Abstract
Purpose::
To evaluate differences in number and gravity of artefacts produced by two scan protocols using Stratus OCT:Fast Macular Thickness Map and Macular Thickness Map.
Methods::
A prospective,observational case series study was developed in order to investigate the topic.A population of 43 outpatients was enrolled.Every patient underwent Stratus OCT examination(Carl Zeiss Meditech,Dublin,California)using both FMTM and MTM.Only one eye of each patient was used randomizing with a coin.With these scan modes, six radial scans were obtained.Each radial scan was manually analyzed by expert operators in order to determine the presence of artefacts in detection of inner and outer limit of retina, using Retinal Thickness (single eye) analysis method.A score of gravity was given considering distance from the fovea (1=located in the outer ring area of the map,from 3 to 4.5 mm to the centre;2=located in the middle ring area,from 1.5 to 3 mm to the centre;3=located in the inner ring area,3 mm of diameter).Conditional logistic regression,adjusted for clustering according to individuals,was used to evaluate a discordance in the probability of having artefacts of the two methods.To evaluate seriousness of the artefacts simple regression was used.
Results::
43 eyes were enrolled in the study.Mean age was 66.9±1.6.The odds ratio of having an artefact using the fast method compared to the normal method is 1.83 (p=0.06; CI: 0.97-3.46).No relation has been shown according to the gravity of the artefacts.
Conclusions::
According to the results no differences have been shown beetwen the two methods.Anyway other studies are necessary to better evaluate errors produced by OCT analysis on retinal thickness measurement. In particular,it would be interesting to investigate if the number of artefacts could change in different pathologies affecting retina.
Keywords: imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) • retina • clinical (human) or epidemiologic studies: systems/equipment/techniques