A Cross-sectional Analysis of 556 Eyes Entering the Homburg Aniridia Centre.

PURPOSE: Congenital aniridia is a severe malformation of almost all eye segments. In addition, endocrinological, metabolic, and central nervous systems diseases may be present. In order to develop better treatment options for this rare disease, an aniridia center must be established. The purpose of this work is to summarize ophthalmic findings of aniridia subjects examined at the Department of Ophthalmology, Saarland University Medical Center in Homburg. METHODS: Our retrospective single-center study included patients who underwent a comprehensive ophthalmic examination through the head of the KiOLoN ("Kinderophthalmologie", Orthoptics, Low Vision and Neuroophthalmology) Unit of the department between June 2003 and January 2022. Data at the first examination time point have been included. RESULTS: Of 286 subjects, 556 eyes of (20.1 ± 20.1 years; 45.5% males) were included. There was nystagmus in 518 (93.7%) eyes, and strabismus in 327 (58.8%) eyes. There were 436 (78.4%) eyes with age-appropriate axial length, 104 (18.7%) eyes with microphthalmos, and 13 (2.3%) eyes with buphthalmos. There was iris malformation with atypical coloboma in 34 eyes (6.1%), more than 6 clock hours of iris remnants in 61 eyes (10.9%), less than 6 clock hours of iris remnants in 96 eyes (17.2%), and complete aniridia in 320 (57.5%) eyes. The patients were graded according to the following aniridia-associated keratopathy (AAK) stages: Stage 0 (96 eyes [17.2%], no keratopathy), Stage 1 (178 eyes [32.0%]), Stage 2 (107 eyes [19.2%]), Stage 3 (67 eyes [12.0%]), Stage 4 (62 eyes [11.1%]), Stage 5 (45 eyes [8.0%]). There was secondary glaucoma in 307 (55.5%), macular hypoplasia in 395 (71.4%), and congenital optic nerve head pathology in 223 (40.3%) eyes. The iris malformation type was significantly positively correlated with AAK stage, lens properties, presence of glaucoma, congenital macular, and optic nerve head properties (p < 0.001 for all), while complete aniridia showed the most complications. CONCLUSIONS: At the Homburg Aniridia Center, the most common ophthalmic signs in congenital aniridia were AAK, iris malformation, cataract, and macular hypoplasia. The iris malformation type may indicate future expression of AAK, cataract, and glaucoma development and it is correlated with a congenital optic nerve head and macular pathology. Our registry will support further detailed longitudinal analysis of ophthalmic and systemic diseases of aniridia subjects during long-term follow-up.

Epidemiology of PAX6 Gene Pathogenic Variants and Expected Prevalence of PAX6-Associated Congenital Aniridia across the Russian Federation: A Nationwide Study.

This study investigates the distribution of PAX6-associated congenital aniridia (AN) and WAGR syndrome across Russian Federation (RF) districts while characterizing PAX6 gene variants. We contribute novel PAX6 pathogenic variants and 11p13 chromosome region rearrangements to international databases based on a cohort of 379 AN patients (295 families, 295 probands) in Russia. We detail 100 newly characterized families (129 patients) recruited from clinical practice and specialized screening studies. Our methodology involves multiplex ligase-dependent probe amplification (MLPA) analysis of the 11p13 chromosome, PAX6 gene Sanger sequencing, and karyotype analysis. We report novel findings on PAX6 gene variations, including 67 intragenic PAX6 variants and 33 chromosome deletions in the 100 newly characterized families. Our expanded sample of 295 AN families with 379 patients reveals a consistent global PAX6 variant spectrum, including CNVs (copy number variants) of the 11p13 chromosome (31%), complex rearrangements (1.4%), nonsense (25%), frameshift (18%), and splicing variants (15%). No genetic cause of AN is defined in 10 patients. The distribution of patients across the Russian Federation varies, likely due to sample completeness. This study offers the first AN epidemiological data for the RF, providing a comprehensive PAX6 variants spectrum. Based on earlier assessment of AN prevalence in the RF (1:98,943) we have revealed unexamined patients ranging from 55% to 87%, that emphases the need for increased awareness and comprehensive diagnostics in AN patient care in Russia.

