Tear fluid signs associated with filtration blebs, as demonstrated by three-dimensional anterior segment optical coherence tomography

PURPOSE: To determine the clinical features of tear fluid signs associated with filtration blebs via three-dimensional anterior segment optical coherence tomography (3D AS-OCT). METHODS: In total, 152 eyes (130 patients) with glaucoma that underwent trabeculectomy with mitomycin C were evaluated retrospectively. We investigated tear fluid signs associated with filtration blebs, using 3D AS-OCT with custom software, and compared the findings of lower tear meniscus. We also analyzed postoperative intraocular pressure and the bleb parameters of filtration blebs between eyes with and without tear fluid signs. RESULTS: We found tear fluid signs associated with filtration blebs in 45 (30%) of 152 eyes. The mean postoperative intraocular pressure of the eyes with the tear fluid sign in a filtration bleb was significantly lower than that in eyes without the tear fluid sign (P<0.001). Blebs with tear fluid signs have more frequent identifiable filtration openings, greater total height, increased fluid-filled cavity height, and less wall intensity compared with blebs without these signs. CONCLUSION: We identified tear fluid signs in AS-OCT images on or along filtration blebs that depended on bleb morphology. The occurrence of these signs may be related to the presence of functional blebs, which may thereby control postoperative intraocular pressure.