Purchase this article with an account.
Tian Xia, Priyal Shah, Kelly Lee, Albert S Khouri; Rate of scleral patch graft (SPG) melt after glaucoma tube shunt surgery: A long term cross sectional study. Invest. Ophthalmol. Vis. Sci. 2017;58(8):5579.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Tube shunt SPG melt causing subsequent tube exposures can lead to complications after glaucoma drainage implantation (GDI). Studies have documented risk factors for tube shunt exposure and techniques for repair. However, limited studies have explored the rate of SPG melt.
Subjects presenting for follow up with history of GDI with SPG at Rutgers New Jersey Medical School between September and November, 2016 were consecutively prospectively enrolled. Standardized SPG slit lamp imaging (8x8mm diffuse beam, neutral density filter, 10x magnification) was performed (HD 12 MP, file size ~0.5 to 1.2MB) to measure percentage of graft surface area melt (GSAM) at different postoperative periods. Data was collected on demographics, presence of comorbid medical/ocular conditions, glaucoma type, ocular inflammation status, prior glaucoma surgeries. Z-test of proportions were performed with significance of p <0.05.
43 eyes of 38 patients (mean age 63 years, 56%female, 44%male) were enrolled. Subject characteristics included 2(5%) aphakic, 29(67%) pseudophakic, 12(28%) phakic; 5(12%) insulin-dependent diabetes (DM), 16(37%) non-insulin dependent DM , 22(51%) no DM; 20(47%) with primary open angle glaucoma, 23(53%) with secondary glaucoma including neovascular and uveitic glaucoma; 10(23%) with previous trabeculectomy with mitomycin C; 5(12%) with dry eyes syndrome; 9(21%) Baerveldt implant, 34(79%) Ahmed implant; 6(14%) with >6 weeks of topical steroid use. Time from surgery was: <3months:8(18.5%), 3-12months:10(23%), 12-24months:8(18.5%), and >24months:17(39.5%) eyes. Average percentage of graft surface area (GSA) remaining were 62.7, 28.6, 34.1, and 14.1, respectively (p <0.05). Proportion of 50% GSA melt was noted at the 4 time period, 25%, 70%, 62.5% and 82.4% (p <0.05). Proportion of 75% GSA melt occurred in 12.5%, 60%, 50%, and 76.4% of grafts, respectively (p <0.05). All grafts had >25% GSA melt at > 2 years. There was no statistical significance comparing proportion of melt by age, history of previous surgery, DM, ocular inflammation status, and type of glaucoma.
Scleral graft melt occurs at a very high rate (100% with 25% area loss after 2 years). The process seems to occur gradually over time and is significantly noted as early as 3 months post GDI. A larger cohort will further improve our understanding of the rate and risks factors of graft melt over time.
This is an abstract that was submitted for the 2017 ARVO Annual Meeting, held in Baltimore, MD, May 7-11, 2017.
This PDF is available to Subscribers Only