Sector retinitis pigmentosa: a fluorescein angiographic study.

Flourescein angiography has been proved to be of value in the study of the chorioretinal abnormaliteis in sector retinitis pigmentosa. The findings from two patients, one being in an early and the other in a more advanced stage were analyzed. The pigment epithelium was found to be disturbed in a larger area than visible by ophthalmoscopy. In the impaired quadrant the retinal vessels were narrowed showing delayed and slow dye transit. Through the discolorated pigment epithelium leaky choriocapillaries were disclosed. Moreover, in the severly affected patient, areas missing choriocapillar perfusion and retinal circulation were also detected.     

Retinal pigmentary changes in chronic uveitis mimicking retinitis pigmentosa

Graefe's Archive for Clinical and Experimental Ophthalmology - To present retinal pigmentary changes mimicking retinitis pigmentosa (RP) as a finding of advanced uveitis. We retrospectively...     

Retinal regeneration and stem cell therapy in retinitis pigmentosa

Retinitis pigmentosa (RP) is the leading cause of hereditary blindness, and there is currently no available treatment that can either significantly slow the progression of this disease or restore lost vision. Amphibians and birds exhibit different strategies for retinal regeneration, including the proliferation of cells in the ciliary margin and transdifferentiation of the retinal pigment epithelium (RPE) and Muller glia. The mammalian retina does not have the innate ability to regenerate damaged retina, but research is actively exploring pathways that promote endogenous regeneration. Because the inner retinal architecture is largely preserved, even in advanced cases of RP, an alternative is to replace the degenerated photoreceptor cells, thereby replenishing the photoreceptor population. The transplantation of embryonic stem cells, induced pluripotent stem cells, embryonic retinal progenitors (postmitotic photoreceptor precursors), and hippocampal neuronal progenitors have been investigated for this purpose. The encouraging results demonstrate the integration and possible functional connection between the transplanted cells and the inner retinal circuitry of the host. In this review, we summarize recent advancements in this field and their potential for the treatment of RP and other retinal degenerations.     

Retinal hemangioma-like lesions in eyes with retinitis pigmentosa.

The authors report two patients with bilateral vascular masses of the peripheral retina associated with primary pigmentary dystrophy of the retina (retinitis pigmentosa). Although they are most similar to the retinal capillary hemangiomas of von Hippel, the affected patients had no clinical history or clinical findings suggestive of that syndrome. They differ from the calcified retinal hamartomas that have been associated with retinitis pigmentosa because they do not show the extensive telangiectasia and exudation seen with the exudative retinopathy that has been described with retinitis pigmentosa. They do not show the fluorescein angiographic pattern that characterizes peripheral choroidal neovascularization. Their main complication seems to be vitreous hemorrhage rather than exudative retinopathy. The authors discuss the possible relationship of these acquired retinal vascular masses to the retinitis pigmentosa.     

Retinal histopathology of a carrier of X-chromosome-linked retinitis pigmentosa

Autopsy eyes were examined from a 79-year-old female carrier of X-chromosome-linked retinitis pigmentosa. At age 78 years, she had no visual symptoms but had intraretinal bone spicule pigmentation in the nasal and inferior periphery of both eyes. Rods, cones, and pigment epithelium in the central retina appeared normal. In the midperiphery, patches with advanced photoreceptor cell degeneration were observed overlying pigment epithelium containing melanolysosomes. Within these patches, rods and cones were reduced in number or absent, and pigment epithelial cells abutted the external limiting membrane. A precipitous decline in rod nuclei was observed in transitional zones between areas of apparently normal photoreceptors and areas of absent photoreceptors. In the far periphery, large areas lacked photoreceptors and pigment epithelium. Histopathologic findings in this elderly carrier are compared with those previously described in a 24-year-old man with X-chromosome-linked retinitis pigmentosa.     

Retinal arteriovenous communication in retinitis pigmentosa with Refsum's disease-like findings

In this report we describe, herewith, a patient with primary pigmentary dystrophy of the retina (retinitis pigmentosa) associated with unilateral retinal arteriovenous communication and exudative retinal detachment. The patient had complete resolution of the retinal detachment following laser photocoagulation treatment. Such association has not been previously reported.     

Retinal thickness and visual thresholds measured in patients with retinitis pigmentosa

PURPOSE:: To determine the association between retinal thickness and visual function in patients with retinitis pigmentosa (RP). METHODS:: Retinal thickness was estimated from optical coherence tomography (OCT) images obtained for six patients with RP. The thickness measurements were compared with dark-adapted rod and minimally light-adapted cone thresholds obtained by psychophysical testing using a Tübinger perimeter and with standard light-adapted Humphrey visual field (HVF) perimetric thresholds. RESULTS:: Four patterns of association between retinal thickness and visual function were observed: normal retinal thickness and normal visual thresholds; normal retinal thickness and normal cone thresholds but elevated rod thresholds; reduced retinal thickness and elevated rod and cone thresholds; and normal retinal thickness and normal Humphrey thresholds but elevated rod and cone thresholds by Tübinger perimetry. CONCLUSION:: Retinal thinning was observed only when both rod and cone thresholds were elevated. However, normal retinal thickness was not necessarily accompanied by normal visual sensitivity. The determination of retinal thickness by OCT and its association with psychophysical measurements of visual function could be useful for identifying those RP patients who might respond most optimally to therapeutic interventions.     

