Demographic, clinical and tomographic characteristics of pellucid marginal degeneration patients in South Egyptian population.

PURPOSE: To retrospectively evaluate the demographic, clinical, and tomographic characteristics of pellucid marginal degeneration (PMD) patients in South Egypt. METHODS: This study was retrospective cross-sectional, including all patients who attended and sought refractive surgery at Sohag Center for Corneal and Refractive Surgeries, Sohag, South Egypt, between October 2016 and October 2020, and had a diagnosis of PMD. It included cases of PMD at different stages. Cases with PMD were diagnosed by the two authors (experienced in corneal refractive surgery), combining both slit-lamp biomicroscopy findings and corneal tomography. RESULTS: Out of the 2534 patients attending the Sohag Center for Corneal and Refractive Surgeries (between October 2016 and May 2020) seeking correction of their refractive errors, 24 patients were found to fit in the diagnosis of PMD. Forty-three eyes of the 24 patients were diagnosed with PMD. The topographic patterns ranged from horizontal bow tie (against the rule astigmatism) being the least presenting, followed by crab claw, then butterfly pattern. CONCLUSION: PMD is a separate entity of the ectatic corneal spectrum that can easily be misinterpreted as Keratoconus. Topographic and tomographic patterns cannot solely diagnose PMD as they should be enforced by slit-lamp findings.

Clinical profile and demographic distribution of pellucid marginal corneal degeneration in India: A study of 559 patients.

PURPOSE: The aim of this study was to describe the clinical profile and demographic distribution of pellucid marginal corneal degeneration (PMD) in patients presenting to a multitier ophthalmology hospital network in India. METHODS: This cross-sectional hospital-based study included 2,470,793 new patients presenting between September 2012 and September 2020 (~8 years period). Patients with a clinical diagnosis of PMD in at least one eye were included as cases. The data were collected using an electronic medical record system. RESULTS: Overall, 559 (0.02%) new patients were diagnosed with PMD. The prevalence rates were 0.004% in children (age <16 years) and 0.03% in adults. The majority of patients were males (70.13%) with the bilateral affliction (77.1%). The mean age of the patients was 37.91 ± 13.19 years. The majority (30.23%) of the patients were between 31 and 40 years of age. A significant number of patients were from higher socioeconomic status (93.74%) and from the urban region (45.08%). Of the 990 eyes, the most common clinical signs were ectasia/thinning (58.99%), corneal scar (17.47%), and corneal hydrops (1.01%). The majority of the eyes (87.97%) were managed with either spectacles or contact lenses. Among those who had surgical intervention, collagen cross-linking was the most performed procedure (5.25%) followed by cataract surgery (4.14%). CONCLUSION: PMD is a rare disease affecting patients seeking eye care in India. It commonly affects adult males and is bilateral in nature. The disease progression is slow and usually occurs beyond 3 years. Conservative management is more common than surgical intervention.

Prevalence of granular corneal dystrophy type 2-related TGFBI p.R124H variant in a South Korean population.

Purpose: Granular corneal dystrophy type 2 (GCD2) is an autosomal dominant disorder and is associated with the arginine to histidine substitution at codon 124 (p.R124H) of the TGFBI gene. Although TGFBI p.R124H is known to be the most common corneal dystrophy-related pathogenic variant, there are few data on the frequency of this variant in the South Korean population. Methods: In total, 2,060 anonymous DNA samples from a public umbilical cord blood bank were tested for the TFGBI p.R124H variant using real-time PCR. Results: Six of the 2,060 samples [0.29%; 95% confidence interval (CI), 0.12-0.67%] were heterozygous for the TGFBI p.R124H variant. The prevalence of the GCD2-related TGFBI p.R124H variant in this population was estimated to be 291.3 per 100,000 [95% confidence interval (CI), 118.5-667.0]. Conclusions: To our knowledge, this is the largest study that has estimated the prevalence of the GCD2-related TGFBI p.R124H variant in South Korea.

Genotype and Long-term Clinical Course of Bietti Crystalline Dystrophy in Korean and Japanese Patients.

