Amir Rosenblatt

Efficacy of Corneal Collagen Cross-Linking for the Treatment of Keratoconus: A Systematic Review and Meta-Analysis.

Purpose: To examine the efficacy of corneal collagen cross-linking (CXL) for the treatment of keratoconus (KCN). Methods: A systemic literature review and meta-analysis of ocular functional and structural parameters of patients with KCN undergoing cross-linking procedures were performed using PubMed and the web of science. A literature search was performed for relevant peer-reviewed publications on population-based studies. Data were analyzed with R software (Meta library), and heterogeneity was assessed with the Cochran Q and I2. A random-effects model was used for high heterogeneity; otherwise a fixed model was used. Sensitivity analysis of particular tested groups was used to explain high heterogeneity. The main outcome measures extracted from the articles were corrected distance visual acuity, uncorrected distance visual acuity, and maximum K. Results: An improvement in visual acuity of 1 to 2 Snellen lines was found 3 months or more after undergoing CXL. Changes were more pronounced in uncorrected visual acuity. Some topography parameters were found to be improved (0.6–1 diopters) 12 to 24 months after CXL. The refractive cylinder improved by 0.4 to 0.7 diopters. Endothelial cell density decreased by 225 cells per square millimeter in the first 3 months and thereafter returned to normal. Corneal thickness was reduced by 10 to 20 &mgr;m in the year following CXL but not after 24 months. No changes in intraocular pressure were noted. Conclusions: CXL is a safe and effective method for halting the deterioration of KCN, while slightly improving visual function.

Vascularization of Irregular Retinal Pigment Epithelial Detachments in Chronic Central Serous Chorioretinopathy Evaluated With OCT Angiography

BACKGROUND AND OBJECTIVE To assess eyes with flat, irregular retinal pigment epithelial detachments (RPEDs) associated with central serous chorioretinopathy (CSCR) for choroidal neovascularization (CNV) using optical coherence tomography angiography (OCTA). MATERIALS AND METHODS Retrospective review of OCTA images of chronic CSCR eyes with irregular RPED (group 1) and regular RPED (controls, group 2) for presence of CNV, subretinal fluid, and intraretinal fluid. Fluorescein angiography was also evaluated for CNV. RESULTS CNV was detected using OCTA in 13 of 31 eyes (41.9%) in group 1 and in one of 18 eyes (5.6%) in group 2 (P = .007). Irregular RPED was a risk factor for CNV (odds ratio [OR] = 12.28; 95% CI, 1.45-104.3). There was no significant difference between detection by OCTA and FA (P = 1.0). Sensitivity and specificity of detection by OCTA were 85.7% and 95.7%, respectively. CONCLUSIONS Irregular RPEDs in chronic CSCR eyes may harbor neovascularization more often than previously thought, which has implications on therapy.

Topical dexamethasone-cyclodextrin nanoparticle eye drops for non-infectious Uveitic macular oedema and vitritis : a pilot study

To evaluate the safety and efficacy of 1.5% dexamethasone nanoparticle (DexNP) drops in eyes with non‐infectious uveitic macular oedema and vitritis.

Outcomes of descemet stripping automated endothelial keratoplasty in patients with an anterior chamber versus posterior chamber intraocular lens.

Purpose: The aim of this study was to assess the implications of a retained anterior chamber intraocular lens (ACIOL) during Descemet stripping automated endothelial keratoplasty (DSAEK) and to compare the outcomes in this group with those in patients who underwent DSAEK and had a posterior chamber intraocular lens (PCIOL). Methods: This is a retrospective cohort study conducted in a tertiary medical center, which compares patients who underwent DSAEK and had a retained ACIOL with patients who underwent DSAEK and had a PCIOL regarding operative and postoperative complications, visual acuity, endothelial cell density, and long-term graft survival. Results: Eleven eyes with an ACIOL and 50 eyes with a PCIOL met the study criteria. No significant differences were found between the groups in terms of operative complications, change in visual acuity, graft survival, and endothelial cell loss. Conclusions: DSAEK in the setting of an ACIOL produced similar results to those of uncomplicated PCIOL cases. Although further studies are needed to gain more accurate information on this subject, it seems that DSAEK can be performed while retaining an ACIOL with favorable results.

Comparison of Ishihara Booklet with Color Vision Smartphone Applications.

