Diffuse photoreceptor dystrophies

Objective & Hypothesis:Cone rod dystrophies (CRDs) are retinal dystrophies caused by the loss of cone receptors (congenital loss or late-onset de-generation) or abnormalities of cone pigments.

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Key Findings & Data:Mostly CRDs are non syndromic, but they can be part of several syndromes, such as the Bardet Biedl syndrome or Spinocerebellar Ataxia Type 7.

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Conclusion & Impact:Genetic counseling is recommended due to the molecular diagnosis being made.

🔬Design:Research Article

📍Scope:Comprehensive Sample

⚙️Variables:Domain Parameters

Abstract

Cone rod dystrophies (CRDs) are retinal dystrophies caused by the loss of cone receptors (congenital loss or late-onset de-generation) or abnormalities of cone pigments. Mostly CRDs are non syndromic, but they can be part of several syndromes, such as the Bardet Biedl syndrome or Spinocerebellar Ataxia Type 7. Retinitis pigmentosa (RP) is an inherited retinal dystrophy that is characterized by the progressive dysfunction of photoreceptors and pigment epithelial complex of the retina. Although RP being usually non syndromic, it can be a part of some syndromes like the Usher syndrome. RP begins with night blindness continuous with progressive loss of peripheral visual field. For both CRDs and RP, the clinical diag - nosis is based on clinical history, fundus examination and electroretinogram (ERG). Genetic counseling is recommended due to the molecular diagnosis being made. To date, there is no therapy that stops the progress of the disease. The current management includes vitamin supplementation to slow down the degenerative process, trying to treat ocular complications (cataract, macular edema) and providing psychological support to blind patients. Gene therapy, neuroprotection, retinal prosthesis are new therapeutic strategies. More research is necessary for obtaining beneficial outcomes from these new therapeutic strategies.

Özet

Kon rod distrofileri, kon reseptörlerinin kaybı (konjenital ya da gec başlangıçlı dejenerasyonu sonucu) veya kon pigmentle -rindeki anormallik sonucu oluşan retinal distrofilerdir. Kon rod distrofileri genellikle bir sendroma eşlik etmemekle beraber Bardet Biedl Sendromunun veya Spinocerebellar Ataksi Tip 7nin bir parçası olarak da karşımıza çıkabilmektedir. Retinitis Pigmentosa (RP) fotoreseptör ve retina pigment epitel kompleksinin ilerleyici kaybı ile ortaya çıkan kalıtımsal bir retinal distrofidir. RPde genellikle bir sendroma eşlik etmemekle birlikte en fazla Usher Sendromu ile birlikteliği mevcuttur. Hem kon rod distrofilerinin hem de RPnin tanısı klinik hikayeye, fundus bulgularına ve elektroretinograma (ERG) bağlı olarak konulmaktadır. Günümüzde hastalığın seyrini durduracak herhangi bir tedavi yöntemi bulunmamaktadır. Güncel tedavi dejeneratif seyri yavaşlatmak amacıyla vitamin alımını, katarakt, maküler ödem gibi göze ait sorunların tedavisini ve göremeyen hastalara psikolojik ve sosyal desteği içermektedir. Gen tedavisi, nöroproteksiyon ve retinal protezler üzerinde hala çalışılmakta olan tedavi modaliteleridir. Bunlara ait sonuçların gösterilmesi için daha fazla çalışmaya ihtiyaç vardır

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Cite This Article

BAYAR, S. A., ŞINGAR, E., YILMAZ, G. (2012). Diffuse photoreceptor dystrophies. Retina-Vitreus, Cilt: 20 - Sayı: 4, 243–249. https://ajindex.com/articles/305094

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