy of the human body, Part 3 by Henry Gray, The anterior tibial artery, Arteria tibialis anterior. The anterior tibial artery commences at the bifurcation of the popliteal at the lower border of the popliteus passes forward between the two heads of the tibialis posterior and through the aperture above the upper border of the interosseous membrane to the deep part of the front of the leg. It here lies close to the medial side of the neck of the fibula. It then descends on the anterior surface of the interosseous membrane, gradually approaching the tibia. At the lower part of the leg it lies on this bone and then on the front of the ankle joint, where it is more superficial and becomes the dorsalis pedis. Relations In the upper two-thirds of its extent the anterior tibial artery rests upon the interosseous membrane, in the lower third upon the front of the tibia and the anterior ligament of the ankle joint. In the upper third of its course it lies between the tibialis anterior and the extensor digitorum longus. In the middle third between the tibialis anterior and extensor hallusis longus. At the ankle it is crossed from the lateral to the medial side by the tendon of the extensor hallusis longus and lies between it and the first tendon of the extensor digitorum longus. It is covered in the upper two-thirds of its course by the muscles which lie on either side of it and by the deep fascia. In the lower third by the integument and fascia and the transverse and cruciate crural ligaments. The anterior tibial artery is accompanied by a pair of venae cometantis which lie one on either side of the artery. The deep peroneal nerve coursing through the lateral side of the neck of the fibula comes into relation with the lateral side of the artery shortly after it has reached the front of the leg. About the middle of the leg the nerve is in front of the artery. At the lower part it is generally again on the lateral side. peculiarities in size. This vessel may be diminished in size may be deficient to a greater or less extent or may be entirely wanting its place being supplied by perforating branches from the posterior tibial or by the perforating branch of the peroneal artery. Of course the artery occasionally deviates toward the fibular side of the leg regaining its usual position at the front of the ankle. In rare instances the vessel has been found to approach the surface in the middle of the leg being covered merely by the integument and fascia below that point. Branches. The branches of the anterior tibial artery are posterior tibial recurrent, fibular anterior tibial recurrent, muscular anterior medial mullular, anterior lateral mullular. The posterior tibial recurrent artery arteria recurrent tibialis posterior. An inconstant branch is given off from the anterior tibial before that vessel passes through the interosseous space. It essence in front of the popliteus which it supplies and anastomoses with the inferior genicular branches of the popliteal artery giving an offset to the tibio fibular joint. The fibular artery is sometimes derived from the anterior tibial, sometimes from the posterior tibial. It passes lateralward around the neck of the fibula through the soleus which it supplies and ends in the substance of the peroneus longus. The anterior tibial recurrent artery, arteria recurrent tibialis anterior, arises from the anterior tibial as soon as that vessel has passed through the interosseous space. It essence in the tibialis anterior, ramifies on the front and side of the knee joint and assists in the formation of the patellar plexus by anastomosing with the genicular branches of the popliteal and with the highest genicular artery. The muscular branches where my muscularis are numerous, they are distributed to the muscles which lie on other side of the vessel, some piercing the deep fascia to supply the integument, others passing through the interosseous membrane and anastomosing with branches of the posterior tibial and peroneal arteries. The anterior medial mullular artery, arteria mullularis anterior medialis internal mullular artery arises about 5 centimeters above the ankle joint and passes behind the tendons of the extensor hallusis longus and tibialis anterior to the medial side of the ankle upon which it ramifies anastomosing with branches of the posterior tibial and medial plantar arteries and with the medial calcaneal from the posterior tibial. The anterior lateral mullular artery, arteria mullularis anterior lateralis external mullular artery passes beneath the tendons of the extensor digitorum longus and peroneus tercius and supplies the lateral side of the ankle anastomosing with the perforating branch of the peroneal artery and with ascending twigs from the lateral tarsal artery. The arteries around the ankle joint anastomose freely with one another and form networks below the corresponding mulluli. The medial mullular network is formed by the anterior medial mullular branch of the anterior tibial, the medial tarsal branches of the dorsalis pedis, the posterior medial mullular and medial calcaneal branches of the posterior tibial and branches from the medial plantar artery. The lateral mullular network is formed by the anterior lateral mullular branch of the anterior tibial, the lateral tarsal branch of the dorsalis pedis, the perforating and the lateral calcaneal branches of the peroneal and twigs from the lateral plantar artery, the arteria dorsalis pedis, dorsalis pedis artery. The arteria dorsalis pedis, the continuation of the anterior tibial passes forward from the ankle joint along the tibial side of the dorsum of the foot to the proximal part of the first inter metatarsal space where it divides into two branches, the first dorsal metatarsal and the deep plantar. Relations. This vessel, in its course forward, rests upon the front of the articulate capsule of the ankle joint, the talus, navicular and second cuneiform bones and the ligaments connecting them, being covered by the integument, fascia and cruciate ligament and crossed near its termination by the first tendon of the extensor digitorum brevis. On its tibial side is the tendon of the extensor halusus longus. On its fibular side, the first tendon of the extensor digitorum longus and the termination of the deep peroneal nerve. It is accompanied by two veins, peculiarities in size. The dorsal artery of the foot may be larger than usual to compensate for a deficient plantar artery or its terminal branches to the toes may be absent, the toes then being supplied by the medial plantar or its place may be taken altogether by a large perforating branch of the peroneal artery. Position. This artery frequently curves lateral verte, lying lateral to the line between the middle of the ankle and the back part of the first interrosia space. Branches. The branches of the arteria dorsalis pedis are lateral tarsal, medial tarsal or cuate, first dorsal metatarsal, deep plantar. The lateral tarsal artery arteria torsia lateralis, tarsal artery arises from the dorsalis pedis as that vessel crosses the navicular bone. It passes in an arched direction lateral verte, lying upon the tarsal bones and covered by the extensor digitorum brevis. It supplies this muscle and the articulations of the tarsis and anastomosis with branches of the archivet anterior lateral mullular and lateral plantar arteries and with the perforating branch of the peroneal artery. The medial tarsal arteries arteria torsia medialis are two or three small branches which ramify on the medial border of the foot and join the medial mullular network. The archivet artery, arteria archiveta, metatarsal artery arises a little anterior to the lateral tarsal artery. It passes lateral verte over the basis of the metatarsal bones beneath the tendons of the extensor digitorum brevis, its direction being influenced by its point of origin and it anastomosis with the lateral tarsal and lateral plantar arteries. This vessel gives off the second, third and fourth dorsal metatarsal arteries which run forward upon the corresponding interrosi dorsalis. In the clefts between the toes, each divides into two dorsal digital branches for the adjoining toes. At the proximal parts of the interrosia spaces, these vessels receive the posterior perforating branches from the plantar arch and at the distal parts of the spaces, they are joined by the anterior perforating branches from the plantar metatarsal arteries. The fourth dorsal metatarsal artery gives off a branch which supplies the lateral side of the fifth toe. The first dorsal metatarsal artery arteria dorsalis hallusis runs forward on the first interrosia dorsalis and at the cleft between the first and second toes divides into two branches, one of which passes between the tendon of the extensor hallusis longus and is distributed to the medial border of the great toe. The other bifurcates to supply the adjoining sides of the great and second toes. The deep plantar artery ramus plantaris profundus communicating artery descends into the sole of the foot between the two heads of the first interrosius dorsalis and unites with the termination of the lateral plantar artery to complete the plantar arch. It sends a branch along the medial side of the great toe and is continued forward along the first interrosius space at the first plantar metatarsal artery which bifurcates for the supply of the adjacent sides of the great and second toes. End of section 31 section 32 of Grey's Anatomy part 3. This is a LibriVox recording. All LibriVox recordings are in the public domain. For more information or to volunteer please visit LibriVox.org. Anatomy of the human body part 3 by Henry Grey. The posterior tibial artery. Arteria tibialis posterior. The posterior tibial artery begins at the lower border of the popliteus opposite the interval between the tibia and fibula. It extends obliquely downward and as it descends it approaches the tibial side of the leg lying behind the tibia and in the lower part of its course is situated midway between the medial mulliolis and the medial process of the calcaneal tuberosity. Here it divides beneath the origin of the adductor halusus into the medial and lateral plantar arteries. Relations. The posterior tibial artery lies successively upon the tibialis posterior, the flexor digitorum longus, the tibia and the back of the ankle joint. It is covered by the deep transverse fascia of the leg which separates it above from the gastrocnemius and tholius. At its termination it is covered by the abductor halusus. In the lower third of the leg