 కాస్ట్రీటేఎఠింveyard పత్డభ�超 argue నావై Auntie నిందార౒ి� karma l.camp lies belongs Ber equation Все a 5 9 5 7 11 9 pre-ganglionic lesions are the lesions proximal to the neural pheramen that is proximal to the dorsal nor root ganglion. These are the root abulsion injuries like long thoracic nerve palsy because of C5, C6 and C7 root involvement or phrenic nerve palsy because of C3, C4 and C5 root involvement or hornar syndrome because of T1 root abulsion. In contrast, post-ganglionic lesions are the lesions distilled to the neural pheramen or distilled to the dorsal root ganglion. These are the abulsions of the terminal nerves. But this distinction of pre-ganglionic lesions and post-ganglionic lesions is of critical importance because you all know the pre-ganglionic lesions are located in the central nervous system proximal to the dorsal root ganglion. And in the central nervous system the regeneration of the neurons are absent. So the prognosis of the pre-ganglionic plexopathy is very grave. But in contrast the post-ganglionic lesions are located beyond the dorsal nor root ganglion or in the peripheral nervous system. And in the peripheral nervous system the regeneration of the neurons are far better. So the prognosis of the post-ganglionic plexopathy are far better than the pre-ganglionic ones. So here comes the role of radiology because MRI is the best modality for diagnosing and localizing the site injury in case of brachial plexopathy because the localization whether it's a pre-ganglionic one or post-ganglionic one determines the prognosis and the management. And out of the all MRI sequences the star inversion recovery is the best sequence for diagnosis and localizing brachial plexopathy. As far as contrast is concerned intravenous gadolinium is administered in patients with brachial plexopathy due to tumors and mass. But gadolinium is not generally administered in patients of traumatic brachial plexopathy. Coming to the anatomy, as we all know brachial plexopathy is formed by the joining of the roots of C5, C6, C7, C8 and T1 roots. Then all these roots form the three trunks upper medial and lower trunks and from each trunks there occurs anterior and posterior division and all these divisions join to form three cords, medial cord, lateral cord and posterior cord. And all these cords finally give the terminal branches. But clinically as we see the clinically we divide the brachial plexopathy into supra-clobucular legions and intra-clobucular legions. So the supra-clobucular plexopathy involve the roots and the trunks and the intra-clobucular legions involve the cords and the terminal branches. As we see in the supra-clobucular legions there will be involvement of the roots like the involvement of the fending nerve roots, long thoracic nerve and dorsal scapula nerve also the involvement of the trunks like upper medial and lower trunks could be involved involvement of the nerves from the trunks like nerve to subclavius and supra scapula nerve. So all these comes under the supra-clobucular brachial plexopathy. But in case of intra-clobucular brachial plexopathy there will be involvement of the cord and the terminal branches. Like the branches from the lateral cord like lateral pectoral nerve, medial pectoral nerve and lateral root of medial nerve. So all these comes from the lateral cord also from the medial cord then all the nerve could be involved and from the posterior cord like axillary nerve, radial nerve injury, thoracodorsal nerve injury, upper supra-clobucular nerve injury these all comes under the intra-clobucular brachial plexopathy. But as far as radiology is concerned we have to only distinguish between whether it is a preganglionic injury or a postganglionic injury. Coming to the preganglionic injury as we see the preganglionic injury is near the spinal cord. So there will be edema of the spinal cord with some hemorrhage in the nerve root. They will show blooming on GRE and susceptibility to lateral imaging. And there will be characteristically there will be pseudo-meningosil formation. Sido-meningosil formation will which will appear t2 star hyper intensity near the nerve root. So pseudo-meningosil formation is a characteristic of preganglionic brachial plexopathy. Here the image is showing the pseudo-meningosil formation which is tube to bride. And as indirect sign we can see the enhancement of the para-spinal muscle also. Then coming to the postganglionic injury as we will see the postganglionic injury is the injury beyond the dorsal marrow ganglia. So as MRI finding the nerve roots will be normal at origin but they will be indistinctly distally. And all the terminal nerves there will appear t2 hyper intense and there will be thickening and some edema. As indirect evidence we can see clavicular fracture and sometimes there could be neoplastic etiology like pancoast tumor. So pancoast tumor generally causes postganglionic brachial plexopathy. Here is the t2 star coronal section showing the hyper intensity and edema in the terminal nerves. So this is a postganglionic type of injury. Coming to the case discussion. The case one there is a 35 year male who is presented with right clavicular mass with weakness in the right upper limb. Here in the star image it shows the hyper intense mass lesion in the right clavicular region with some kind of edema. So it is in the clavicular and infraclavicular part with t2 star hyper intensity and with edema. And so it is a suggestive postganglionic type of brachial plexopathy. Thickening edema of the nerves and t2 hyper intensity are the level of clavicular. Then coming to also in the axial section in the right side also shows hyper intensity to hyper intense mass arising from the clavicular. So this is a type of postganglionic type brachial plexopathy which is a favourable prognosis. Prognostically is favourable. Then coming to case two. Case two is a one year female. One year old female with left upper limb abnormal movement. There is history of stress in use also there. When we see the MRI look at the MRI in the in the star coronal image. Along the nerve roots there is cystic t2 star hyper intensity with pseudo meningosil formation. So once we see the pseudo meningosil formation is a characteristic of preganglionic injury. So here is the hyper intensity along the left spinal cord nerve roots. So these are the with pseudo meningosil formation these are characteristics of preganglionic injury. And as we all know the preganglionic injuries are of grave prognosis. Also in the axial section in the axial t2 fat suffer section also. There is hyper intensity t2 star hyper intensity along the left side of the spinal cord in the spinal root region with pseudo meningosil formation. So pseudo meningosil formation with t2 hyper intensity in the spinal nerve root region is a characteristic of preganglionic type of brachial plexopathy. It is a very poor prognosis and so prognostically because it involves it is in the central nervous system which has no regeneration potential. So it is a very poor prognosis. So the MRI is most importantly as conclusion we can say the MRI apart from the diagnosis it is able to localize whether it is a preganglionic injury or postganglionic injury. It will determine the prognosis and management point of view. These all are my references.