Purpose
To assess and evaluate the course and medical treatment of intra-ocular pressure (IOP) after pars plan vitrectomy (PPV) with silicone oil injection (SOI) for different vitreoretinal conditions.
Methods
This is a 5-year prospective study. A total of 260 eyes operated for different vitreoretinal conditions and who had completed a minimum of 6 months follow-up were included in this study. Main outcomes measures were anterior segment examination, IOP measurement by aplanation, fundus exam, number and duration of glaucoma medications needed. Preoperative, intraoperative, postoperative and demographic parameters were also evaluated to determine their predictive value in the increase of IOP.
Results
The indications for PPV with SOI were rhegmatogenous retinal detachment (RRD) (70.8%; 184 of 260), proliferative diabetic retinopathy (PDR) (15.8%; 41 of 260), trauma (5.8%; 15 of 260), macular hole (6.5%; 17 of 260) and others (1.1%; 3 of 260). Overall, 122 of 260 eyes (47%) developed elevated IOP (predefined as IOP > 21 mmHg) after PPV with SOI at 5 days median (range 1day-3 years), whereas 138 eyes (53 %) did not have any. The onset of increased IOP was early (≤ 1 week), intermediate (1 week-6 months) and late (> 6 months) in 74 (60.7%), 37 (30.3%) and 11 (9.0%) of eyes respectively. By stratifying our results according to the different vitreoretinal conditions, 97 (52 %) of the RRD group, 11 (27%) of the PDR group, 7 (47%) of the trauma group and 7 (41%) of the macular hole group raised their IOP postoperatively. IOP was controlled in 104 (85%) of 122 eyes with medical treatment alone within a median duration of 5 months (range 4 days- 4 years). Medical therapy reduced the IOP from a mean ± SD of 26.35 ± 6.55 mmHg before treatment to 18.15± 5.92, 3 months following treatment (p=0.001). 18 (9%) needed chronic use of medical treatment to control their IOP after removal of SO.
Conclusions
Our study provides summary data on IOP course after vitreoretinal surgery for different etiologies. The group RRD seems to have the highest rate of IOP elevation, but without reaching a statistically significant difference. High myopia was the only predictive factor for high IOP, while diabetes was found to be a protective factor against IOP elevation.
Keywords: 762 vitreoretinal surgery •
568 intraocular pressure •
688 retina