where it is more superficial it is covered only by the integument and fascia and runs parallel with the medial border of the tendocalcaneus. It is accompanied by two veins and by the tibial nerve which lies at first to the medial side of the artery but soon crosses it posteriorly and is in the greater part of its course on its lateral side. Behind the medial mulliolis the tendons, blood vessels and nerve are arranged under cover of the lacenate ligament in the following order from the medial to the lateral side. 1. The tendons of the tibialis posterior and flexor digitorum longus lying in the same groove behind the mulliolis the former being the more medial. Next is the posterior tibial artery with the vein on either side of it and lateral to the vessels is the tibial nerve. About 1.25 centimeter nearer the heel is the tendon of the flexor halusus longus. Peculiarities in size. The posterior tibial is not infrequently smaller than usual or absent its place being supplied by a large perineal artery which either joins the small posterior tibial artery or continues alone to the sole of the foot. 2. Branches. The branches of the posterior tibial artery are perineal, nutrient, muscular, posterior medial mullular, communicating, medial calcaneal. The perineal artery arteria peroneia is deeply seated on the back of the fibular side of the leg. It arises from the posterior tibial about 2.5 centimeter below the lower border of the popliteus passes obliquely toward the fibula and then descends along the medial side of that bone contained in a fibrous canal between the tibialis posterior and the flexor halusus longus or in the substance of the lateral muzzle. It then runs behind the tibiofibular cindesmosis and divides into lateral calcaneal branches which ramify on the lateral and posterior surfaces of the calcaneus. It is covered in the upper part of its course by the soleus and deep transverse fascia of the leg below by the flexor halusus longus. Peculiarities in origin. The perineal artery may arise 7 to 8 centimeter below the popliteus or from the posterior tibial high up or even from the popliteal. Its size is more frequently increased than diminished and then it either reinforces the posterior tibial by its junction with it or altogether takes the place of the posterior tibial in the lower part of the leg and foot. The lateral vessel only existing as a short muscular branch. In those rare cases where the perineal artery is smaller than usual a branch from the posterior tibial supplies its place and a branch from the anterior tibial compensates for the diminished anterior perineal artery. In one case the perineal artery was entirely wanting. Branches. The branches of the perineal are muscular, nutrient, perforating, communicating, lateral calcaneal. Muscular branches. The perineal artery in its course gives off branches to the soleus tibialis posterior flexor halusus longus and peronii. The nutrient artery arteria nutricia fibulae supplies the fibula and is directed downward. The perforating branch ramus perforants anterior perineal artery pierces the interosseous membrane about 5 centimeter above the lateral mullulus to reach the front of the leg where it anastomosis with the anterior lateral mullular. It then passes down in front of the tibiofibular cindesmosis, gives branches to the tarsus and anastomosis with the lateral tarsal. The perforating branch is sometimes enlarged and takes the place of the dorsalis pedis artery. The communicating branch ramus communicans is given off from the perineal about 2.5 centimeter from its lower end and joins the communicating branch of the posterior tibial. The lateral calcaneal ramus calcaneus lateralis, external calcaneal, are the terminal branches of the perineal artery. They pass to the lateral side of the heel and communicate with the lateral mullular and on the back of the heel with the medial calcaneal arteries. The nutrient artery, arteria nutricia tibia, of the tibia arises from the posterior tibial near its origin and after supplying a few muscular branches enters the nutrient canal of the bone which it traverses obliquely from above downward. This is the largest nutrient artery of bone in the body. The muscular branches of the posterior tibial are distributed to the soleus and deep muscles along the back of the leg. The posterior medial mullular artery, arteria mullularis posterior medialis internal mullular artery is a small branch which winds around the tibial mullulus and ends in the medial mullular network. The communicating branch ramus communicans runs transversely along the back of the tibia about 5 centimeter above its lower end beneath the flexor hallusus longus and joins the communicating branch of the perineal. The medial calcaneal ramai calcanei medialis internal calcaneal are several large arteries which arise from the posterior tibial just before its division. They pierce the laccenate ligament and are distributed to the fat and integument behind the tendo calcaneus and about the heel and to the muscles on the tibial side of the sole anastomosing with the perineal and medial mullular and on the back of the heel with the lateral calcaneal arteries. The medial plantar artery, arteria plantaris medialis internal plantar artery much smaller than the lateral passes forward along the medial side of the foot. It is at first situated above the abductor hallusus and then between it and the flexor digitorum brevis both of which it supplies. At the base of the first metatarsal bone where it is much diminished in size it passes along the medial border of the first toe anastomosing with the first dorsal metatarsal artery. Small superficial digital branches accompany the digital branches of the medial plantar nerve and join the plantar metatarsal arteries of the first three spaces. The lateral plantar artery, arteria plantaris lateralis external plantar artery much larger than the medial passes obliquely lateralward and forward to the base of the fifth metatarsal bone. It then turns medialward to the interval between the bases of the first and second metatarsal bones where it unites with the deep plantar branch of the dorsalis pedis artery thus completing the plantar arch. As this artery passes lateralward it is first placed between the calcaneus and abductor hallusus and then between the flexor digitorum brevis and quadratus plantae. As it runs forward to the base of the little toe it lies more superficially between the flexor digitorum brevis and abductor digitii quintii covered by the plantar aponeurosis and integument. The remaining portion of the vessel is deeply situated it extends from the base of the fifth metatarsal bone to the proximal part of the first interosseous space and forms the plantar arch. It is convex forward lies below the bases of the second third and fourth metatarsal bones and the corresponding interossei and upon the oblique part of the adductor hallusus. Branches. The plantar arch besides distributing numerous branches to the mussels, integument and fasciae in the sole gives off the following branches perforating plantar metatarsal. The perforating branches ramai perforantis are three in number they are sent through the proximal parts of the second third and fourth interosseous spaces between the heads of the interossei dorsalis and anastomose with the dorsal metatarsal arteries. The plantar metatarsal arteries arteria metatarsae plantaris digital branches are four in number and run forward between the metatarsal bones and in contact with the interossei. Each divides into a pair of plantar digital arteries which supply the adjacent sides of the toes. Near their points of division each sends upward an anterior perforating branch to join the corresponding dorsal metatarsal artery. The first plantar metatarsal artery arteria princeps hallusus springs from the junction between the lateral plantar and deep plantar arteries and sends the digital branch to the medial side of the first toe. The digital branch for the lateral side of the fifth toe arrives from the lateral plantar artery near the base of the fifth metatarsal bone. End of Section 32. Section 33 of Gray's Anatomy Part 3. This is a LibriVox recording. All LibriVox recordings are in the public domain. For more information or to volunteer, please visit LibriVox.org. Anatomy of the Human Body Part 3 by Henry Gray The Vains Introduction The veins convey the blood from the capillaries of the different parts of the body to the heart. They consist of two distinct sets of vessels, the pulmonary and systemic. The pulmonary veins, unlike other veins, contain arterial blood, which they return from the lungs to the left atrium of the heart. The systemic veins return the venous blood from the body generally to the right atrium of the heart. The portal vein and appendage to the systemic venous system is confined to the abdominal cavity and returns the venous blood from the spleen and the viscera of digestion to the liver. This vessel ramifies in the substance of the liver and there breaks up into a minute network of capillary-like vessels from which the blood is conveyed by the hepatic veins to the inferior vena cava. The veins commence by minute plexuses which receive the blood from the capillaries. The branches arising from these plexuses unite together into trunks and these, in their passage toward the heart, constantly increase in size as they receive tributaries or join other veins. The veins are larger and altogether more numerous than the arteries, hence the entire capacity of the venous system is much greater than that of the arterial. The capacity of the pulmonary veins, however, only slightly exceeds that of the pulmonary arteries. The veins are cylindrical like the arteries, their walls, however, are thin and they collapse when the vessels are empty and the uniformity of their surfaces is interrupted at intervals by slight constrictions which indicate the existence of valves in their interior. They communicate very freely with one another especially in certain regions of the body and these communications exist between the larger trunks as well as between the smaller branches. Thus, between the venous sinuses of the cranium and between the veins of the neck where obstruction would be attended with imminent danger to the cerebral venous system, large and frequent anastomoses are found. The same free communication exists between the veins throughout the whole extent of the vertebral canal and between the veins composing the various venous plexuses in the abdomen and pelvis, for example, the