Frequency of bleb manipulations after trabeculectomy surgery

Aim: To quantify the type and frequency of postoperative bleb manipulations undertaken after modern glaucoma surgery. Methods: Bleb manipulations were recorded after trabeculectomy surgery on 119 consecutive patients with at least 1 year of follow- up. The type of intervention and time after surgery were recorded. Statistical analysis identified success rates at various intraocular pressure ( IOP) cut-off definitions and identified factors that increased the risk for bleb manipulation. Results: In all, 78.2% of trabeculectomies were followed by some form of bleb manipulation. Almost 49% of blebs underwent massage and a similar number required at least one suture removal, 31.1% required at least one 5- fluorouracil ( 5- FU) injection and 25.2% required at least one needling and 5- FU injection. The median time to the first intervention for massage, suture removal, 5- FU injection, and needling and 5- FU injection were 1, 14, 14 and 43 days, respectively. IOP measurements were higher at all follow- up time points in the intervention group. Failure to achieve specific IOP target pressures was also generally poorer in the 5- FU, and needling and 5- FU intervention groups. Conclusions: Postoperative intervention is a frequent occurrence after modern glaucoma surgery. This requires intensive postoperative follow- up and is a labour- intensive undertaking. Despite interventions in our group of patients, IOP in the intervention group was always higher than in the group that required no intervention.