Performance and Safety of a New Ab Interno Gelatin Stent in Refractory Glaucoma at 12 Months.

PURPOSE: To evaluate the intraocular pressure (IOP)-lowering performance and safety of an ab interno gelatin stent (XEN 45 Gel Stent, Allergan plc, Irvine, California, USA), a minimally invasive glaucoma surgery device, in refractory glaucoma. DESIGN: Single-arm, open-label, multicenter clinical study. METHODS: Following mitomycin C pretreatment, the stent was placed ab interno in patients who failed prior filtering/cilioablative procedure or had uncontrolled IOP on maximum-tolerated medical therapy, with medicated IOP ≥20 and ≤35 mm Hg and visual field mean deviation ≤-3 dB. Primary performance outcomes: patients (%) achieving ≥20% IOP reduction from baseline on the same or fewer medications and mean IOP change from baseline at month 12. Procedure-related complications and ocular adverse events (AEs) were assessed. RESULTS: Sixty-five patients were implanted (intent-to-treat/safety population). At 12 months, 75.4% (46/61; observed data) reported ≥20% IOP lowering from baseline on the same or fewer medications. Mean IOP change from baseline was -9.1 mm Hg (95% confidence interval [CI]: -10.7, -7.5) (n = 52; observed data) at 12 months, excluding patients with missing data (n = 4) and those requiring a glaucoma-related secondary surgical intervention (n = 9). Mean medication count decreased from 3.5 (baseline) to 1.7 (12 months). No intraoperative complications or unexpected postoperative AEs were reported. Most AEs were mild/moderate; common AEs included needling (without sight-threatening complications), nonpersistent loss of best-corrected visual acuity, and transient hypotony (requiring no surgical intervention). CONCLUSIONS: The gelatin stent reduced IOP and medication use without raising unexpected safety concerns, offering a minimally invasive surgical option for refractory glaucoma patients.

Considerations of glaucoma in patients undergoing corneal refractive surgery.

Glaucoma patients present a unique set of challenges to physicians performing corneal refractive surgery. Corneal thickness, which is modified during corneal refractive surgery, plays an important role in monitoring glaucoma patients because of its effect on the measured intraocular pressure. Patients undergo a transient but significant rise in intraocular pressure during the laser-assisted in situ keratomileusis (LASIK) procedure with risk of further optic nerve damage or retinal vein occlusion. Glaucoma patients with filtering blebs are also at risk of damage to the bleb by the suction ring. Steroids, typically used after refractive surgery, can increase intraocular pressure in steroid responders, which is more prevalent among glaucoma patients. Flap interface fluid after LASIK, causing an artificially low pressure reading and masking an elevated pressure has been reported. The refractive surgeon's awareness of these potential complications and challenges will better prepare them for proper management of glaucoma patients who request corneal refractive surgery.

Bleb revision for hypotony maculopathy after trabeculectomy.

PURPOSE: To assess the efficacy of a bleb revision technique with regard to improvement in intraocular pressure (IOP) and visual acuity after hypotony maculopathy and to evaluate the influence of duration of hypotony on visual outcome. PATIENTS AND METHOD: : Retrospective review of a series of patients who underwent bleb revision for hypotony maculopathy (IOP less than 6 mm Hg and loss of two or more lines of central vision) following trabeculectomy. Bleb revision included excision of avascular bleb tissue, dissection posteriorly between conjunctiva and Tenon's capsule, and advancement and suturing of the conjunctiva at the limbus. RESULTS: Fourteen patients were included in the study. The average age was 49.8 years (range 18-85) and eight were female. Before trabeculectomy, the mean IOP was 23.2 +/- 11.8 mm Hg, and the visual acuity was 20/30-2 or better in 13 patients and 20/80 in one patient. The mean IOP before bleb revision was 1.07 +/- 0.73 mm Hg, and 12 patients had lost an average of 4.33 +/- 2.96 lines of visual acuity from baseline, while one had count fingers and another had hand motion vision. The final mean IOP after bleb revision was 11.07 +/- 3.08 mm Hg. Compared with visual acuity just prior to bleb revision, 12 patients regained an average best corrected vision of 3.08 +/- 2.67 lines, with seven returning to the pre-trabeculectomy vision level. The duration of hypotony prior to bleb revision was 1 to 24 months (average 8.36 months) with no correlation (correlation coefficient -0.13) between duration and visual outcome. CONCLUSION: Bleb revision for hypotony maculopathy following trabeculectomy is an effective technique for raising IOP and limiting visual loss, which is not influenced by duration of hypotony within the time frame of the study.