Purpose To compare the standard Ishihara booklet with color-vision-testing smartphone applications. Methods A prospective observational diagnostic study on 42 normal trichromats and 38 color-deficient subjects. Patients were presented with three color vision tests in random order: an Ishihara test booklet and two color-vision-testing smartphone applications: Eye2Phone and the Color Vision Test application (CVT app). Sensitivity and specificity of the electronic tests was compared with Ishihara results, and in each one of these applications every plate was individually analyzed for success/failure rate. Results Average age was 42.7 ± 12.9 years. There were 57 males (71.2%). Sensitivity and specificity of each test was 100% (38/38) and 95.2% (40/42) for the Eye2Phone, and 100% (38/38) and 54.8% (23/42) for the CVT app. There was no significant difference between the Ishihara booklet and the Eye2Phone (p = 0.500), with a high kappa measure of agreement (0.950, p < 0.001). The CVT app was significantly different than both other tests (p < 0.001) with a low kappa measure of agreement (0.535 with the Ishihara and 0.575 with the Eye2Phone). Of the 21 tested plates, color-deficient subjects failed 11.8 ± 3.1 plates in the Ishihara booklet and 14.1 ± 2.1 plates in the Eye2Phone (p < 0.001). Significant plate-specific differences for the color-deficient group were found in plate numbers 3, 6, 7, 8, 9, 15, and 16. Both tests were poorly able to give an indication of the specific dichromatism type. The Ishihara booklet was rated more comfortable and clearer than the Eye2Phone in color-deficient subjects. The CVT app was rated lowest for comfort and clarity in both groups. Conclusions Smartphone applications testing for color vision deficiency are readily available; however, users of these apps should be aware that some may have different sensitivity for detection of color vision deficiency compared to Ishihara booklet, limiting their usefulness for clinical use. Therefore, further validation of these applications is required.

Peripheral Blunt Dissection: Using a Microhoe-Facilitated Method for Descemet Membrane Endothelial Keratoplasty Donor Tissue Preparation

Purpose: To describe a modified technique for Descemet membrane donor tissue preparation that facilitates the original Melles stripping technique. Methods: Descemet membrane is prepared using a Rootman/Goldich modified Sloane microhoe, using a blunt instrument as opposed to a sharp blade or needle and begins dissection within the trabecular meshwork. The trabecular tissue is dissected for 360 degrees, and then Descemet membrane is stripped to approximately 50%. A skin biopsy punch is then used to create fenestration in the cornea, which is used to mark an “F.” on the stromal side of Descemet membrane to aid in orientation of the graft. Trephination of the membrane is then performed and stripping is completed. The tissue is stained with 0.06% trypan blue and aspirated into an injector for insertion into the anterior chamber. Results: Before converting to the technique described, 5 of 75 (6.7%) tissues were wasted and 7 of 75 (9.3%) tissues with radial tears were salvaged for use. Since converting to the new technique, only 1 of 171 (0.6%) (P = 0.01) tissues was wasted and 7 of 171 (4.1%) (P = 0.2) tissues with radial tears were salvaged. Conclusions: The peripheral blunt dissection technique offers an improvement over the technique originally described by Melles et al, as the incidence of tissue wastage and tears is lower, it is easy to learn, has low stress, and is reproducible. Combining this with a stromal surface letter mark ensures correct orientation of the tissue against the corneal stroma of the recipient.

Predictability of Biometry in Patients Undergoing Cataract Surgery.

