Abstract
Purpose :
For trabeculectomy surgery and many other glaucoma procedures, the literature suggests that eyes with a secondary glaucoma have a lower success rate than those with a primary glaucoma and those who are pseudophakic may have a higher failure rate.
The purpose of our study was to determine if secondary glaucoma diagnosis and pseudophakic lens status effect future IOP control following Glaucoma Drainage Device (GDD) surgery.
Methods :
A retrospective, single-center, single-surgeon comparative review of 170 eyes with a diagnosis of either a Primary Glaucoma (POAG, Pseudoexfoliation or Pigmentary glaucoma) (n=111) or a Secondary Glaucoma (neovascular, uveitic, traumatic, secondary angle closure or open angle glaucoma) (n=59) undergoing a GDD procedure. Fifty-four eyes were phakic and 116 eyes were pseudophakic.
The mean intraocular pressure (IOP) and number of glaucoma medications were obtained pre-operatively and post-operatively for up to seven years. Demographics and additional glaucoma surgeries were documented. Statistical comparisons were performed with t-tests and chi-squared tests.
Results :
Baseline pre-operative IOP was 26.2 ± 8.5 mmHg and 34.0 ± 10.4 mmHg in the Primary and Secondary Glaucoma groups, respectively (p<0.0001) (Figure 1). Mean pre-operative glaucoma medication use was 3.3 versus 3.1 medications, respectively (p=0.20). Post-operatively, there was no significant difference between primary and secondary eyes in mean IOP from years one (1) to year 7 (Figure 1) and there was no significant difference in medication use any time point. Additional glaucoma surgery (second GDD or Cyclophotocoagulation) was required in 12% of primary glaucoma eyes and 7% of the secondary glaucoma eyes (p= 0.51).
Baseline pre-operative IOP was 31.7 ± 10.2mmHg vs 27.6 ± 9.5 mmHg in the phakic and pseudophakic groups, respectively (p= 0.01) (Figure 2). There was no significance difference between phakic and pseudophakic eyes in mean IOP or medication use from year 1 to year 7. Additional glaucoma surgery was required 18% of phakic eyes and 9% of pseudophakic eyes (p=0.23).
Conclusions :
Unlike trabeculectomy, GDD surgery appears to have equal chance for success regardless of primary or secondary glaucoma diagnosis and lens status.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.