Pars plana vitrectomy and removal of the internal limiting membrane in diabetic macular edema unresponsive to grid laser photocoagulation.

PURPOSE: To evaluate the effectiveness of pars plana vitrectomy (PPV) with removal of the internal limiting membrane (ILM) in diabetic patients with macular edema unresponsive to grid laser photocoagulation. METHODS: In this randomized controlled study, 20 eyes of 10 patients with diabetic macular edema unresponsive to grid laser photocoagulation were evaluated. PPV with ILM removal was performed randomly in one eye each of 10 patients and taken as the study group; the untreated fellow eyes were taken as the control group. Main outcome measures were foveal thickness changes measured with optical coherence tomography and preoperative and post-operative visual acuity. Mann-Whitney U, Wilcoxon, and chi-square tests were used in statistical analysis. RESULTS: The mean age of the patients was 61.5+/-6 years (range 51 to 71). All patients were followed up for 12 months. In the study group, mean foveal thickness was 391.3+/-91.6 microm preoperatively and 225.5+/-49.4 microm postoperatively (p=0.009). In the control group, mean foveal thickness was 356.2+/-140 microm at baseline and 318.4+/-111.1 microm at 12-month follow-up (p=0.138). Mean decrease in foveal thickness was 165.8+/-114.8 microm in the study group and 37.8+/-71.2 microm in the control group (p=0.016). In the study group, best-corrected log-MAR visual acuity was 0.71+/-0.43 preoperatively and 0.54+/-0.45 postoperatively (p=0.125). In the control group, best-corrected logMAR visual acuity was 0.43+/-0.44 at baseline and 0.59+/-0.55 at 12-month follow-up (p=0.235). In the study group, visual acuity improved by two or more lines in 4 eyes (40%) and remained stable in 6 eyes (60%). In the control group, visual acuity improved by two or more lines in 1 eye (10%) and decreased by two or more lines in 3 eyes (30%). CONCLUSIONS: PPV with ILM removal appears to be an effective procedure for reducing diabetic macular edema unresponsive to grid laser photocoagulation. A further study with a large number of patients is required to assess the effectiveness and safety of this procedure.

25-Gauge transconjunctival sutureless pars plana vitrectomy.

PURPOSE: To evaluate the effectiveness, feasibility, and safety of the transconjunctival sutureless vitrectomy (TSV) system for a vriety of vitreoretinal diseases. METHODS: In this retrospective study, the authors evaluated 71 eyes of 63 patients who underwent pars plana vitrectomy (PPV) with the 25-gauge TSV system. The indications for surgical intervention were diabetic vitreous hemorrhage (29 eyes), diabetic macular edema (14 eyes), macular epiretinal membrane (13 eyes), endophthalmitis (5 eyes), vitreous opacities secondary to Behcet's disease (4 eyes), vitreous hemorrhage secondary to branch retinal vein occlusion (4 eyes), and vitreous hemorrhage secondary to age-related macular degeneration (2 eyes). Epiretinal membrane and internal limiting membrane removal, endolaser photocoagulation, and air-fluid exchange were performed when required. RESULTS: Mean follow-up was 3.6 months (range 1-8 months). Mean overall visual acuity (VA) was counting fingers (range light perception to 0.4) preoperatively and 0.2 (range 0.1 to 0.8) postoperatively (p=0.000). Statistically significant VA improvement was observed in eyes with vitreous hemorrhage, diabetic macular edema, and macular epiretinal membrane. VA improved postoperatively in all eyes with endophthalmitis and vitreous opacities secondary to Behcet's disease. The surgery was completed without conjunctival and scleral suturing in all eyes. Mean intraocular pressure (IOP) was 17.2 mmHg (range 10-26 mmHg) preoperatively, 12.4 mmHg (range 6-24 mmHg) on the first postoperative day, 16.6 mmHg (range 10-33 mmHg) at 1 week, and 15.4 mmHg (range 10-20 mmHg) at 1 month postoperatively. On the first postoperative day, IOP was below 10 mmHg (between 6 and 9 mmHg) in 12 eyes (16.9%). In these eyes, IOP was normalized within 1 week without affecting the visual outcome. Five eyes (7%) had transient increase of IOP controlled by topical antiglaucomatous medications. Vitreous washout using 25-gauge TSV system was performed in two eyes, in which vitreous hemorrhage recurred. CONCLUSIONS: The TSV system was observed to be feasible, effective, and safe for a variety of vitre o retinal diseases. This minimally invasive and completely sutureless (transconjunctival) technique appears to decrease the convalescence period, operating time, and postoperative inflammatory response, and improve patient comfort.