C2orf71 Mutations as a Frequent Cause of Autosomal-Recessive Retinitis Pigmentosa: Clinical Analysis and Presentation of 8 Novel Mutations.

Purpose: To define the phenotype of C2orf71 associated retinopathy and to present novel mutations in this gene. Methods: A retrospective multicenter study of patients with retinopathy and identified C2orf71 mutations was performed. Ocular function (visual acuity, visual fields, electroretinogram [ERG] responses); retinal morphology (fundus, optical coherence tomography); and underlying mutations were analyzed. Results: Thirteen patients from 11 families, who were aged 7 to 63 years (mean: 32.1 years) at their first examination with presumed compound heterozygous (6/13 patients) or homozygous (7/13 patients) C2orf71 mutations were identified. Eight of the mutations were novel. Truncation mutations were responsible in all cases. Nyctalopia was observed in less than 50% of patients. Visual acuity ranged from 20/20 to light perception. Severe visual loss was associated with atrophic maculopathy. Full-field ERG responses showed severe progressive cone-rod or rod-cone dysfunction. Typical fundus changes were progressive symmetrical retinopathy with an early mild maculopathy and patchy circular midperipheral RPE atrophy. Normal retinal lamination was preserved despite early disruption of the ellipsoid zone and RPE irregularities. Outer retinal tubulations were associated with better-preserved visual acuity. Conclusions: On the basis of our multicenter analysis, C2orf71 might represent a more frequently mutated gene in autosomal recessive retinitis pigmentosa in some populations. The phenotype analysis over a wide age range showed a variable and progressive retinal degeneration with early onset maculopathy and a better visual potential before the age of 30 years.

EYS Mutations Causing Autosomal Recessive Retinitis Pigmentosa: Changes of Retinal Structure and Function with Disease Progression.

Mutations in the EYS (eyes shut homolog) gene are a common cause of autosomal recessive (ar) retinitis pigmentosa (RP). Without a mammalian model of human EYS disease, there is limited understanding of details of disease expression and rates of progression of the retinal degeneration. We studied clinically and with chromatic static perimetry, spectral-domain optical coherence tomography (OCT), and en face autofluoresence imaging, a cohort of 15 patients (ages 12-51 at first visit), some of whom had longitudinal data of function and structure. Rod sensitivity was able to be measured by chromatic perimetry in most patients at their earliest visits and some patients retained patchy rod function into the fifth decade of life. As expected from RP, cone sensitivity persisted after rod function was no longer measurable. The photoreceptor nuclear layer of the central retina was abnormal except at the fovea in most patients at first visit. Perifoveal disease measured over a period of years indicated that photoreceptor structural loss was followed by dysmorphology of the inner retina and loss of retinal pigment epithelial integrity. Although there could be variability in severity, preliminary analyses of the rates of vision loss suggested that EYS is a more rapidly progressive disease than other ciliopathies causing arRP, such as USH2A and MAK.

MRI of thoracic outlet syndrome in children.

Thoracic outlet syndrome is caused by compression of the neurovascular bundle as it passes from the upper thorax to the axilla. The neurovascular bundle can be compressed by bony structures such as the first rib, cervical ribs or bone tubercles, or from soft-tissue abnormalities like a fibrous band, muscle hypertrophy or space-occupying lesion. Thoracic outlet syndrome commonly affects young adults but can be seen in the pediatric age group, especially in older children. Diagnosis is based on a holistic approach encompassing clinical features, physical examination findings including those triggered by various maneuvers, electromyography, nerve conduction studies and imaging. Imaging is performed to confirm the diagnosis, exclude mimics and classify thoracic outlet syndrome into neurogenic, arterial, venous or mixed causes. MRI and MR angiography are useful in this process. A complete MRI examination for suspected thoracic outlet syndrome should include the assessment of anatomy and any abnormalities using routine sequences, vessel assessment with the arms in adduction by MR angiography and assessment of dynamic compression of vessels with abduction of the arms. The purpose of this paper is to describe the anatomy of the thoracic outlet, causes of thoracic outlet syndrome, the MR imaging techniques used in its diagnosis and the principles of image interpretation.

The role of MR imaging in investigating isolated pediatric nystagmus.