Pediatric glaucoma in aniridia in a population of Egyptian children.

PURPOSE: To report on the incidence, characteristics, and treatment of glaucoma in association with aniridia in a population of Egyptian children. METHODS: A retrospective chart review was conducted of children (<18 years of age) presenting with aniridia between 2007 and 2022. Diagnosis of glaucoma was based on cup:disk ratio (>0.3) and IOP (>16 mm Hg). Success of glaucoma surgery was defined as IOP ≤16 mm Hg and stable or regressing cup:disk ratio. RESULTS: A total of 93 eyes of 47 children were included. The mean patient age at presentation was 41.2 ± 44.7 months. The mean intraocular pressure (IOP), corneal diameter, cup:disk ratio, and axial length on presentation were 16.4 ± 10.3 mm Hg, 11.4 ± 1.3 mm, 0.4 ± 0.3, and 22.43 ± 2.6 mm Hg. Of eyes with IOP and cup:disk ratio data at presentation, 23 (30%) were diagnosed with glaucoma. Fourteen eyes underwent surgery after presentation; follow-up data were available for half the remaining eyes. At the final follow-up, glaucoma was present in 20 eyes (49%). Glaucoma surgery was performed in 17 eyes, with a complete or qualified success rate of 82.4% at final follow-up, with 15 eyes having at least 12 months' follow-up. CONCLUSIONS: In this study cohort, children with aniridia presented at around 3 years of age, with glaucoma at presentation in almost one-third of the cases.

[Congenital aniridia - Hungarian data of a spectrum disease]. / Congenitalis aniridia ­ egy spektrumbetegség magyarországi adatai.

INTRODUCTION: Congenital aniridia is a rare disease, characterised by the complete or partial absence of the iris, but lesions may be present in all structures of the eye. OBJECTIVE: To determine the prevalence of ocular diseases in congenital aniridia by analyzing patients from a Hungarian centre. PATIENTS AND METHODS: Patients at the Department of Ophthalmology of Semmelweis University, examined between October 2005 and May 2022, have been included. After taking the patients' medical history, a detailed ophthalmological examination has been performed. RESULTS: Of the 82 patients in the database, 33 (age 25.69 ± 17.49 [5-59] years, 17 females [51.51%]) presented for examination and 65 eyes were examined. Nystagmus was found in 45 eyes of 23 patients (69.23%), and the patients' uncorrected distance visual acuity was 0.14 ± 0.128 (0.9 logMAR; 0.63-0.005). The aniridia-associated keratopathy was Grade 0 in 8 eyes (12.3%), Grade 1 in 10 eyes (15.38%), Grade 2 in 16 eyes (24.62%), Grade 3 in 4 eyes (6.15%) and Grade 4 in 25 eyes (38.46%). 30 eyes (46.15%) of 15 patients had secondary glaucoma, 6 eyes (9.2%) of 3 patients were glaucoma suspect. 8 eyes (12.3%) had a clear lens, 44 eyes (67.69%) had cataract, of which 22 (33.84%) were anterior cortical polar cataracts. 13 eyes (20%) were pseudophakic (PCL) and 7 eyes (10.77%) had lens dislocation or zonular insufficiency. Macular hypoplasia was found in 6 eyes of 3 patients (4.6%) and optic nerve head malformation in 2 eyes of 1 patient (3.03%). CONCLUSION: The ocular signs of congenital aniridia are aniridia-associated keratopathy, secondary glaucoma, cataract, macular and optic nerve head hypoplasia. Systematic collaboration of different ophthalmological specialties is required for the management and care of all these ocular abnormalities. Orv Hetil. 2023; 164(4): 148-155.