spermatic, uterine, vesicle, and pudental. The systemic venous channels are subdivided into three sets namely superficial and deep veins and venous sinuses. The superficial veins, cutaneous veins, are found between the layers of the superficial fascia immediately beneath the skin. They return the blood from these structures and communicate with the deep veins by perforating the deep fascia. The deep veins accompany the arteries and are usually enclosed in the same sheaths with these vessels. With the smaller arteries as the radial ulnar brachial, tibial, peroneal, they exist generally in pairs, one lying on each side of the vessel and are called venicomatantes. The larger arteries such as the axillary, subclavian, popliteal, and femoral have usually only one accompanying vein. In certain organs of the body, however, the deep veins do not accompany the arteries. For instance, the veins in the skull and vertebral canal, the hepatic veins in the liver, and the larger veins returning blood from the bones. Venous sinuses are found only in the interior of the skull and consist of canals formed by the separation of the two layers of the duramator. Their outer coat consists of fibrous tissue. Their inner of an endothelial layer, continuous with the lining membrane of the veins. End of section 33. Section 34 of Gray's Anatomy Part 3. This is the LibriVox recording. All LibriVox recordings are in the public domain. For more information or to volunteer, please visit LibriVox.org. Anatomy of the Human Body Part 3 by Henry Gray. Pulmonary veins, systemic veins, and veins of the heart. Two, the pulmonary veins. Vayna pulmar nalis. The pulmonary veins return the arterialized blood from the lungs to the left atrium of the heart. They are four in number, two from each lung, and a destitute of valves. They commence in a capillary network upon the walls of the air sacs, where they are continuous with the capillary ramifications of the pulmonary artery, and join it together for one vessel for each lobule. These vessels, uniting successively, form a single trunk for each lobe, three for the right and two for the left lung. The vein from the middle lobe of the right lung generally unites with that from the upper lobe, so that ultimately two trunks from each lung are formed. They perforate the fibrous layer of the pericardium and open separately into the upper and back parts of the left atrium. Occasionally, the three veins on the right side remain separate. Not infrequently, the two left pulmonary veins end by a common opening. At the root of the lung, the superior pulmonary vein lies in front of, and a little below, the pulmonary artery. The inferior is situated at the lowest part of the heartless of the lung, and on a plane posterior to the upper vein. Behind the pulmonary artery is the bronchus. Within the pericardium, their anterior surfaces are invested by the serous layer of this membrane. The right pulmonary veins pass behind the right atrium and superior vena cava, the left in front of the descending thoracic aorta. Three, the systemic veins. The systemic veins may be arranged into three groups, the veins of the heart, the veins of the upper extremities, head, neck and thorax, which end in the superior vena cava, the veins of the lower extremities, abdomen and pelvis, which end in the inferior vena cava, the veins of the heart, coronary sinus, sinus coronaris, vv cordus. Most of the veins of the heart open into the coronary sinus. This is a wide venous channel about 2.25 centimetres in length, situated in the posterior part of the coronary sulcus, and covered by muscular fibres from the left atrium. It ends in the right atrium between the openings of the inferior vena cava and the atrioventricular aperture. It's orifice being guarded by a semi-lunar valve, the valve of the coronary sinus, valve of the biceous. Tributaries. Its tributaries are the great small and middle cardiac veins, the posterior vein of the left ventricle and the oblique vein of the left atrium, all of which, except the last, are provided with valves at the orifices. One, the great cardiac vein, vein cordus magna, left coronary vein, begins at the apex of the heart and descends along the anterior longitudinal sulcus to the base of the ventricles. It then curves to the left in the coronary sulcus, opens into the left extremity of the coronary sinus, and reaching the back of the heart opens into the left extremity of the coronary sinus. It receives tributaries from the left atrium and from both ventricles. One, the left marginal vein, is of considerable size and ascends along the left margin of the heart. Two, the small cardiac vein, vein cordus pave, right coronary vein, runs in the coronary sulcus between the right atrium and ventricle, and opens into the right extremity of the coronary sinus. It receives blood from the back of the right atrium and ventricle. The right marginal vein ascends along the right margin of the heart and joins it in the coronary sulcus, or opens directly into the right atrium. Three, the middle cardiac vein, vein cordus media, commences at the apex of the heart, ascends to the posterior longitudinal sulcus, and ends in the coronary sinus near its right extremity. Four, the posterior vein of the left ventricle, venous posterior ventricular sinestro, runs on the diaphragmatic surface of the left ventricle to the coronary sinus, but may end in the great cardiac vein. Five, the oblique vein of the left atrium, venous obliqueis antheris sinestro, oblique vein of martial, is a small vessel which descends oblique on the back of the left atrium and ends in the coronary sinus near its left extremity. It is continuous above with the ligament of the left vena cava, lig vena carves sinestro vestigial fold of martial, and the two structures from the remnant of the left caverian duct. The following cardiac veins do not end in the coronary sinus. One, the anterior cardiac veins, comprising three or four small vessels which collect blood from the front of the right ventricle and open into the right atrium. The right marginal vein frequently opens into the right atrium, and is therefore sometimes regarded as belonging to this group. Two, the smallest cardiac veins, veins of the bicius, consist of a number of minute veins which arise in the muscular wall of the heart. The majority open into the atria, but a few end in the ventricles. End of Section 34. Section 35 of Gray's Anatomy Part 3 This is a LibriVox recording. All LibriVox recordings are in the public domain. For more information or to volunteer, please visit LibriVox.org. Recording by Bologna Times. Anatomy of the Human Body Part 3 by Henry Gray Vans of Head and Neck Vans of Exterior of Head and Face 3b. The Vans of the Head and Neck The Vans of the Head and Neck may be subdivided into three groups. 1. The Vans of the Exterior of the Head and Face 2. The Vans of the Neck 3. The Diploic Vans The Vans of the Brain and the Venous Sinuses of the Duramatter The Vans of the Exterior of the Head and Face are Frontal, Superficial, Temporal Superorbital, Internal, Maxillary Angular, Posterior Facial Interior Facial, Posterior Arricular Oxypital. The Front Vane, Venous Frontalis Begins in the Forehead and a Venous Plexus which communicates with the frontal branches of the Superficial, Temporal Vane. The Vans converge to form a single trunk which runs downward near the middle line of the forehead, parallel with the Vane of the opposite side. The two Vans are joined at the root of the nose by a transverse branch called the nasal arch, which receives some small veins from the dorsum of the nose. At the root of the nose the Vans diverge and each at the medial angle of the orbit joins the Supraorbital Vane to form the Angular Vane. Occasionally the Frontal Vanes join to form a single trunk, which bifurcates at the root of the nose into the two Angular Vanes. The Supraorbital Vane, Venous Supraorbitalis begins on the forehead where it communicates with the frontal branch of the Supraficial, Temporal Vane. It runs downward, superficial, to the Frontalis Muscle and joins the Frontal Vane at the medial angle of the orbit to form the Angular Vane. Previous to its junction with the Frontal Vane, it sends through the Supraorbital Notch into the orbit a branch which communicates with the Ophthalmic Vane. As this vessel passes through the Notch, it receives the Frontal Diploic Vane through a Foreman at the bottom of the Notch. The Angular Vane, Venous Angularis formed by the junction of the Frontal and Supraorbital Vanes runs obliquely downward on the side of the root of the nose to the level of the lower margin of the orbit where it becomes the anterior Facial Vane. It receives the veins of the Aela Nazae and communicates with the Superior Ophthalmic Vane through the Nasofrontal Vane, thus establishing an important Anastomosis between the Anterior Facial Vane and the Cavernous Sinus. The Anterior Facial Vane, Venous Facialis Anterior Facial Vane, commences at the side of the root of the nose and is a direct continuation of the Angular Vane. It lies behind the external Maxillary Facial artery and follows a less tortuous course. It runs obliquely downward and backward beneath the zygomaticus and zygomatic head of the quadratus labi superioris. Descends along the anterior border and then on the superficial surface of the masseter, crosses over the body of the mandible and passes obliquely backward beneath the platissima and cervical fascia, superficial to the submaxillary gland, the digastricus and stylo hyoidius. It unites with the posterior Facial Vane to form the common Facial Vane, which crosses the external carotid artery and enters the internal jugular vein at a variable point beyond the hyoid bone. From near its termination, a communicating branch often runs down the anterior border of the sternocleidomestoidus to join the lower part of the anterior jugular vein. The Facial Vane has no valves and its walls are not so flaccid as most superficial veins. Trivitaries The anterior Facial Vane receives a branch of considerable size, the deep Facial Vane, from the pterygoid venous plexus. It is also joined by the superior and inferior palpabrol, the superior and inferior labial, the buccinator and the masseteric veins. Below the mandible it receives the submental palatine and submaxillary veins, and generally the vena comitants of the hypoglossal nerve. The superficial temporal vein, venous temporalis superficialis, begins on the side and vertex of the skull and a plexus, which communicates with the frontal and