Purpose: To evaluate the utility of the Visante OCT in the follow-up of filtering surgery.
Material: and methods: In this study, we evaluated 38 filtering blebs in 31 patients following trabeculectomy (4) and nonpenetrating deep sclerectomy (NPDS). In 11 cases, mitomycin C was used during surgery. In patients who underwent NPDS, a collagen implant was placed within the scleral site in eight eyes and seven eyes had goniopuncture during follow-up. All patients had complete ophthalmologic examination with morphological evaluation of the bleb and intraocular pressure measurement as well as Visante OCT evaluation.
Results: The trabeculectomy site as well as the trabeculodescemetic membrane (in NPDS), the scleral flap, the conjunctival flap, the iris, and the relationship between these structures were analyzed. Functioning blebs had a hyporeflective and irregular conjunctival tissue associated with a route for aqueous humor under the scleral flap from the anterior chamber toward the subconjunctival space. This filtration route was also observed within nonfunctioning encapsulated blebs. Flat and encapsulated nonfunctioning blebs had dense and hyperreflective conjunctival tissue. In the particular case of nonfunctioning flat blebs, there was no route for aqueous humor filtration under the scleral flap.
Conclusion: The Visante OCT is a simple and noninvasive imaging technique with good resolution, allowing the analysis of morphologic changes occurring in eyes after filtering surgery.