M. Ashwin Reddy

Alpha-B crystallin gene (CRYAB) mutation causes dominant congenital posterior polar cataract in humans.

Congenital cataracts are an important cause of bilateral visual impairment in infants. In a four-generation family of English descent, we mapped dominant congenital posterior polar cataract to chromosome 11q22-q22.3. The maximum LOD score, 3.92 at recombination fraction 0, was obtained for marker D11S898, near the gene that encodes crystallin alpha-B protein (CRYAB). By sequencing the coding regions of CRYAB, we found in exon 3 a deletion mutation, 450delA, that is associated with cataract in this family. The mutation resulted in a frameshift in codon 150 and produced an aberrant protein consisting of 184 residues. This is the first report of a mutation, in this gene, resulting in isolated congenital cataract.

A Genotype-Phenotype Comparison of ADAMTSL4 and FBN1 in Isolated Ectopia Lentis

PURPOSE To describe the genotype-phenotype relationship of a cohort of consecutive patients with isolated ectopia lentis (EL) secondary to ADAMTSL4 and FBN1 mutations. METHODS Patients underwent detailed ocular, cardiovascular, and skeletal examination. This was correlated with Sanger sequencing of ADAMTSL4 and FBN1 genes. RESULTS Seventeen patients were examined, including one with ectopia lentis et pupillae. Echocardiography and skeletal examination revealed no sign of systemic disorders associated with EL, in particular Marfan syndrome (MFS). Nine patients (52.9%) were found to have mutations in ADAMTSL4, including four novel nonsense mutations. Four patients (25%) were found to have novel FBN1 mutations, not previously reported as causing classical Marfan syndrome. One additional patient was found to have an FBN1 mutation previously reported in classical MFS. Four patients (25%) were found to have no mutations in either gene. Median age of diagnosis of EL was 35 years in patients with FBN1 mutations and 2 years in patients with ADAMTSL4 mutations (P < 0.01). Mean axial length was 22.74 mm (95% confidence interval [CI]: 21.3-24.2) (FBN1) and 27.54 mm (95% CI: 24.2-30.9) (ADAMTSL4) (P < 0.01). Other ophthalmic features, including corneal thickness and power, foveal thickness, visual acuity, and direction of lens displacement, were similar for both groups. CONCLUSIONS ADAMTSL4 is the most important known causative gene in isolated EL. Mutations in ADAMTSL4 appear to cause earlier manifestation of EL and are associated with increased axial length as compared to FBN1. We suggest that ADAMTSL4 be screened in all patients with isolated EL and that physicians be vigilant for the more severe ocular phenotype associated with mutations in this gene.

Relationships between Maternal Ethnicity, Gestational Age, Birth Weight, Weight Gain, and Severe Retinopathy of Prematurity

OBJECTIVE To develop an algorithm that allows advanced identification of infants requiring treatment for retinopathy of prematurity (ROP). STUDY DESIGN A retrospective observational study was performed at 2 tertiary neonatal units serving a multiethnic population in the UK, using data on 929 infants eligible for ROP screening. The relationships between study variables and the risk of developing ROP requiring treatment were analyzed using multiple logistic regression. RESULTS After applying exclusion criteria, data from 589 infants were analyzed; of these, 57 required laser treatment. The proportion of treated infants was 5.9% of those born to black mothers, 9.39% of those born to white mothers, and 12.8% of those born to Asian mothers (P = .047). Multiple logistic regression showed that gestational age, birth weight, maternal ethnicity, and early weight gain were predictors for the development of ROP requiring treatment, with maternal ethnicity having greater predictive power compared with early weight gain. We developed an algorithm for predicting the development of ROP requiring treatment with sensitivity, specificity, and positive and negative predictive values of 100%, 65.7%, 23.8%, and 100%, respectively. CONCLUSION Gestational age, birth weight, early weight gain, and maternal ethnicity are important predictors for the development of ROP requiring treatment. In a multiethnic population, an algorithm to predict development of ROP requiring treatment should include maternal ethnicity. If confirmed through prospective studies, this algorithm could reduce the number of opthalmologic examinations performed for ROP screening.

