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What is Expansion of the contrast filled space in myelography is seen in: and explain in detail?
Ans: A. Intramedullary tumor(Ref Sutton 6/e p254: Neurology in Clinical Practice 4/e Vol I p579)Myelography:Expansion of contrast filled space (i.e. subarachnoid space) - Any intramedullaty extradural lesion (meningioma).Sometimes filling defect causing "meniscus sign" demonstrable.Levels of Block in MyelographySiteTypical AppearanceExtradural blockFeathered appearanceIntradural Extramedullary blockMeniscus signWidening of ipsilateral subarachnoid spaceIntramedullary blockWidening of the cordTrouser leg appearance