Abstract
Purpose :
To compare long term surgical outcomes and complications of pars plana (PP) tube implantation with conventional anterior chamber (AC) tube implantation.
Methods :
Records of patients undergoing glaucoma tube shunt surgery at a single institution between 2007-2015 were retrospectively reviewed. Eyes were matched on primary glaucoma diagnosis and patient age. Only eyes with more than 12 months of follow-up data were included. Demographics and baseline characteristics as well as treatment outcomes were recorded.
Results :
Sixty-four eyes that underwent PP glaucoma tube placement were compared against 64 eyes that underwent AC tube placement with either an Ahmed (82.8% in the PP group and 76.6% in the AC group) or a Baerveldt implant (17.2% in the PP group and 21.9% in the AC group). Mean follow-up was 43.3 + 24.0 months for the PP group and 35.4 + 16.8 months for the AC group (p=0.03). Preoperative mean IOP was 28.0 + 12.0 mmHg in the PP group and 32.8 mmHg + 12.4 mmHg in the AC group (p=0.04). Preoperative mean number of glaucoma medications was 2.9 + 1.0 in the PP group and 2.7 + 0.7 in the AC group (p=0.30). At all postoperative time points, the mean IOP and mean number of medications did not differ significantly between groups. Postoperative mean IOP in the PP group was 16.0, 16.0, 14.9, 19.0, and 18.0, and in the AC group was 16.0, 16.0, 17.0, 15.0, and 18.0, at the 12-, 24-, 36-, 48-, and 60-month follow-up, respectively (p>0.05 at all time points). Surgical success was defined as an IOP between 6 and 21 mmHg, no additional glaucoma surgeries performed, and at least light perception vision. Success rates at latest follow-up were similar between groups, with 85.9% success in the PP group and 81.3% success in the AC group. In the PP group, 8 eyes underwent a subsequent glaucoma surgery and 1 eye did not reach the therapeutic IOP range. In the AC group, 11 eyes underwent a subsequent glaucoma surgery and 1 eye did not reach the therapeutic IOP range despite undergoing subsequent glaucoma surgery. In the PP group, there were 19 adverse events (10 diplopia, 6 hypotony, 2 vitreous hemorrhage, 1 tube erosion). In the AC group there were 17 adverse events (7 hypotony, 4 vitreous hemorrhage, 3 diplopia, 3 corneal decompensation).
Conclusions :
Long-term PP placement of glaucoma tube shunts continues to control IOP and yields similar rates of surgical success to conventional AC placement.
This is an abstract that was submitted for the 2017 ARVO Annual Meeting, held in Baltimore, MD, May 7-11, 2017.