Visual outcomes following intraophthalmic artery melphalan for patients with refractory retinoblastoma and age appropriate vision

Background/aims To determine the frequency and cause of visual loss following intra-arterial melphalan (IAM) in patients with retinoblastoma with age appropriate vision. Methods Assessment of patients with refractory retinoblastoma that had undergone systemic chemotherapy, with or without local treatment, and were subsequently treated with IAM. Eyes of patients with a healthy foveola were assessed. The main outcome measures included visual, macular (including Pattern Visual Evoked Potentials and Fundus Fluorescein Angiography) and retinal functions (Electroretinograms). Results Five of twelve eyes (42%) demonstrated severe visual loss following IAM at last follow-up (median 21 months). This was due to either retinal detachment (1 eye, 20%) or choroidal ischaemia involving the foveola (4 eyes, 80%). All 3 eyes that had technical difficulties or vasospasm during catheterisation suffered visual loss. 8 out of 10 eyes that had a non-age adjusted dose of melphalan suffered visual loss. Electroretinograms post-IAM deteriorated in 4 of 8 eyes (50%) and Pattern Visual Evoked Potentials deteriorated in 3 (37%), though only one of these 3 showed concomitant visual acuity loss. Conclusions Structural and vascular damage to the foveola limited visual acuity. Complications associated with catheterisation and high doses of melphalan may be contributory factors to visual morbidity. Although visual loss is described, no patient developed metastases and most retained good vision.

The Association of an Epibulbar Dermoid and Duane Syndrome in a Patient with a SALL1 Mutation (Townes-Brocks Syndrome)

Introduction: Townes-Brocks Syndrome (TBS) is an autosomal dominant condition characterized by renal, anal, ear and thumb anomalies caused by SALL1 mutations. Ocular manifestations reported have included congenital cataracts, unilateral microphthalmia, optic nerve atrophy, and unilateral visual loss with bilateral Brushfield Spots. Iris and chorioretinal colobomata were described in one individual whose daughter had Duane syndrome. Methods: We present a case of TBS with a proven SALL1 mutation associated with unique ophthalmic features. Case Report: The first child of healthy unrelated parents was born after an uncomplicated pregnancy with multiple features consistent with TBS. The patient was heterozygous for a pathogenic SALL1 gene mutation c826C > T (pR276X). The child had an epibulbar dermoid and left Type 1 Duane syndrome. He also had tearing when he ate food (crocodile tears). Discussion: This case adds to the current knowledge of ophthalmic associations with SALL1 mutations; features characteristic of SALL1 mutations and others more commonly associated with SALL4 mutations (2) (epibulbar dermoid and Duane) being present. Truncated SALL1 protein alters the localization of full length SALL4 providing a theoretical mechanism for these associations, alternatively SALL1 mutations cause associated eye problems more directly. The possibility of chance association cannot be excluded. Our case is only the second we have found with a SALL1 mutation and TBS with Duane syndrome and the first to also have an epibulbar dermoid. The mutation present is that most commonly associated with TBS. Conclusion: This case increases the demand to examine all children TBS for ophthalmic abnormalities.

Anterior Segment Seeding in Eyes With Retinoblastoma Failing to Respond to Intraophthalmic Artery Chemotherapy

IMPORTANCE Anterior chamber seeding following intraophthalmic artery chemotherapy is rarely reported. OBJECTIVES To describe clinicopathologic observations in eyes in which intraophthalmic artery chemotherapy for retinoblastoma failed and to report anterior chamber involvement. OBSERVATIONS A retrospective case series of 12 enucleated eyes (11 patients) with retinoblastoma refractory to intraophthalmic artery chemotherapy between March 1, 2010, and October 31, 2013, at University College London Institute of Ophthalmology and the Retinoblastoma Service, Royal London Hospital. Data analysis was conducted from June 1, 2014, to March 1, 2015. The International Classification of Retinoblastoma groups were B in 1 eye (8%), C in 4 eyes (33%), and D in 7 eyes (58%). Systemic chemotherapy with vincristine sulfate, etoposide, and carboplatin had failed in 10 patients (91%) and 6 eyes (50%) received additional local treatments. In 6 eyes (50%) anterior chamber invasion was clinically detectable. On histopathologic examination, 4 eyes (33%) had no viable retinal tumor; the remainder had poorly differentiated tumor (6 eyes [50%]) or moderately differentiated tumor (2 eyes [17%]). Anterior segment involvement occurred in the ciliary body and/or ciliary muscle (7 eyes [58%]), iris (6 eyes [50%]), and cornea (4 eyes [33%]). CONCLUSIONS AND RELEVANCE Intraophthalmic artery chemotherapy can fail in eyes with retinoblastoma. In contrast to previous reports on outcomes following intraophthalmic artery chemotherapy, our series shows involvement of the anterior segment of the eye, including the ciliary body, iris, and cornea. Careful case selection and follow-up are advised.

