 Let us understand the concept of exiting and traversing nerves. The first nerve that comes out of the spinal cord is the semen nerve which comes out above the lateral process of semen vertebra. So the nerve which comes out from the semen to neural phramen is the C2 nerve. Similarly, the nerve which comes out from the C3 for neural phramen would be the C4 nerve. So if you remember that in cervical spine the exiting nerve which comes out from the phramen is the larger numbered nerve. So the nerve which is coming out from C67 neural phramen will be the C7 nerve. From C7 D1 neural phramen we have an addition nerve which is coming out which is the C8 nerve. So this is the C7 D1 neural phramen. The nerve which is coming out is the C8 nerve. And from D1 to neural phramen onwards the D1 nerve will come out. So in the dorsal and lumbar spine the nerve which is coming out from the neural phramen has got a smaller number. The nerve which is coming out from D1 to neural phramen will be D1. One which is coming out from the D67 phramen will be D6. Similarly, the nerve which is coming out from L45 neural phramen will be L4. So the concept of traversing nerve comes in the dorsal and lumbar spine. The nerve when exits from the spinal cord traverses down to the next level and then comes out from the neural phramen at a lower level. So this is the traversing part of the nerve. This concept comes in the dorsal spine and lumbar spine. So we have got traversing nerve and the exiting nerve in dorsal and lumbar spine. This is not the case in the cervical spine. So when we look at these exclusions, the extrusion which is paracentral cause compression of the traversing nerve in the lateral visus and when it is far lateral it is called compression of the exiting nerve in the neural phramen. So that is difference here. Coming to the anatomical plexus. So this is the color illustration showing the different compressive brachial plexus on the right side. The part here in golden color or yellow color is the roots. So these are the roots of brachial plexus. This is the C5, C6, C7, C8 and D1 roots. We know that the roots are formed by the ventricular dorsal rootlets along the dorsal rootlet there is a dorsal ganglion. So this is the pre-ganglion segment of the root and this is the post-ganglionic segment. The roots in turn join to form the trunks of brachial plexus. The C5 and C6 roots join to form the upper trunk. C7 root continues as the middle trunk and the C8 D1 roots join to form the lower trunk. So the trunks traverse between the anterior posterior scallion muscles. So after the roots we have got trunks. Trunks will be passing between the scallion muscles which are shown here. From the lateral margin of the scallion muscles to the upper margin of the clavicle we have got the divisions. So roots, trunks, divisions, each trunk will divide into anterior and posterior divisions. The divisions will join to form the cords. So the cord travels from the level of clavicle up to the outer margin of the lateral muscles. So these in pink color are the cords. And then the cords will give rise to the middle branches as the side branches which are shown in the magenta color over here. So these are the roots, these are the trunks in blue, these are the divisions intercoils for light blue color. These are the cords in pink color and these are the branches in magenta. This is a detailed anatomy now. The C5 and C6 roots join to form the upper trunk. So these are the scallion muscles. So between the scallion muscles we have got the trunks. C5 and C6 roots join to form the upper trunk. C7 root continues as the middle trunk. C8 and D1 roots join to form the lower trunk. The trunks divide into anterior and posterior divisions. These divisions join to form the cords. Now the posterior divisions of all the three trunks, upper, middle, and lower join to form the posterior cord. The anterior division of the lower trunk continues as the middle cord. And the anterior divisions of the upper and middle trunks join to form the lateral cord. So the cords extend from the level of clavicle up to the outer margin of the petrol muscles. These are named the medial lateral posterior depending on their relation to the subterran artery. So this is subterran artery here. The cord which is medial to it is a medial cord. One which is lateral is a lateral cord. And the cord behind the posterior is a posterior cord. These cords will then give rise to side branches and terminal branches. The other terminal branches show here the medial cord will give rise to a branch which joins with another branch from the lateral cord from the median nerve. The inner nerve comes solely from the medial cord. And the posterior cord divides into two terminal branches, the axillary and the radium nerves. We will not go into this part as of now. Second major is the oblique coronary T1 image which shows the components of brachial plexus. These are the roots of brachial plexus. These are the level of scallion muscles. So we have seen the trunks over here. These are the divisions from the automotive of scallion muscles at the level of clavicle. These are the divisions. The divisions then join to form the cords. This is the asterisk here, shows the subterran artery. So the cord medial cord will be the medial cord. This is lateral cord and posterior cord. So we have got sagittal images, sagittal T1 images here to show the relation of the cord to the subterran artery. So this is the oblique sagittal image here. This is the subterran artery, subterran vein. The cord which is medial to it is the medial cord. The lateral cord is lateral to it and this is the posterior cord. So this is the image obtained