Oguchi disease with sectoral retinitis pigmentosa harboring adenine deletion at position 1147 in the arrestin gene

PURPOSE

To report a Japanese patient with Oguchi disease and sectoral retinitis pigmentosa harboring a homozygous adenine deletion at position 1147 (1147delA) in the arrestin gene.

METHOD

Case report.

RESULTS

In both eyes, golden discoloration with Mizuo-Nakamura phenomenon and tapetoretinal degeneration of the fundus were exhibited. Electroretinography showed abnormal a-wave and absent b-wave. The presence of 1147delA in the arrestin gene was demonstrated.

CONCLUSIONS

Our case provides further evidence of the close association of 1147delA in the arrestin gene in Japanese patients with Oguchi disease. Coexpression of both phenotypes of Oguchi disease and retinitis pigmentosa may suggest the possible involvement of additional defects of genes encoding the phototransduction proteins.

Night blindness in Sorsby's fundus dystrophy reversed by vitamin A

Sorsby's fundus dystrophy (SFD) is an autosomal dominant retinal degeneration caused by mutations in the tissue inhibitor of metalloproteinases-3 (TIMP3) gene. Mechanisms of the visual loss in SFD, however, remain unknown. In a SFD family with a novel TIMP3 point mutation, we tested a hypothesis that their night blindness is due to a chronic deprivation of vitamin A at the level of the photoreceptors caused by a thickened membrane barrier between the photoreceptor layer and its blood supply. Vitamin A at 50,000 IU/d was administered orally. Within a week, the night blindness disappeared in patients at early stages of disease. Nutritional night blindness is thus part of the pathophysiology of this genetic disease and vitamin A supplementation can lead to dramatic restoration of photoreceptor function.

[Histological examination of the human retina with congenital stationary night blindness]

We report histological findings of the retina from an eye with congenital stationary night blindness. The case was an 82-year-old woman who showed a Schubert-Bornschein type electroretinogram, and whose eye was enucleated due to orbital invasion of paranasal malignant melanoma. The retina had a disorganized outer plexiform layer with displaced nuclei of the outer and inner nuclear layer. There was also outward displacement of the cone nuclei, formation of hyaline and serous drusen, and disorganized retinal pigment epithelium as the histological changes due to aging. The histological abnormality seen in the outer nuclear layer could be responsible for the electrophysiological abnormality in this case.

Slowly progressive changes of the retina and retinal pigment epithelium in Briard dogs with hereditary retinal dystrophy. A morphological study

Seven eyes from 2 generations of Briard dogs (5 weeks--7 years old) with congenital night blindness and (in the second generation) impairment of day vision to varying degrees, were examined by light and electron microscopy. Specimens from 4 locations were studied: the central area, the midperiphery of the tapetal area, the upper periphery and the lower periphery. Disorientation of rod outer segment disc membranes was seen in the 5-week-old dog. Large electron-lucent inclusions were found in the RPE at 3.5 months of age. These inclusions occurred most frequently in the central and midperipheral-tapetal areas and seemed to increase in numbers and spread towards the periphery with increasing age. The content of these inclusions is not elucidated. Rod photoreceptor degeneration was apparent from 7 months of age and was most prominent in the peripheral areas. The cones were better preserved. The 7-year-old dog showed reduction of photoreceptors in the central and midperipheral-tapetal areas and almost complete photoreceptor degeneration in the periphery. This dog also showed severe changes of the inner retina in the peripheral fundus. It appears that these Briard dogs suffer from a very slowly progressive retinal degeneration, in which the photoreceptor degenerative changes do not correlate anatomically to the changes in the RPE cells. The disease seems to be different from the retinopathy described in the English Briards. It is not clear yet whether the lipid type of retinopathy found in American Briards is identical to the present disease.

No pigment deposition in a patient with advanced retinitis punctata albescens

A 51-year-old woman had had night blindness since childhood and a progressive visual field defect. She was the product of a consanguineous marriage. The patient also exhibited numerous whitish-yellow punctate spots with no pigment deposition in her fundi, nonrecordable electroretinographic responses after 30 min of dark adaptation, and constricted visual fields bilaterally. We believe that our patient may be a case of retinitis punctata albescens without pigment.