Purpose To compare measurements of axial length (AL), anterior chamber depth (ACD), keratometry (K), and the refractive predictability of the Aladdin and IOLMaster biometry devices in cataract surgery patients. Methods A retrospective observational study of eyes undergoing cataract surgery. Data were retrieved on AL, ACD, and K measurements obtained by the Aladdin and the IOLMaster. Furthermore, the postoperative refractive prediction errors were compared between the devices. Results The study included 127 consecutive eyes of 127 patients undergoing cataract surgery. Mean measurements of AL were not significantly different between the Aladdin (24.18 ± 1.89 mm) and IOLMaster (24.18 ± 1.89 mm) (p = 0.792). Mean K measurements were different between Aladdin (43.84 ± 1.56 D) and IOLMaster (43.97 ± 1.61 D) (p < 0.001). For AL, Aladdin measurements correlated strongly with IOLMaster measurements (r = 0.9997). For K, Aladdin measurements correlated strongly with IOLMaster measurements (r = 0.9912). Fifty-eight of the 127 eyes underwent cataract surgery with a monofocal intraocular lens. For these, mean absolute error (MAE) in predicting refraction relative to the measured postoperative refraction differed between Aladdin (MAE = 0.54 ± 0.40D) and IOLMaster (MAE = 0.49 ± 0.41D) (p = 0.001). After adjustment for the systematic difference in K measurements, the difference in MAE was no longer significant (p = 0.601). The ACD measurements did not differ significantly (p = 0.873) and were well correlated (r = 0.8327). Conclusions A very good correlation was found in AL, K, and ACD measurements between the Aladdin biometer and the IOLMaster. Minimal adjustment for the constant difference in keratometry measurements matched the refractive predictability of both devices.

High‐resolution ultrasound biomicroscopy as an adjunctive diagnostic tool for anterior scleral inflammatory disease

To study high‐resolution ultrasound biomicroscopy (UBM) findings in anterior scleral inflammatory disease and evaluate the efficacy of high‐resolution UBM as an adjunctive diagnostic tool.

Response to letter regarding the publication “Evaluation of the retinal, choroidal and nerve fiber layer thickness changes in patients with toxic anterior segment syndrome”

Dear Editor, We thank Dr. Cheong et al. for their interest in the findings reported in our paper [1], and would like to congratulate them for their solid publications referenced in their letter [2–5]. In our study we evaluated, in a quantitative manner, possible changes in choroidal, retinal, and nerve fiber layer thickness following an occurrence of toxic anterior segment syndrome. We found choroidal thickness (CT) increase in several macular and peripapillary locations, compared with fellow eye measurements. We also found that with time, CT of the study eye decreased compared with baseline study-eye measurements. Calculations of chronological CT change within the study eye did not require correction for AL differences, since they were performed within the study eye only. However, regarding comparisons with the fellow eye – due to the known inverse correlation of axial length (AL) with CT [3, 6–12] we corrected CT measurements of the fellow eye in accordance with the AL difference from the study eye. As pointed out by Cheong et al. in their letter, the correction coefficient for CT according to AL varies widely among published studies (−17.031 to −58.2 μm/mm) [3, 6–12]. Prior to choosing the AL correction coefficient for our study, and in order to select the one most suitable for our cohort, we evaluated all CT studies that provided AL correction coefficients [3, 6–12]. Five studies were of lower relevance to our cohort, and were excluded: two studies that were limited only to eyes with high myopia [7, 12], two studies that had a very young patient cohort (23.0±1.9 and 24.9±2.6 years, respectively) [3, 8], and one study that did not provide a uniform AL correction coefficient for all refractive error ranges [9]. The remaining three studies [6, 10, 11] presented AL correction coefficients that were not substantially different from one another (−22.00, −24.95, and −28.44 μm/mm, respectively). We chose to use the AL correction coefficient (−22.00 μm/mm) given by the study with the largest (79 eyes) cohort of the three [6]. Had we not chosen the study with the largest cohort of the three, but the one with the cohort age most similar to ours (64.6± 17.3 years; range 21–87 years [10]), the AL correction coefficient used would have been −24.95 μm/mm. There is a very small difference of 2.95 μm/mm between those two AL correction coefficients (−22.00 μm/mm vs. -24.95 μm/mm), which is negligible, considering the fact that the average difference in AL between study and fellow eye in our study was only 0.23 mm. This would translate into a change of only 0.68 μm in CT measurements, and therefore, it can be assumed that a choice of any of those two correction coefficients would provide similar results. The findings of Tan et al. [3], which were published in parallel to our study, show that CT exhibits greater rates of variation with AL and spherical equivalent (SE) in the central and inner subfields compared with the outer subfields. These findings are important in the ongoing research of the choroid, and should be applied in future studies in the field of CT. However, although age correction coefficients were calculated in their study, their cohort was relatively young with a narrow age distribution (23.0±1.9 years; range, 21–33 years), and therefore, the AL correction coefficients found in their study might not be applicable to our cohort of much older patients (72.8±8.7 years; range 57–89 years). We feel that further large-scale research is required in this field, to provide * Nir Sorkin nir_sorkin@yahoo.com