Long-term results of trabeculectomy in eyes that were initially successful

A number of published case series provide short-term and intermediate success rates for the surgical treatment of glaucoma with trabeculectomy. There is little information, however, regarding long-term outcomes that extend beyond 10 years. Therefore, we conducted a retrospective study to determine the long-term outcome of eyes that had successful trabeculectomy surgery at 1 year (IOP < 21 mmHg, or lowering by 33% if preoperative IOP was < 21 mm Hg) and had been followed up for at least 10 years. We found 40 such eyes. With respect to IOP control, 83% were still considered to be successful at 5 years, 73% at 10 years, but only 42% at 15 years. Ten percent required additional glaucoma surgery by 5 years, 25% by 10 years, and 58% by 15 years. Forty percent of the eyes had cataract surgery by the time of the last follow-up examination. It appears that there is a significant late failure rate of trabeculectomy in eyes that were initially successful.