Disturbances in night vision after excimer laser photorefractive keratectomy

Eighty-four patients with up to -6.00 dioptres of myopia underwent photorefractive keratectomy (PRK), using 5.00 mm ablation zones. Three months post-operatively 38 (45%) complained of disturbances in night vision, compared with 21 (25%) pre-operatively. In the majority, these disturbances were regarded as negligible. However, 9 (11%) reported significant problems, defined as an inability to drive safely at night with the treated eye. At 12 months, 32 patients (38%) complained of impaired night vision, 4 (5%) of whom had significant problems. A series of measurements were performed to investigate the origins of these disturbances, especially in patients reporting significant problems. Visual impairment from forward scattered light was investigated using a computerised technique. Back scattered light was measured with a charge coupled device-camera system and a computer program was used to assess the degree of halation around a bright light source on a high-resolution monitor. Pupillary diameters were measured by infrared television pupillometry. At 6 months, those reporting a starburst effect around lights at night had small hyperopic shifts, minimal halos and high forward and back light scatter measurements. Patients who reported halo phenomena had large hyperopic shifts, little light scatter and large pupillary diameters. Of the 4 patients who reported significant disturbances at 12 months, all had persistent halo problems. Those with starburst effects in the early post-operative period noticed an improvement with time as their corneal haze gradually improved. Perturbations of night vision after PRK manifest as starbursts and halos around lights.(ABSTRACT TRUNCATED AT 250 WORDS)

Ultrastructural changes of the retina and the retinal pigment epithelium in Briard dogs with hereditary congenital night blindness and partial day blindness

The offspring of two Briard dogs (brother and sister) with congenital, clinically stationary night blindness showed an aggravation of the disease with severe impairment of day vision in addition to night blindness. This ultrastructural study was performed on four such second generation puppies at the age of 4 months. The neuroretina and retinal pigment epithelium (RPE) from four locations were studied: the central area (immediately temporal to the optic disc); the centre of the tapetal area; the upper periphery (border of tapetal area); and the lower periphery (non-tapetal area). The RPE showed large inclusions, seemingly lipid in nature, mainly in the central and tapetal areas of the retina. Small, membrane bound, electron-dense inclusions were scattered in the RPE cytoplasm in all areas examined. The small inclusions were found to be less numerous in normal than in affected dogs and may be lysosomal in nature. Forty to fifty percent of the rod outer segments in the tapetal area showed disorientation of the disc membranes, whereas the corresponding figures were 20-40% in the central and lower peripheral areas and 6-25% in the upper peripheral area. No structural abnormalities were found in the rod inner segments or synaptic bodies. The cones were better preserved. The inner retina appeared normal. These electron microscopic findings seem to correspond to a previously published electrophysiologic evaluation, indicating a defective and delayed rod function (virtually no scotopic a- and b-waves), a better preserved cone function (photopic flicker responses present, although reduced) and impaired RPE activity (a prominent, slow negative potential of long latency at the site of the c-wave). It appears that these Briard dogs, showing structural changes of the rod outer segments in addition to pigment epithelial inclusions, mainly located in the posterior pole, comprise a pigment epitheliopathy and retinopathy morphologically different from other hereditary canine retinopathies that have been described earlier in the literature and different from animal models of congenital night blindness.

Abnormal dark adaptation and rhodopsin kinetics in Sorsby's fundus dystrophy

Scotopic visual thresholds and time courses for dark adaptation were determined in eight patients with Sorsby's fundus dystrophy. Rhodopsin regeneration also was recorded in two. All patients had poor night vision and a visible yellow deposit at the level of Bruch's membrane that was confluent in the posterior pole. In retinal regions with the yellow deposit, scotopic thresholds were elevated, the rod-cone break was delayed or indistinct, the time courses for the rod portion of the dark adaptation curve was prolonged, and rhodopsin regeneration was slow in the one patient in whom measurements were made. In regions of ophthalmoscopically normal retina, dark adaptation was affected minimally, and in one patient, rhodopsin was regenerated at a normal rate. It was hypothesized that the abnormal dark adaptation and rhodopsin kinetics might be caused by reduced metabolic exchange across a thickened Bruch's membrane.

