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Several analyses are conducted to determine the various genes that are mutated in the patients suffering from autosomal-recessive complete congenital stationary night blindness. The results demonstrate that TRPM1 is the most commonly mutated gene.

Purpose To analyze the retinal structure in patients with X-linked retinoschisis (XLRS) using spectral-domain OCT and to correlate the morphologic findings with visual acuity, electroretinographic results, and patient age. Design Retrospective, observational study. Participants Data from 52 consecutive male patients with molecularly confirmed XLRS were collected retrospectively. Methods Complete clinical evaluation included best-corrected visual acuity, full-field electroretinography, fundus photography, spectral-domain OCT, and fundus autofluorescence. Spectral-domain OCT images were analyzed to determine full thickness of the retina and tomographic structural changes. Main Outcome Measures Relationships between age, OCT, and visual acuity were assessed. Results One hundred four eyes of 52 patients were included. The mean age at inclusion was 24±15 years (range, 3–57 years). The best-corrected visual acuity ranged from no light perception to 0.1 logarithm of the minimum angle of resolution (mean, 0.6±0.38 logarithm of the minimum angle of resolution). Macular schisis was found in 88% of eyes and macular atrophy was found in 11% of eyes, whereas peripheral schisis was present in 30% of eyes. A spoke-wheel pattern of high and low intensity was the most frequently observed fundus autofluorescence abnormality (51/94 eyes [54%]). The b-to-a amplitude ratio on bright-flash dark-adapted electroretinography was reduced significantly in 45 of 64 eyes (70%). Spectral-domain OCT was available for 97 eyes and showed foveoschisis in 76 of 97 eyes (78%), parafoveal schisis in 10 of 97 eyes (10%), and foveal atrophy in 11 of 97 eyes (11%). Mean central macular thickness (CMT) was of 373.6±140 μm. Cystoid changes were localized mainly in the inner nuclear layer (85/97 eyes [88%]). Qualitative defects in photoreceptor structures were found in most eyes (79/97 eyes [81%]), and the most frequent abnormality was an interruption of the photoreceptor cell outer segment tips (79/79 eyes [100%]). Older age correlated well with lower CMT (correlation coefficient [CC], –0.44; P < 0.001) and with lower photoreceptor outer segment (PROS) length (CC, –0.42; P < 0.001). Lower visual acuity correlated strongly with lower PROS length (CC, –0.53; P < 0.001). Conclusions This study underlined the wide variety of clinical features of XLRS. It highlighted the correlation between visual acuity, patient age, and OCT features, emphasizing the relevance of the latter as potential outcome measure in clinical trials. [ABSTRACT FROM AUTHOR]

In retinitis pigmentosa (RP), a majority of causative mutations affect genes solely expressed in rods; however, cone degeneration inevitably follows rod cell loss. Following transplantation and in vitro studies, we demonstrated the role of photoreceptor cell paracrine interactions and identified a Rod-derived Cone Viability Factor (RdCVF), which increases cone survival. In order to establish the clinical relevance of such mechanism, we assessed the functional benefit afforded by the injection of this factor in a frequent type of rhodopsin mutation, the P23H rat. In this model of autosomal dominant RP, RdCVF expression decreases in parallel with primary rod degeneration, which is followed by cone loss. RdCVF protein injections induced an increase in cone cell number and, more important, a further increase in the corresponding electroretinogram (ERG). These results indicate that RdCVF can not only rescue cones but also preserve significantly their function. Interestingly, the higher amplitude of the functional versus the survival effect of RdCVF on cones indicates that RdCVF is acting more directly on cone function. The demonstration at the functional level of the therapeutic potential of RdCVF in the most frequent of dominant RP mutations paves the way toward the use of RdCVF for preserving central vision in many RP patients.Molecular Therapy (2009) 17 5, 787–795 doi:10.1038/mt.2009.28 [ABSTRACT FROM AUTHOR]

