Reproducibility of the Peripapillary and Retinal Perfusion Measurement with Confocal Scanning Laser Flowmetry

Kim, Dong Soo; Song, Man Sung; Choi, Kee Yong

Abstract

Confocal scanning laser flowmetry(HRF: Heidelberg Retina Flowmetry) is a new kind of instrument which enables non-invasive two-dimentional mapping of perfusion of the retina and optic disc and to evaluate the clinically available reproducibility of the peripapillary and retinal perfusion measurement with the confocal scanning laser flowmetry, the authors calculate the coefficient of variation (CV) from the parameters(volume, flow, velocity). The authors indicate two region of interest in the peripapillary region and retina, not overlapping the large vessels and measure the parameters three times consecutively(one session) while visiting three times intervalled(three session), thereafter calculate the mean CV of parameters in ten healthy eyes of ten subject. The CV of parameters obtained with the confocal scanning laser flowmetry was low relatively and therefore reproducibility was high as the CV lower, the reproducibility higher. Comparing the CV between one session and three session measurement to know the clinically available measurement frequency, the CV of three session (volume 13%, flow 16.7%, velocity 16%) was lower than the CV of one session (volume 16.7%, flow 20.7%, velocity 20.1%) in the peripapillary region(Students t test; volume p=0.009, flow p=0.03, velocity p=0.016) and the CV of three session (volume 16.7%, flow 20.7%, velocity 17%) was lower than the CV of one session (volume 18.2%, flow 21.8%, velocity 21.7%) in the retina(Students t test; volume p=0.017, flow p=0.0009, velocity p=0.0004). Above the results, the CV of parameters(13~21.8%) in one and three session had relatively high reproducibility. Also the CV between two measurements had a difference statistically but the difference was not so high, the authors concluded the confocal scanning laser flowmetry which have high resolution measure the peripapillary region and retina reproduciblly with only one time visit, three consecutive measurements.