PURPOSE: To investigate the genotype and long-term clinical phenotype of patients with Bietti crystalline dystrophy (BCD) in Korea and Japan. DESIGN: Retrospective case series. PARTICIPANTS: We analyzed 62 patients with clinical features of BCD who harbor pathogenic biallelic CYP4V2 variants in their homozygote or compound heterozygote. METHODS: Data were collected from patient charts, including age, best-corrected visual acuity (BCVA), Goldmann perimetry results, fundus photography, OCT findings, fundus autofluorescence results, and electroretinography findings. We compared the clinical course of the patients with homozygous c.802-8_810de117insGC [exon7del], the most common mutation in the East Asian population, with those of the patients with other genotypes. MAIN OUTCOME MEASURES: Best-corrected visual acuity, visual field (VF), and their changes during follow-up. RESULTS: The mean age at the first visit was 55.2 years, with a mean follow-up of 7.1 years. The mean BCVAs at the first and last visits were 0.28 logarithm of the minimum angle of resolution (logMAR) and 0.89 logMAR, respectively. In genetic testing, c.802-8_810de117insGC was detected in 86 of 124 alleles of the patients, and 36 patients were homozygous for this mutation. The age, BCVA, VF area, central foveal thickness, and abnormal hypoautofluorescent area at either the first or last visit were not different between the exon7del homozygotes and the others. The mean BCVA changes per year were 0.089 logMAR in the exon7del homozygotes and 0.089 logMAR in the others. An age- and gender-adjusted linear regression analysis showed no association between the exon7del homozygote status and the rate of vision loss. Characteristic crystalline deposits in the posterior pole were generally observed in younger patients and disappeared over time along with progressive retinochoroidal atrophy. CONCLUSIONS: Patients with BCD and a homozygote for c.802-8_810de117insGC accounted for more than 50% of this cohort of Korean and Japanese patients, and the clinical effect of this deleterious variant was not severe in the spectrum of CYP4V2 retinopathy.

Progression of diffuse chorioretinal atrophy among patients with high myopia: a 4-year follow-up study.

AIMS: To investigate the progression pattern of diffuse chorioretinal atrophy (DCA) among Chinese participants with high myopia. METHODS: This is a longitudinal, non-interventional study. Participants with high myopia, defined as ≤-6 diopters spherical power, were included and followed up for 4 years, and underwent cycloplegic autorefraction, best-corrected visual acuity (BCVA) and fundus photography examinations. Newly established DCA, enlargement of existing DCA and development of other lesions of myopic maculopathy were regarded as DCA progression. RESULTS: Of the 484 participants with a mean age of 21.5±12.7 years (range, 6.8-69.7 years), 68 eyes (14.0%) showed DCA progression, with 88 lesion changes. The first appearance of DCA was identified in 21 eyes (23.9%). Of 88 eyes with DCA at baseline, 47 eyes (53.4%) showed progression, with 67 lesion changes, including 45 eyes (67.2%) with enlargement of DCA, 17 (25.3%) with a first appearance of lacquer cracks, 4 (6.0%) with development of patchy chorioretinal atrophy and 1 (1.5%) with increased numbers of lacquer cracks. Longer axial length (p<0.001), baseline DCA (p=0.005) and baseline DCA closer to the fovea (p=0.013) predicted DCA progression. Eyes had poorer BCVA at the follow-up if DCA was enlarging (p<0.001) or DCA was closer to the fovea at baseline (p=0.028) after adjusting for age,gender and cataract. CONCLUSION: Approximately half of the participants with DCA had progression over a 4-year follow-up. Enlargement and newly developed DCA were common progression patterns. Larger areas of DCA and foveal involvement with DCA could be indicators of a worse BCVA later.

Diagnostic Criteria for Terrien Marginal Degeneration: Nordic Terrien Degeneration Study.

PURPOSE: To refine the diagnostic criteria for Terrien marginal degeneration (TMD) based on experience in 3 Nordic countries. METHODS: This is a retrospective, multicenter, hospital-based cross-sectional study of 49 eyes of 29 white patients in tertiary referral centers in Finland, Sweden, and Denmark from 1998 to January 2018. The median follow-up was 3 years. Symptoms, best corrected visual acuity, astigmatism, corneal thickness, curvature and cavities, stage, and progression were analyzed. RESULTS: TMD was diagnosed equally likely between 15 and 86 years of age (median, 47 years). Twenty patients (69%) had bilateral disease, and 62% were men. Seventeen patients (59%) had symptoms including blurred vision and ocular surface disease symptoms without inflammatory signs. Eight patients (28%) had slightly reduced corneal sensitivity. Median best corrected visual acuity was 20/25 (range, 20/16-20/200) and astigmatism was 2.6 diopters (D) (range, 0-10) with a mean progression of 0.41 D per year (range, 0-5.4). Age and astigmatism were not correlated. All eyes had peripheral vascularization, lipid deposits, and hyperreflectivity throughout thinned peripheral stroma and its anterior edge. The thinning progressed in 15 patients (52%). Of 26 patients, 8 (31%) had single or confluent paralimbal intrastromal cavities, most commonly superiorly. By Süveges classification, the stage was 2 (92%) or 3 (8%). Minimum corneal thickness and corneal curvature were loosely associated, leading to different stages in Wang classification in 34 eyes (69%). CONCLUSIONS: TMD is defined by peripheral corneal thinning, superficial neovascularization, lipid deposition at the leading edge, absence of ulceration and inflammation, and frequently cavitation. The most sensitive way to follow its progression is anterior segment optical coherence tomography.

