Effect of initial retinal thickness on outcome of intravitreal bevacizumab therapy for diabetic macular edema.

PURPOSE: To investigate whether eyes with diabetic macular edema (DME) and central retinal thickness (CRT) >400 µm had better visual and anatomical outcomes compared to eyes with a CRT <400 µm when treated with intravitreal bevacizumab in a real-world setting. PATIENTS AND METHODS: Patients undergoing intravitreal bevacizumab therapy for DME were identified from the departmental database of a tertiary referral unit. Following the initial injection, a retreatment was performed for any persistent macular edema, unless there had been no previous response to repeated doses. Recorded parameters included visual acuity, CRT on optical coherence tomography (spectral domain optical coherence tomography [SD-OCT]), and SD-OCT characteristics. Comparisons were made between data at baseline and 12 months after the first injection, and differences were tested for statistical significance using the Student's t-test. RESULTS: In all, 175 eyes of 142 patients were analyzed. Patients in group 2 (CRT >400 µm) had significantly more injections than group 1 (CRT <400 µm) (4.0 versus 3.3; P=0.003). Both groups had similar numbers of eyes with preexisting epiretinal membrane and/or vitreomacular traction at baseline. The reduction in CRT was significantly greater in group 2 when compared to group 1 (P<0.0001). In terms of visual gain between baseline and month 12, each gained significantly by a mean of 0.12 logarithm of the minimum angle of resolution units (P=0.0001), but there was no difference between groups 1 and 2 (P=0.99). CONCLUSION: These results do not support a 400 µm baseline CRT cut-off for treating DME with bevacizumab, in contrast to published data on ranibizumab. Our results also indicate that patients with a thicker CRT require more bevacizumab injections, making treatment less cost-effective for these patients. Our results could be used by practitioners to support the use of bevacizumab in DME without applying a CRT cut-off.

Scanning laser polarimetry in eyes with exfoliation syndrome.

PURPOSE: To compare retinal nerve fiber layer thickness (RNFLT) of normotensive eyes with exfoliation syndrome (XFS) and healthy eyes.
 METHODS: Sixty-four consecutive individuals with XFS and normal office-time intraocular pressure (IOP) and 72 consecutive healthy controls were prospectively enrolled for a cross-sectional analysis in this hospital-based observational study. The GDx-VCC parameters (temporal-superior-nasal-inferior-temporal [TSNIT] average, superior average, inferior average, TSNIT standard deviation (SD), and nerve fiber indicator [NFI]) were compared between groups. Correlation between various clinical parameters and RNFLT parameters was investigated with Spearman coefficient. 
 RESULTS: The NFI, although within normal limits for both groups, was significantly greater in the XFS group compared to controls: the respective median and interquartile range (IQR) values were 25.1 (22.0-29.0) vs 15.0 (12.0-20.0), p<0.001. In the XFS group, all RNFLT values were significantly lower compared to controls (p<0.001). However, they were all within the normal clinical ranges for both groups: TSNIT average median (IQR): 52.8 (49.7-55.7) vs 56.0 (53.0-59.3) µm; superior average mean (SD): 62.3 (6.7) vs 68.8 (8.2) µm; inferior average mean (SD): 58.0 (7.2) vs 64.8 (7.7) µm, respectively. TSNIT SD was significantly lower in the XFS group, median (IQR): 18.1 (15.4-20.4) vs 21.0 (18.4-23.8), p<0.001. There was no systematic relationship between RNFLT and visual acuity, cup-to-disc ratio, IOP, central corneal thickness, Humphrey mean deviation, and pattern standard deviation in either group. 
 CONCLUSIONS: Compared to control eyes, polarimetry-determined RNFLT was lower in XFS eyes with normal IOP. Therefore, close monitoring of RNFLT may facilitate early identification of those XFS eyes that convert to exfoliative glaucoma.

24-hour efficacy of the bimatoprost-timolol fixed combination versus latanoprost as first choice therapy in subjects with high-pressure exfoliation syndrome and glaucoma.

AIM: To compare the 24-h intraocular pressure (IOP) control obtained with the bimatoprost-timolol fixed combination (BTFC) versus latanoprost in newly diagnosed, previously untreated exfoliation syndrome (XFS) or exfoliative glaucoma (XFG) patients with baseline morning IOP greater than 29 mm Hg. METHODS: One eye of 41 XFS/XFG patients who met inclusion criteria was included in this prospective, observer-masked, crossover, comparison protocol. All subjects underwent a 24-h untreated curve and were then randomised to either evening administered BTFC or latanoprost for 3 months and then switched to the opposite therapy. At the end of each treatment period, patients underwent a treated 24-h IOP assessment. RESULTS: 37 patients completed the trial. At baseline, mean untreated 24-h IOP was 31.1 mm Hg. Mean 24-h IOP with BTFC was significantly lower than with latanoprost (18.9 vs 21.2 mm Hg; p<0.001). Furthermore, BTFC reduced IOP significantly more than latanoprost at every time point, for the mean peak and trough 24-h IOP (p<0.001). There was no difference, however, in mean 24-h IOP fluctuation between the two medications (3.8 with BTFC vs 4.2 with latanoprost; p=0.161). Both treatments were well tolerated and there was no statistically significant difference for any adverse event between them. CONCLUSIONS: As first choice therapy in high-pressure, at-risk exfoliation patients, BTFC controlled mean 24-h IOP significantly better than latanoprost monotherapy.