Correlations between electroretinography, morphology and function in retinitis pigmentosa

In a retrospective study, data from 116 patients suffering from different forms of retinitis pigmentosa were analysed, and 15 categories comprising altogether 34 symptoms or clinical signs were tabulated from each patient's record. The 15 categories evaluated were: visual acuity, visual field diameter, ring or central scotoma, nyctalopia, susceptibility to glare, refraction, cataract, electroretinography, colour of the optic disc, bone-spicule pigmentation of the retina, retinal vessel diameters, tapetoretinal reflex, sex, heredity, and age. Correlations between the tabulated 34 subcategories or symptoms were calculated. The results of a factorial analysis of the data showed a high number of highly significant correlations between the different categories. It seemed possible to discriminate between two groups of categories, with the members of each group being closely correlated but correlations with members of the other group being much smaller, if not nonexistent. We tentatively associated the first group with the functional state of the central retina and the second group with the state of the peripheral retina.

Long-term follow-up of the physiologic abnormalities and fundus changes in fundus albipunctatus

Fundus albipunctatus (FA) is considered to be a congenital stationary night-blinding disorder, but there has been no electrophysiologic or photographic documentation of long stability or change. This documentation is presented for two cases followed for 13 to 14 years. The physiologic (functional) deficits appeared to be stable, in support of the concept that FA is not a progressive dystrophy. However, the fundus lesions evolved in appearance from flecks in childhood to relatively permanent punctate dots that increase in number over the years.

Clinical and serum lipid findings in a large family with autosomal dominant retinitis pigmentosa

Retinitis pigmentosa, of unknown cause, has recently been associated with decreased amounts of the polyunsaturated fatty acid, docosahexaenoic acid, in the plasma of affected as compared with unaffected relatives. It has been suggested that this finding may serve as a marker for the disease and might indicate alterations in photoreceptor cell metabolism. The authors studied 54 members of a family with dominantly inherited retinitis pigmentosa in five generations. In addition to the typical clinical findings of retinitis pigmentosa, eight persons also had a bull's eye maculopathy, and four persons had uni- or bilateral optic nerve drusen. When the authors determined the plasma fatty acid and lipid contents, they saw the expected age-related effect on cholesterol and triglycerides, but an unexpected, significant reduction in fatty acids in the unaffected controls as compared with persons with retinitis pigmentosa. The authors' results emphasize the heterogeneity of phenotypic expression of retinitis pigmentosa within a single family.

[New findings in Oguchi disease]

The authors report on clinical and electrophysiological studies of a patient with Type I Oguchi's disease. Numerous small pigmentations of the retinal pigment epithelium (RPE) causing focal disruption of the Oguchi reflex were observed, a phenomenon which has not previously been reported. Consistent with reports of pathologic changes in the RPE, an abnormal electro-oculogram (EOG) was recorded in this patient. On the basis of this information, the pigmentations were interpreted as dysplastic changes.

Congenital stationary night blindness with myopia: a clinico-pathologic study

The left eye of a 77 year old male patient was enucleated because of absolute glaucoma. This eye showed subnormal electroretinogram (ERG) and oscillatory potentials preoperatively, but the other eye showed Schubert-Bornschein type ERG and monophasic dark adaptation curve. Light and electron microscopic studies of the left eye showed a normal arrangement of discs of rod outer segments, normal synaptic ends of the photoreceptors, and complete loss of ganglion cells. From the subnormal ERG in the left eye we assumed it was originally Schubert-Bornschein type ERG but inverted to subnormal type ERG following the loss of inhibitory mechanisms. Thus we propose that the cause of night blindness in congenital stationary cases with Schubert-Bornschein type ERG may be related to the mechanisms inhibitory to cells of the bipolar layer.

Choroideremia in a genotypically normal female. A case report

A 10-year-old girl demonstrated advanced choroideremia. She had decreased visual acuity, high myopia, and characteristic fundus findings of choroideremia. Her ERG, dark adaptation, visual fields, and fluorescein angiogram were all abnormal; the results were consistent with choroideremia. Her chromosome studies revealed that she was a genotypically normal female. Her parents were examined ophthalmologically and found to be normal.