somewhat laterally at the level of axilla. So this is the subterran artery. So this is the plenatory. This is the cord which is medial to medial cord. This is the posterior cord and this is the lateral cord. Coming to the indications of brachial plexus imaging. The most common indication as we know are chroma. Then we have put in our comparison of the entrapment syndromes imaging of the inflammatory brachial plexopathy and neoplasms. Most importantly, chroma. From a surgical and prognostic point of view, the injuries to brachial plexus are classified into three categories. Preganglionic, postganglionic and a combination of four. So preganglionic injuries largely comprise of nerve abulsions. These require major procedure like neurotization. Postganglionic lesions are further classified into two lesions in continuity, which will require rehabilitation and neurolysis and lesions with nerve discontinuity, like nerve transaction or severe neurotomysis. These require nerve repair or drafting. The overall spectrum of injuries ranges from neuroplexia or chasing guilt, which is most common, to axonomesis, to partial neurotomesis, with neuroma in temporary formation, to complete nerve lesion of transactions, severe neurotomesis or nerve divergence. These categories here, severe neurotomesis, nerve transaction and nerve divergence will require urgent surgery. Coming to interesting case here, this is a patient who has both injury in vehicle, he has suffered a vehicle accident and he has been injured to the right arm and shoulder. He comes several weeks after the injury with complaints of right upper limb weakness and bristing. So when there is new imaging of patients with brachal plexus, suspected brachal plexus of injury, the first sequence that we take should always be a societal sequence with cervical spine. There is no point in imaging the brachal plexus for half an hour and saying that it is completely normal and then realizing that the patient has got cervical cord injury, something like a cord entusion or intramural hemorrhage which would exclude the complaints. So first and foremost, the first sequence should be a societal T2 sequence through the cervical cord. So this is societal T2 imaging from cervical spine. The cord looks perfectly fine, there is no evidence of confusion or edema or hemorrhages. But when we come slightly far laterally on the right side and see here that there are well-defined cystic lesions in the neural fermion at C67, C71 and D1 to events. So these are the existing nerves which are looking intact. But in this neural fermion, there are cystic areas which could very well be traumatic pseudomeningosemes. So when we take actual section as we just showed earlier, this is the actual 3D space sequence. We can see that the ventral and dorsal rootlets are not seen at this level, C7 and 11. They are seen on the left side. And so there is complete nervous avulsion of the right-sided C1 root here. And there is a formation of a traumatic pseudomeningosem. This is nervous avulsion. So these are 3D sequences, 3D star sequences with deformations. Clearly show the traumatic pseudomeningosemes from here at C67, C71 and D1 to events. So these are involving the roots here. And these meningosemes are then coalescing here to form a large pseudomeningosem sac. And the nerves here are retracted and it matters. So we can actually calculate the distance of retraction of the nerves from the insertion in the core. So the surgeon can have a fair amount of idea about the surgical procedure to be taken. So this is a classical case of right-sided C1 injury with traumatic nerve avulsion and a pseudomeningosem formation. These are 3D voluminated images of the same patient. We can very nicely see the pseudomeningosemes coalescing to form a big sac here. And these are the retracted, pedometer's nerves on the reticulate axis. Another patient, a young adult, again, a vehicle accident and a fracture in mid-part of a clavicle. He had a suspension of reticulate acid injury. But he didn't immediately come up with an accident. He waited for some time. Treating surgeon gave him a few weeks' time. When the patient did not recover after a few weeks, he still had a pulmonary weakness. The patient was sent for an imaging. So these are the images obtained immediately after trauma, which clearly show there is a immediate fracture here involving the mid-part of the right clavicle. These are the voluminated images. There's again a fracture here with some displaced bone pigment here. And when we did MRI scan of the brachial plexus, a few weeks later, this is what we see. Again, the first sequence that we take is a suggested T2 sequence to the cervical cord. The cervical cord here is completely fine. So we move on to the brachial plexus part. These are coronal stir images. Now this, and this level, if you see, this is the area of fracture. So these are the patterns of the bone. This is the callus formation around the fracture side. And these are the nerves of the brachial plexus. Now if you see all the components of brachial plexus, right from the trumps, divisions, cords are all edematous. And I would call this something like neuroplaxia on stretching, but then I would be wrong. If I look carefully at this level, one of the nerves here is showing breach incontinuity. When I do a volume rendering, this is what I see. So I need to evaluate this area better. And when I zoom it, this is what I see. Yes, definitely there's a transaction of nerve. This is the middle trunk of the brachial plexus, which is showing complete loss in continuity. So this is nerve transaction, severe injury involving the middle trunk of the brachial plexus, which