Strabismus surgery outcomes in eyes with glaucoma drainage devices

Concurrent adjacent strabismus surgery with glaucoma drainage device placement in childhood glaucomas

BACKGROUND

Determine outcomes of concurrent strabismus surgery with placement of a glaucoma drainage device (GDD) in children.

METHODS

Retrospective review of pediatric patients who underwent simultaneous lateral rectus (LR) muscle surgery with superotemporal GDD placement. Strabismus and GDD success were defined as residual horizontal misalignment < 10 prism diopter (PD) and intraocular pressure (IOP) < 21 mmHg, no visually devastating complications, and no additional IOP-lowering surgeries.

RESULTS

Fifteen eyes of 13 patients (69% male) underwent LR surgery (14 recessions, 1 resection) for exotropia or esotropia simultaneous with GDD placement (13 Baerveldt, 2 Ahmed) at 8.34 ± 5.26 years. Preoperative visual acuity (VA) in operative eye (0.89 ± 0.54) was worse than non-operative eye (0.23 ± 0.44, p = 0.0032). Preoperative horizontal deviation was 38.3 ± 9.4 PD and LR recession was 7.4 ± 1.1 mm. At final follow-up, VA in operative eye (0.87 ± 0.52) was unchanged from preoperative (p = 0.4062). Final IOP was significantly decreased (12.4 ± 4.7 mmHg vs. 31.1 ± 11.4 mmHg, p = 0.0001) as was number of glaucoma medications (2.7 ± 1.7 vs. 1.1 ± 1.3, p = 0.0037). Five (38%) and 9 patients (69%) met criteria for strabismus and GDD success, respectively. Two eyes required tube revision and endoscopic cyclophotocoagulation and 2 eyes had additional strabismus surgery.

CONCLUSIONS

Concurrent strabismus and GDD surgery decreased horizontal deviation and obtained IOP control. It is important to consider correction of strabismus at time of GDD placement to maximize visual development and improve cosmesis in children with glaucoma.

Efficacy and safety of blepharoptosis repair after incisional glaucoma surgery

PURPOSE

There is an increased risk for development of blepharoptosis after incisional glaucoma surgery. Data on safety and efficacy of ptosis repair in this group of patients in limited. The goal of this study is to evaluate outcomes and identify potential risk factors for failure of ptosis repair in eyes with history of incisional glaucoma surgery.

METHODS

A retrospective chart review was performed of all patients who underwent incisional glaucoma surgery, specifically trabeculectomy or implantation of glaucoma drainage device (GDD), and subsequent ptosis repair at a single institution from 2009 to 2019. Ptosis surgery outcomes were compared to a control group who underwent ptosis repair after cataract surgery.

RESULTS

Seventy-eight eyes of 64 patients were included in the glaucoma surgery group. The rate of severe ptosis (margin reflex distance 1 ⩽ 0 mm) among glaucoma surgery patients was higher compared to control (35 of 78 (44.9%) vs 23 of 82 (28.6%). Ptosis repair was successful in 59 of 78 eyes (75.6%), which was similar to control. Risk for revision surgery was increased more than five-fold in the GDD group compared to control. There were no cases of early or late bleb-related complications.

CONCLUSIONS

Ptosis repair can be performed safely in patients after incisional glaucoma surgery. Müller muscle conjunctival resection and external levator advancement are equally effective. Patients with history of GDD should be advised about the potentially increased risk of need for revision surgery.

Removal of a Baerveldt Glaucoma Implant and Fibrous Adhesion for Refractory Mechanical Strabismus

Although strabismus is a well-known complication of glaucoma implant surgery, its surgical treatment is still challenging. We present a case with refractory strabismus after Baerveldt glaucoma implant (BGI) surgery, which was not sufficiently improved by strabismus surgery, but by removal of the BGI and fibrous adhesion. The patient was a 35-year-old woman who had multiple surgeries for secondary glaucoma. She had severe limitations of the movement of her right eye and binocular diplopia in all gaze positions after BGI surgery. Although she underwent two strabismus surgeries, the strabismus was not resolved. The surgery was performed by two specialists in glaucoma and strabismus. The BGI plate and the fibrous capsule were carefully removed. The fibrous tissue involved the muscle bellies of the inferior and particularly lateral rectus (LR) muscles and induced tight and wide adhesion between the muscle bellies and sclera. The adhesion was released after tenotomy at the insertion of the LR muscle, and the LR muscle was additionally resected by 6.0 mm. The ocular position and movement dramatically improved; however, intraocular pressure (IOP) increased immediately after the surgery. Then, Ahmed glaucoma valve implantation was performed 5 days after BGI removal. The IOP decreased and has been controlled. The improvement of ocular position and movement remained 9 months postoperatively and she obtained cosmetic satisfaction without diplopia or worsening of visual acuity. Removal of BGI and fibrous adhesion is a potential option for refractory mechanical strabismus following BGI surgery; however, it is important to prepare additional procedures for the subsequent IOP increase in advance.

Otago Glaucoma Surgery Outcome Study: Examining the Development of Strabismus Causing Diplopia in Patients Who Have Received Molteno Implant Surgery

OBJECTIVE

To evaluate the development of postoperative strabismus causing diplopia in patients who received Molteno implant surgery for the treatment of glaucoma.

METHODS

The Otago Glaucoma Surgery Outcome study (OGSOS) was used to select cases who had undergone Molteno implant surgery to examine the effect on the development of strabismus causing diplopia. Information was collected on treatments provided to correct motility disturbance, and their success, in this retrospective non-comparative study.

RESULTS

32 cases (3.3%) were found to have developed diplopia following the Molteno implant surgery from a total of 977 cases. Of these, the strabismus in 23 cases was described in sufficient detail to permit clinical categorization. Most (19/23) demonstrated an exodeviation, hyperdeviation, or a combination thereof, although 2/6 cases with superonasal plate location demonstrated a hypodeviation. Diplopia generally resolved spontaneously (20/32 cases). Treatment was required in eight cases, usually conservative and successful (6/8 cases), but strabismus surgery was required in two cases, and was unsuccessful.

CONCLUSIONS

This study found a low incidence of diplopia developing post-Molteno implant surgery. Strabismus features suggested a restrictive etiology, and spontaneous recovery was common (62.5%). Surgical correction proved unsuccessful - confirming persistent postoperative diplopia after Molteno implant surgery to be a rare but surgically challenging complication.