Hemeralopia

Abstract: PURPOSE: To report a large, consanguineous Algerian family affected with Leber congenital amaurosis (LCA) or early-onset retinal degeneration (EORD). METHODS: All accessible family members underwent a complete ophthalmic examination, and blood was obtained for DNA extraction. Homozygosity mapping was performed with markers flanking 12 loci associated with LCA. The 15 exons of TULP1 were sequenced. RESULTS: Seven of 30 examined family members were affected, including five with EORD and two with LCA. All patients had nystagmus, hemeralopia, mild myopia, and low visual acuity without photophobia. Fundus features were variable among EORD patients: typical spicular retinitis pigmentosa or clumped pigmented retinopathy with age-dependent macular involvement. A salt-and-pepper retinopathy with midperipheral retinal pigment epithelium (RPE) atrophy was present in the older patients with LCA, whereas the retina appeared virtually normal in the younger ones. Both scotopic and photopic electroretinograms were nondetectable. Fundus imaging revealed a perifoveal ring of increased fundus autofluorescence (FAF) in the proband, and optical coherence tomography disclosed a thinned retina, mainly due to photoreceptor loss. Linkage analysis identified a region of homozygosity on chromosome 6, region p21.3, and mutation screening revealed a novel 6-base in-frame duplication, in the TULP1 gene. CONCLUSIONS: Mutation in the TULP1 gene is a rare cause of LCA/EORD, with only 14 mutations reported so far. The observed intrafamilial phenotypic variability could be attributed to disease progression or possibly modifier alleles. This study provides the first description of FAF and quantitative reflectivity profiles in TULP1-related retinopathy.

Abstract: Night blindness or hemeralopia as the result of qualitatively inadequate dietaries has been recognized from the time of Hippocrates.1However, for many years this condition was considered of rare occurrence except in certain communities or during periods of fasting, famine or war. The recent reports by Jeans and his co-workers,2Jeghers,3Park,4Corlette and his associates,5Barborka6and others suggest that this condition is relatively frequent. The literature is in agreement as to the infrequency of frank cases of night blindness associated with xerophthalmia, xerosis and keratomalacia in the United States. Each of these workers was tested for impaired dark adaptation by means of an instrument designed for clinical use and known as the biophotometer. This instrument purports to determine vitamin A deficiency by measurement of the degree of impairment of the light threshold and the rate and degree of dark adaptation. Other means

Abstract: In 1909, 2 years after the famous publication by Nettleship, a large family with congenital stationary night-blindness of the ‘Nougaret type’ was published by the Danish district surgeon, Sigurd Rambusch In 1990 the ‘Rambusch family’, still resident in the original area, was sought out and rediscovered, at which time the reconstructed part of the pedigree comprised more than 200 affected persons in 11 generations Dark adaptometry and electroretinography were performed on a few affected family members, including a descendant with a uniocular affection The pedigree is presented and recordings of dark adaptation courses and electroretinographical responses from a few family members are demonstrated