Retinitis pigmentosa-associated cystoid macular oedema: pathogenesis and avenues of intervention

Abstract

Hereditary retinal diseases are now the leading cause of blindness certification in the working age population (age 16–64 years) in England and Wales, of which retinitis pigmentosa (RP) is the most common disorder. RP may be complicated by cystoid macular oedema (CMO), causing a reduction of central vision. The underlying pathogenesis of RP-associated CMO (RP-CMO) remains uncertain, however, several mechanisms have been proposed, including: (1) breakdown of the blood-retinal barrier, (2) failure (or dysfunction) of the pumping mechanism in the retinal pigment epithelial, (3) Müller cell oedema and dysfunction, (4) antiretinal antibodies and (5) vitreous traction. There are limited data on efficacy of treatments for RP-CMO. Treatments attempted to date include oral and topical carbonic anhydrase inhibitors, oral, topical, intravitreal and periocular steroids, topical non-steroidal anti-inflammatory medications, photocoagulation, vitrectomy with internal limiting membrane peel, oral lutein and intravitreal antivascular endothelial growth factor injections. This review summarises the evidence supporting these treatment modalities. Successful management of RP-CMO should aim to improve both quality and quantity of vision in the short term and may also slow central vision loss over time.

Retrospective cohort study exploring whether an association exists between spatial distribution of cystoid spaces in cystoid macular oedema secondary to retinitis pigmentosa and response to treatment with carbonic anhydrase inhibitors

“…Several case reports and small-scale studies have been published regarding the safety and efficacy of carbonic anhydrase inhibitors (CAIs) in the treatment of RP-CMO; however, to date there is currently no level 1 evidence to support this 8. In the largest retrospective study to date of CAIs involving 81 patients (157 eyes) with RP-CMO, objective improvement on OCT was observed in 53% of patients (40% of eyes) using topical dorzolamide vs 41% of patients (28% of eyes) using oral acetazolamide 10.…”

Double trouble: exudative hypertensive retinopathy in a patient with retinitis pigmentosa

“…Cystoid macular oedema (CMO) is a common occurrence in retinitis pigmentosa (RP) and may be seen in 10%–50% of these eyes 1. Various mechanisms have been proposed to account for CMO in RP which include retinal pigment epithelium (RPE) pump dysfunction, muller cell dysfunction, anti-retinal or anti-RPE antibodies and blood retinal barrier breakdown 1–3.…”

In silico analysis ofIDH3Agene revealed Novel mutations associated with Retinitis Pigmentosa

“…The IDH3A function is to catalyze the oxidative decarboxylation of isocitrate (27) which is the key rate-limiting step of the tricarboxylic acid cycle. It also plays a central role in the aerobic energy production and cellular respiration thus mutations in this gene will affect the nervous system (28, 29) and may cause cancer (30,31).Although the RP is the most common inherited disease of the retina (14, 32-36) there is still no effective therapeutic strategy and the exact pathogenesis and etiology of the disease is not clear (3,5,32,37).The aim of this study is to identify the pathogenic SNPs in the IDH3A gene and their effect on the structure and function of the protein, which might help in the overall understanding of the pathogenesis of the disease and could be used as diagnostic markers. This is the first in silico analysis in the coding region of IDH3A gene to prioritize SNPs for further genetic mapping studies.…”

“…Although the RP is the most common inherited disease of the retina (14, 32-36) there is still no effective therapeutic strategy and the exact pathogenesis and etiology of the disease is not clear (3,5,32,37).…”