Abstract
Purpose: :
To report the confocal blue reflectance imaging as a novel noninvasive imaging modality for plotting of foveal avascular zone and to compare the effectiveness of blue reflectance imaging with fluorescein angiography.
Methods: :
In this prospective observational cross-sectional study, 40 patients (62 eyes) with diabetic maculopathy were enrolled. Patients underwent blue reflectance imaging and fundus fluorescein angiography (FA) using a confocal scanning laser ophthalmoscope (F-10; Nidek, Gamagori, Japan). For all patients, foveal avascular zone was identified in a blue reflectance image and a corresponding FA image. The foveal avascular zone boundary was manually delineated by two independent well trained observers (YU, JW). The concordance of blue reflectance and FA image of foveal avascular zone boundary was compared by size and overlapping ratio.
Results: :
The mean size of foveal avascular zone in FA image and confocal blue reflectance image was 0.346 ± 0.175 mm2 and 0.357± 0.162 mm2. The linear regression analysis showed correlation in size of foveal avascular zone between angiography and blue reflectance image (correlation coefficient =0.931, p<0.05). The overlapping ratio was 0.814 (Range 0.617 - 0.945, SD ±0.095). The reliable agreement between two image was found in size and shape.
Conclusions: :
The study of foveal avascular zone using confocal blue reflectance imaging has never been reported in the medical literature previously. Our novel method of plotting of foveal avascular zone by confocal blue reflectance imaging is simple, noninvasive and can be reliable. It has the potential to be used for detecting and quantifying the alteration of foveal avascular zone noninvasively in screening, initial evaluation, and follow up management of ischemic maculopathy.
Keywords: imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) • diabetic retinopathy