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The separation of outer retinal photoreceptors in patients with toxoplasmosis chorioretinitis was first named bacillary layer detachment (BALAD), which was manifested as a split at the level of the photoreceptor inner segment myoid creating a distinctive intraretinal cavity in optical coherence tomography.Subsequently BALAD has been reported by many researchers in different diseases.In the outer retina, the myoid is a relatively weak structure in photoreceptor inner segment.When the outward force that promotes the attachment of the photoreceptor outer segment to the retinal pigment epithelium exceeds the tensile strength of the photoreceptor inner segment myoid, the myoid zone splits and BALAD occurs.BALAD has its unique multimodal imaging characteristics, and the identification of it can provide a new idea for the diagnosis, detection and treatment of ocular diseases.This paper reviewed the development of BALAD nomenclature, its anatomical structure, pathophysiological mechanism and multimodal image features.

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The Tet-ON system is an important molecular tool for temporally and spatially-controlled inducible gene expression. Here, we developed a Tet-ON system to induce transgene expression specifically in the rod photoreceptors of medaka fish. Our modified reverse tetracycline-controlled transcriptional transactivator (rtTAm) with 5 amino acid substitutions dramatically improved the leakiness of the transgene in medaka fish. We generated a transgenic line carrying a self-reporting vector with the rtTAm gene driven by the Xenopus rhodopsin promoter and a tetracycline response element (TRE) followed by the green fluorescent protein (GFP) gene. We demonstrated that GFP fluorescence was restricted to the rod photoreceptors in the presence of doxycycline in larval fish (9 days post-fertilization). The GFP fluorescence intensity was enhanced with longer durations of doxycycline treatment up to 72 h and in a dose-dependent manner (5-45 µg/ml). These findings demonstrate that the Tet-ON system using rtTAm allows for spatiotemporal control of transgene expression, at least in the rod photoreceptors, in medaka fish.

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A 21-year-old Caucasian man presented with a complaint of nyctalopia. Visual acuity in both eyes was 20/20 and anterior segment biomicroscopy results were unremarkable. Fundoscopy revealed peripheral avascular zones, minimal peripheral retinal exudation from the retinal vessels, peripheral retinal telangiectasias and anastomosis in both eyes, and retinal vascular dragging toward the temporal periphery in both eyes. Full field electroretinography showed that rod responses were almost absent and that cone responses were reduced. Macular optical coherence tomography showed normal structure in both eyes. Vascular changes were attributed to a subclinical form of familial exudative vitreoretinopathy. This was an interesting case due to the association of familial exudative vitreoretinopathy with rod-cone dystrophy.

Um homem caucasiano de 21 anos foi avaliado com queixa de nictalopia. A acuidade visual era 20/20 em ambos os olhos. Biomicroscopia do segmento anterior era normal. A fundoscopia revelava zonas avasculares periféricas, exsudação mínima dos vasos retinianos periféricos da retina, telangiectasias da retina periférica com anastomoses em ambos os olhos e deslocamento vascular da retina em direção a periferia temporal em ambos os olhos. O eletrorretinograma (ERG) de campo total apresentava respostas de bastonetes praticamente indetectáveis e redução das respostas de cones. A tomografia de coerência óptica (OCT) macular mostrava estrutura normal em AO. As alterações vasculares foram atribuídas à forma subclínica da vitreorretinopatia exsudativa familiar. Este é um caso interessante com a associação de vitreoretinopatia exsudativa familiar e distrofia de cones e bastonetes (RCD).

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A persistent nineteenth-century urban legend was the notion that photograph-like images of the last-seen object or person would be preserved in the eyes of the dead. This popular notion followed technological developments (the daguerreotype and ophthalmoscope) that antedated by decades a basic understanding of retinal physiology. From 1876 to 1877, Boll described photochemical bleaching of the retina and produced a crude retinal image that remained briefly visible after death in an experimental animal. From 1877 to 1881, Kühne elaborated the processes involved in photochemical transduction, and created more complex retinal images, or "optograms," that were visible after the death of experimental animals under special laboratory circumstances. In 1880, Kühne reported the first human "optogram" when he examined the eyes following the state execution of a convicted murderer. Although the work of these physiologists increased public interest in "optography" as a potential tool in forensic investigations, Kühne and his student, Ayres, concluded after an extensive series of investigations that optography would never be useful for this purpose. Nevertheless, because of the prior tantalizing results, optography became a frequent consideration in speculative news reports of sensational unsolved murders, and as a plot device in works of fiction, some quite fantastical. Fictional portrayals included works by Rudyard Kipling and Jules Verne. Despite denouncement of optography for forensic investigations by Kühne, and by numerous physicians, the general public and mass media continued to press for examination of the retinae of murder victims well into the twentieth century, particularly in high-profile unsolved cases.

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