Sporadic and Familial Congenital Cataracts: Mutational Spectrum and New Diagnoses Using Next-Generation Sequencing.

Congenital cataracts are a significant cause of lifelong visual loss. They may be isolated or associated with microcornea, microphthalmia, anterior segment dysgenesis (ASD) and glaucoma, and there can be syndromic associations. Genetic diagnosis is challenging due to marked genetic heterogeneity. In this study, next-generation sequencing (NGS) of 32 cataract-associated genes was undertaken in 46 apparently nonsyndromic congenital cataract probands, around half sporadic and half familial cases. We identified pathogenic variants in 70% of cases, and over 68% of these were novel. In almost two-thirds (20/33) of these cases, this resulted in new information about the diagnosis and/or inheritance pattern. This included identification of: new syndromic diagnoses due to NHS or BCOR mutations; complex ocular phenotypes due to PAX6 mutations; de novo autosomal-dominant or X-linked mutations in sporadic cases; and mutations in two separate cataract genes in one family. Variants were found in the crystallin and gap junction genes, including the first report of severe microphthalmia and sclerocornea associated with a novel GJA8 mutation. Mutations were also found in rarely reported genes including MAF, VIM, MIP, and BFSP1. Targeted NGS in presumed nonsyndromic congenital cataract patients provided significant diagnostic information in both familial and sporadic cases.

Efficacy and Safety of Topical Atorvastatin for the Treatment of Dry Eye Associated with Blepharitis: A Pilot Study.

AIMS: To elucidate if topically applied atorvastatin safely decreases corneal fluorescein staining in dry eyes associated with blepharitis. METHODS: Ten dry eye and blepharitis (DEB) patients were enroled in a prospective pilot study. All patients were treated with topical atorvastatin (50 µM) 8 times a day for 4 weeks and allowed to continue with their existing dry eye treatment. The patients were examined weekly for 4 weeks. The primary outcome measure was corneal fluorescein staining. Secondary outcome measures were tear film break-up time (BUT), Schirmer I testing, blepharitis score and bulbar conjunctival injection. The subjective efficacy was evaluated with global symptom and facial analogue scores. RESULTS: An improvement in corneal fluorescein staining in the treated eye by >1 point from baseline to completion of the trial at week 4 was found in 9 of 10 patients (p < 0.01). Topical atorvastatin significantly improved the tear film BUT (p < 0.01), blepharitis score (p < 0.05) and bulbar conjunctival injection (p < 0.05). The global symptom score and facial analogue score also improved (p < 0.05). There were no side effects. CONCLUSION: Topical atorvastatin is a potential therapy for DEB patients. Larger comparative clinical studies are required to establish the efficacy and safety of topical atorvastatin.

Sustained life-like waveform capnography after human cadaveric tracheal intubation.

INTRODUCTION: Fresh frozen cadavers are effective training models for airway management. We hypothesised that residual carbon dioxide (CO2) in cadaveric lung would be detectable using standard clinical monitoring systems, facilitating detection of tracheal tube placement and further enhancing the fidelity of clinical simulation using a cadaveric model. METHODS: The tracheas of two fresh frozen unembalmed cadavers were intubated via direct laryngoscopy. Each tracheal tube was connected to a self-inflating bag and a sidestream CO2 detector. The capnograph display was observed and recorded in high-definition video. The cadavers were hand-ventilated with room air until the capnometer reached zero or the waveform approached baseline. RESULTS: A clear capnographic waveform was produced in both cadavers on the first postintubation expiration, simulating the appearances found in the clinical setting. In cadaver one, a consistent capnographic waveform was produced lasting over 100 s. Maximal end-tidal CO2 was 8.5 kPa (65 mm Hg). In cadaver two, a consistent capnographic waveform was produced lasting over 50 s. Maximal end-tidal CO2 was 5.9 kPa (45 mm Hg). CONCLUSIONS: We believe this to be the first work to describe and quantify detectable end-tidal capnography in human cadavers. We have demonstrated that tracheal intubation of fresh frozen cadavers can be confirmed by life-like waveform capnography. This requires further validation in a larger sample size.

J Donald M Gass MD: father of macular diseases, and one of the ten most influential ophthalmologists of the 20th century.

