Differences in Corneal Biomechanics in Nonpenetrating Deep Sclerectomy and Deep Sclerectomy Reconverted into Trabeculectomy

Modification of Corneal Biomechanics and Intraocular Pressure Following Non-Penetrating Deep Sclerectomy

Changes in the cornea can influence outcomes in patients with primary open-angle glaucoma (POAG). We aimed to evaluate the relevance of changes in corneal biomechanics and intraocular pressure (IOP) in patients undergoing non-penetrating deep sclerectomy (NPDS) with the Esnoper V2000 implant^® (AJL Ophthalmic S.A., Gasteiz, Spain). We included 42 eyes of 42 patients with POAG scheduled for NPDS with the Esnoper V2000 implant. Biomechanical properties were measured by Ocular Response Analyzer^® G3 (ORA; Reichert Inc., Depew, NY, USA). Corneal hysteresis (CH), corneal resistance factor (CRF), corneal compensated IOP (IOPcc), and Goldmann-correlated IOP (IOPg) were measured the day before surgery and on day 1, 7, and 30 and 2 and 3 months after surgery. CH initially increased, fell below the presurgical value at 30 days after the surgery, and increased again at 2 and 3 months. CRF, IOPcc, and IOPg decreased on the first day after surgery, then followed a trend of increasing but stayed below pre-surgery levels. All values reached statistical significance. While observed changes in corneal biomechanics after NPDS and Esnoper V2000 implant were significant, more studies are needed if we are to understand their influence on corneal biomechanics and their clinical relevance in POAG.

CO2 laser-assisted sclerectomy surgery in the treatment of open-angle glaucoma in Chinese patients

PURPOSE

To evaluate the efficacy and safety of CO2-Laser Assisted Sclerectomy Surgery (CLASS) with 5-fluorouracil (5-FU) in treating open-angle glaucoma (OAG) in Chinese patients. Methods: This was a retrospective, uncontrolled, interventional case series. All patients from 2016 to 2017 who received CLASS were recruited in this study. The primary outcome was the change in intraocular pressure (IOP) and the number of IOP-lowering medications over a 12-month follow-up period. Adverse events were evaluated as secondary outcomes. Results: Data were collected from forty-two eyes of 31 patients. The average preoperative IOP was 31.33 ± 7.60mmHg. The mean percentage of IOP reduction from baseline at postoperative months (POM) 1, 3, 6, 9, and, 12 were 48.1% ± 24.6%, 51.4% ± 19.3%, 51.2% ± 17.2%, 50.9% ± 15.0%, 49.2% ± 16.3%, respectively (all P < 0.001). The number of glaucoma medications decreased from a baseline of 3.02 ± 0.81 to 0.05 ± 0.22, 0.10 ± 0.37, 0.12 ± 0.40, 0.17 ± 0.44, and 0.24 ± 0.58 at POM 1, 3, 6, 9, and 12, respectively (all P < 0.001). At POM 1, 3, 6, 9, and 12, complete success rates were 66.7%, 73.8%, 76.2%, 69.1%, and 71.4%, respectively. At POM 1, 3, 6, 9, and 12, qualified success rates were 71.4%, 82.0%, 85.3%, 83.3%, and 90.5%, respectively. Major postoperative complications include peripheral iris synechia, iris incarceration, and anterior chamber shallowing. Conclusions: CLASS with 5-FU shows safety and efficacy for decreasing IOP and the number of IOP-lowering medications over a 12-month follow-up period. It could be an alternative treatment for patients with OAG.

Effect of trabeculectomy and Ahmed glaucoma valve implantation surgery on corneal biomechanical changes

PURPOSE

To evaluate alterations in corneal biomechanical properties before and 6 months after conventional trabeculectomy (TRAB) and Ahmed glaucoma valve (AGV) implantation.

METHODS

Thirty-nine eyes of 39 patients were evaluated retrospectively. Complete ophthalmological examinations including evaluation of corneal biomechanical properties using the Ocular Response Analyzer were performed before and after 6 months postoperatively. A mean of four measurements for corneal hysteresis (CH), corneal resistance factor (CRF), Goldmann correlated intraocular pressure (IOPg), and corneal compensated intraocular pressure (IOPcc) was recorded. The participants had undergone trabeculectomy or shunt surgery as the first surgical procedure for glaucoma treatment of uncontrolled IOP with maximum antiglaucoma eyedrops.

RESULTS

There were 20 eyes of 20 patients in trabeculectomy group and 19 eyes of 19 patients in AGV implantation group. There was no significant difference between two groups in terms of sex, age, eye laterality, lens status, antiglaucoma drug usage, preoperatively measured Mean Deviation of Humphrey Visual Field Analyzer, CH, CRF, IOPcc, and IOPg (p > 0.05). CH and CRF increased significantly after shunt surgery (p < 0.001). CH increased in trabeculectomy group postoperatively (p < 0.001); however, CRF showed a small amount of decrease, but this reduction was not statistically significant (p > 0.05). CH and CRF showed higher increase after AGV surgery than trabeculectomy surgery (p < 0.05). There was no significant correlation between IOP changes and CH-CRF changes in both TRAB and AGV groups (p > 0.05).

CONCLUSION

According to our results, surgical technique differences may have an impact on postoperative corneal biomechanical outcomes. AGV surgery offers better corneal biomechanical results than standard trabeculectomy in 6-month follow-up.