Hypertensive phase and its association with surgical outcomes in Baerveldt implantation

To evaluate the rate of the hypertensive phase (HP) post-Baerveldt implantation and association between HP and surgical outcomes.

This is a retrospective observational study of glaucoma patients who had Baerveldt implantation in 2004 and completed 18 months of follow-up. At 18 months of follow-up, medical records for HP and its associated factors, and surgical outcomes such as rate of failures, intraocular pressure (IOP), numbers of medications administered, and complications were reviewed and identified.

Thirty-seven patients were eligible. Mean (SD) preoperative IOP was 30.5 (7.9) mmHg which significantly lowered to 13.1 (7.0) mmHg post-operation. Mean numbers of medications (SD) significantly decreased from 3.6 (0.7) to 1.3 (1.3). Failure rate at 18 months was 10.8% (4/37 patients). HP was noted in 18/37 patients (48.6%) with the onset between 1 and 3 months post-surgery. Preoperative IOP and one previous glaucoma surgery were associated with presence of HP (p = 0.010, OR 0.82, 95% CI 0.71-0.96 and p = 0.003, OR 26.12, 95% CI 2.95-231.41, respectively). The presence of HP was predictive of postoperative numbers of medications administered (p = 0.001). None of those with HP were from the failure group.

Baerveldt implantation is an effective procedure with high success rate. HP was common after Baerveldt implantation. Preoperative IOP and numbers of previous glaucoma surgery are risk factors for developing HP. Presence of HP can predict whether long-term anti-glaucoma medication(s) are needed or not.