[National protocol for diagnosis and care of congenital aniridia: Summary for the attending physician]. / Protocole national de diagnostic et de soins (PNDS) de l'aniridie congénitale : synthèse pour le médecin traitant.

Congenital aniridia is a rare panocular disease defined by a national diagnostic and care protocol (PNDS) validated by the HAS. In most cases, it is due to an abnormality in the PAX6 gene, located at 11p13. Aniridia is a potentially blinding autosomal dominant disease with high penetrance. The prevalence varies from 1/40,000 births to 1/96,000 births. Approximately one third of cases are sporadic. Ocular involvement includes complete or partial absence of iris tissue, corneal opacification with neovascularization, glaucoma, cataract, foveal hypoplasia, optic disc hypoplasia and ptosis. These ocular disorders coexist to varying degrees and progress with age. Congenital aniridia manifests in the first months of life as nystagmus, visual impairment and photophobia. A syndromic form such as WAGR syndrome, WAGRO syndrome (due to the risk of renal Wilms tumor) or Gillespie syndrome (cerebellar ataxia) must be ruled out. Systemic associations may include diabetes, due to expression of the PAX6 gene in the pancreas, as well as other extraocular manifestations. Initial assessment is best carried out in a referral center specialized in rare ophthalmologic diseases, with annual follow-up. The management of progressive ocular involvement must be both proactive and responsive, with medical and surgical management. Visual impairment and photophobia result in disability, leading to difficulties in mobility, movement, communication, learning, fine motor skills, and autonomy, with consequences in personal, school, professional, socio-cultural and athletic life. Medico-socio-educational care involves a multidisciplinary team. Disability rehabilitation must be implemented to prevent and limit situations of handicap in activities of daily living, relying on the Commission for the Rights and Autonomy of People with Disabilities (CDAPH) within the Departmental House of People with Disabilities (MDPH). The general practitioner coordinates multidisciplinary medical and paramedical care.

Analysis of genotype-phenotype correlations in PAX6-associated aniridia.

BackgroundAniridia is a severe autosomal dominant panocular disorder associated with pathogenic sequence variants of the PAX6 gene or 11p13 chromosomal aberrations encompassing the coding and/or regulatory regions of the PAX6 gene in a heterozygous state. Patients with aniridia display several ocular anomalies including foveal hypoplasia, cataract, keratopathy, and glaucoma, which can vary in severity and combination.MethodsA cohort of 155 patients from 125 unrelated families with identified point PAX6 pathogenic variants (118 patients) or large chromosomal 11p13 deletions (37 patients) was analyzed. Genetic causes were divided into 6 types. The occurrence of 6 aniridic eye anomalies was analyzed. Fisher's exact test was applied for 2×2 contingency tables assigning numbers of patients with/without each sign and each type of the PAX6 variants or 11p13 deletions with Benjamini-Hochberg correction. The age of patients with different types of mutation did not differ.ResultsPatients with 3'-cis-regulatory region deletions had a milder aniridia phenotype without keratopathy, nystagmus, or foveal hypoplasia. The phenotypes of the patients with other rearrangements involving 11p13 do not significantly differ from those associated with point pathogenic variants in the PAX6 gene. Missense mutations and genetic variants disrupting splicing are associated with a severe aniridia phenotype and resemble loss-of-function mutations. It is particularly important that in all examined patients, PAX6 mutations were found to be associated with multiple eye malformations. The age of patients with keratopathy, cataract, and glaucoma was significantly higher than the age of patients without these signs.ConclusionWe got clear statistically significant genotype-phenotype correlations in congenital aniridia and evident that aniridia severity indeed had worsened with age.

Clinical, molecular genetics and therapeutic aspects of syndromic obesity.

