Solar retinopathy: a new setting of red, green, and blue channels

Purpose: To introduce a new color imaging technique using improved settings of red, green, and blue channels for improved delineation of retinal damage in patients with solar retinopathy. Method: A retrospective case series of patients with poor vision secondary to solar retinopathy were analyzed. All patients underwent visual acuity, refraction, and dilated fundus examination. A spectral domain–optical coherence tomography of the macula and color fundus imaging using optimized red, green, and blue color setting was performed. Patients were reviewed over a 6-month period. The data were analyzed for statistical significance using an independent t test and a receiver operating characteristic curve. Results: In total, 20 eyes of 10 patients were included between 2009 and 2017. The mean age was 24.9 ± 18.1 years. Best corrected visual acuity at first consultation was 0.78 ± 0.11 and after 6 months was 0.83 ± 0.09. Spectral domain–optical coherence tomography demonstrated retinal abnormalities at the myoid zone, ellipsoid zone, and the outer segment of photoreceptors. Receiver operating characteristic curve analysis showed an improving effect (area under the curve = 0.62; 95% confidence interval = 0.42–0.79). The color channels parameters, which improve visualization of the lesions were found to be 67-0.98-255 for the R-guided setting, 19-0.63-121 for the B-guided setting, and 7-1.00-129 for the G-guided setting. The ideal red, green, and blue setting was in 24-0.82-229. Conclusion: The use of a new setting of red, green, and blue channels could improve the diagnosis and monitoring of solar retinopathy, hence improving patient care

Genetic linkage studies of a North Carolina macular dystrophy family

Background and objective: North Carolina macular dystrophy (NCMD) is a very rare autosomal dominant hereditary disease. Up to date there are three types of NCMD described and consequently named macular dystrophy, retinal: MCDR1, MCDR2 and MCDR3. The aim of this study was to perform linkage and copy number variation analysis for the family affected by NCMD followed by the selected candidate gene sequencing. Materials and methods: This study concerned a 3-generation, non-consanguineous Latvian family with NCMD. Genome-wide scan, copy number variation and non-parametric linkage analysis was performed. Analysis resolved the locus of interest to the 5p15.33 region. Two of the genes, iroquois homeobox 2 (IRX2) and iroquois homeobox 4 (IRX4), were selected and sanger sequencing was performed. Results: Linkage analysis indicated a region on chromosome 5 for the analyzed family, corresponding to a genetic locus previously described for MCDR3 (5p15-p13). Chromosomal aberrations were not identified in the affected family members. An upstream intron variant (NM_001278634: c.-139G > A (rs6876836)) in IRX4 gene segregated with NCMD phenotype in the analyzed family. Conclusions: It is unlikely to be the causative mutation of NCMD due to its high minor allele frequency 0.3532. Therefore, the role of IRX2 and IRX4 genes in the pathogenesis of NCMD has not been proved. Considerable variability in visual acuity between individuals of the same age group in all the families examined was noted. No overlap between NCMD grade and family generation was seen in the family described in the present study

Descemet Membrane Endothelial Keratoplasty in Pseudophakic Bullous Keratopathy: Outcomes and Evidence-Based Suggestions

The purpose of the study was to determine clinical outcomes of Descemet Membrane Endothelial Keratoplasty (DMEK) in patients with Pseudophakic Bullous Keratopathy (PBK). The study was conducted at a tertiary referral center. This was a retrospective case series. Pseudophakic eyes having undergone DMEK surgery for Pseudophakic Bullous Keratopathy was considered the object of study. The examination implied the analysis of best corrected visual acuity (BCVA or CDVA), endothelial cell density (ECD), intraocular pressure (IOP), intraoperative and postoperative complications and a follow-up in 1, 3, and 6 months. For the purposes of the study, 25 pseudophakic eyes with PBK were examined. One month after the surgery patients  reached a BCVA of 0.49±0.08(M±SD), after 3 months - BCVA of 0.65±0.12(M±SD), and a BCVA of 0.78±0.17 (M±SD) in the last follow-up in 6 months after the surgery (P<0,001). The mean ECD after one month was 1661±133 (M±SD) cells/mm2, after 3 months - 1591±124 (M±SD) cells/mm2, and during the last control in 6 months -1579±128 (M±SD) cells/mm2. The graft detachment rate was 12% (3 cases). Hypertension was observed in one eye (4%), necessitating partial air elimination through a corneal wound within the first hours after the surgery. DMEK may give excellent visual results in Pseudophakic eyes without increasing the risk of complications when compared to Descemet Stripping Automated Endothelial Keratoplasty (DSAEK) and Penetrating Keratoplasty (PKP). Anatomic repair after DMEK is associated with improved corneal clarity and BCVA