John Donald MacIntyre Gass, MD was one of the most significant figures to emerge in ophthalmology in the last 100 years. There could be few ophthalmologists who cannot attribute part of their increase in understanding of retinal disease to the influence of Don Gass. His insights opened up opportunities for many new effective therapies. He has influenced ophthalmic thought worldwide, if not by his presence as a visitor, then through his scientific publications, his outstanding books and the international fellows he trained. Like many distinguished physicians, Don Gass's clinical acumen was well grounded in his understanding of ocular pathology. This experience was gained under the mentorship of Lorenz E Zimmerman, MD, who trained a number of distinguished ophthalmologists, who subsequently became professors. Professor Gass passed away on February 26, 2005 at the age of 76 years from pancreatic carcinoma. With the demise of Don Gass, the world of ophthalmology has lost an extraordinary physician of great talent, commonsense and humility. On the other hand it has gained a generation of young ophthalmologists inspired by his example.

Chloramphenicol--not so innocuous: a case of optic neuritis.

The authors present a case of optic neuritis in an adult patient who had been self-prescribing extraordinarily large dosages of chloramphenicol for chronic prostatitis over several years. The visual symptoms resolved upon cessation of the drug and prescription of B group vitamins. Chloramphenicol optic neuritis has not been described in the literature for over 20 years and previously predominantly in children with cystic fibrosis.

Identifying preperimetric functional loss in glaucoma: a blue-on-yellow multifocal visual evoked potentials study.

PURPOSE: To determine the ability of blue-on-yellow multifocal visual evoked potentials (BonY mfVEP) to identify functional loss in preperimetric glaucoma. DESIGN: Prospective case series. PARTICIPANTS: Thirty patients with glaucomatous optic discs and normal standard visual fields. METHODS: All patients underwent BonY mfVEP, dilated optic disc stereophotography, and optical coherence tomography (Fast RNFL protocol). Optic disc photographs were assessed by 2 independent examiners in a masked fashion. MAIN OUTCOME MEASURES: The mfVEP amplitude asymmetry and latency values were analyzed and compared topographically with findings of disc assessment. Average retinal nerve fiber layer (RNFL) thickness, RNFL asymmetry, and sectors with RNFL thinning were compared between patients with and without mfVEP defects. RESULTS: Fourteen (46.7%) patients demonstrated significant abnormality on amplitude asymmetry deviation plots of BonY mfVEP. In all 14 cases, the defect was monocular and corresponded to the eye with the worse disc. In 13 of 14 patients, the defect also corresponded to the location of the worst affected rim. Average RNFL thickness of eyes with mfVEP defects was 81.2+/-9.9 microm, significantly lower than that of patients without defects (90+/-10.5 microm; P = 0.035). Mean asymmetry of RNFL (better minus worse eye) also was significantly higher for patients with mfVEP defects compared with those without such defects (9.0+/-6.4 microm vs. 3.0+/-7 microm; P = 0.03). Average latency of both eyes of glaucomatous patients was delayed compared with that of controls, with no difference in latency between worse and better eyes of glaucoma patients. There was no association of latency delay with either the location of disc changes or mfVEP amplitude defects. CONCLUSIONS: Amplitude asymmetry of the BonY mfVEP seems to be a promising tool to identify functional loss in preperimetric glaucoma. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found after the references.

Novel causative mutations in patients with Nance-Horan syndrome and altered localization of the mutant NHS-A protein isoform.

PURPOSE: Nance-Horan syndrome is typically characterized by severe bilateral congenital cataracts and dental abnormalities. Truncating mutations in the Nance-Horan syndrome (NHS) gene cause this X-linked genetic disorder. NHS encodes two isoforms, NHS-A and NHS-1A. The ocular lens expresses NHS-A, the epithelial and neuronal cell specific isoform. The NHS-A protein localizes in the lens epithelium at the cellular periphery. The data to date suggest a role for this isoform at cell-cell junctions in epithelial cells. This study aimed to identify the causative mutations in new patients diagnosed with Nance-Horan syndrome and to investigate the effect of mutations on subcellular localization of the NHS-A protein. METHODS: All coding exons of NHS were screened for mutations by polymerase chain reaction (PCR) and sequencing. PCR-based mutagenesis was performed to introduce three independent mutations in the NHS-A cDNA. Expression and localization of the mutant proteins was determined in mammalian epithelial cells. RESULTS: Truncating mutations were found in 6 out of 10 unrelated patients from four countries. Each of four patients carried a novel mutation (R248X, P264fs, K1198fs, and I1302fs), and each of the two other patients carried two previously reported mutations (R373X and R879X). No mutation was found in the gene in four patients. Two disease-causing mutations (R134fs and R901X) and an artificial mutation (T1357fs) resulted in premature truncation of the NHS-A protein. All three mutant proteins failed to localize to the cellular periphery in epithelial cells and instead were found in the cytoplasm. CONCLUSIONS: This study brings the total number of mutations identified in NHS to 18. The mislocalization of the mutant NHS-A protein, revealed by mutation analysis, is expected to adversely affect cell-cell junctions in epithelial cells such as the lens epithelium, which may explain cataractogenesis in Nance-Horan syndrome patients. Mutation analysis also shed light on the significance of NHS-A regions for its localization and, hence, its function at epithelial cell junctions.