BACKGROUND: The use of MRI in isolated pediatric nystagmus remains a gray area in clinical management. Many clinicians prefer to order an MRI to rule out intracranial pathology despite the lack of clinically significant findings in most cases. OBJECTIVE: To assess the yield of MR imaging in isolated pediatric nystagmus and define a management algorithm to minimize avoidable MRI referrals and streamline MRI protocols. MATERIALS AND METHODS: We reviewed the charts of 148 children who underwent neuro MRI for isolated nystagmus between January 2008 and September 2014. We noted nystagmus onset and clinical characteristics and compared them with the MRI features and visual electrophysiology results. RESULTS: We included 85 boys and 63 girls (total 148, average age at MRI 4.24 ± 4.19 years). Twenty-three (15.5%) children had abnormal intracranial findings on MRI including abnormal signal lesions (4.1%; n=6), Chiari I malformations (3.4%; n=5) and optic pathway glioma (2.0%; n=3). The time of onset of nystagmus was not associated with an abnormal MRI (P=0.2). Seventy children underwent visual electrophysiology testing but this test could not predict abnormality at MRI, either (P=0.12). CONCLUSION: Among children with isolated nystagmus, 15.5% had abnormalities on neuroimaging. Neither clinical characteristics of nystagmus nor the visual electrophysiology results allowed prediction of intracranial pathology. We were unable to formulate a management algorithm for the optimal sequence of investigations (MRI preceding visual electrophysiology or vice versa), but we discuss the use of gadolinium contrast agent and orbital sequences in isolated pediatric nystagmus.

Morphological patterns of indirect choroidal rupture on spectral domain optical coherence tomography.

PURPOSE: To evaluate the morphological types of indirect choroidal rupture (ICR) using spectral domain optical coherence tomography (SD-OCT). METHODS: This was a prospective interventional study of 18 eyes of 18 patients who presented with a history of blunt ocular trauma resulting in choroidal rupture. All patients underwent detailed ophthalmic evaluation and SD-OCT examination. RESULTS: Mean age of the patients was 32±9.6 years. Morphologically, two types of choroidal rupture were seen on SD-OCT. The first type seen (Type 1 ICR) was a forward protrusion of the retinal pigment epithelium-choriocapillaris (RPE-CC) layer with an acutely angled pyramid or dome shape. This was associated with either a small loss of continuity of the retinal pigment epithelium layer or elevated RPE-CC projection accompanied by a significant quantity of subretinal hemorrhage. The second type observed (Type 2 ICR) was a larger area of disruption of the RPE-CC layer, photoreceptor inner segment/outer segment junction, and external limiting membrane, with a posteriorly directed concave contour depression at that area and downward sliding of tissues into the defect. At presentation, ten eyes were observed to have Type 1 ICR and eight to have Type 2 ICR. Of the 18 eyes, one with Type 1 ICR and two with Type 2 ICR developed choroidal neovascularization (16.6%). CONCLUSION: Two distinct tomographic patterns of choroidal ruptures were identified on SD-OCT, which may allow ruptures to be classified into two morphological types. There are morphometric and clinical differences between the two types, which may help to prognosticate visual outcome and anticipate complications following choroidal ruptures.

Prevalence of Helicobacter pylori in patients with portal hypertensive gastropathy--a study from south India.

BACKGROUND: This study was done to ascertain the prevalence of Helicobacter pylori in patients with PHG and determine whether it contributed to the severity of the disease. MATERIAL/METHODS: A total of thirty-seven consecutive patients who presented with portal hypertensive gastropathy were included in the study. H. pylori status was determined by urease test and histology. The presence of at least one positive test was considered as a positive H. pylori state. Correlation analyses of H. pylori status with age, gender, alcohol consumption, and the site and severity of lesion were done. RESULTS: Sixteen of the 37 patients were positive for H. pylori. A linear trend with age was seen in H. pylori - infected patients. H. pylori positivity was higher in the second and third decades of life, although this did not reach statistical significance. The linear trend with age was similar to that of the control group. There was no association between H. pylori status and alcohol intake or the site of lesion. Twenty-sevenlpatients had endoscopic evidence of mill PHG, 9 had moderate and 1 severe. The H. pylori status was 52%, 22%, and 0% in patients with mild, moderate, and severe gastropathy, respectively, indicating an inverse relatioinship of severity of PHG with H. pylori colonization. CONCLUSIONS: Portal hypertensive gastropathy does not provide a favorable environment for the colonization of H. pylori. The decline in H. pylori positivity with the severity of PHG suggests that this bacterium is unlikely to contribute in the pathogenesis of congestive gastropathy and that hence there might be no need for its routine eradication in patients with PHG.