Pseudo-Brown syndrome: a potential ophthalmologic sequela after a transcaruncular-transconjunctival approach for orbital fracture repair.

PURPOSE: To prospectively assess the incidence of orthoptic anomalies and, more specifically, the possible development of pseudo-Brown syndrome related to inferior oblique muscle (IO) myotomy after the transcaruncular-transconjunctival approach for orbital fracture repair and its effect on the possible development of annoying diplopia. PATIENTS AND METHODS: We analyzed the clinical data from 14 patients with severe isolated medial wall or combined medial wall/floor fractures treated using titanium meshes placed using a transcaruncular-transconjunctival approach. All patients were assessed with a pre- and postoperative ophthalmologic examination using the following methods: prisms and alternate cover test in all 9 gaze directions, Hess-Weiss coordimetry, Maddox rod screen testing, and Harms wall deviometry. The Bielschowsky head-tilt and a forced duction test were also performed. The patients were classified into the following 2 groups: IO paretic-underaction group and non-IO paretic-underaction group.
RESULTS: Of the 14 patients, 7 (50%) fulfilled the criteria for IO paretic-underaction. All 7 developed double vision limited to the extreme upgaze in adduction. Four patients in the non-IO paretic-underaction group had double vision limited to the extreme upgaze in abduction that was already present preoperatively. Diplopia did not interfere with the daily activities in the patients from either group.
CONCLUSIONS: The present study has demonstrated that IO myotomy associated with the combined transcaruncular-transconjunctival approach can result in orthoptic complications. Moreover, our study has shown that the development of a pseudo-Brown syndrome related to IO underaction was not uncommon but resulted in sequela restricted to a very limited portion of the binocular field of vision.