Loss of electroretinographic oscillatory potentials, optic atrophy, and dysplasia in congenital stationary night blindness

New criteria for diagnosing congenital stationary night blindness include loss of the oscillatory potentials in the photopic and bright-flash dark-adapted electroretinogram, and atrophy or dysplastic changes, or both, in the optic nerve head. Ten patients (seven male and three female, ranging in age from 6 to 19 years) had typical findings of congenital stationary night blindness including congenital nonprogressive nyctalopia, no pigmentary retinopathy, and full visual fields consistent with myopia. Visual acuities ranged from 20/30 to 20/60, though one patient had a visual acuity of 20/200. Most patients had histories of strabismus. The photopic electroretinograms were subnormal. Of the male patients, five had tilted optic disks with temporal portions of the nerve missing, and two had misshapen nerve heads. The three female patients had pallor of the optic disk without evidence of tilt.

Bitot's spots responsive and nonresponsive to vitamin A. Clinicopathologic correlations

Conjunctival biopsy specimens from patients with Bitot's spot responsive and nonresponsive to vitamin A were studied by light and electron microscopy. In both types, the lesions demonstrated keratinization with granular cells, irregular maturation, inflammatory infiltration of the conjunctival substantia propria, and loss of goblet cells. Only in the responsive cases were these changes generalized. Prominent Bitot's spots represented massive accumulations of Gram-positive bacilli and keratin debris. Responsive cases improved histologically within seven days of treatment, and goblet cells began to return within two weeks. These results support our previous suggestions that there is little basis for attempting to differentiate, clinically, between the two types of lesions and that at least some nonresponsive lesions represent a persistent metaplastic change induced during a prior episode of vitamin A deficiency.

Correlation of clinicopathologic findings in a patient. Congenital night blindness, branch retinal vein occlusion, cilioretinal artery, drusen of the optic nerve head, and intraretinal pigmented lesion

The ocular clinicopathologic features of this unique patient were congenital stationary night blindness, drusen of the optic nerve head, cilioretinal artery, intraretinal pigmented lesion, and branch retinal vein occlusion. Photocoagulation therapy led to total disappearance of the neovascular tissue, clinically and histopathologically. Histopathologic examination showed an occluded branch vein associated with a sclerotic retinal arteriole. Peripheral to the site of venous occlusion, inner ischemic retinal atrophy was present. The normal complement of rod and cone photoreceptors supports the view that the night blindness in this case was an abnormality in the neural transmission and not on a morphological basis. The pigmented intraretinal lesion proved to be a localized area of retinal and choroidal neovascularization with anastomosis and secondary retinal pigment epithelial hyperplasia. This lesion was identical to Fuchs' dot of myopia but out patient was hyperopic.

Histopathology of Goldmann-Favre syndrome obtained by full-thickness eye-wall biopsy

The first histopathologic specimen form the eye of a patient with Goldmann-Favre syndrome was obtained by full-thickness eye-wall biopsy. Diagnosis was established by an early history of night blindness, characteristic clinical features including atypical pigmentary retinopathy, peripheral retinoschisis, opaque "sclerotic-appearing" peripheral retinal vessels, vitreous changes including liquefaction and condensed vitreous bands and a non-detectable electroretinogram (ERG). Histopathologic changes from a 4 mm peripheral area included diffuse degenerative changes involving predominantly the sensory retinal layers with a relatively normal pigment epithelium and choroid. Vascular changes included thickened retinal vessel basement membranes and areas of vascular occlusion. These findings are compatible with a primary photoreceptor involvement in addition to a vascular component. A thick preretinal membrane of glial tissue was an additional finding.

Diagnostic features of the Favre-Goldmann syndrome

Extensive retinal vascular disease was noted in three patients from two families with Favre-Goldmann syndrome. In addition to classical features they had pronounced leakage from some retinal vessels. Vessels were either opaque ('sclerotic') or non-perfused. Cystoid macular oedema was a contributing cause of decreased vision. Two of the three patients showed a discrepancy on electroretinography between single-flash photopic amplitudes and flicker fusion frequency. This may be characteristic of Favre-Goldmann syndrome.