Strabismus surgery in the setting of glaucoma drainage devices in the pediatric population

Purpose: To evaluate outcomes of strabismus surgery performed subequent to or concomitant with glaucoma drainage device (GDD) implantation for refractory childhood glaucoma. Methods: The medical records of children who underwent strabismus surgery after or concomitantly with GDD implantation were reviewed retrospectively. Included were surgeries with motility and alignment data measured preoperatively and ≥3 months postoperatively. The following data were collected: demographics, visual acuity, glaucoma diagnosis, GDD type/location, pre- and postoperative sensorimotor/alignment measurements, and surgical details. Motor success was defined as ≤10^Δ horizontal and ≤4^Δ vertical residual heterotropia postoperatively. Results: A total of 25 children were included: 11 in the post-GDD group and 14 in the concomitant-GDD group. In the former, peri-GDD capsule dissection was required in 9 of 11 patients (82%). All cases had preoperative motility restriction or intraoperative scarring. Mean preoperative deviation (26.7^Δ ± 14.6^Δ) decreased by 41% postoperatively, with improved alignment in 7 patients (64%). No patients met strict motor alignment criteria for success. In the concomitant-GDD group, mean preoperative deviation (28.5^Δ ± 10.0^Δ) decreased by 39% postoperatively, with improved alignment in 11 of 14 patients (79%). Four patients (29%) met strict criteria for success. There were no surgical complications in either group. Conclusions: Strabismus surgery in eyes with existing or planned GDDs for childhood glaucoma usually improves alignment but often does not result in success based on strict motor alignment criteria. Eyes with childhood glaucoma pose surgical technical challenges related to small orbits and exuberant GDD capsule–muscle scarring and postoperative challenges of poor vision and limited binocular function, that likely limit succcess.(Figure presented.)(Figure presented.)