would need a surgical repair. So from neuroplaxia, we are moving to nerve transaction. So we can see that this patient has got transaction of the middle trunk of brachial plexus. The rest of the nerves in brachial plexus are showing changes of edema or neuroplaxia. So this is definitely candidate for surgery. Sometimes CT myelography is required. A patient who has got in areas where MR is not available, or patients who have got patients who cannot be urgently taken for MRI. In such cases, CT myelography can be tried. This is a patient, again, with similar findings here. The ventral and dorsal root traits are seen on the left side, on the right side they are not seen. And we are seeing that there's contrast pooling here in a sodium myeloscis sac here. This is the nerve diversion on CT myelography. So this is the reporting format we sometimes follow. It is good to mention the report in two different parts, pre-ganglionic injury and post-ganglionic injury. So this is a patient with nerve diversion at different levels. As we said, we have to mention whether the nerve diversion was pre-ganglionic part. And in the post-ganglionic part, obviously, there will be changes of neuroplaxia and of transaction or exonormous or neurotomysis. Coming to bony impediments. Now this is an interesting case for a young student. He is a medical graduate. And he has got an intermittent brachial plexus involving the left upper limb. The x-ray here clearly shows the cervical ribs. The smaller cervical rib on the right side and larger on the left side. The left side cervical rib here is seen to articulate the mid part of the left front rib. So how does this affect the brachial plexus? Let us see. We have a set of coronal images here, oblique coronal images showing brachial plexus. These are the nerves of brachial plexus. So this would be level of the roots, the trunks and divisions of brachial plexus and this would be level of the cord, because this is the clavicle. We will just go to the next image here. Again, the nerves of brachial plexus, nicely seen. Now this is the left-sided cervical rib. And in this image, you can clearly see that the rib is articulating with the left first rib. And this articulation is very closely operating and impinging on the roots of brachial plexus. So this is the site of the articulation. And these are the level of trunks and cords of brachial plexus. The divisions and cords of brachial plexus. These are getting in pain. So when the patient has got something, abduction extrusion of the left upper limb, the nerves of brachial plexus are impinged by the cervical rib. So this patient was subjected to surgery. The cervical rib was removed and he did have improvement in the complex. Another patient presented with upper extremity pain, but he also had on further proving, he gained his clear of weight loss and a lot of peptides since few months. The media clearly shows the well-defined mass of the optical part of the left hemiphox. If you seem to be inflicting that surrounding fat pains, the fat pains of the right side are intact. And on the next media, it clearly shows that there is an invasion of the even root of the brachial plexus and maybe the lower trunk. So this is the classical case of pancostume of left limb, which is embedded in the brachial plexus. Another patient, adult female patient, is treated for sea breast. She has got nodule legions along the nerves of brachial plexus, which are classical of metastasis involving the brachial plexus. Another young adult female patient with right upper limb complaints, the image itself is very characteristic. We have got a dumbbell check region, which is coming out from the neural ferment with well-defined margins. This is where most likely a non-ship tumor involving the brachial plexus. A 38-year-old male patient who had his vehicle accident a few months back, now he has up to a few months, he has come with contents of right brachial plexopathy. This image clearly shows a well-defined region of brachial plexus with two differential intensities, the central part here. This impact is a supra-analysm involving the suplean artery, which is causing right-sided brachial plexopathy. Another elderly female patient who has received radiotherapy for sea breast seven months back presents with brachial plexopathy. Now, in this case, there are no nodules along the nerves, so we don't see any obvious metastasis, but there is increased intensity of the cause of brachial plexus here. And these might show increased enhancement. So, this is an all-likely root. Since the patient has got C.L.F. breast, she has received radiotherapy. So, this is post-brachial plexopathy of the brachial plexus. Now, she has got similar findings. As the earlier patient, there is extensive edema and hyperintensity involving the root, stumps and pores of brachial plexus. But she didn't have any previous history. She had a small episode of viral illness one or two weeks back. So, in all likelihood, this could be something like arsenish term as syndrome, inflammatory brachial plexopathy. So, we're finding, we've mentioned about some of the emerging MRI techniques that we can use for brachial prasimaging, DTI, or Diffusion Tense Imaging, which measures diffusion of water in 3D space or in milliseconds of time, and to give indication of tissue alteration, it has got high sensitivity for detecting changes in tissue anastropy. So, this is very similar to DTI that we take to ascertain the integrity of the longitudinal white matter cracks in brain. And this is still an immediate technique. This brings me to the end of the presentation. I hope you enjoyed this presentation and found it informative. Thank you.