Reduced utility of serum IGF-1 levels in predicting retinopathy of prematurity reflects maternal ethnicity

Aims To validate known risk factors and identify a threshold level for serum insulin-like growth factor 1 (IGF-1) in the development of severe retinopathy of prematurity (ROP) in an ethnically diverse population at a tertiary neonatal unit, 2011–2013. Methods A prospective cohort masked study was conducted. Serum IGF-1 levels at 31, 32 and 33 weeks were measured and risk factor data collected including gestational age (GA), birth weight (BW), absolute weight gain (AWG) and maternal ethnicity. The eventual ROP outcome was divided into two groups: minimal ROP (Stages 0 and 1) and severe ROP (Stage 2 or worse including Type 1 ROP). Results 36 patients were recruited: 14 had minimal ROP and 22 severe ROP. Significant differences between the groups were found in GA, BW, AWG and IGF-1 at 32 and 33 weeks. There was minimal rise in IGF-1 in Stage 2 patients and/or black patients (p=0.0013) between 32 and 33 weeks but no pragmatic threshold level of IGF-1 that could distinguish between minimal or severe ROP. Conclusions There were significant differences in GA, BW, AWG and IGF-1 at 32 and 33 weeks between those babies with severe ROP and those with minimal ROP. However, there was no threshold level of IGF-1 at a time point between 31 and 33 weeks that can be used to exclude a large proportion of babies from screening. We also found ethnic differences in IGF-1 levels with infants born to black mothers having significantly lower IGF-1 levels at 32 and 33 weeks gestation. The determination of ROP risk using IGF-1 is a race-specific phenomenon.

Childhood-onset Leber hereditary optic neuropathy

Background The onset of Leber hereditary optic neuropathy (LHON) is relatively rare in childhood. This study describes the clinical and molecular genetic features observed in this specific LHON subgroup. Methods Our retrospective study consisted of a UK paediatric LHON cohort of 27 patients and 69 additional cases identified from a systematic review of the literature. Patients were included if visual loss occurred at the age of 12 years or younger with a confirmed pathogenic mitochondrial DNA mutation: m.3460G>A, m.11778G>A or m.14484T>C. Results In the UK paediatric LHON cohort, three patterns of visual loss and progression were observed: (1) classical acute (17/27, 63%); (2) slowly progressive (4/27, 15%); and (3) insidious or subclinical (6/27, 22%). Diagnostic delays of 3–15 years occurred in children with an insidious mode of onset. Spontaneous visual recovery was more common in patients carrying the m.3460G>A and m.14484T>C mutations compared with the m.11778G>A mutation. Based a meta-analysis of 67 patients with available visual acuity data, 26 (39%) patients achieved a final best-corrected visual acuity (BCVA) ≥0.5 Snellen decimal in at least one eye, whereas 13 (19%) patients had a final BCVA <0.05 in their better seeing eye. Conclusions Although childhood-onset LHON carries a relatively better visual prognosis, approximately 1 in 5 patients will remain within the visual acuity criteria for legal blindness in the UK. The clinical presentation can be insidious and LHON should be considered in the differential diagnosis when faced with a child with unexplained subnormal vision and optic disc pallor.

Protocol-guided management of paediatric peri-orbital cellulitis: an audit of multidisciplinary care

Maria TsimpidaDepartment of OphthalmologyRoyal London HospitalLondon E1 1BBUKE-mail:maria.tsimpida@bartsandthelondon.nhs.ukMaterial from this article was presented as aposter at the 34th Annual Meeting of theAmerican Association for PediatricOphthalmology and Strabismus, Washington,USA.Present addresses: Daniel Gore: Queen’sHospital, Rom Valley Way, Romford. PetrosPetrou: Attikon Hospital, Haidari, Athens, Greece.The authors have no financial conflicts of interestto disclose.Accepted for publication: 3 February 2010doi:10.1111/j.1365-2753.2010.01452.x

Ocular oncology: advances in retinoblastoma, uveal melanoma and conjunctival melanoma.

Background Retinoblastoma, uveal and conjunctival melanomas are important malignancies within the remit of ocular oncology. Outlined are the diagnostic features and management principles, as well as advancements in the field and current challenges. Sources of data Original papers, reviews and guidelines. Areas of agreement Most eyes with retinoblastoma (International Intraocular Retinoblastoma Classification (IIRC) Group A-D) are salvaged, whereas advanced cases (Group E) remain a challenge. Despite a high rate of local tumour control in uveal melanoma, metastatic spread commonly occurs. Conjunctival melanoma is treated by complete resection, but high rates of local recurrence occur, with the possibility of systemic relapse and death. Areas of controversy Use of the IIRC in retinoblastoma, and systemic screening in melanomas. Growing points Utilization of novel treatment modalities in retinoblastoma and an increasing understanding of the genetic basis of melanomas. Areas timely for developing research Improvements in chemotherapy delivery in retinoblastoma and prognostic tests in melanomas.