Clinical Profile and Demographic Distribution of Corneal Dystrophies in India: A Study of 4198 Patients.

PURPOSE: To describe the clinical profile and demographic distribution of corneal dystrophy in patients presenting to a multitier ophthalmology hospital network in India. METHODS: This cross-sectional hospital-based study included 2,151,584 new patients presenting between March 2012 and December 2019 (∼8 year period). Patients with a clinical diagnosis of corneal dystrophy in at least 1 eye were included as cases. The data were collected by using an electronic medical record system. RESULTS: Overall, 4198 new patients (0.20%) were diagnosed with corneal dystrophy. The prevalence rates were 0.19% in children (age < 16 years) and 0.20% in adults. Most patients were women (51.86%). The mean age of the patients was 43.61 ± 21.39 years. Most patients (18.79%) were between 61 and 70 years of age. The most common anatomical location of the dystrophy was endothelium (51.71%), followed by stroma (43.55%) and Bowman membrane/epithelium (4.73%). The most common corneal dystrophy was Fuch endothelial corneal dystrophy (41.89%). Most eyes had mild or no visual impairment (43.43%). Of the 8193 eyes, 998 eyes (12.18%) underwent a corneal surgery. Among those who underwent surgical intervention, endothelial keratoplasty was the most commonly performed surgical procedure (52%), followed by penetrating keratoplasty (22%). CONCLUSIONS: Corneal dystrophy is a rare disease, affecting patients seeking eye care in India. Endothelial dystrophies were the most common, followed by stromal dystrophies. Among the stromal dystrophies, macular dystrophy was the most common. At initial presentation, visual impairment was mild to moderate in most patients, and surgical intervention was needed in 12.18% of the eyes during the study period.

Changing Trends in Penetrating Keratoplasty Indications between 2011 and 2018 - Histopathology of 2123 Corneal Buttons in a Single Center in Germany.

Purpose: To analyse the changing trends in penetrating keratoplasty indications between January 2011 and December 2018, at the Department of Ophthalmology, Saarland University Medical Center, Homburg/Saar, Germany. Patients and Methods: This is a retrospective review of 2123 corneal buttons of 1776 patients (1993 eyes, 56.0% males, age at the time of surgery 57.6 ± 18.7 years), who underwent penetrating keratoplasty (PKP) between January 2011 and December 2018. The classification was performed based on histological analysis and using the priority scheme of Brady et al., supplemented by a group of "failed endothelial keratoplasty grafts". Our groups were the following: pseudophakic or aphakic bullous keratopathy, regraft, failed endothelial keratoplasty graft, acute necrotizing and ulcerative keratitis, keratoconus, Fuchs' dystrophy, corneal dystrophy other than Fuchs', corneal scars and other diagnoses. Results: Between 2011 and 2018, keratoconus was the leading indication for PKP in 455 (21.5%) cases, followed by acute necrotizing and ulcerative keratitis in 384 (18.1%), regraft in 367 (17.3%), corneal scars in 350 (16.5%), pseudophakic or aphakic bullous keratopathy in 225 (10.6%), Fuchs' dystrophy in 194 (9.1%), other diagnoses in 64 (3.0%), corneal dystrophy other than Fuchs' in 52 (2.4%), and failed endothelial keratoplasty graft in 32 (1.5%) cases. Conclusions: With the introduction of posterior lamellar keratoplasty, keratoconus remains the leading PKP indication in our center with excimer laser-trephination on a routine basis. A trend towards increasing numbers can be observed regarding acute necrotizing and ulcerative keratitis patients and regrafts. However, the incidence of Fuchs' dystrophy decreased dramatically within PKP patients, with the introduction of posterior lamellar keratoplasty.

