Persistent Hypotony and Annular Ciliochoroidal Detachment After Microhook Ab Interno Trabeculotomy

Abstract

Précis: Creation of a cyclodialysis cleft can be a mechanism of ciliochoroidal detachment (CCD) and associated persistent hypotony after microhook ab interno trabeculotomy (μLOT). Aims: To report persistent hypotony after μLOT, a minimally invasive glaucoma surgery (MIGS). Subjects and Methods: This observational case series included 4 consecutive cases (3 men, 1 woman; mean age, 48.8±15.1 y) of persistent hypotony that developed after μLOT between May 2015 and March 2018. The patients’ data and surgical results were obtained from the medical charts. Results: All patients had open-angle glaucoma (2 juvenile, 1 primary, and 1 pigmentary) and were myopic (axial lengths, >24 mm). Two patients had undergone previous refractive surgery. μLOT alone was performed in 2 cases and combined with cataract surgery in 2 cases. In all cases, hypotony below 5 mm Hg was recorded 1 day postoperatively and sustained. In all cases, ultrasound biomicroscopy showed an annular CCD; communication between the anterior chamber and suprachoroidal space was detected in 3 of 4 cases. The hypotony resolved in 3 of the 4 cases from 2 to 8 months postoperatively, that is, spontaneously in 2 cases (cases 1 and 4) and after sulfur hexafluoride gas injection into the anterior chamber in 1 case (case 2). CCD resolution accompanied remarkedly high intraocular pressure, which required filtration surgeries. The incidence of persistent hypotony was 0.7% (4/547 eyes). Conclusions: After MIGS, persistent hypotony because of CCD rarely occurs. Increased uveoscleral outflow because of LOT or creation of a cyclodialysis cleft by traction of the pectinate ligament can be a mechanism of CCD development. Young age and myopia can be risks for cyclodialysis cleft formation and hypotony maculopathy after MIGS.

Comparison of outflow facility before and after the microhook ab interno trabeculotomy

“…Sato et al reported that CCDs detected by AS-OCT developed in 21 of 44 eyes (48%) within 7 days after 360-degree suture LOT; the CCDs resolved in 19 eyes within 1 month and in two eyes by 3 months [17]. We previously reported four cases of hypotony that persisted from the early post-operative periods [18]. Thus, CCDs generally are not rare events after MIGS surgery and seem to be associated with IOP reductions immediately postoperatively [18].…”

Midterm Results of Microhook ab Interno Trabeculotomy in Initial 560 Eyes with Glaucoma

“…In the current case series, persistent hypotony subsequent to ciliochoroidal detachment (CCD) developed in four eyes. As discussed previously [ 40 ], increased uveoscleral outflow due to LOT [ 41 ] or the creation of a cyclodialysis cleft by traction of the pectinate ligament [ 40 ] can be a mechanism of CCD development. Akagi et al reported that a CCD detected by anterior-segment OCT developed in 14 (42%) of 33 eyes 3 days after a Trabectome procedure; the CCD persisted in four eyes (12%) at 1 month and resolved by 3 months [ 42 ].…”

XEN-related hypotonous maculopathy from iatrogenic cyclodialysis cleft treated with argon laser gonio-cyclopexy

“…Another case,11 similarly reports good long-term prognosis results with direct cyclopexy surgery, following failed medical and laser treatment of cyclodialysis cleft secondary to cataract extraction, combined with an AIT with Trabectome. A recent case series12 documented treatment after sulphur hexafluoride gas injection was efficacious.…”