Obesity has become a major health problem worldwide. To date, more than 25 different syndromic forms of obesity are known in which one (monogenic) or multiple (polygenic) genes are involved. This review gives an overview of these forms and focuses more in detail on 6 syndromes: Prader Willi Syndrome and Prader Willi like phenotype, Bardet Biedl Syndrome, Alström Syndrome, Wilms tumor, Aniridia, Genitourinary malformations and mental Retardation syndrome and 16p11.2 (micro)deletions. Years of research provided plenty of information on the molecular genetics of these disorders and the obesity phenotype leading to a more individualized treatment of the symptoms, however, many questions still remain unanswered. As these obesity syndromes have different signs and symptoms in common, it makes it difficult to accurately diagnose patients which may result in inappropriate treatment of the disease. Therefore, the big challenge for clinicians and scientists is to more clearly differentiate all syndromic forms of obesity to provide conclusive genetic explanations and eventually deliver accurate genetic counseling and treatment. In addition, further delineation of the (functions of the) underlying genes with the use of array- or next-generation sequencing-based technology will be helpful to unravel the mechanisms of energy metabolism in the general population.

Prevalence, Incidence, and Risk Factors for the Development of Glaucoma in Patients With Aniridia.

PURPOSE: To assess the prevalence, incidence, and risk factors for the development of glaucoma in patients with aniridia. METHODS: Retrospective analysis of case records of patients diagnosed as having congenital aniridia between January 1986 and December 2011 was performed. Patients with a follow-up of more than 12 months were included. RESULTS: Ninety-one patients (180 eyes) with the diagnosis of aniridia were identified from the case records. Two eyes were excluded from the final analysis; one had developed phthisis and the other had been enucleated. Seventy-four patients (81.3%) were younger than 18 years at initial presentation. The prevalence of glaucoma at presentation was 28.8%, which could be further categorized as ocular hypertension in 19 eyes (10.5%) and glaucoma in 33 eyes (18.3%). Thirty-one eyes (28.4%) developed elevated intraocular pressure (IOP) during the follow-up period: ocular hypertension in 23 eyes (17.9%) and glaucoma in 8 eyes (6.25%). The mean IOP at the time of diagnosis was 33.9 ± 8.6 mm Hg (range: 24 to 60 mm Hg). The mean duration of follow-up was 8.1 ± 5.7 years (range: 1 to 28 years). The cumulative probability of developing elevated IOP was 4% at the end of 8 years of follow-up; this increased to 88% at the end of 28 years of follow-up. Univariate logistic regression analysis identified higher baseline IOP (odds ratio [OR]: 1.2; 95% confidence interval [CI]: 1.2 to 1.4) and limbal stem cell deficiency (OR: 2.8; 95% CI: 1.4 to 5.6) as significant risk factors for the development of elevated IOP. Higher baseline IOP remained significant on multivariate analysis (OR: 1.2; 95% CI: 1.2 to 1.4). CONCLUSIONS: Glaucoma occurs in a substantial proportion of patients with aniridia. Eyes with increased IOP at baseline are at a higher risk. [J Pediatr Ophthalmol Strabismus. 2017;54(4):250-255.].

PAX6 allelic heterogeneity in Mexican congenital aniridia patients: expanding the mutational spectrum with seven novel pathogenic variants.

IMPORTANCE: The importance of the study was to describe the clinical characteristics and mutational analysis of Mexican patients with aniridia. BACKGROUND: Aniridia is a panocular hereditary eye disease caused by mutations in the PAX6 transcription factor. Mutation detection rate is highly variable ranging from 30% to 90% in different populations. Very few studies have been published about the PAX6 mutational analysis in aniridia patients from Mexico. In order to establish a more representative PAX6 mutational frequency in the country, a cohort of 22 Mexican unrelated aniridia probands were analysed in this study. DESIGN: Case series. PARTICIPANTS: A total of 22 Mexican probands with bilateral isolated aniridia and their available relatives were included. METHODS: Sanger sequencing was used for the mutational analysis of all coding exons and flanking intronic regions of PAX6. MAIN OUTCOME MEASURES: Clinical characteristics and results of PAX6 mutational analysis in probands with aniridia and available family members. RESULTS: Molecular analysis of PAX6 in 22 index cases with aniridia allowed the identification of a total of 16 different mutations. Seven of these pathogenic variants are novel, including c.183C>G, p.(Y61*); c.718delC, p.(R240Efs*3); c.1149_1152delTCAG, p.(P385Wfs*139); c.257_266delAAATAGCCCA, p.(K86Sfs*35); c.836_843dupGCAACACA p.(P282Afs*86); c.1032+2_1032+3insT; and c.141+2T>A. Inter and intrafamilial phenotypic heterogeneity was found. CONCLUSIONS AND RELEVANCE: The mutational diagnostic rate in this series was 77%, which is comparable with reports from other populations. Importantly, no founder mutations were identified in this case series. Our results add 7 novel PAX6 pathogenic variants to the aniridia-related mutational spectrum and reveal considerable PAX6 allelic heterogeneity in this population.