Chorionic villus sampling: 10 years of experience in a University referral center.

OBJECTIVES: The purpose of this study was to estimate our center-specific CVS-related miscarriage rate. METHODS: This is an observational retrospective study of women submitted to a CVS in our hospital, between January 1st, 2007 and December 31st, 2016. Maternal and pregnancy characteristics, procedure details, genetic results and pregnancy outcomes of all patients were collected. The FMF miscarriage risk algorithm was used to estimate our population expected risk of miscarriage. To establish the procedure-related risk of miscarriage, we compared the observed with the expected miscarriage rate. RESULTS: We had a total number of 1523 women with a singleton pregnancy who did a CVS over the 10-year period. The mean maternal age was 34 years old; the majority of the women was Caucasian, multiparous and had a spontaneous pregnancy. The most common indication for CVS was a high-risk result in the 1st trimester combined screening test. The karyotype was normal in 72,7% of cases, 11,1% were T21 and 7,2% were T13 or T18. In the study group, 33 women were diagnosed with a fetal demise, 435 had a TOP and there were 4 intrauterine deaths and 34 miscarriages. The rate of miscarriage in our population was 3,2% and the expected patient specific risk for miscarriage was 3,0%. There was no statistical significance between the two miscarriage rates p = 0,705. CONCLUSION: In our study the risk of miscarriage in the CVS group was not significantly different from that the expected patient specific risk (3.2 % vs 3%, p = 0.7). The procedure-related risk of miscarriage was 0,2%, similar to the rates describe in the literature. An accurate risk of pregnancy loss should be used when counseling women for CVS to allow an informed decision.

DIFFUSE CHORIORETINAL ATROPHY IN CHINESE HIGH MYOPIA: The ZOC-BHVI High Myopia Cohort Study.

PURPOSE: To explore the associations between diffuse chorioretinal atrophy (DCA) and age, sex, axial length, spherical equivalent, and best-corrected visual acuity (BCVA) among highly myopic eyes. METHODS: This study included right eyes of 857 bilaterally highly myopic individuals from the ZOC-BHVI Cohort Study. Participants underwent examinations, including BCVA, ocular biometry, autorefraction, and color fundus photography. An Early Treatment Diabetic Retinopathy Study grid was applied on the fundus photographs to evaluate the location of DCA, which was graded into four categories (D0-D3). The characteristics and ocular biometry were compared between participants' eyes with and without DCA. RESULTS: Diffuse chorioretinal atrophy was found in 177 (20.6%) eyes. The proportion of participants with DCA in age groups of 7 to 11, 12 to 18, 19 to 39, and ≥ 40 years old was 20.9%, 9.2%, 23.1%, and 52.9%, respectively. The proportion of DCA significantly increased with longer axial length and worse myopic spherical equivalent. Eyes with DCA had poorer BCVA (Snellen visual acuity 20/36, logarithm of minimal angle of resolution 0.26 ± 0.25) than those without DCA (Snellen visual acuity 20/23, logarithm of minimal angle of resolution 0.06 ± 0.14) (P < 0.001). The BCVA gradually declined as the lesion got closer to the fovea (P for trend < 0.001). CONCLUSION: The proportion of DCA increased with older age, longer axial length, and more myopic spherical equivalent. Diffuse chorioretinal atrophy is a vision-threatening complication of high myopia where BCVA gradually worsens with foveal involvement.

Coexistence of Congenital Hereditary Endothelial Dystrophy and Fuchs Endothelial Corneal Dystrophy Associated With SLC4A11 Mutations in Affected Families.

