Pupil abnormalities after orbital surgery
Reviewed by James Hsuan

This is a retrospective review of 287 patients who underwent removal of an orbital cavernous haemangioma (cavernous venous malformation), to ascertain the incidence of surgically induced pupillary abnormalities. Forty-four patients had lesions removed from the anterior or extraconal orbit, none of which developed pupillary problems. Of the remaining 243 with intraconal lesions, 60 (25%) were found to have postoperative mydriasis, vermiform movements, or a sectoral palsy. Apical lesions had the highest incidence (48%) followed by inferior to the optic nerve (44%) and posterior third of orbit (36%). Lesions in the inferior / inferotemporal quadrant had a significantly higher rate (39%) compared to superior / superotemporal (10%) and nasal / inferonasal (16%). The location of the ciliary ganglion in the lateral intraconal orbit is the most likely explanation for these findings. Longer term follow-up was available for 50 patients, and after a median 14 years, 43 had resolved or markedly improved, although 15 of these still had a tonic pupil with some accommodative difficulties in younger patients. Interestingly, over half of all affected patients were thought to have a normal pupil at the end of surgery, developing the abnormality in the immediate postoperative period. The authors suggest this may be a toxic neuropraxia secondary to the inflammatory response.

Pupillary abnormalities after excision of orbital cavernous venous malformations.
Vadhani K, Rose GE.
OPHTHALMIC PLASTIC AND RECONSTRUCTIVE SURGERY
2023;39(1):40-3.