Solar retinopathy is an injury of the retinal photoreceptors due to excessive exposure to the solar radiation. Diagnosis of the disease is challenging and requires combination of a detailed history and imaging modalities. This case report focuses on a 55-year-old fruit picker with an irreversible central scotoma of the right eye. A diagnosis of solar retinopathy was made based on history but mainly by several imaging modalities, such as optical coherence tomography (OCT), infrared (IF) imaging of the fundus and fundus autofluorescence (FAF). Electroretinogram (ERG)showed flattened and reduced waves in both scotopic and photopic response. Fundus angiography (FA) revealed no obvious telangectatic vessels. In conclusion, solar retinopathy is a disease where multimodal imaging may play an important role in the diagnosis. The condition may be irreversible thus advocating protective eyewear is mandatory in patients who are chronically exposed to the sun.
Photoreceptor Cells, Vertebrate

No abstract available.
Animals ; Photoreceptor Cells* ; Rats* ; Retina*

Experimental retinal changes of intraperitoneal copper sulphate administration were studied with the electron microscope. Rabbits were given intraperitoneally copper sulphate in doses of 2.5 mg every day. The results were as follows: 1. Swelling and degeneration of inner segment of the photoreceptor cells were observed after 4 weeks of copper administration. There were no chages in the pigment epithelium. 2. Phagosomes, phagoyslosomes and melanolysosomes were observed in the pigment epithelium and subretinal space after 6 weeks of copper administration. 3. Copper sulphate primarily involved the rod and cone layer and the changes of the pigment epithelium were late and secondary. These findings were similar with those of the retintis pigmentosa.
Copper* ; Epithelium ; Phagosomes ; Photoreceptor Cells ; Rabbits ; Retinaldehyde*

The migration of photoreceptors into the subretinal space has been reported to occur in developing and aged rat retina, in aged human retina, in detached owl monkey, and in detached cat retina. Subretinal photoreceptor cells have been observed in aphakic-vitrectomized rabbit eyes with or without intravitreal saline or antibiotic injection. Variety of photoreceptor cell nuclei can be distinguished. The nuclei of photoreceptor cells change their shape so as to pass easily through the juncition and thereafter they returned to their original shape in sub retinal space. The mechanisms and biological significance of this phenomenon are not yet certain, but it may by one of the important factors contributing to decreased vision with aging.
Aging ; Animals ; Aotidae ; Cats ; Humans ; Photoreceptor Cells* ; Rats ; Retina* ; Retinaldehyde

To investigate the retinal toxicity of ciprofloxacin on retina, 23 New Zealand white rabbits received vitrectomy with intravitreal infusion that contain of 1 g/ml, 2 g/ml, 5 g/ml, 10 g/ml, and 25 g/ml of ciprofloxacin(20 eyes) or balanced salt solution(BSS) only(3 eyes). In transmission elctron microscope, no disintegration of all retinal layers and slightly irregular pattern of disc of outer segment of rod were observed in 1, 2 and 5 g/ml of ciprofloxacin groups at 14 days postinfusion. In concentration of 10 g/ml or greater, retina showed destroyed inner and outer segment of the photoreceptor cells, pyknotic nuclei in the outer nuclear layer, lucent vacoules and pigment granules in apical cytoplasm of the retinal pigment epithelium(RPE), loss of photoreceptor outer segment-RPE integration. This study suggest that infusion with 5 g/ml or less of ciprofloxacin may be safe when used in the treatment of bacterial endophthalmitis.
Ciprofloxacin* ; Cytoplasm ; Endophthalmitis ; Photoreceptor Cells ; Rabbits ; Retina* ; Retinaldehyde ; Vitrectomy

In order to study the functional and structural alterations of the retina in SD rat model after methanol intoxication, 35 rats were divided randomly into five groups administrated with saline, 3-day high dose, 7-day high dose, 3-day low dose and 7-day low dose methanol separately. The retinal function of each group was assessed by flash electroretinogram (F-ERG) 3 and 7 days after methanol poisoning. The microstructure and ultrastructure of the retina were observed at the same time. The high-dose methanol intoxication induced irreversible retinal functional and structural damages 3 days after poisoning, which included prolonged latency and reduced amplitude of the Max-reaction of F-ERG. These injuries were aggravated 7 days after poisoning. Meanwhile, the latency and amplitude of the Cone-reaction of F-ERG were also affected 3 days after poisoning, but there were no further worsening tendency 7 days after poisoning. The retinal histological analysis showed cellular edema, heteromorphy and disarrangement, tissular loosen of the inner nuclear layer and photoreceptors layer. The mitochondrial damage began at the photoreceptors layer and developed further into the inner nuclear layer. The low-dose methanol intoxication only caused transient damage of the retina. Our results showed that the function and structure of the photoreceptor and inner nuclear layer were the primary target of methanol intoxication and that the rod cells were more sensitive to methanol intoxication than the cone cells. The mitochondrial damage developed from outer layer to inner layer of the retina.
Animals ; Edema/pathology* ; Electroretinography ; Forensic Medicine ; Male ; Methanol/poisoning* ; Mitochondria/pathology* ; Photoreceptor Cells/pathology* ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Retina/physiopathology* ; Retinal Cone Photoreceptor Cells/pathology* ; Retinal Diseases/pathology* ; Retinal Rod Photoreceptor Cells/pathology* ; Time Factors