PURPOSE: To evaluate parents of probands affected with autosomal recessive congenital hereditary endothelial dystrophy (CHED) for clinical signs of Fuchs endothelial corneal dystrophy (FECD) and to determine the genotypes of the SLC4A11 gene in the probands and their parents. METHODS: This study involved 9 patients affected with CHED from 8 families. The parents of such probands were examined to investigate for possible signs of FECD although they did not present with any visual complaints. Blood samples were collected after obtaining consent, from all 9 cases and the parents of each proband, for genetic analysis. Genomic DNA isolated from blood leukocytes was used for genetic analysis. Screening of the coding regions of the SLC4A11 gene for mutations was carried out by standard procedures using polymerase chain reaction (PCR) amplification and sequencing. Sequences were checked against the human SLC4A11 reference sequence to detect alterations and in normal control samples available in the laboratory. RESULTS: The probands had characteristic signs of CHED, whereas one of the parents of each of the probands showed early signs of FECD, characterized by the presence of guttae in the central cornea corroborative with the diagnosis of FECD, and were otherwise asymptomatic at that time. The CHED-affected probands were homozygous for various SLC4A11 mutations, and their parents were heterozygous for the same. The mutations included missense mutations in 6 probands and nonsense mutations in 2 cases. CONCLUSIONS: Heterozygosity for SLC4A11 mutations in the parents of children with autosomal recessive CHED appears to be a risk factor for the development of FECD in these cases.

Multiple phototherapeutic keratectomy treatments in a Chinese pedigree with corneal dystrophy and an R124L mutation: a 20-year observational study.

BACKGROUND: To investigate the efficacy and safety of repeated phototherapeutic keratectomies (PTKs) during long-term treatment for corneal dystrophy (CD) in a Chinese pedigree carrying the R124L mutation in TGFBI. METHODS: This was a retrospective review of 20-year medical and genetic records involving five CD patients (10 eyes) from one pedigree. During this period, PTK was conducted for an eye when best-corrected distance visual acuity (BCDVA) reached > 1.0 (LogMAR), due to either primary or recurrent opacities in the cornea. All PTKs were performed by 193-nm excimer laser with or without creation of epithelial flaps. For each eye, routine measurements were conducted for the number of PTKs during follow-up, mean time to recurrence, and BCDVA pre- and post- every PTK (measurements within 3 months from each PTK). Corneal thicknesses measured after the last PTK and at the last visit were analyzed, and subjective satisfaction was assessed. RESULTS: Gene testing revealed an R124L mutation in TGFBI. During 19.60 ± 1.78 years of follow-up, PTKs were conducted twice for three eyes, three times for six eyes, and four times for one eye. After each PTK, effective visual acuity was maintained for 3.60 ± 1.12 years before significant recurrence. BCDVA improved significantly postoperatively than preoperatively for the first PTK for each eye (p < 0.001), as well as the second (p < 0.001) and third one (p < 0.001). After the last PTK and at the final visit, the thinnest corneal thickness was 371.50 ± 56.47 µm and 358.40 ± 101.11 µm, respectively. The average subjective satisfaction score was 8.60 ± 0.89. CONCLUSIONS: Multiple repeated PTKs were effective and safe in a long-term study of CD patients with an R124L mutation in TGFBI.

Recurrent corneal erosion syndrome.

Recurrent corneal erosion syndrome (RCES) is a disorder characterised by a dysfunctional epithelial ecosystem. It often begins after trauma, or in the setting of epithelial basement membrane degeneration or dystrophy. Historically, RCES has been understood as a structural derangement of the anterior corneal architecture. More recently, studies have demonstrated the important role of neuropeptides in corneal homoeostasis. Thus, RCES may also be understood as a disorder of corneal epithelial cell biology. Management of RCES can be challenging, but newer therapies have demonstrated improved efficacy for this condition. This review examines the aetiology and pathogenesis of RCES, and provides an update on current and emerging treatment modalities for the management of this disorder.

Prevalence and risk factors of myopic maculopathy in rural southern China: the Yangxi Eye Study.

AIMS: To evaluate the prevalence of myopic maculopathy among participants aged 50 years and older in rural southern China. METHODS: Population-based, cross-sectional study. Subjects were recruited using cluster sampling from Yangxi County, Guangdong Province, China from August to November in 2014. Non-cycloplegic autorefraction and fundus photography were performed on all of the participants. Myopic maculopathy was graded based on fundus photographs using the International Classification of Myopic Maculopathy. RESULTS: Among 5825 individuals who participated (90.7% response rate), a total of 4469 participants with gradable fundus photographs for myopic maculopathy and automated refractive data were included in this study. The mean age of these participants was 65.50±9.70 years. The crude prevalence of myopic maculopathy was 1.4% (62/4469; 95% confidence interval [CI] 1.0% to 1.8 %) and age-standardised prevalence was 1.2% (95% CI 1.1% to 1.2%). Diffuse chorioretinal atrophy, patchy chorioretinal atrophy, macular atrophy, lacquer cracks and staphyloma were observed in 43 (1.0%), 3 (0.1%), 1 (0.1%), 15 (0.3%) and 8 eyes (0.2%), respectively. Myopic maculopathy was more common in eyes of older participants (OR 1.07; 95% CI 1.03 to 1.11) and more myopic spherical equivalence (OR 1.69; 95% CI 1.57 to 1.84). CONCLUSION: The prevalence of myopic maculopathy was low among the rural southern Chinese population. Diffuse chorioretinal atrophy was the most common retinal finding among Chinese myopes.