This mini-review summarizes our current knowledge concerning the age-related changes that affect the retina. Over the last 10 years, our understanding of the genetics of hereditary retinal diseases has improved considerably. However, the modifications that occur in the retina as a result of aging are still under investigation. In this review, we place particular emphasis on the normal retinal alterations that occur with aging (gene modulation; psychophysical, structural and cellular alterations). We describe the events that occur during the pathological aging process, such as in age-related macular degeneration. Understanding these different modifications is essential if we are to find key players on which to base therapeutic interventions that may help to prevent the passage of normal aging process to the pathological aging process. [Copyright &y& Elsevier]

Loss of photoreceptors in atrophic age-related macular degeneration results in severe visual impairment, although some peripheral vision is retained. To restore central vision without compromising the residual peripheral field, we developed a wireless photovoltaic retinal implant (PRIMA; Pixium Vision, Paris, France) in which pixels convert images projected from video glasses using near-infrared light into electric current to stimulate the nearby inner retinal neurons. We carried out a first-in-human clinical trial to test the safety and efficacy of the prosthesis in patients with geographic atrophy (ClinicalTrials.gov identifier, NCT03333954). Five patients with geographic atrophy zone of at least 3 optic disc diameters, no foveal light perception, and best-corrected visual acuity of 20/400 to 20/1000 in the worse-seeing study eye. The 2-mm wide, 30-μm thick chip, containing 378 pixels (each 100 μm in diameter), was implanted subretinally in the area of atrophy (absolute scotoma). Anatomic outcomes were assessed with fundus photography and OCT for up to 12 months of follow-up. Prosthetic vision was assessed by mapping light perception, bar orientation, letter recognition, and Landolt C acuity. In all patients, the prosthesis was implanted successfully under the macula, although in 2 patients, it was implanted in unintended locations: within the choroid and off center by 2 mm. All 5 patients could perceive white-yellow prosthetic visual patterns with adjustable brightness in the previous scotomata. The 3 with optimal placement of the implant demonstrated prosthetic acuity of 20/460 to 20/550, and the patient with the off-center implant demonstrated 20/800 acuity. Residual natural acuity did not decrease after implantation in any patient. Implantation of the PRIMA did not decrease the residual natural acuity, and it restored visual sensitivity in the former scotoma in each of the 5 patients. In 3 patients with the proper placement of the chip, prosthetic visual acuity was only 10% to 30% less than the level expected from the pixel pitch (20/420). Therefore, the use of optical or electronic magnification in the glasses as well as smaller pixels in future implants may improve visual acuity even further. [ABSTRACT FROM AUTHOR]

Introduction Les objectifs de notre étude sont d'étudier l'impact de la dégénérescence maculaire liée à l'âge (DMLA) sur le contrôle postural grâce à une analyse temporelle des oscillations du centre de pression ; puis d'étudier l'impact de la dominance oculaire sur la stabilité posturale des sujets avec DMLA selon différentes conditions visuelles. Nos hypothèses sont que les sujets avec DMLA uni- ou bilatérale présentent des stratégies de compensation posturale différentes, et que les sujets avec DMLA sont plus stables en condition œil dominant ouvert qu'en condition les deux yeux ouverts. Matériels et méthodes La stabilité posturale a été enregistrée avec la plateforme de force Framiral® chez dix sujets avec DMLA unilatérale, dix sujets avec DMLA bilatérale et dix sujets sains du même âge. Sept conditions visuelles ont été testées : fixation d'une cible lumineuse yeux ouverts (YO), œil dominant ouvert (OD), œil non dominant ouvert (OND), yeux fermés (YF) et vision perturbée (VP) par stimuli optocinétiques (VP-YO, VP-OD, VP-OND). Les paramètres évalués sont la surface et la vitesse de déplacement du centre de pression, et l'indice d'instabilité posturale (IIP). Résultats L'IIP est majoré chez les sujets atteints de DMLA unilatérale et bilatérale. Les sujets avec DMLA unilatérale sont plus stables en condition VP-OD qu'en condition VP-YO. Les sujets sains en condition YF sont plus stables que les sujets avec DMLA. Conclusion Nos données suggèrent que les sujets avec DMLA bilatérale présentent des stratégies de compensation posturale différentes des sujets avec DMLA unilatérale. D'autres études sont nécessaires pour affiner ces résultats et développer des techniques de rééducation. [ABSTRACT FROM AUTHOR]