Paediatric uveal melanoma.

Uveal melanoma is extremely rare in the paediatric population and can be associated with various pre-existing conditions. We report the case of a 9-year-old girl with no predisposing factor who presented with choroidal melanoma. A review of the literature is presented and various clinical, histopathological and prognostic features of paediatric uveal melanoma are discussed.

Chromosomal rearrangements and novel genes in disorders of eye development, cataract and glaucoma.

Disorders of eye development such as microphthalmia and anophthalmia (small and absent eyes respectively), anterior segment dysgenesis where there may be pupillary and iris anomalies, and associated cataract and glaucoma, often lead to visual impairment or blindness. Currently treatment options are limited, as much is unknown about the molecular pathways that control normal eye development and induce the aberrant processes that lead to ocular defects. Mutation detection rates in most of the known genes are generally low, emphasizing the genetic heterogeneity of developmental ocular defects. Identification of the disease genes in these conditions improves the clinical information available for affected individuals and families, and provides new insights into the underlying biological processes for facilitation of better treatment options. Investigation of chromosomal rearrangements associated with an ocular phenotype has been especially powerful for disease gene identification. Molecular characterization of such rearrangements, which pinpoints the region by physically disrupting the causative gene or its regulatory sequences, allows for rapid elucidation of underlying genetic factors that contribute to the phenotype. Genes including PAX6, PITX2, FOXC1, MAF, TMEM114, SOX2, OTX2 and BMP4 have been identified in this way to be associated with developmental eye disorders. More recently, new methods in chromosomal analysis such as comparative genomic hybridization (CGH) microarray, have also enhanced our ability in disease gene identification.

Electrophysiological evidence for heterogeneity of lesions in optic neuritis.

PURPOSE: To examine the natural history of multifocal visual evoked potentials (mfVEPs) within 12 months of the first episode of optic neuritis (ON) in patients with possible multiple sclerosis (MS). METHODS: Twenty-seven patients with a first episode of ON, no previous demyelinating events, and MRI lesions consistent with demyelination were examined with mfVEP. Changes in amplitude and latency of mfVEP were analyzed at 1, 3, 6, and 12 months after an acute attack. RESULTS: Five of 27 patients had persistent loss of amplitude after 12 months of follow-up. This loss was most marked centrally. Amplitude recovered in the remaining 22 patients at 1 month, but delayed latency, which was also most marked centrally, persisted. Of these, two distinct subgroups were identified: six patients with no improvement in latency and 16 patients with significant latency recovery over the 12 months of follow-up, suggesting remyelination. Conversion to MS was highest in the group with severe amplitude loss, followed by the group with no latency recovery. The conversion rate was lowest in the group of patients with latency improvement. CONCLUSIONS: Distinct patterns of disease evolution were identified using mfVEP in patients with first episode of optic neuritis and at high risk for MS, supporting the concept of heterogeneity of early lesions in MS.

Dichoptic stimulation improves detection of glaucoma with multifocal visual evoked potentials.

