Pupillary Abnormalities After Excision of Orbital Cavernous Venous Malformations.

AIMS: The aim of this study was to determine the incidence and recovery rate for pupillary abnormalities after excision of orbital cavernous venous malformations (OCVMs).

METHODS: Retrospective case-note and imaging review for patients with OCVMs, with an estimation of odds ratios (ORs) in relation to the position of the mass and surgical approach.

RESULTS: The 287 included patients (176 female; 61%) presented at a mean age of 46.5 years: 243/287 (85%) OCVMs were intraconal, 253/287 (88%) located in the posterior two-thirds of the orbit, and 29/287 (11%) wedged tightly in the apex. Pupillary changes-varying from minor sectoral paresis (only evident on slit-lamp examination) to a marked mydriasis-were noted in 21% (60/287) of patients and were strongly associated with removal of intraconal (60/243 [25%]; p < 0.001), apical (14/29 [48%]; OR, 4.3; p < 0.001), inferior or inferotemporal (41/105 [39%]; OR, 5.5; p < 0.001) masses. Lateral approaches-either with (23/129; 18%) or without (30/71; 42%) osteotomy-were associated with 88% (53/60) of all abnormalities (OR, 4.1; p < 0.001). Where known, the abnormalities improved in 43/50 (86%), although 15/43 (35%) had a persistent tonic pupil.

CONCLUSION: Pupillary abnormalities after excision of OCVMs can occur in up to a quarter of intraconal lesions-particularly those located inferotemporally or inferiorly-and in about a half of apical lesions. Lateral or inferolateral orbital approaches that disrupt the inferior intraconal fat appear to be associated with a higher risk. Most changes resolve or improve markedly, although a third of those affected may have a persistent tonic pupil.