superorbital veins, with the corresponding vein on the opposite side and with the posterior auricular and occipital veins. From this network frontal and parietal branches arise and unite above the zygomatic arch to form the trunk of the vein, which is joined in the situation by the middle temporal vein from the substance of the temporalis. It then crosses the posterior root of the zygomatic arch, enters the substance of the parotid gland, and unites with the internal maxillary vein to form the posterior facial vein, tributaries. The superficial temporal vein receives in its course some parotid veins, articular veins from the temporal mandibular joint, anterior auricular veins from the auricular and the transverse facial from the side of the face. The middle temporal vein receives the orbital vein, which is formed by some lateral palpabral branches and passes backward between the layers of the temporal fascia to join the superficial temporal vein. The plexus pterygoidus is of considerable size and is situated between the temporalis and pterygoidus externus and partly between the two pterygoidae. It receives tributaries corresponding with the branches of the internal maxillary artery. Thus it receives the sphenopalatine, the middle meningeal, the deep temporal, the pterygoid, mastotaric, bucinator, alveolar, and some palatine veins, and a branch which communicates with the ophthalmic vein through the inferior orbital fissure. This plexus communicates freely with the anterior facial vein. It also communicates with the cavernous sinus by branches through the foramen vesselae, foramen oval, and foramen lacerum. The internal maxillary vein, venus maxilaris enterna, is a short trunk which accompanies the first part of the internal maxillary artery. It is formed by a confluence of the veins of the pterygoid plexus and passes backward between the sphenomendibular ligament and the neck of the mandible, and unites with the temporal vein to form the posterior facial vein. The posterior facial vein, venus fissialis posterior, temporal maxillary vein, formed by the union of the superficial temporal and internal maxillary veins, descends in the substance of the peritide gland, superficial to the external carotid artery, but beneath the facial nerve, between the ramus of the mandible and the sternocleidomastoidius muscle. It divides into two branches, an anterior, which passes forward and unites with the anterior facial vein to form the common facial vein, and a posterior, which is joined by the posterior auricular vein and becomes the external jugular vein. The posterior auricular vein, venus auricularis posterior, begins upon the side of the head in a plexus, which communicates with the tributaries of the occipital and superficial temporal veins. It descends behind the auricular and joins the posterior division of the posterior facial vein to form the external jugular. It received the stylomastoid vein and some tributaries from the cranial surface of the auricular. The occipital vein, venus occipitalis, begins in a plexus at the back of the vertex of the skull. From the plexus emerges a single vessel, which pierces the cranial attachment of the trapezius and dipping into the suboccipital triangle joins the deep cervical and vertebral veins. Occasionally it follows the course of the occipital artery and ends in the internal jugular. In other instances it joins the posterior auricular and through it opens into the external jugular. The parietal emissary vein connects it with the superior sagittal sinus and as it passes across the mastoid portion of the temporal bone it receives the mastoid emissary vein which connects it with the transverse sinus. The occipital diploic vein sometimes joins it. This is a LubriVox recording. All LubriVox recordings are in the public domain. For more information or to volunteer please visit LubriVox.org Recorded by Laurie Ann Walden Anatomy of the Human Body Part 3 by Henry Gray The Veins of the Neck The veins of the neck which return the blood from the head and face are external jugular, posterior external jugular, anterior jugular, internal jugular, vertebral. The external jugular vein, vena jugularis externa, receives the greater part of the blood from the exterior of the cranium and the deep parts of the face being formed by the junction of the posterior division of the posterior facial with the posterior auricular vein. It commences in the substance of the parotid gland on a level with the angle of the mandible and runs perpendicularly down the neck in the direction of a line drawn from the angle of the mandible to the middle of the clavicle at the posterior border of the sternocleidomastoidius. In its course it crosses the sternocleidomastoidius obliquely and in the subclavian triangle perforates the deep fascia and ends in the subclavian vein lateral to or in front of the scolinas anterior. It is separated from the sternocleidomastoidius by the investing layer of the deep cervical fascia and is covered by the platysma, the superficial fascia, and the integument. It crosses the cutaneous cervical nerve and its upper half runs parallel with the great auricular nerve. The external jugular vein varies in size, bearing an inverse proportion to the other veins of the neck. It is occasionally double. It is provided with two pairs of valves, the lower pair being placed at its entrance into the subclavian vein, the upper in most cases about four centimeters above the clavicle. The portion of the vein between the two sets of valves is often dilated and is termed the sinus. These valves do not prevent the regurgitation of the blood or the passage of injection from below upward. Tributaries. This vein receives the occipital occasionally, the posterior external jugular, and near its termination, the transverse cervical, transverse scapular, and anterior jugular veins. In the substance of the parotid, a large branch of communication from the internal jugular joins it. The posterior external jugular vein, Vena jugularis posterior, begins in the occipital region and returns the blood from the skin and superficial muscles in the upper and back part of the neck, lying between the spleenius and trapezius. It runs down the back part of the neck and opens into the external jugular vein just below the middle of its course. The anterior jugular vein, Vena jugularis anterior, begins near the hyoid bone by the confluence of several superficial veins from the submaxillary region. It descends between the median line and the anterior border of the sternocleidomastoidius, and at the lower part of the neck, passes beneath that muscle to open into the termination of the external jugular, or in some instances, into the subclavian vein. It varies considerably in size, bearing usually an inverse proportion to the external jugular. Most frequently, there are two anterior jugulars, a right and left, but sometimes only one. Its tributaries are some laryngeal veins, and occasionally a small thyroid vein. Just above the sternum, the two anterior jugular veins communicate by a transverse trunk, the venus jugular arch, which receive tributaries from the inferior thyroid veins. Each also communicates with the internal jugular. There are no valves in this vein. The internal jugular vein, Vena jugularis interna, collects the blood from the brain, from the superficial parts of the face, and from the neck. It is directly continuous with the transverse sinus, and begins in the posterior compartment of the jugular foramen at the base of the skull. At its origin, it is somewhat dilated, and this dilatation is called the superior bulb. It runs down the side of the neck in a vertical direction, lying at first lateral to the internal carotid artery, and then lateral to the common carotid, and at the root of the neck, unites with the subclavian vein to form the inominate vein. A little above its termination is a second dilatation, the inferior bulb. Above, it lies upon the rectus capitis lateralis, behind the internal carotid artery and the nerves passing through the jugular foramen. Lower down, the vein and artery lie upon the same plane, the glossopharyngeal and hypoglossal nerves passing forward between them. The vagus descends between and behind the vein and the artery in the same sheath, and the accessory runs obliquely backward, superficial or deep to the vein. At the root of the neck, the right internal jugular vein is placed at a little distance from the common carotid artery, and crosses the first part of the subclavian artery. While the left internal jugular vein usually overlaps the common carotid artery. The left vein is generally smaller than the right, and each contains a pair of valves, which are placed about 2.5 centimeters above the termination of the vessel. Tributaries. This vein receives in its course the inferior petrosal sinus, the common facial, lingual, pharyngeal, superior and middle thyroid veins, and sometimes the occipital. The thoracic duct on the left side and the right lymphatic duct on the right side open into the angle of union of the internal jugular and subclavian veins. The inferior petrosal sinus, sinus-petrosus inferior, leaves the skull through the anterior part of the jugular foramen, and joins the superior bulb of the internal jugular vein. The lingual veins, vena lingualis, begin on the dorsum, sides and under surface of the tongue, and passing backward along the course of the lingual artery end in the internal jugular vein. The vena cometans of the hypoglossal nerve, ranine vein, a branch of considerable size, begins below the tip of the tongue and may join the lingual. Generally, however, it passes backward on the hyoglossus and joins the common facial. The pharyngeal veins, vena pharyngeae, begin in the pharyngeal plexus on the outer surface of the pharynx, and after receiving some posterior meningeal veins and the veins of the pterygoid canal end in the internal jugular. They occasionally open into the facial, lingual, or superior thyroid vein. The superior thyroid vein, vena thyroidia superioris, begins in the substance and on the surface of the thyroid gland, by tributaries corresponding with the branches of the superior thyroid artery, and ends in the upper part of the internal jugular vein. It receives the superior laryngeal and cricothyroid veins. The middle thyroid vein collects the blood from the lower part of the thyroid gland, and after being joined by some veins from the larynx and trachea, ends in the lower part of the internal jugular vein. The common facial and occipital veins have