PURPOSE: To determine whether simultaneous binocular (dichoptic) stimulation for multifocal visual evoked potentials (mfVEP) detects glaucomatous defects and decreases intereye variability. METHODS: Twenty-eight patients with glaucoma and 30 healthy subjects underwent mfVEP on monocular and dichoptic stimulation. Dichoptic stimulation was presented with the use of virtual reality goggles (recording time, 7 minutes). Monocular mfVEPs were recorded sequentially for each eye (recording time, 10 minutes). RESULTS: Comparison of mean relative asymmetry coefficient (RAC; calculated as difference in amplitudes between eyes/sum of amplitudes of both eyes at each segment) on monocular and dichoptic mfVEP revealed significantly lower RAC on dichoptic (0.003 +/- 0.03) compared with monocular testing (-0.02 +/- 0.04; P = 0.002). In all 28 patients, dichoptic mfVEP identified defects with excellent topographic correspondence. Of 56 hemifields (28 eyes), 33 had Humphrey visual field (HFA) scotomas, all of which were detected by dichoptic mfVEP. Among 23 hemifields with normal HFA, two were abnormal on monocular and dichoptic mfVEP. Five hemifields (five patients) normal on HFA and monocular mfVEP were abnormal on dichoptic mfVEP. In all five patients, corresponding rim changes were observed on disc photographs. Mean RAC of glaucomatous eyes was significantly higher on dichoptic (0.283 +/- 0.18) compared with monocular (0.199 +/- 0.12) tests (P = 0.0006). CONCLUSIONS: Dichoptic mfVEP not only detects HFA losses, it may identify early defects in areas unaffected on HFA and monocular mfVEP while reducing testing time by 30%. Asymmetry was tighter among healthy subjects but wider in patients with glaucoma on simultaneous binocular stimulation, which is potentially a new tool in the early detection of glaucoma.

Proteome map of normal rat retina and comparison with the proteome of diabetic rat retina: new insight in the pathogenesis of diabetic retinopathy.

We have employed proteomics to establish a proteome map of the normal rat retina. This baseline map was then used for comparison with the early diabetic rat retinal proteome. Diabetic rat retinae were obtained from Dark Agouti rats after 10 wk of streptozotocin-induced hyperglycaemia. Extracted proteins from normal and diabetic rat retinae were separated and compared using 2-DE. A total of 145 protein spots were identified in the normal rat retina using MALDI-MS and database matching. LC-coupled ESI-MS increased the repertoire of identified proteins by 23 from 145 to 168. Comparison with early diabetic rat retinae revealed 24 proteins unique to the diabetic gels, and 37 proteins absent from diabetic gels. Uniquely expressed proteins identified included the HSPs 70.1A and 8, and platelet activating factor. There were eight spots with increased expression and 27 with decreased expression on diabetic gels. Beta catenin, phosducin and aldehyde reductase were increased in expression in diabetes whilst succinyl coA ligase and dihydropyrimidase-related protein were decreased. Identification of such changes in protein expression has given new insights and a more comprehensive understanding of the pathogenesis of diabetic retinopathy, widening the scope of potential avenues for new therapies for this common cause of blindness.

Euphorbia lactea sap keratouveitis: case report and review of the literature.

PURPOSE: To describe a case of Euphorbia lactea sap keratouveitis and to review all reported cases of ocular toxicity caused by Euphorbia species. METHODS: Case report and review of literature. RESULTS: A 79-year-old woman presented 34 hours after she felt some sap of an E. lactea plant spray into her right eye. Visual acuity was counting fingers at 1 m. Examination revealed ciliary injection, 90% corneal epithelial defect, marked stromal edema with Descemet folds, and anterior-chamber flare with a 1-mm hypopyon. There was no vitreitis, and funduscopy was unremarkable. No foreign body was seen on B scan ultrasound or computed tomography scan of the orbits. Corneal scraping excluded bacterial and herpetic keratitis. Intensive topical antibiotic therapy was started with cephalothin 5% and gentamicin 0.9%, and the pupil was dilated with atropine. Topical steroids were started once the epithelial defect had healed. Examination 11 weeks after the injury revealed minimal subepithelial corneal haze and marked improvement in visual acuity. CONCLUSIONS: To the best of our knowledge, this is only the third reported case of E. lactea sap keratouveitis. The clinical course of E. lactea sap keratouveitis is compared with that reported for other Euphorbia species.

Public education and organ donation: untested assumptions and unexpected consequences.

While the number of individuals able to benefit from transplantation increases with technological developments, donation rates remain insufficient to cater for demand. A universal response to the insufficient number of donor organs has been public education to increase knowledge about donation and transplantation, and to encourage individuals to register their wishes about donation. Although education appears to have increased knowledge and encouraged individuals to register their wishes, it has not increased the number of organs available for transplantation. In fact, there is some evidence that encouraging people to register their wishes may be detrimental to increasing net donation rates. The failure of education programs to increase organ donation rates may be due in part to a failure to recognise that attitudes to donation are influenced by complex socio-cultural and personal beliefs, and not simply by knowledge. Research aiming to increase the rate at which organs are procured for donation must recognise that some individuals do not support transplantation and have their own personal reasons for maintaining this position. Educational interventions should not assume that increasing knowledge or simply encouraging individuals to declare a decision about donation will increase consent to donation.