[Recurrent Corneal Erosions in Epithelial Corneal Dystrophies]. / Rezidivierende Hornhauterosion bei epithelialen Hornhautdystrophien.

The corneal epithelium is the most important structure of the ocular optical system. Recurrent corneal erosions can result from inflammation, trauma, degeneration and dystrophies. Epithelial basement membrane dystrophy (EBMD), epithelial recurrent erosion dystrophy (ERED) and Francheschetti and Meesmann's epithelial corneal dystrophy (MECD) can all - besides other signs and symptoms - result in more or less frequent corneal erosions. The pathomechanisms involved however are different. In EBMD, corneal erosions are facultative and clinical signs are often subtle. Aberrant basement membrane structures are associated with thinning of the epithelium and can be clinically identified as maps or fingerprints. In ERED, recurrent corneal erosions are - predominantly in the first decades of life - always present. A defect in the COL17A1 gene results in a dysfunctional hemidesmosome. In MECD, punctate corneal erosions are less frequent and result from intraepithelial microcysts which open spontaneously onto the ocular surface. Usually lubricants, therapeutic contact lenses and sometimes epithelial debridement and phototherapeutic keratectomy are the mainstay for treating corneal erosions in these three dystrophies.

Prevalence of stromal corneal dystrophies in Lahore.

To determine the prevalence of Stromal Corneal Dystrophies (SCDs) in patient from Lahore hospitals. The study was performed between November, 2014 to July 2015 at the Layton Rahmatullah Benevolent Trust Hospital, Mughal Hospital, Mayo Hospital and General Hospital, Lahore. For the clinical evaluation of SCD by ophthalmologists examination of cornea was done by biomicroscopy, specular microscopy, topography, keratometry, orbscan and far visual acuity. Fifty cases of SCDs were recognized from Lahore, matching to hospital prevalence of 0.4%. The variables examined were age, gender, main complaint, corneal thickness, intraocular pressure and far visual acuity. SCDs are predominant in age group of 40-50 years. SCDs are more in male (n=30) as compared to females (n=20). Careful clinical evaluation, genotyping, governmental approval and subsequent development of human clinical trials of possible therapies and treatments should be taken to continue making improvement and effective control of SCDs.

National survey of pellucid marginal corneal degeneration in Japan.

PURPOSE: A national survey was conducted in Japan to analyze the clinical characteristics of pellucid marginal corneal degeneration (PMD). METHODS: A questionnaire was sent to all members of the Japan Cornea Society requesting demographic and clinical findings on PMD patients who had been examined between 2008 and 2010. The presence of band-shaped peripheral corneal thinning, detected by slit-lamp biomicroscopy or by a pachymetric map, was set as the diagnostic criterion of PMD. RESULTS: Most of the participating facilities relied on either slit-lamp biomicroscopy or corneal topography as diagnostic tools for the detection of PMD. Data on 347 patients (579 eyes) were returned from the participating facilities for analysis, among which 162 eyes in 84 men and 24 women, with a median onset age of 37 years, met the PMD criteria. Of the 108 patients (162 eyes) with classical PMD, unilateral involvement was found in 25 % of patients (27 eyes). In 17 of the 27 eyes for which topographic findings for the contralateral eye were available, seven eyes were either keratoconus or had a suspected diagnosis of keratoconus. An association with allergic disease was found in 24 eyes (22.2 % of patients). Approximately half of the patients had 1.0 or better spectacle-corrected distance visual acuity, and only 5 % showed 0.1 or worse. The mean keratometric value was 45.7 diopters. On corneal topography, 100 eyes (61.7 %) showed the topographic "crab-claw pattern," and the remaining eyes showed other patterns, including inferior steepening (22.2 %) and an irregular pattern (10.5 %). CONCLUSIONS: We conducted the largest clinical survey of PMD to date and found a male predominance, a relatively high prevalence of unilateral involvement, and associated allergic diseases.