been described. The vertebral vein, vena vertebralis, is formed in the suboccipital triangle from numerous small tributaries which spring from the internal vertebral venous plexuses, an issue from the vertebral canal above the posterior arch of the atlas. They unite with small veins from the deep muscles at the upper part of the back of the neck, and form a vessel which enters the foramen in the transverse process of the atlas, and descends, forming a dense plexus around the vertebral artery, in the canal formed by the foramina transversaria of the cervical vertebrae. This plexus ends in a single trunk which emerges from the foramen transversarium of the sixth cervical vertebra, and opens at the root of the neck into the back part of the inominate vein near its origin, its mouth being guarded by a pair of valves. On the right side it crosses the first part of the subclavian artery. Tributaries. The vertebral vein communicates with the transverse sinus by a vein which passes through the condyloid canal when that canal exists. It receives branches from the occipital vein and from the pre-vertebral muscles, from the internal and external vertebral venous plexuses, from the anterior vertebral and the deep cervical veins. Close to its termination it is sometimes joined by the first intercostal vein. The anterior vertebral vein commences in a plexus around the transverse processes of the upper cervical vertebrae, descends in company with the ascending cervical artery between the scelenus anterior and longest capitis muscles, and opens into the terminal part of the vertebral vein. The deep cervical vein, venous cervicalis profundus posterior vertebral, or posterior deep cervical vein, accompanies its artery between the semi-spinales, capitis, and coli. It begins in the suboccipital region by communicating branches from the occipital vein and by small veins from the deep muscles at the back of the neck. It receives tributaries from the plexuses around the spinous processes of the cervical vertebrae and terminates in the lower part of the vertebral vein. In the section 36. Section 37 of Grey's Anatomy, Part 3. This is a LibriVox recording. All LibriVox recordings are in the public domain. For more information or to volunteer, please visit LibriVox.org. Anatomy of the Human Body, Part 3 by Henry Gray. The Diploic Veins The diploic veins occupy channels in the deploy of the cranial bones. They are large and exhibit at irregular intervals pouch-like dilatations. Their walls are thin and formed of endothelium resting upon a layer of elastic tissue. So long as the cranial bones are separable from one another, these veins are confined to the particular bones. But when the sutures are obliterated, they unite with each other and increase in size. They communicate with the meningeal veins and the sinuses of the durameter and with the veins of the pericranium. They consist of 1. The frontal, which opens into the supra-orbital vein and the superior sagittal finus. 2. The anterior temporal, which is confined chiefly to the frontal bone and opens into the spheno-perietal finus and into one of the deep temporal veins, through an aperture in the great wing of the sphenoid. 3. The posterior temporal, which is situated in the perietal bone and ends in the transverse sinus, through an aperture at the mastoid angle of the perietal bone or through the mastoid foramen. And 4. The occipital, the largest of the four which is confined to the occipital bone and opens either externally into the occipital vein or internally into the transverse sinus or into the confluence of the sinuses, circular hero phylae. The veins of the brain. The veins of the brain possess no valves and their walls owing to the absence of muscular tissue are extremely thin. They pierce the arachnoid membrane and the inner or meningeal layer of the durameter and open into the cranial venous sinuses. They may be divided into two sets cerebral and cerebellar. Cerebral veins, venous cerebri, are divisible into external and internal groups according as they drain the outer surfaces or the inner parts of the hemispheres. The external veins are the superior, inferior and middle cerebral. The superior cerebral veins, venous cerebri superioris, 8 to 12 in number, drain the superior lateral and medial surfaces of the hemispheres and are mainly lodged in the sulci between the gyri but some run across the gyri. They open into the superior sagittal sinus. The anterior veins runs nearly at right angles to the sinus. The posterior and larger veins are directed obliquely forward and open into the sinus in a direction more or less opposed to the current of the blood contained within it. The middle cerebral vein, venous cerebri media, superficial sylvan vein, begins on the lateral surface of the hemisphere and running along the lateral cerebral fissure ends in the cavernous or the sphenoperiatal sinus. It is connected, A. with the superior sagittal sinus by the great anastomotic vein of trollard which opens into one of the superior cerebral veins, B. with the transverse sinus by the posterior anastomotic vein of labe which courses over the temporal lobe. The inferior cerebral veins, venous cerebri inferioris of small size drain the under surfaces of the hemispheres. Those on the orbital surface of the frontal lobe join the superior cerebral veins and through these open into the superior sagittal sinus. Those of the temporal lobe anastomose with the middle cerebral and basal veins and join the cavernous sphenoperiatal and superior petrosal sinuses. The basal vein is formed at the anterior perforated substance by the union of A. a small anterior cerebral vein which accompanies the anterior cerebral artery, B. the deep middle cerebral vein, deep sylvian vein which receives tributaries from the insula and neighbouring gyri and runs in the lower part of the lateral cerebral fissure and C. the inferior striate veins which lead the corpus triatum through the anterior perforated substance. The basal vein passes backward around the cerebral peduncle and ends in the internal cerebral vein, vein of Galen. It receives tributaries from the intra peduncular fossa, the inferior horn of the lateral ventricle, the hippocampal gyrus and the midbrain. The internal cerebral veins, venous cerebri interne, veins of Galen, deep cerebral veins drain the deep parts of the hemisphere and are two in number. Each is formed near the intraventricular foramen by the union of the terminal and coroid veins. They run backward parallel with one another between the layers of the tila coroidia of the third ventricle and beneath the spleenium of the corpus callosum where they unite to form a short trunk, the great cerebral vein. Just before their union, each receives the corresponding basal vein. The terminal vein, vena terminalis, vena corporis triati, commensis in the groove between the corporis triatin and thalamus receives numerous veins from both of these parts and unites behind the crust furnaces of the coroid vein to form one of the internal cerebral veins. The coroid vein runs along the whole length of the coroid plexus and receives veins from the hippocampus, the fornix and the corpus callosum. The great cerebral vein, vena cerebrimagna, galenii, great vein of Galen, formed by the union of the two internal cerebral veins is a short median trunk which curves backward and upward through the spleenium of the corpus callosum and ends in the anterior extremity of the straight sinus. The cerebellar veins are placed on the surface of the cerebellum and are disposed in two sets, superior and inferior. The superior cerebellar veins, vena cerebelli superioris pass partly forward and medial world across the superior vermus to end in the straight sinus and the internal cerebral veins partly lateral world to the transverse and superior petrosal sinuses. The inferior cerebellar veins, vena cerebelli inferioris of large size end in the transverse superior petrosal and occipital sinuses. End of section 37. Section number 38 of Grey's Anatomy. Part 3. This is a LibriVox recording. All LibriVox recordings are in the public domain. For more information or to volunteer, please visit LibriVox.org. Recording by Morgan Scorpion. Anatomy of the Human Body. Part 3 by Henry Grey. Sinuses of the duomata ophthalmic veins, emissary veins. 3b5, the sinuses of the duomata, sinus duomatris, ophthalmic veins and emissary veins. The sinuses of the duomata are venous channels which drain the blood from the brain. They are devoid of valves and are situated between the two layers of the duomata and lined by endothelium continuous with that which lines the veins. They may be divided into two groups. One, a postural superior at the upper and back part of the skull and two, an antro inferior at the base of the skull. The postural superior group comprises the superior sagittal, inferior sagittal, straight, two transverse occipital. The superior sagittal sinus, sinus sagittalus superior, superior longitudinal sinus occupies the attached or convex margin of the falx cerebri. Commencing at the forearm and keekum through which it receives a vein from the nasal cavity, it runs from before backwards, grooving the inner surface of the frontal, the adjacent margins of the two parietals and the superior division of the cruciate eminence of the occipital. Near the internal occipital protuberance it deviates to one or other side, usually the right, and is continued as the corresponding transverse sinus. It is triangular in section, narrow in front, and gradually increases in size as it passes backward. Its inner surface presents the openings of the superior cerebral veins, which run for the most part obliquely forward and open chiefly at the back part of the sinus, though orifice is being concealed by fibrous folds. Numerous fibrous bands, cordae rullici, extend transversely along the inferior angle of the sinus, and lastly, small openings communicate with irregularly shaped venous spaces, venous lacunae, in the duomata near the sinus. There are usually three lacunae on either side of the sinus, a small frontal, a large parietal, and an occipital, intermediate in size between the other two. Most of the cerebral veins from the outer surface of the hemisphere open into these lacunae, and numerous arachnoid granulations, Pachionian bodies, project into them from below. The superior sagittal sinus receives the superior cerebral veins, veins from the deploy and duomata, and near the posterior extremity of the sagittal suture, veins from the pericranium, which pass through