Abstract
Purpose: :
To evaluate possible risk factors, management options, clinical course and outcomes in eyes with endophthalmitis associated with glaucoma drainage implant (GDI) exposure.
Methods: :
A retrospective study of 218 subjects who underwent GDI implantation at Kresge Eye Institute from 1998 to 2009 was performed. Subjects with GDI exposure were identified and divided into 2 groups based on whether or not they developed endophthalmitis. Binary multiple logistic regression analysis was performed to evaluate possible risk factors. Treatment methods, clinical course and outcomes were evaluated.
Results: :
Twenty-three (10%) of 218 eyes had conjunctival erosion and tube exposure. Of these, 18 met inclusion criteria. The mean age of patients was 69.7 years. The mean interval between GDI surgery and tube exposure was 10.1 months. All 18 patients were treated prophylactically with topical antibiotics. Seven patients (38.9%) developed endophthalmitis (group 1), within a mean of 2.3 months from GDI exposure. All group 1 patients were treated with intravitreal antibiotics; 5 had GDI removal and 2 had wound revision. Eleven patients had GDI exposure without endophthalmitis (group 2); 6 had subsequent wound revision and 5 patients had GDI removal. Mean number of prior ocular surgery involving conjunctiva was 1.9 in group 1 and 1.7 in group 2 (p=0.6). In group 1, visual acuity (VA) improved from 20/300 (mean, pre-op) to 20/200 (mean, final, p=0.59) and IOP improved from 26 (mean, pre-op) to 14 (mean, final, p=0.01). In group 2, VA was stable from CF pre-op to final visit (p=0.55); IOP improved from 38 (mean, pre-op) to 18 (mean, final, p=0.003). There was no significant difference in the change in VA (p=0.34) or IOP (p=0.40) between the 2 groups over time. Using binary multiple logistic analysis, the variables of age, sex, race, diabetes or systemic hypertension, glaucoma type, valve and graft type, number of prior ocular surgeries, time between implant and exposure, and time between exposure and repair were not related to development of endophthalmitis.
Conclusions: :
While endophthalmitis is a rare complication of GDI surgery, GDI exposure is a major risk factor for late infection. Age, sex, race, morbidity due to DM and HTN, glaucoma type, valve and patch graft type, time to GDI exposure, interval between exposure and repair, and number of prior ocular surgeries were not found to be risk factors for the development of endophthalmitis. Meticulous examination of the tube site should be performed at every visit. Prompt surgical revision of an exposed GDI is recommended.
Keywords: wound healing • endophthalmitis • anterior segment