Ocular pulse amplitude is reduced in patients with advanced retinitis pigmentosa

Abstract

Background/aims-The choroid, a low resistance vascular structure carrying 85% of the ocular blood flow, provides nourishment to and removal of potential toxic waste products from the adjacent non-vascularised outer layers of the retina, macula, and optic disc regions. Choroidal perfusion may be reduced in retinitis pigmentosa (RP) and might contribute to retinal pigment epithelium (RPE) degeneration. The aim of this study was to determine whether choroidal perfusion is reduced in RP and whether this is correlated with the stage of disease. Conclusions-OPA can be used neither for early clinical detection of RP nor to follow the natural course of the disease. However, our data show that in advanced stages of RP not only the retina but also the choroidal circulation is aVected. (Br J Ophthalmol 2001;85:678-682) Retinitis pigmentosa (RP) comprises a group of progressive degenerative retinal diseases caused by genetic defects localised on diVerent chromosomes aVecting approximately 1.5 million people worldwide. In the majority of cases, RP leads to blindness at around the age of 60 years. Methods-Ocular

Physiological diurnal variability and characteristics of the ocular pulse amplitude (OPA) with the dynamic contour tonometer (DCT-Pascal®)

“…Both the mean value of the ocular pulse amplitude (2.2 ± 0.6 mmHg) and its range (1-3.4 mmHg) were in agreement with those previously reported [2,10,11].…”

Retinal vessel oxygen saturation and vessel diameter in retinitis pigmentosa at various ages

“…This increased tissue oxygen level causes a reduction in oxygen intake from retinal circulation, resulting in the lower AVS. However, choroidal blood flow was also found to be reduced in RP [42][43][44][45], which may partially counteract the effects of oxygen diffusion from the choroid.…”

ET-1 plasma levels, choroidal thickness and multifocal electroretinogram in retinitis pigmentosa

“…Several previous hemodynamic studies showed a reduction in both choroidal blood flow and retinal blood flow in RP, by using color Doppler imaging and laser Doppler flowmetry (Langham and Kramer, 1990;Akyol et al, 1995;Cellini et al, 1997;Schmidt et al, 2001;Falsini et al, 2011;Grunwald et al, 1996) and in addition, other authors found a positive correlation between increased ET-1 plasma concentration and abnormalities in the microcirculation not only in the eye, but also in the whole body (Cellini et al, 2010;Konieczka et al, 2012). Notably we reported a negative association between choroidal thickness and ET-1 (r = − 0.702; p b 0.023) and hypothesize that the reduction of choroidal thickness may be determined by the vasoconstrictor effect of ET-1 which could cause choroidal vascular abnormalities and blood flow impairment with a resulting relative ischemia leading to worsening of the abiotrophic process of the macular photoreceptors.…”