The authors investigated the possibility of transplantion of cultured retinal pigment epithelial cell to normal pigmented rabbit retina. Focal retinal detachment was made in the pigment rabbit retina, and the cultured RPE cells were injected into subretinal space. The neural retina spontaneously rettached withim 6 days. At 4 weeks after tranplantation, eyes were enucleated and examined with light-microscopy and electron-microscopy. The transplanted RPE cells were proliferated with multilayer in electronmicroscopic finding, and the tight-junction was found between proliferative RPE cells. The outer segment and nucleus of photoreceptor cell were well preserved in microscopic finding. As a result, the cultured RPE cells can be sucessfully transplanted to normal pigmented rabbit retina, and photoreceptor cell was not changed after transplantation.
Epithelial Cells ; Photoreceptor Cells ; Retina ; Retinal Detachment ; Retinal Pigment Epithelium* ; Retinaldehyde*

In order to simulate the hemorrhagic detachment stage of disciform macular degeneration, fresh blood was injected into the subretinal space of albino rabbits. In control group, the natural course of subretinal hemorrhage was studied with the ophthalmoscope and by electron microscopy. In experimental group, to study the effect of surgical intervention of the subretinal hemorrhage, a retinotomy was performed at the edge of the detached retina and the subretinal blood was removed by aspiration. And then the histopathologic change of the retina was exam ined by electron microscopy in both groups preceded by the ophthalmoscopic examination. In control group, between 12 hours and 4 days, there was partial damage of the photoreceptor cells characterized by destruction of the outer segment and swelling of mitochondria of the inner segment. In seven days after injection, irreversible retinal destruction was observed. In experimental group, two days after removal of subretinal hemorrhage in two hours following subretinal injection of blood, the outer segment was lost and destructed. Two days after removal of subretinal hemorrhage in five days following subretinal injection of blood, hydropic swelling and vacuolization of visual cells were characteristic. However there was no significant difference in the histopathologic change of retina between two groups.
Hemorrhage* ; Macular Degeneration ; Microscopy, Electron ; Mitochondria ; Ophthalmoscopes ; Photoreceptor Cells ; Rabbits ; Retina ; Retinaldehyde

PURPOSE: To identify a subtype of cone photoreceptor in the mammalian retina using enzyme histochemical method. METHODS: In human, rabbits and cats, identification of cone photoreceptor was tried with carbonic anhydrase after retinal tissue isolation and section. RESULTS: In human, subtype of cone photoreceptor was identified. In rabbits, one type of carbonic anhydrase negative regular cell was detected and suspected as rod cells. In cats, only blue cone cell and rod cell were detected and no red-green cone cell was detected. CONCLUSIONS: In cats and rabbits, identification of red-green cone cell and blue cone cell was difficult. So, enzyme histochemical identification of cone photoreceptor using carbonic anhydrase need more research to imply in mammalian retina.
Animals ; Carbonic Anhydrases ; Cats ; Humans ; Rabbits ; Retina* ; Retinal Cone Photoreceptor Cells* ; Retinaldehyde

Authors evaluated the retinal toxicity of high dose (2mg/0.1ml, 4mg/0.1ml) intravitreal ganciclovir injection in rabbit eye with light microscopy and electron microscopy. The results were as follows: In twenty-four hours after 2.0mg/0.1ml intravitreal injection group, edema of outer cells in inner nuclear layer were visualized under electron microscopy. These findings were disappeared after 3 days. In 4.0mg/0.1ml intravitreal injection group, edema of outer cells in inner nuclear layer were visualized at 24 hours after injection. Edema of outer cells in inner nuclear layer and axonal swelling of outer plexiform layer and upper border cells of outer nuclear layer were demonstrated at third and seventh day after injection. We observed more severe changes at seventh day than third day, and fragmentation of inner and outer segments in photoreceptor cells and presence of macrophage corresponding site of subretinal space. So, it suggests that 4.0mg/0.1ml intravitreal ganciclovir injection has mild reversible retinal toxicity.
Axons ; Edema ; Ganciclovir* ; Intravitreal Injections ; Macrophages ; Microscopy ; Microscopy, Electron ; Photoreceptor Cells ; Retinaldehyde*