Reliability of retinal vessel calibre measurements using a retinal oximeter

[摘要] BackgroundSummarised retinal vessel diameters are linked to systemic vascular pathology. Monochromatic images provide best contrast to measure vessel calibres. However, when obtaining images with a dual wavelength oximeter the red-free image can be extracted as the green channel information only which in turn will reduce the number of photographs taken at a given time. This will reduce patient exposure to the camera flash and could provide sufficient quality images to reliably measure vessel calibres.MethodsWe obtained retinal images of one eye of 45 healthy participants. Central retinal arteriolar and central retinal venular equivalents (CRAE and CRVE, respectively) were measured using semi-automated software from two monochromatic images: one taken with a red-free filter and one extracted from the green channel of a dual wavelength oximetry image.ResultsParticipants were aged between 21 and 62 years, all were normotensive (SBP: 115 (12) mmHg; DBP: 72 (10) mmHg) and had normal intra-ocular pressures (12 (3) mmHg). Bland-Altman analysis revealed good agreement of CRAE and CRVE as obtained from both images (mean bias CRAE = 0.88; CRVE = 2.82).ConclusionsSummarised retinal vessel calibre measurements obtained from oximetry images are in good agreement to those obtained using red-free photographs.

[发布日期] 2015-12-24

[关键词] Optic Nerve Head;Retinal Vessel;South Asian;Monochromatic Image;Vessel Calibre