Deletion at 14q22-23 indicates a contiguous gene syndrome comprising anophthalmia, pituitary hypoplasia, and ear anomalies.

Anophthalmia and pituitary gland hypoplasia are both debilitating conditions where the underlying genetic defect is unknown in the majority of cases. We identified a patient with bilateral anophthalmia and absence of the optic nerves, chiasm and tracts, as well as pituitary gland hypoplasia and ear anomalies with a de novo apparently balanced chromosomal translocation, 46,XY,t(3;14)(q28;q23.2). Translocation breakpoint analysis using FISH and high-resolution microarray comparative genomic hybridization (CGH) has identified a 9.66 Mb deleted region on the long arm of chromosome 14 which includes the genes BMP4, OTX2, RTN1, SIX6, SIX1, and SIX4. Three other patients with interstitial deletions involving 14q22-23 have been described, all with bilateral anophthalmia, pituitary abnormalities, ear anomalies, and a facial phenotype similar to our patient. OTX2 is involved in ocular developmental defects, and the severity of the ocular phenotype in our patient and the other 14q22-23 deletion patients, suggests this genomic region harbors other gene/s involved in ocular development. BMP4 haploinsufficiency is predicted to contribute to the ocular phenotype on the basis of its expression pattern and observed murine mutant phenotypes. In addition, deletion of BMP4 and SIX6 is likely to contribute to the abnormal pituitary development, and SIX1 deletion may contribute to the ear and other craniofacial features. This indicates that contiguous gene deletion may contribute to the phenotypic features in the 14q22-23 deletion patients.

Congenital rubella cataract: a timely reminder in the new millennium?

Maternal infection with rubella in the first trimester is an important cause of congenital cataract. Any injury affecting the foetus following maternal rubella infection in the phase of organogenesis results in congenital defects collectively termed as congenital rubella syndrome (CRS). Although rubella embryopathy is a less common cause for congenital cataract than in the past, it is still seen. The number of cases reduced to one in 1997 after which there were no new cases till 2002. However, there have been two new cases of CRS in 2003. Herein another one in early 2004 is reported. Outbreaks of CRS will continue until the percentage of susceptible individuals is reduced to a minimum through immunization. The majority of rubella cases in Australia are confined to young female immigrants, many coming for marriage. We must continue to immunize children, identify and immunize vaccine failures and susceptible women before they become pregnant, and to screen pregnant women so they can be vaccinated after delivery.

Effect of fixation tasks on multifocal visual evoked potentials.

PURPOSE: This study investigated the effects of cognitive influence on the multifocal visual evoked potential (mVEP) at different levels of eccentricity. Three different foveal fixation conditions were utilized involving varying levels of task complexity. A more complex visual fixation task has been known to suppress peripheral signals in subjective testing. METHODS: Twenty normal subjects had monocular mVEPs recorded using the AccuMap objective perimeter. This allowed simultaneous stimulation of 58 segments of the visual field to an eccentricity of 24 degrees. The mVEP was recorded using three different fixation conditions in random order. During task 1 the subject passively viewed the central fixation area. For task 2 alternating numbers were displayed within the fixation area; the subject on viewing the number '3' in the central fixation area indicated recognition by pressing a button. Throughout task 3, numbers were displayed as in task 2. The subject had the cognitive task of summating all the numbers. RESULTS: Analysis revealed that the increased attention and concentration demanded by tasks 2 and 3 in comparison with task 1 resulted in significantly enhanced central amplitudes of 9.41% (Mann-Whitney P = 0.0002) and 13.45% (P = 0.0002), respectively. These amplitudes became reduced in the periphery and approached those of task 1, resulting in no significant difference between the three tasks. Latencies demonstrated no significant difference between each task nor at any eccentricity (P > 0.05). As the complexity of each task increased the amount of alpha rhythm was significantly reduced. CONCLUSIONS: Our findings indicate that task 1 required a minimal demand of cognition and was associated with the greatest amount of alpha rhythm. It was also the most difficult to perform because of loss of interest. The other two tasks required a greater demand of higher order cognitive skills resulting in significantly enhanced amplitudes centrally and the attenuation of alpha rhythm. Therefore, amplitudes are increased around the area of attention.

Anterior megalophthalmos in a family with 3 female siblings.

This report describes different modes of management in 3 sisters with anterior megalophthalmos. We report our management of the anterior megalophthalmos and a new technique of anterior chamber intraocular lens implantation, which was used in 1 case.