Evaluation of laser power stability of repeatedly used SubCyclo probe in micropulse transscleral cyclophotocoagulation for glaucoma: A step towards sustainable ophthalmic surgery.

PURPOSE: To evaluate the laser power stability of the SubCyclo probe for micropulse transscleral cyclophotocoagulation after repeated use. MATERIALS AND METHODS: This experimental study involved 6 new probes. Each probe was connected to the SubCyclo mode (2,000 mW power, 31.3% duty cycle, and 100 seconds duration) of the Vitra 810 laser delivery system (Quantel Medical, France). Laser power measurements were taken using a calibrated laser power meter (Nova, Ophir Optronics Solutions, Israel) every 10 seconds from 10 to 90 seconds during each of the 40 cycles. Intra-rater reliability was assessed using intraclass correlation (ICC). A linear mixed model for repeated measures and pairwise comparisons with Bonferroni adjustment were used for the analysis. RESULTS: The mean (SD) power outputs of all probes for the first cycle and all cycles were 421.9 (19.7) mW and 436.7 (16.1) mW, respectively. During the first cycle, the mean (SD) laser power gradually decreased from 444.3 (13.4) mW at 10 seconds to 407.3 (17.0) mW at 90 seconds (Fig 3). For all cycles, the power was 446.0 (13.6) mW at 10 seconds and gradually declined to 426.8 (21.0) mW at 90 seconds. Pairwise comparisons revealed significant differences in mean laser power outputs after 16 cycles of repeated use compared to the first cycle. The ICC estimate (95% CI) for intra-rater reliability was 0.96 (0.89, 0.99). CONCLUSIONS: The SubCyclo probe maintains stable laser power outputs throughout repeated use for up to 16 cycles, with a significant increase observed after 16 cycles.

Survival Outcome and Prognostic Factors of Corneal Transplantation: A 15-Year Retrospective Cohort Study at King Chulalongkorn Memorial Hospital.

PURPOSE: To evaluate long-term survival outcomes and determine the prognostic factors of corneal transplantation performed at a tertiary referral hospital in Thailand. DESIGN: A 15-year retrospective cohort study. MATERIALS AND METHODS: One corneal graft per patient was selected; graft failure was defined as graft opacity due to recurrent disease or endothelial cell dysfunction. Kaplan-Meier survival analysis was performed. Median time to failure was compared using the Log rank test. Prognostic factors were identified using the Cox proportional hazards model. RESULTS: We enrolled 704 transplanted grafts. Surgical indications were optical (88.5%), therapeutic (10.2%), and tectonic (1.3%). The most common diagnoses were corneal opacity (25.3%), bullous keratopathy (15.8%), and regraft (14.8%). The overall survival rates at 1, 3, 5, and 10 years were 87.5%, 72.0%, 59.2%, and 41.7%, respectively. Univariate analysis identified age, primary diagnosis, graft size, pre-existing glaucoma, prior lens status, prior intraocular surgery, indication for surgery, donor endothelial cell density, and previous graft rejection as prognostic factors for graft failure. Multivariate analysis revealed three prognostic factors: primary diagnosis of perforation/peripheral ulceration/Mooren's ulcer (hazard ratio [HR]=28.57; 95% confidence interval [CI], 6.32-129.16; P<0.001), active keratitis (HR=24.30; 95% CI, 5.88-100.43; P<0.001), regraft (HR=9.37; 95% CI, 2.27-38.66; P=0.002), and pseudophakic/aphakic bullous keratopathy (HR=7.97; 95% CI, 1.93-32.87; P=0.004); pre-existing glaucoma (HR=1.52; 95% CI, 1.13-2.04; P=0.006); and previous graft rejection (HR=1.95; 95% CI, 1.54-2.48; P<0.001). CONCLUSION: Overall corneal graft survival rate was high in the first postoperative year and decreased after that. Primary diagnosis, pre-existing glaucoma, and previous graft rejection negatively influenced graft survival.

Comparative study of 1 DD and 2 DD radius conventional internal limiting membrane peeling in large idiopathic full-thickness macular holes: a randomized controlled trial.

OBJECTIVE: To compare the surgical outcomes of 1-disc diameter (DD) and 2-DD conventional internal limiting membrane peeling (C-ILMP) in large full-thickness macular holes (FTMHs). MATERIALS AND METHODS: A prospective randomized controlled trial. One hundred patients with large idiopathic full-thickness macular hole (FTMH) were randomized into C-ILMP and extended C-ILMP (EC-ILMP) groups. The primary outcome was closure rate at 6 months after surgery. Secondary outcomes were visual acuity (VA), closure type, consequence of ILMP and complications. RESULTS: The mean symptom duration was 12.19 ± 9.64 months. Mean preoperative VA was 1.25 ± 0.37 logMAR. The average minimum linear diameter was 633.05 ± 129.82 µm and basal linear dimension was 1158.49 ± 249.07 µm. The two groups did not differ in term of demographic data. Closure rate was significantly higher in the EC-ILMP group (76.47% vs. 51.02%, 95% CI 7.24-43.66; p = 0.008). There were also no significant differences in closure type, central foveal thickness, dissociated optic nerve fibre layer detection, or change in fovea-to-disc distance. There were also no significant differences in postoperative VA (p = 0.069) or visual improvement (mean 0.39 ± 0.43 logMAR; p = 0.286). According to subgroup analysis, EC-ILMP resulted in a higher closure rate in patients with chronic FTMH for >6 months, (p = 0.008). Furthermore, EC-ILMP resulted in better anatomical closure and visual result in patients with FTMH with macular hole closure index ≤0.5, p = 0.003 and p = 0.010, respectively. CONCLUSION: Extended C-ILMP yielded a significantly higher closure rate in large FTMHs, but visual outcome did not differ significantly. According to subgroup analysis, extended C-ILMP was more effective in chronic large FTMH with MHCI ≤ 0.5.

The diagnostic accuracy of single- and five-field fundus photography in diabetic retinopathy screening by primary care physicians.

PURPOSE: The aim is to evaluate the diagnostic accuracy of digital fundus photography in diabetic retinopathy (DR) screening at a single university hospital. METHODS: This was a cross-sectional hospital-based study. One hundred and ninety-eight diabetic patients were recruited for comprehensive eye examination by two ophthalmologists. Five-field fundus photographs were taken with a digital, nonmydriatic fundus camera, and trained primary care physicians then graded the severity of DR present by single-field 45° and five-field fundus photography. Sensitivity and specificity of DR grading were reported using the findings from the ophthalmologists' examinations as a gold standard. RESULTS: When fundus photographs of the participants' 363 eyes were analyzed for the presence of DR, there was substantial agreement between the two primary care physicians, κ = 0.6226 for single-field and 0.6939 for five-field photograph interpretation. The sensitivity and specificity of DR detection with single-field photographs were 70.7% (95% Confidence interval [CI]; 60.2%-79.7%) and 99.3% (95% CI; 97.4%-99.9%), respectively. Sensitivity and specificity for five-field photographs were 84.5% (95% CI; 75.8%-91.1%) and 98.6% (95% CI; 96.5%-99.6%), respectively. The receiver operating characteristic was 0.85 (0.80-0.90) for single-field photographs and 0.92 (0.88-0.95) for five-field photographs. CONCLUSION: The sensitivity and specificity of fundus photographs for DR detection by primary care physicians were acceptable. Single- and five-field digital fundus photography each represent a convenient screening tool with acceptable accuracy.