Purpose
Canaloplasy, utilizing superior conjunctiva and sclera, could potentially compromise successful dissection and long-term success of a future trabeculectomy. This paper investigates the circumstances and incidence of canaloplasy failures and the success of subsequent trabeculectomy with ExPress mini shunt.
Methods
A retrospective review was preformed investigating the total number of patients requiring trabeculectomy with ExPress shunt following canaloplasty, preformed at one center, over a four-year period. Patient’s age, sex, type of glaucoma, and preoperative characteristics, including intraocular pressure (IOP), number of glaucoma drops, and visual acuity were analyzed. The time to canaloplasty failure, response to Nd:Yag goniopuncture, IOP, and subsequent trabeculectomy success were evaluated. Final IOP, vision, and glaucoma drop requirements were recorded.
Results
A total of 417 patients with a previous canaloplasty were found over the four-year period. A total of 21 trabeculectomies with ExPress shunt were preformed in patients with a previously failed canaloplasty. This represents an incidence of 5%. Patient demographics included an average age at the time of canaloplasty of 70.9 years, preoperative IOP of 26.2, and 2.4 glaucoma drops. Average time to failure was 229 days (69 to 405 days). Nd:Yag goniopuncture was performed at an average of 77 days postoperatively (21 to 215 days). Time from goniopuncture to trabeculectomy was an average of 121 days (43 to 207). The average preoperative IOP prior to trabeculectomy with ExPress shunt was 34 mmHg on an average of 2.3 drops. The final average IOP with an average follow-up of 10 months was 13.5 mmHg using an average of 0.2 drops.
Conclusions
In this series the failure rate of canaloplasty was low. After review of the literature, this study demonstrates for the first time that, in those patients requiring trabeculectomy with ExPress shunt, the previous canaloplasy surgery did not prevent subsequent success.
Keywords: 568 intraocular pressure •
765 wound healing •
735 trabecular meshwork