the parietal foramina. The numerous communications exist between this sinus and the veins of the nose, scalp and deploy. The inferior sagittal sinus, sinus sagittalis inferior, inferior longitudinal serenus, is contained in the posterior half or two-thirds in the free margin of the fog cerebri. It is of a cylindrical form, increases in size as it passes backward and ends in the straight sinus. It receives several veins from the fog cerebri, and occasionally a few from the medial surfaces of the hemispheres. The straight sinus, sinus rectus, tentorial sinus, is situated at the line of junction of the fog cerebri with the tentorium cerebelli. It is triangular in section, increases in size as it proceeds backward, and runs downward and backward from the end of the inferior sagittal sinus to the transverse sinus of the opposite side to that into which the superior sagittal sinus is prolonged. Its terminal part communicates by a cross branch with the confluence of the sinuses. Besides the inferior sagittal sinus, it receives the great cerebral vein, great vein of Galen, and the superior cerebellar veins. A few transverse bands cross its interior. The transverse sinuses, sinus transversus, lateral sinuses, are of large size and begin at the internal occipital protuberance, one generally on the right being the direct continuation of the superior sagittal sinus, the other of the straight sinus. Each transverse sinus passes lateral wood and forward, describing a slight curve with its convexity upward to the base of the petrous portion of the temporal bone, and lies, in this part of its course, in the attached margin of the tentorium cerebelli. It then leaves the tentorium and curves downward and medial wood to reach the jugular peramen, where it ends in the internal jugular vein. In its course, it rests upon the scramer of the occipital, the mastoid angle of the parietal, the mastoid part of the temporal, and, just before its termination, the jugular process of the occipital. The portion which occupies the groove on the mastoid part of the temple is sometimes termed the sigmoid sinus. The transverse sinuses are frequently of unequal size, that formed by the superior sagittal sinus being the larger, they increase in size as they proceed from behind forward. On transverse section the horizontal portion exhibits a prismatic, the curved portion a semi-cylindrical form. They receive the blood from the superior petrosal sinuses at the base of the petros portion of the temporal bone. They communicate with the veins of the perichranium by means of the mastoid and congeloid emissory veins, and they receive some of the inferior cerebral and inferior cerebellar veins, and some of the veins from the diploid. The petrosquamous sinus, when present, runs backward along the junction of the squamer and petrosportion of the temple and opens into the transverse sinus. The occipital sinus, sinus occipitalis, is the smallest of the cranial sinuses. It is situated in the attached margin of the folx cerebelli, and is generally single, but occasionally there are two. It commences around the margin of the foramen magnum by several small venous channels, one of which joins the terminal part of the transverse sinus. It communicates with the posterior internal vertebral venous plexuses, and ends in the confluence of the sinuses. The confluence of the sinuses, confluence sinurum, torcular herofilly, is the term applied to the dilated extremity of the superior sagittal sinus. It is of irregular form, and is lodged on one side, generally the right, of the internal occipital protuberance. From it the transverse sinus of the same side is derived. It receives also the blood from the occipital sinus, and is connected across the middle line with the commencement of the transverse sinus of the opposite side. The antero inferior group of sinuses comprises the two cavernous, two intercavernous, two superior petrosal, two inferior petrosal, and the basilar plexus. The cavernous sinuses, sinus cavernosis, are so named because they present a reticulated structure, due to their being traversed by numerous interlacing filaments. They are of irregular form, larger behind than in front, and are placed one on either side of the body of the sphenoid bone, extending from the superior orbital fissure to the apex of the petros portion of the temporal bone. Each opens behind into the petrosal sinuses. On the medial wall of each sinus is the internal carotid artery, accompanied by filaments of the carotid plexus. Near the artery is the abdicent nerve. On the lateral wall are the ocular motor and trochlear nerves, and the ophthalmic and maxillary divisions of the trigeminal nerve. These structures are separated from the blood flowing along the sinus by the lining membrane of the sinus. The cavernous sinus receives the superior ophthalmic vein through the superior orbital fissure, some of the cerebral veins, and also the small sphenoparietal sinus, which courses along the under surface of the small wing of the sphenoid. It communicates with the transverse sinus by means of the superior petrosal sinus, with the internal jugular vein through the inferior petrosal sinus and oplexus of veins on the internal carotid artery, with the pterigoid venous plexus through the foramen vesallii, foramen ovale, and foramen lacorum, and with the angular vein through the ophthalmic vein. The two sinuses also communicate with each other by means of the anterior and posterior intercavernous sinuses. The ophthalmic veins, 2 in number, superior and inferior, are devoid of valves. The superior ophthalmic vein, venous ophthalmica superior, begins at the inner angle of the orbit in a vein named the nasophrontal, which communicates anteriorly with the angular vein. It pursues the same course as the ophthalmic artery, and receives tributaries corresponding to the branches of that vessel. Forming a short trunk, it passes between the two heads of the rectus lateralis, and through the medial part of the superior orbital fissure, and ends in the cavernous sinus. The inferior ophthalmic vein, venous ophthalmica inferior, begins in a venous network at the full part of the floor and medial wall of the orbit. It receives some veins from the rectus inferior, oblicuous inferior, lacrimal sac and eyelids, runs backward in the lower part of the orbit, and divides into two branches. One of these passes through the inferior orbital fissure, and joins the pterigoid venous plexus, while the other enters the cranium through the superior orbital fissure, and ends in the cavernous sinus, either by a separate opening, or more frequently in common with the superior ophthalmic vein. The intercavernous sinuses, sini intercavernosi, are two in number, an anterior and a posterior, and connect the two cavernous sinuses across the middle line. The anterior passes in front of the hyperfysis cerebri, the posterior behind it, and they form with the cavernous sinuses of venous circle, circular sinus, around the hyperfysis. The anterior one is usually the larger of the two, and one or other is occasionally absent. The superior petrosal sinus, sinus petrosus superior, small and narrow, connects the cavernous with the transverse sinus. It runs lateral wood and backward from the posterior end of the cavernous sinus, over the trigeminal nerve, and lies in the attached margin of the tentorium cerebelli, and in the superior petrosal sulcus of the temporal bone. It joins the transverse sinus where the latter curves downward on the inner surface of the mastoid part of the temporal. It receives some cerebellar and inferior cerebral veins, and veins from the tympanic cavity. The inferior petrosal sinus, sinus petrosus inferior, is situated in the inferior petrosal sulcus formed by the junction of the petros part of the temporal with the basilar part of the occipital. It begins in the posterior inferior part of the cavernous sinus, and passing through the anterior part of the jugular paramen ends in the superior bulb of the internal jugular vein. The inferior petrosal sinus receives the internal auditory veins, and also veins from the medulla omblongata, pons, and undersurface of the cerebellum. The exact relation of the parts to one another in the jugular paramen is as follows. The inferior petrosal sinus lies medially and anteriorly with the meningeal branch of the ascending pharyngeal artery, and is directed obliquely downward and backward. The transverse sinus is situated at the lateral and back part of the paramen with the meningeal branch of the occipital artery, and between the two sinuses are the glossopharyngeal, vagus, and accessory nerves. These three sets of structures are divided from each other by two processes of fibrous tissue. The junction of the inferior petrosal sinus with the internal jugular vein takes place on the lateral aspect of the nerves. The basilar plexus. Plexus basilaris, transverse, or basilar sinus, consists of several interlacing venous channels between the layers of the duomata over the basilar part of the occipital bone, and serves to connect the two inferior petrosal sinuses. It communicates with the anterior vertebral venous plexus. Emissary veins. Emissaria. The emissary veins pass through the apertures in the cranial wall and establish communication between the sinuses inside the skull and the veins external to it. Some are always present, others only occasionally so. The principal emissary veins are the following. 1. A mastoid emissary vein, usually present, runs through the mastoid paramen and unites the transverse sinus with the posterior auricular or with the occipital vein. 2. A parietal emissary vein passes through the parietal paramen and connects the superior sagittal sinus with the veins of the scalp. 3. A network of minute veins, reticinalis hypoglossi, transverses the hypoglossal canal and joins the transverse sinus with the vertebral vein and deep veins of the neck. 4. An inconstant congeloid emissary vein passes through the congeloid canal and connects the transverse sinus with the deep veins of the neck. 5. A network of veins, retiforaminus ovalis, unites the cavernous sinus with the pterigoid plexus through the foramen ovale. 6. Two or three small veins run through the foramen lacerum and connect the cavernous sinus with the pterigoid plexus. 7. The emissary vein of the foramen ovisilius connects the same parts. 