Novel variants in PAX6 gene caused congenital aniridia in two Chinese families.

PurposeTo reveal the underlying genetic defect in two four-generation Chinese families with aniridia and explore the pathologic mechanism.MethodsFull ophthalmic examinations were performed in two families with aniridia. The PAX6 gene was directly sequenced in patients of two families, and the detected variants were screened in unaffected family members and two hundred unrelated healthy controls. Real-time quantitative PCR was used to explore pathologic mechanisms of the two variants.ResultsAniridia, cataract, and oscillatory nystagmus were observed in patients of the two families. In addition, we observed corneal opacity and microphthalmus in family 1, and strabismus, left ectopia lentis, microphthalmus, and microcornea in family 2. Sanger sequencing detected a novel 1-bp duplication (c.50dupA) in family 1 and a novel 2-bp splice site deletion (c.765+1_765+2delGT) in family 2. Sequencing of cDNA indicated skipping of exon 9 caused by the splice site deletion, being predicted to cause a premature stop codon, as well as the duplication. The PAX6 mRNA significantly lower in patients with aniridia than in unaffected family members in both families, suggesting that the duplication and splice site deletion caused nonsense-mediated mRNA decay.ConclusionsOur study identified two novel PAX6 variants in two families with aniridia and revealed the pathogenicity of the variants; this would expand the variant spectrum of PAX6 and help us better understand the molecular basis of aniridia, thus facilitating genetic counseling.

A clinical study of Aicardi syndrome in Northern Ireland: the spectrum of ophthalmic findings.

PurposeAicardi syndrome is a rare disorder, affecting ~1 in 100 000 live births. Chorioretinal lacunae feature alongside agenesis of the corpus callosum and spasms in flexion to make up a diagnostic triad. Recently ophthalmic findings such as microphthalmia and optic disc anomalies have been recognised in association with Aicardi syndrome. This population study aims to determine the presence of ocular findings and identifies some novel associations in these patients.MethodsA retrospective review of charts for seven patients with Aicardi syndrome was carried out.ResultsThe incidence of Aicardi syndrome in Northern Ireland was found to be 1 in 110 000 live births. Four patients who had microphthalmus also had iris abnormalities; two patients with bilateral microphthalmus had partial aniridia and two patients with unilateral microphthalmus had iris coloboma in the same eye. Optic disc abnormalities were found in 11 eyes of six patients. Two patients were found to have areas of fibrovascular proliferation with a thickened white ridge and avascular zone beyond. Both of these patients developed retinal detachments.ConclusionsOur review of patients with Aicardi syndrome in Northern Ireland has revealed some novel clinical findings, including aniridia in two cases. We also found a higher than previously reported rate of excavated disc anomalies of 50% in our cohort. We found two cases of peripheral retinal dysplasia, which has not been previously reported. This finding was associated with microphthalmus and severe optic disc abnormalities, and we feel this warrants early EUA to enable early treatment and hopefully result in better visual prognosis.

Aniridia: a comparative overview.