Retinal detachment and retinal holes in retinitis pigmentosa sine pigmento.

Retinal detachment and retinal holes in two family members with retinitis pigmentosa sine pigmento are reported. We believe these are the first such cases reported in the literature. We describe the presenting symptoms and management, including cryotherapy, scleral buckling procedure, and sulfur hexafluoride injection (SF6), resulting in stable visual acuity in one case and retinal reattachment and improved visual acuity in the other case.     

Immunological studies in retinitis pigmentosa associated with retinal vascular leakage.

Seventeen patients with retinitis pigmentosa and vascular leakage were studied for humoral immunological abnormalities. Apart from raised levels of IgM in 5 patients no other abnormalities were found.     

Retinal S antigen reactivity in patients with retinitis pigmentosa and Usher's syndrome

Cell-mediated immunity to retinal antigens as determined by in vitro assays has been detected in a variety of retinal degenerative and retinal destructive conditions. The authors studied the in vitro reactivity to the soluble retinal S antigen of peripheral blood mononuclear cells from patients with simplex and multiplex retinitis pigmentosa (RP) and Usher's syndrome along with normal controls. The cellular stimulation index (SI) was calculated by comparing 3H-thymidine incorporation in cells exposed to either purified S antigen, crude whole human retinal antigen, or human choroidal antigen with that in unstimulated control cultures. Eight of 15 patients with RP and 5 of 6 with Usher's had a SI greater than the tolerance limits of normal values. These results indicate that the immune system may be involved either primarily or secondarily in RP.     

Retinal blood flow velocity measured by retinal function imaging in retinitis pigmentosa

Background  

To measure the retinal blood flow velocity in patients with retinitis pigmentosa using the retinal function imaging technique.     

Retinal laminar architecture in human retinitis pigmentosa caused by Rhodopsin gene mutations

PURPOSE: To determine the underlying retinal micropathology in subclasses of autosomal dominant retinitis pigmentosa (ADRP) caused by rhodopsin (RHO) mutations. METHODS: Patients with RHO-ADRP (n = 17, ages 6-73 years), representing class A (R135W and P347L) and class B (P23H, T58R, and G106R) functional phenotypes, were studied with optical coherence tomography (OCT), and colocalized visual thresholds were determined by dark- and light-adapted chromatic perimetry. Autofluorescence imaging was performed with near-infrared light. Retinal histology in hT17M-rhodopsin mice was compared with the human results. RESULTS: Class A patients had only cone-mediated vision. The outer nuclear layer (ONL) thinned with eccentricity and was not detectable within 3 to 4 mm of the fovea. Scotomatous extracentral retina showed loss of ONL, thickening of the inner retina, and demelanization of RPE. Class B patients had superior-inferior asymmetry in function and structure. The superior retina could have normal rod and cone vision, normal lamination (including ONL) and autofluorescence of the RPE melanin; laminopathy was found in the scotomas. With Fourier-domain-OCT, there was apparent inner nuclear layer (INL) thickening in regions with ONL thinning. Retinal regions without ONL had a thick hyporeflective layer that was continuous with the INL from neighboring regions with normal lamination. Transgenic mice had many of the laminar abnormalities found in patients. CONCLUSIONS: Retinal laminar abnormalities were present in both classes of RHO-ADRP and were related to the severity of colocalized vision loss. The results in human class B and the transgenic mice support the following disease sequence: ONL diminution with INL thickening; amalgamation of residual ONL with the thickened INL; and progressive retinal remodeling with eventual thinning.     

Retinal function and rhodopsin levels in autosomal dominant retinitis pigmentosa with rhodopsin mutations

We studied rod and cone function in 20 patients from six families with autosomal dominant retinitis pigmentosa, who represented five different point mutations in the gene encoding rhodopsin. In a family with a stop codon mutation at the carboxyl end of the molecule (glutamine-344), young members with the mutation were asymptomatic and clinically unaffected but showed about 1 log unit of rod sensitivity loss across the visual field and decreased rhodopsin levels; at this stage, cone function was essentially normal. In three families with mutations at the border of a transmembrane segment (arginine-135-leucine and arginine-135-tryptophan), there was neither detectable rod function nor measurable rhodopsin; cone function was variably impaired. Two families carrying different mutations (threonine-17-methionine and threonine-58-arginine) had altitudinal visual field defects with less impaired rod and cone function in the inferior than in the superior field. Rod adaptation was abnormal in both families, but the time course of adaptation differed between patients with the two mutations. Differences in the pattern of retinal dysfunction were therefore discernible in patients with different rhodopsin mutations.