The objective of this study was to assess the etiology of
lateral rectus palsies in patients undergoing lumbar myelograms with
Iopamidol (
Isovue; ER Squibb and Sons, Princeton, NJ, USA;
Niopam, E Merc, UK.). An audit of the departmental
orthoptic record revealed two patients who had suffered
abducens palsies after myelograms. A further search revealed three additional patients who had suffered similar complications. The incidence of
abducens palsy in patients undergoing myelography with the
contrast agent Iopamidol was found to be 1 in 500 in around 2,500 myelograms performed under standard conditions. It would appear that
lateral rectus palsy in myelography is the result of the lumbar puncture, the neurotoxic effect of the
contrast agent, or a combination of the two in patients with an already compromised neurophysiologic state. This is the first series to associate this problem with
Iopamidol. Although usually a serious
neurologic symptom, when associated with contrast myelography using
Iopamidol it is important to appreciate that such symptoms usually resolve of their own accord.