BACKGROUND AND PURPOSE: Aniridia is linked to a mutation of the PAX6 gene, which results in panocular anomalies. A set of common secondary pathologies associated with aniridia is recognized. Much of the literature on aniridia focuses on genetic factors of the disorder and associated abnormalities, both ocular and nonocular. The field of research on the prevalence of pathology secondary to ocular abnormalities associated with aniridia is limited, with many of the studies based on low patient numbers. This study contributes patient data on the prevalence and significance of ocular pathology in aniridia. PATIENTS AND METHOD: We conducted a retrospective chart review of patients with aniridia treated at the Vanderbilt Eye Institute between July 1, 2011, and July 1, 2012. We compiled data on visual acuities and ocular pathologies, comparing our results with previous studies. RESULTS: The percentage of patients in our study with nystagmus and cataract was within the range reported among several studies. However, the rate of glaucoma and corneal disease among our adult study patients was higher. Despite being a prominent feature of aniridia, retinal pathology is difficult to quantify; data on retinal pathology is scarce in the literature and difficult to obtain through a retrospective chart review due to the multiple factors impacting the retina in aniridia. CONCLUSION: In addition to the challenges posed by ocular anomalies that occur in anirida, the progressive nature of processes common in the condition have significant implications for long-term visual outcomes.

Glaucoma and frequency of ocular and general diseases in 30 patients with aniridia: a clinical study.

PURPOSE: To evaluate the following in patients with aniridia: age at first examination at the University Eye Hospital and age at diagnosis of glaucoma; visual acuity; frequency of family history of aniridia; and frequency of ocular and general diseases associated with aniridia. METHODS: This was a consecutive examination of 30 unrelated patients with aniridia and retrospective evaluation of ophthalmologic, pediatric, and internal findings. The relative frequency of age at glaucoma diagnosis within decades was evaluated for the 20 patients with aniridia and glaucoma. Statistical analysis was performed using the Mann-Whitney test. RESULTS: Relative frequency of the age of patients with aniridia at time of glaucoma diagnosis within the following decades was as follows: from birth to 9 years: 15%, 10-19: 15%, 20-29: 15%, 30-39: 15%, 40-49: 35%, and 50-59: 5%. Visual acuity in the better eye of 20/100 or less was found in 60%. Family history of aniridia was found in 33.3% of patients, with 1-4 relatives with aniridia. A total of 76.7% of patients had congenital cataract, and 66.7% had glaucoma. Mean maximum intraocular pressure of the 20 patients with glaucoma was 35.9 mmHg in the right and 32.6 mmHg in the left eye. A total of 53.3% had nystagmus, 26.6% corneal opacifications, 16.7% bilateral lens dislocation upwards, 6.7% optic nerve hypoplasia, 3.3% poor foveal development, and 3.3% Wilms tumor. CONCLUSIONS: Up to the age of 40 years, 15% of patients were diagnosed with glaucoma per age decade. Frequent bilateral glaucoma and similar bilateral height of intraocular pressure suggest a genetic glaucoma disposition with malformation at Schlemm canal, besides possible sequential anatomic changes in the chamber angle. Associated ocular abnormalities limit visual prognosis.

Clinical features of Korean patients with congenital aniridia.

PURPOSE: To investigate the clinical features of Korean patients with congenital aniridia. METHODS: This retrospective study focused on 60 eyes from 31 patients who were diagnosed with congenital aniridia at Kangnam St. Mary's Hospital from 1996 to 2007. Patient age, gender, visual acuity (VA), family history, and previous ocular history were recorded. The presence of keratopathy, glaucoma, cataract, foveal hypoplasia, and other ocular or systemic anomalies were evaluated for each patient. RESULTS: The proportion of sporadic cases was 29.0%. Cataract (82.5%), glaucoma (51.6%), keratopathy (71.6%), and foveal hypoplasia (81.8%) commonly accompanied aniridia. Thirty-four (60.7%) eyes had VAs less than 20/200 and 20 eyes (35.7%) had VAs between 20/200 and 20/60. In patients without a past history of ocular surgery, the mean central corneal thickness was 643.05 ± 37.67 µm and the mean endothelial cell count was 3,349.44 ± 408.17 cells/mm(2). Ocular surface surgeries were performed in 6 eyes. The clarity of the transplanted corneal graft vanished in 5 eyes with the progression of peripheral neovascularization and subepithelial fibrosis. The mean age of cataract surgery in 8 eyes was 29.8 ± 5.9 years. Postoperative worsening of corneal clouding and glaucomatous damage were observed in 4 eyes. Two infants had bilateral congenital glaucoma. Two children with sporadic aniridia were identified to have Wilm's tumors. CONCLUSIONS: Congenital aniridia is a progressive congenital disorder that is commonly accompanied by complications that can lead to impaired vision. Regular, careful examinations for these accompanying complications should be performed in all patients with congenital aniridia.

