No pupillary dilation lag after carotid endarterectomy

Abstract

Since headache after carotid endarterectomy is a common complication and has been associated with decreased oculosympathetic activity, we wondered if sympathetic denervation occurs in carotid endarterectomy as evidenced by dilation lag. Dilation lag is considered a sensitive pupillary indication of an oculosympathetic lesion. Sixteen consecutive patients with stenosis of the internal carotid artery were endarterectomized. Photographic pupillometry was used to demonstrate dilation lag. No significant dilation lag was seen as a consequence of the operation in any patient. However, 50% reported postendarterectomy headache. Consequently, the results from this series do not indicate that carotid endarterectomy is associated with oculosympathetic lesion, nor that damage to the sympathetic fibers explains the postendarterectomy headache. This conclusion was further supported by the findings in additional five patients in whom the pupillary responses to pholedrine eye drops were studied before and after carotid endarterectomy. No peroperatively induced postganglionic sympathetic lesion could be demonstrated by this method. Two of the pholedrine-tested patients had evidence of pre-existing postganglionary sympathetic lesion, which in one individual normalized after carotid endarterectomy.