Abstract
Purpose :
Elevated intraocular pressure (IOP) is a complication of silicone oil tamponade for retinal detachment repair, and commonly an indication for silicone oil removal (SOR). We performed a retrospective clinical study to examine the IOP lowering effects of and visual outcomes following SOR.
Methods :
Longitudinal data from a university-based retina practice was reviewed from 2010-2015, including patients who underwent silicone oil tamponade for retinal detachment repair with subsequent SOR. Patients receiving a combined SOR and glaucoma procedure were excluded. Patients were separated into two groups based on whether they were on glaucoma medications pre-SOR; paired t-tests were used to determine a change in medications post-operatively within the two groups. Maximum IOP up to 2 months prior to SOR was compared to IOP at <1 month and 3-6 months post-SOR using the paired t-test. Snellen visual acuity (VA) prior to SOR was compared to VA up to 6 months post-SOR using the paired t-test.
Results :
Overall, the mean IOP was lower up to 1 month after SOR compared to pre-op IOP (14.18 vs. 20.18, p=0.0025). The lasting effect of lowered IOP was seen at 3-6 months post-SOR (21.4 pre-SOR vs. 14.3 post-SOR, p=0.01). 12 (36%) of the 33 total patients underwent SOR secondary to elevated IOP (>21 mmHg). In these patients, the mean IOP was lower at both <1 month (31.3 pre-SOR vs. 18.3 post-SOR, p= 0.007) and 3-6 months (31.7 pre-SOR vs. 15.4 post-SOR, p=0.009). The 19 patients who were not using glaucoma medications pre-SOR did not have a change in medications after SOR (0 pre-SOR vs. 0.21 post-SOR, p=0.1). Comparing the 14 patients who were on glaucoma medications pre-SOR, the number of medications post-SOR was not significantly lower (2.7 pre-SOR vs. 1.7 post-SOR, p=0.057). Best corrected VA was not found to be different at 1 month (p=0.57) or 3-6 months (p=0.83) follow up. After 1 month, 28% of all patients achieved VA >20/200. 3-6 months post-SOR, 38% of patients achieved VA >20/200, while 4% of patients achieved >20/40.
Conclusions :
While VA was not significantly improved in long term follow up after SOR, the effect of SOR in lowering IOP among all patients is demonstrated regardless of whether SOR was performed secondary to elevated IOP. This suggests that silicone oil may be sub-clinically present in the anterior chamber in all patients with silicone oil tamponade, with its total removal contributing to decreased IOP.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.