Corneal involvement in congenital aniridia.

PURPOSE: The purpose of this research is 2-fold. First of all, the level of keratopathy development in patients with congenital aniridia is studied. In addition, a correlation between the effects of ocular surgery on the severity of keratopathy is made. METHODS: A thorough search for the total number of patients with aniridia in Sweden and Norway was performed. One hundred eighty-one patients were identified and 124 (69%) of these were examined. Three artificial eyes, 16 eyes with corneal transplants, and 1 eye with a corneal limbal allograft were excluded from the study. All participating patients underwent clinical ophthalmologic examinations, including photographs, and their medical history was recorded. A slit lamp was used to examine the presence of keratopathy. RESULTS: Visible keratopathy was found in 80% of the eyes. Keratopathy that caused impaired visual acuity was found in 26% of the eyes. The study displayed a significant correlation between the level of keratopathy and the patient's age. A significant correlation between the level of keratopathy and intraocular surgery exists. This is irrespective of the patient's age. The study also found that irrespective of the patient's age, a significant correlation between the level of keratopathy and impaired corneal sensitivity exists. CONCLUSIONS: This research identified the presence of visible keratopathy in 80% of eyes. In addition, 26% of eyes had a keratopathy level that caused visual disturbances. The study showed that the prevalence and severity of keratopathy increased with the patient's age. Further conclusions are that intraocular surgery increases the severity of keratopathy and that the severity of keratopathy is correlated to reduced corneal sensitivity. Finally, extreme care should be taken when selecting patients for intraocular surgery because this procedure can trigger the development of keratopathy.

Genotype/phenotype association in Indian congenital aniridia.

The developmental birth eye disorder of iris is known as aniridia. Heterozygous PAX6 gene, which causes human aniridia and small eye in mice, is located on chromosome 11p13. The variability had been documented between the affected individuals within the families, is due to genotypic variation. Haploinsufficiency renders PAX6 allele non-functional or amorphic, however it presents hypomorphic or neomorphic alleles. India is not a well-studied ethnic group, hence the focus on congenital aniridia gene analysis supports the literature and the phenotypic association were analysed both in sporadic as well as familial. The consistent association of truncating PAX6 mutations with the phenotype is owing to non-sense-mediated decay (NMD). It is presumed that the genetic impact of increased homozygosity and heterozygocity in Indian counter part arises as the consequence of consanguineous marriages. The real fact involved in congenital aniridia with other related phenotypes with PAX6 mutations are still controversial.

Aniridia among children and teenagers in Sweden and Norway.

