Motility Changes and Diplopia After Baerveldt Glaucoma Drainage Device Implantation or After Trabeculectomy.

PURPOSE

The purpose of this study was to quantify any diplopia and motility changes after the implantation of a Baerveldt glaucoma implant (BGI) or after trabeculectomy (TE).

METHODS

We analyzed 51 patients with a BGI and 52 patients with a TE from a prospective cohort study. To quantify any diplopia, we asked patients about the presence of diplopia at 1 year after surgery. To quantify any ocular motility changes, we measured ductions in eight gaze directions, the patients' ocular alignment and their fusion range before and 1 year after surgery.

RESULTS

In the BGI group, 14 patients (28%) experienced diplopia compared with one patient (2%) in the TE group ( < 0.001). Duction changes were more commonly observed in the BGI group (35%) than in the TE group (19%). In the BGI group, ductions were mostly restricted in elevation (13%; < 0.001), in abduction (13%), in elevation in 25° adduction (13%; = 0.044), and in elevation in 25° abduction (25%; < 0.001). In 32% of the patients, their near horizontal ocular alignment shifted, notably in exodirection ( = 0.04). The fusion range decreased significantly in the horizontal direction (-12.6° ± 10.3°, mean ± standard deviation; = 0.01).

CONCLUSIONS

BGI surgery was significantly associated with postoperative diplopia and impaired eye motility (reduced ductions), mostly present in abduction, elevation, elevation in 25° adduction, and elevation in 25° abduction. Even without impaired ductions, diplopia could come about.

TRANSLATIONAL RELEVANCE

By studying diplopia across glaucoma patients prospectively with diplopia questionnaires and extensive orthoptic measurements, we gain better insight into its occurrence.