8. An internal carotid plexus of veins transverses the carotid canal and unites the carvenous sinus with the internal jugular vein. 9. A vein is transmitted through the foramen scicum and connects the superior sagittal sinus with the veins of the nasal cavity. End of section number 38. Section 39 of Gray's Anatomy Part 3 This is a LibriVox recording. All LibriVox recordings are in the public domain. For more information or to volunteer, please visit LibriVox.org. Recording by Eric Hale, Anatomy of the Human Body, Part 3, by Henry Gray. The veins of the upper extremity and thorax. The veins of the upper extremity are divided into two sets, superficial and deep. The two sets anastomose frequently with each other. The superficial veins are placed immediately beneath the integument between the two layers of superficial fascia. The deep veins accompany the arteries and constitute the venae cometantis of those vessels. Both sets are provided with valves, which are more numerous in the deep than in the superficial veins. The superficial veins of the upper extremity. The superficial veins of the upper extremity are the digital, metacarpal, cephalic, bacillic, median. Digital veins. The dorsal digital veins pass along the sides of the fingers and are joined to one another by oblique communicating branches. Those from the adjacent sides of the fingers unite to form three dorsal metacarpal veins, which end in a dorsal venous network opposite the middle of the metacarpus. The radial part of the network is joined by the dorsal digital vein from the radial side of the index finger and by the dorsal digital veins of the thumb and is prolonged upward as the cephalic vein. The ulnar part of the network receives the dorsal digital vein of the ulnar side of the little finger and is continued upward as the bacillic vein. A communicating branch frequently connects the dorsal venous network with the cephalic vein about the middle of the forearm. The volar digital veins on each finger are connected to the dorsal digital veins by oblique intercapitular veins. They drain into a venous plexus which is situated over the thenar and hypothenar eminences and across the front of the wrist. The cephalic vein begins in the radial part of the dorsal venous network and winds upward around the radial border of the forearm, receiving tributaries from both surfaces. Below the front of the elbow it gives off the vena mediana cubitai which receives a communicating branch from the deep veins of the forearm and passes across to join the bacillic vein. The cephalic vein then ascends in front of the elbow in the groove between the brachioradialis and the biceps brachii. It crosses superficial to the musculocutaneous nerve and descends in the groove along the lateral border of the biceps brachii. In the upper third of the arm it passes between the pectoralis major and deltoidius where it is accompanied by the deltoid branch of the thoracocromial artery. It pierces the coricoclavicular fascia and crossing the auxiliary artery ends in the axillary vein just below the clavicle. Sometimes it communicates with the external jugular vein by a branch which ascends in front of the clavicle. The accessory cephalic vein arises either from a small tributary plexus on the back of the forearm or from the ulnar side of the dorsal venous network. It joins the cephalic below the elbow. In some cases the accessory cephalic springs from the cephalic above the wrist and joins it again higher up. A large oblique branch frequently connects the bacillic and cephalic veins on the back of the forearm. The bacillic vein begins in the ulnar part of the dorsal venous network. It runs up the posterior surface of the ulnar side of the forearm and inclines forward to the anterior surface below the elbow where it is joined by the venous mediana cubitai. It ascends obliquely in the groove between the biceps brachii and pronator teres and crosses the brachial artery from which it is separated by the laceratus fibrosis. Filaments of the medial anti-brachial cutaneous nerve pass both in front of and behind this portion of the vein. It then runs upward along the medial border of the biceps brachii, perforates the deep fascia a little below the middle of the arm, and ascending on the medial side of the brachial artery to the lower border of the teres major is continued onward as the axillary vein. The median anti-brachial vein drains the venous plexus on the volar surface of the hand. It ascends on the ulnar side of the front of the forearm and ends in the bacillic vein or in the venomediana cubitai. In a small proportion of cases it divides into two branches, one of which joins the bacillic, the other the cephalic below the elbow. The deep veins of the upper extremity. The deep veins follow the course of the arteries forming their venaecomitantes. They are generally arranged in pairs and are situated one on either side of the corresponding artery and connected at intervals by short transverse branches. Deep veins of the hand. The superficial and deep volar arterial arches are each accompanied by a pair of venaecomitantes. The superficial and deep volar arterial arches are each accompanied by a pair of venaecomitantes which constitute respectively the superficial and deep volar venous arches and receive the veins corresponding to the branches of the arterial arches. Thus the common volar digital veins formed by the union of the proper volar digital veins open into the superficial and the volar metacarpal veins into the deep volar venous arches. The dorsal metacarpal veins receive perforating branches from the volar metacarpal veins and end in the radial veins and in the superficial veins on the dorsum of the wrist. The deep veins of the forearm are the venaecomitantes of the radial and ulnar veins and constitute respectively the upward continuations of the deep and superficial volar venous arches. They unite in front of the elbow to form the brachial veins. The radial veins are smaller than the ulnar and receive the dorsal metacarpal veins. The ulnar veins receive tributaries from the deep volar venous arches and communicate with the superficial veins at the wrist. Near the elbow they receive the volar and dorsal enterosius veins and send a large communicating branch, profunda vein, to the vena mediana cubitai. The brachial veins are placed one on either side of the brachial artery. Receiving tributaries corresponding with the branches given off from that vessel. Near the lower margin of the subscapularis they join the axillary vein. The medial one frequently joins the bacillic vein. The axillary vein begins at the lower border of the teres major. As the continuation of the bacillic vein increases in size as it ascends and ends at the outer border of the first rib as the subclavian vein. Near the lower border of the subscapularis it receives the brachial veins and close to its termination the cephalic vein. Its other tributaries correspond with the branches of the axillary artery. It lies on the medial side of the artery which it partly overlaps. Between the two vessels are the medial cord of the brachial plexus, the median, the ulnar, and the medial anterior thoracic nerves. It is provided with a pair of valves opposite the lower border of the subscapularis. Valves are also found at the ends of the cephalic and subscapular veins. The subclavian vein, the continuation of the axillary, extends from the outer border of the first rib to the sternal end of the clavicle where it unites with the internal jugular to form the inominate vein. It is in relation, in front, with the clavicle and subclavius, behind and above with the subclavian artery, from which it is separated medially by the scalenus anterior and the phrenic nerve. Below it rests in a depression on the first rib and upon the pleura. It is usually provided with a pair of valves which are situated about 2.5 centimeters from its termination. The subclavian vein occasionally rises in the neck to a level with the third part of the subclavian artery, and occasionally passes with this vessel behind the scalenus anterior. Tributaries This vein receives the external jugular vein, sometimes the anterior jugular vein, and occasionally a small branch which ascends in front of the clavicle from the cephalic. At its angle of junction with the internal jugular, the left subclavian vein receives the thoracic duct, and the right subclavian vein, the right lymphatic duct, the veins of the thorax. The inominate veins are two large trunks placed one on either side of the root of the neck, and formed by the union of the internal jugular and subclavian veins of the corresponding side. They are devoid of valves. The right inominate vein is a short vessel, about 2.5 centimeters in length, which begins behind the sternal end of the clavicle, and, passing almost vertically downward, joins with the left inominate vein just below the cartilage of the first rib, close to the right border of the sternum to form the superior vena cava. It lies in front and to the right of the inominate artery. On its right side are the phrenic nerve and the pleura, which are interposed between it and the apex of the lung. This vein, at its commencement, receives the right vertebral vein, and lower down the right internal mammary and right inferior thyroid veins, and sometimes the vein from the first intercostal space. The left inominate vein, about 6 centimeters in length, begins behind the sternal end of the clavicle, and runs obliquely downward and to the right behind the upper half of the manubrium sterni to the sternal end of the first right costal cartilage, where it unites with the right inominate vein to form the superior vena cava. It is separated from the manubrium sterni by the sternohioidius and sternothyrioidius, the thymus, or its remains, and some loose areolar tissue. Behind it are the three large arteries, inominate, left common carotid, and left subclavian, arising from the aortic arch together with the vagus and phrenic nerves. The left inominate vein may occupy a higher level, crossing the jugular notch and lying directly in front of the trachea. Tributaries. Its tributaries are the left vertebral, left internal mammary, left inferior thyroid, and the left highest intercostal veins, and occasionally some thymic and pericardiac veins. Peculiarities. Sometimes the inominate veins open separately into the right atrium. In such cases, the right vein takes the ordinary course of the superior vena cava. The left vein, left superior vena cava, as it is then termed, which may communicate by a small branch with the right one, passes in front of the root of the left lung, and, turning to the back of the heart, ends in the right atrium. This