PURPOSE: To investigate patients under the age of 20 with aniridia in Sweden and Norway in order to estimate the prevalence of aniridia, to describe clinical signs and identify complications in the young, which will help improve diagnostic tools and treatment. METHODS: A thorough search for patients with aniridia (of all ages) was performed. Sixty-two of the 181 patients were under the age of 20. Fifty-two of them were examined and they constituted the study population. Patient history was obtained and all participants underwent clinical ophthalmologic examination, including photography. Blood samples were taken for mutation analysis. RESULTS: Epidemiological data are only based on the results in Sweden. The age-specific prevalence in Sweden was 1:47,000, male/female ratio was 0.57, mean age 12 years and median age 14 years. The proportion of sporadic cases including WAGR (Wilms tumour, Aniridia, Genitourinary abnormalities, Mental Retardation) and Gillespie syndrome (aniridia, cerebellar ataxia and mental retardation) was 48%. In the entire study population (Sweden and Norway), the mean visual acuity (VA) was 0.2 (range 0.04-0.9). We found VA < 0.3 in 80% and <0.1 in 18% of the patients. Twenty-two patients (42%) had one or more of the sight threatening complications such as cataract/lens luxation, corneal clouding or glaucoma. CONCLUSION: Descriptions of aniridia in the younger are rare. This study shows that aniridia seems to be more common than previously estimated and that some complications appear early in life. Watchfulness as regards these complications and regular examinations are essential even in the youngest.

Epidemiology of aniridia in Sweden and Norway.

PURPOSE: To investigate the epidemiology of aniridia in the populations of Sweden and Norway. METHODS: A thorough search for aniridia patients has been performed in Sweden and Norway. All participants had a clinical ophthalmological examination documented through photography. Blood samples were taken for mutation analysis and pedigrees were established. RESULTS: A total of 181 patients with aniridia were identified in the two countries. This gives an age-specific prevalence of 1:72,000 in the entire region, 1:70,000 in Sweden and 1:76,000 in Norway. A total of 124 individuals (69%) were examined. Male/female ratio was 0.94 (Sweden 0.85 and Norway 1.2). Mean age of the examined patients was 29 years and median age 25 years. We did not find any significant age difference between the two countries. The mean visual acuity (VA) was 0.19 (Sweden 0.19 and Norway 0.18).The number of families with more than one affected member was 31 and the number of sporadic cases was 40. CONCLUSION: We have done a thorough search of the literature, but we have found no earlier studies describing aniridia in an entire country and only a few reports from larger areas. We assume that most aniridia patients have been found and the aniridia prevalence of 1:72,000 can be regarded as well supported. Further studies on other aspects of aniridia are in progress, and information from these can contribute to guidelines for the care of patients with this rare but serious disease.

Congenital eye and adnexial anomalies in Kano, a five year review.

BACKGROUND: Knowledge of prevalence and types of congenital eye and adnexial anomalies is important as some of these anomalies can lead to childhood blindness. The aim of the study is to determine the types of congenital eye and adnexial anomalies seen in the eye clinic of Aminu Kano Teaching Hospital Kano, Nigeria between the years 2001 to 2005. To determine the proportion of children below the age of 10 years who presented with congenital eye and adnexial anomalies, the proportion of eye surgeries due to such anomalies, and proportion of these anomalies amenable to (surgical) intervention. METHODS: The clinic and theater registers were used to obtain the total number of children less than 10 years of age seen and those that had surgery during the review period. A list of those with congenital eye and adnexial anomalies was compiled. The case folders of patients with such anomalies were retrieved and information on age, sex, type of anomaly, laterality of the condition, and types of surgical intervention offered, was obtained. The data was manually analyzed. RESULTS: There were 4163 children seen in the eye clinic and 268 had surgery during the review period. There were 109 eyes of 69 patients with congenital eye and adnexial anomalies. The prevalence of such anomalies amongst children (<10 years of age) is 1.7% and surgery for congenital eye and adnexial anomalies accounted for 25.7% of eye surgeries in the study population. The male to female ratio is 2.3:1. In 40 patients, the anomaly was bilateral and it was unilateral in 29 patients. The commonest congenital anomalies are buphthalmos in 38%, cataracts in 35%, and naso lachrymal duct obstruction in 14%. Other less frequent anomalies are anophthalmia/micophthalmia, limbal dermoid cysts and aniridia. Eighty six percent of the patients had surgery to correct the anomaly. CONCLUSION: Most of the congenital anomalies seen in our hospital can lead to childhood blindness and vigilance by eye care providers is advised to ensure prompt identification and intervention.