Risk of Band Keratopathy in Patients with End-Stage Renal Disease.

This study is a retrospective, nationwide, matched cohort study to investigate the risk of band keratopathy following end-stage renal disease (ESRD). The study cohort included 94,039 ESRD on-dialysis patients identified by the International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM), code 585 and registered between January 2000 to December 2009 at the Taiwan National Health Insurance Research Database. An age- and sex-matched control group comprised 94,039 patients selected from the Taiwan Longitudinal Health Insurance Database 2000. Information for each patient was collected from the index date until December 2011. In total, 230 ESRD patients and 26 controls had band keratopathy (P < 0.0001) during the follow-up period, indicating a significantly elevated risk of band keratopathy in the ESRD patients compared with controls (incidence rate ratio = 12.21, 95% confidence interval [CI] = 8.14-18.32). After adjustment for potential confounders including sarcoidosis, hyperparathyroidism, iridocyclitis, and phthisis bulbi, ESRD patients were 11.56 times more likely to develop band keratopathy in the full cohort (adjusted HR = 11.56, 95% CI = 7.70-17.35). In conclusion, ESRD increases the risk of band keratopathy. Close interdisciplinary collaboration between nephrologists and ophthalmologists is important to deal with band keratopathy following ESRD and prevent visual acuity impairments.

Identification of CYP4V2 mutation in 36 Chinese families with Bietti crystalline corneoretinal dystrophy.

Bietti crystalline corneoretinal dystrophy (BCD) is an inherited eye disease that is most common in the Chinese. It is caused by a mutation in the CYP4V2 gene. In this study, 43 Chinese BCD families were recruited; most patients manifested the characteristic phenotype of BCD, with 2 families initially misdiagnosed with retinitis pigmentosa. Five patients in our cohort presented with BCD and choroidal neovascularization (CNV), and 1 patient presented with typical BCD and abnormality in the terminals of both fingers and toes. A total of 17 pathogenic mutations involving 68 alleles were identified from 36 families using targeted exon sequencing and Sanger sequencing; we achieved a diagnostic rate of approximately 84%. Fifteen families were found to carry homozygous mutations, 17 families carried compound heterozygous mutations, and 4 families carried a single heterozygous mutation. Of the mutations identified, four variants c.802-8_810del17bpinsGC, c.802-8_810del17bpinsGT, c.992A > C (p.H331P), and c.1091-2A > G accounted for 71% of the mutations identified in CYP4V2. These mutations were hotspots in Chinese populations for BCD. Five among them were novel and predicted to be disease-causing, including c.65T > A (p.L22H), c.681_4delTGAG (p.S227Rfs*1), c.802-8_810del17bpinsGT, c.965_7delAAG (p.321delE), and c.994G > A (p.D332N). No apparent correlation between genotype and phenotype was identified. Our findings broaden the spectrum of CYP4V2 mutations that cause BCD and the phenotypic spectrum of the disease in Chinese families. These results will be useful for the genetic diagnosis of BCD, genetic consultation, and gene therapy in the future.

Salzmann's Nodular Degeneration.

Salzmann's nodular degeneration (SND) is a rare, noninflammatory, slowly progressive degenerative disease of the cornea that is characterized by the appearance of nodular bluish gray opacities that vary in number and size. It is usually bilateral; most commonly occurring in people aged 50-60 years old, with a female preponderance; and often associated with a history of prior corneal inflammation. The clinical features usually depend on the location of the nodules. Generally, the nodules of SND are bluish white to gray in color, 1-2 mm in size, and round, conical or prismatic in shape. The overlying Bowman's layer is usually absent from the nodular areas and is partially replaced by granular Periodic Acid Schiff-positive eosinophilic material resembling the basement membrane. Diagnostic investigations include ultrasonic pachymetry, anterior segment optical coherence tomography, ultrasound biomicroscopy, and confocal microscopy. The majority of patients respond well to conservative management with topical lubricants; severe cases may require surgical intervention. The various surgical modalities described include superficial keratectomy, which may be combined with phototherapeutic keratectomy and keratoplasty. Various modifications of these procedures include the use of alcohol-assisted epithelial delamination, intraoperative mitomycin-C or amniotic membrane transplantation to make the procedure easy, reduce the risk of recurrence and improve postoperative comfort. Recurrences are rarely reported; overall, the visual prognosis following treatment is optimal.