Radiology, Vol 151, 417-419, Copyright © 1984 by Radiological Society of North America
Epidural block: myelographic evaluation with a single-puncture technique using metrizamide
WM Kelly, P Badami and W Dillon
A simplified technique using metrizamide for myelographic delineation of
extrinsic spinal cord blocks is described. This method was successfully
used in eight consecutive examinations without adverse effects. A single
lumbar puncture is followed by instillation of metrizamide into the
subarachnoid space. With the needle left in place and the patient in the
Trendelenburg position, the contrast agent is sequentially displaced above
any encountered extradural blocks by further injection of diluent or
sterile saline into the caudal thecal sac. Thus, multiple levels of
blockage may be defined at their upper and lower margins. This method
offers an expedient and safe alternative to combined lumbar and C1-2
lateral cervical puncture, leaves a minimum amount of metrizamide "trapped"
below a block, and has several advantages over use of iophendylate.
Additionally, the examination may be supplemented with CT scanning when
desirable.