occasional condition in the adult is due to the persistence of the early fetal condition, and is the normal state of things in birds, and some mammalia. The internal mammary veins are vena cometantis to the lower half of the internal mammary artery, and receive tributaries corresponding to the branches of the artery. They then unite to form a single trunk, which runs up on the medial side of the artery, and ends in the corresponding inominate vein. The superior phrenic vein, i.e., the vein accompanying the periocardiacal phrenic artery, usually opens into the internal mammary vein. The inferior thyroid veins, two, frequently three or four, a number, arise in the venous plexus on the thyroid gland, communicating with the middle and superior thyroid veins. They form a plexus in front of the trachea behind the sternothyroidii. From this plexus, a left vein descends and joins the left inominate trunk, and a right vein passes obliquely downward and to the right across the inominate artery to open into the right inominate vein, just at its junction with the superior vena cava. Sometimes the right and left veins open by a common trunk in the latter situation. These veins receive esophageal, tracheal, and inferior laryngeal veins, and are provided with valves at their terminations in the inominate veins. The highest intercostal vein, right and left, drain the blood from the upper three or four intercostal spaces. The right vein passes downward and opens into the venous icos. The left vein runs across the arch of the aorta, and the origins of the left subclavian and left common carotid arteries, and opens into the left inominate vein. It usually receives the left bronchial vein, and sometimes the left superior phrenic vein, and communicates below with the accessory hemiasygos vein. The superior vena cava drains the blood from the upper half of the body. It measures about seven centimeters in length, and is formed by the junction of the two inominate veins. It begins immediately below the cartilage of the right first rib close to the sternum, and, descending vertically behind the first and second intercostal spaces, ends in the upper part of the right atrium opposite the upper border of the third right costal cartilage. The lower half of the vessel is within the pericardium. In its course, it describes a slight curve, the convexity of which is to the right side. Relations. In front are the anterior margins of the right lung and pleura with the pericardium intervening below. These separated from the first and second intercostal spaces, and from the second and third right costal cartilages. Behind it are the root of the right lung and the right vagus nerve. On its right side are the phrenic nerve and right pleura. On its left side, the commencement of the inominate artery and the ascending aorta, the latter overlapping it. Just before it pierces the pericardium, it receives the azygos vein and several small veins from the pericardium and other contents of the mediastinal cavity. The portion contained within the pericardium is covered, in front and laterally, by the cirrus layer of the membrane. The superior vena cava has no valves. The azygos vein begins opposite the first or second lumbar vertebrae by a branch, the ascending lumbar vein, sometimes by a branch from the right renal vein or from the inferior vena cava. It enters the thorax through the aortic hiatus in the diaphragm and passes along the right side of the vertebral column to the fourth thoracic vertebra, where it arches forward over the root of the right lung and ends in the superior vena cava just before that vessel pierces the pericardium. In the aortic hiatus, it lies with the thoracic duct on the right side of the aorta. In the thorax, it lies upon the intercostal arteries on the right side of the aorta and thoracic duct, and is partly covered by pleura, tributaries. It receives the right subcostal and intercostal veins, the upper three or four of these letter, opening by a common stem, the highest superior intercostal vein. It receives the hemiazygos veins, several esophageal, mediastinal and pericardial veins, and, near its termination, the right bronchial vein. A few imperfect valves are found in the azygos vein, but its tributaries are provided with complete valves. The intercostal veins on the left side, below the upper three intercostal spaces, usually form two trunks, named the hemiazygos and accessory hemiazygos veins. The hemiazygos vein begins in the left ascending lumbar or renal vein. It enters the thorax through the left crust of the diaphragm and ascending on the left side of the vertebral column as high as the ninth thoracic vertebra passes across the column behind the aorta, esophagus, and thoracic duct to end in the azygos vein. It receives the lower four or five intercostal veins and the subcostal vein of the left side and some esophageal and mediastinal veins. The accessory hemiazygos vein descends on the left side of the vertebral column and varies inversely in size with the highest left intercostal vein. It receives veins from the three or four intercostal spaces between the highest left intercostal vein and highest tributary of the hemiazygos. The left bronchial vein sometimes opens into it. It either crosses the body of the eighth thoracic vertebrae to join the azygos vein or ends in the hemiazygos. When this vein is small or altogether wanting, the left highest intercostal vein may extend as low as the fifth or sixth intercostal space. In obstruction of the superior vena cava, the azygos and hemiazygos veins are one of the principal means by which the venous circulation is carried on, connecting as they do the superior and inferior vena cava and communicating with the common iliac veins by the ascending lumbar veins and with many of the tributaries of the inferior vena cava. The bronchial veins return the blood from the large bronchi and from the structures at the roots of the lungs. That of the right side opens into the azygos vein near its termination. That of the left side into the highest left intercostal or the accessory hemiazygos vein. A considerable quantity of the blood which is carried to the lungs through the bronchial arteries is returned to the left side of the heart through the pulmonary veins. The veins of the vertebral column, the veins which drain the blood from the vertebral column, the neighboring muscles, and the meninges of the medulla spinalis form intricate plexuses extending along the entire length of the column. These plexuses may be divided into two groups, external and internal, according to their positions inside or outside the vertebral canal. The plexuses of the two groups enastomose freely with each other and end in the intervertebral veins. The external vertebral venous plexuses, best marked in the cervical region, consist of anterior and posterior plexuses which enastomose freely with each other. The anterior external plexuses lie in front of the bodies of the vertebrae, communicate with the base of vertebral and intervertebral veins, and receive tributaries from the vertebral bodies. The posterior external plexuses are placed partly on the posterior surfaces of the vertebral arches and their processes, and partly between the deep dorsal muscles. They are best developed in the cervical region, and they are enastomose with the vertebral, occipital, and deep cervical veins. The internal vertebral venous plexuses lie within the vertebral canal between the dura mater and the vertebrae, and receive tributaries from the bones and from the medulla spinalis. They form a closer network than the external plexuses, and, running mainly in a vertical direction, form four longitudinal veins, two in front and two behind. They therefore may be divided into anterior and posterior groups. The anterior internal plexuses consist of large veins which lie on the posterior surfaces of the vertebral bodies and intervertebral fibrocartilages on either side of the posterior longitudinal ligament. The anterior internal plexuses consist of large veins which lie on the posterior surfaces of the vertebral bodies and intervertebral fibrocartilages on either side of the posterior longitudinal ligament. Under cover of this ligament, they are connected by transverse branches and to which the base of vertebral veins open. The posterior internal plexuses are placed one on either side of the middle line in front of the vertebral arches and ligamenta flava, and anastomose by veins passing through those ligaments with the posterior external plexuses. The anterior and posterior plexuses communicate freely with one another by a series of venous rings, one opposite each vertebra. Around the foramen magnum, they form an intricate network which opens into the vertebral veins and is connected above with the occipital sinus, the bacillar plexus, the condyloid emissary vein, and the reet canalis hypoglossi. The base of vertebral veins emerge from the foramina on the posterior surfaces of the vertebral bodies. They are contained in large, tortuous channels in the substance of the bones. Similar in every respect to those found in the diplo of the cranial bones, they communicate through small openings on the front and sides of the bodies of the vertebrae with the anterior external vertebral plexuses and converge behind to the principal canal, which is sometimes doubled toward its posterior part, and open by valved orifices into the transverse branches which unite the anterior internal vertebral plexuses. They become greatly enlarged in advanced age. The intervertebral veins accompany the spinal nerves through the intervertebral foramina. They receive the veins from the medulla spinalis, drain the internal and external vertebral plexuses, and end in the vertebral intercostal lumbar and lateral sacral veins, their orifices being provided with valves. The veins of the medulla spinalis are situated in the pia matter and form a minute tortuous venous plexus. They emerge chiefly from the median fissures of the medulla spinalis and are largest in the lumbar region. In this plexus, there are two median longitudinal veins, one in front of the anterior fissure and the other behind the posterior sulcus of the cord, and four lateral longitudinal veins which run behind the nerve roots. They end in the intervertebral veins. Near the base of the skull, they unite and form two or three small trunks which communicate with the vertebral veins and then end in the inferior cerebellar veins or in the inferior patrosal sinuses. End of section 39. Recording by Eric Hale