Foveal ganglion cell layer damage in ischemic diabetic maculopathy: correlation of optical coherence tomographic and anatomic changes.
OBJECTIVE
To describe the morphologic features of ischemic diabetic maculopathy by high-resolution optical coherence tomography (OCT) and their correlation with the damaged foveal avascular zone (FAZ) on fluorescein angiography (FA).


METHODS
Observational case series.


METHODS
One hundred twenty-four eyes of 63 patients with diabetic retinopathy and acceptable FA and OCT images were studied. Twenty-three normal fellow eyes of 23 nondiabetic patients with unilateral acute central serous choroidopathy also were studied.


METHODS
High-speed Fourier-domain OCT was used with a speckle noise-reduction technique to obtain detailed horizontal and vertical images through the center of the fovea and horizontal raster scans every 100 microm. Foveal ganglion cell layer (GCL) damage was identified on OCT as an evident difference in foveal thickness and contour compared with a normal fovea or as asymmetry within the fovea. Fluorescein angiography was performed by confocal scanning laser ophthalmoscope (HRA 2; Heidelberg Engineering, Heidelberg, Germany), and FAZ damage visible during the FA arterial phase was graded according to the Early Treatment Diabetic Retinopathy Study (ETDRS) FA grading system. Correlations were sought between foveal GCL damage identified on OCT and FA capillary dropout sites.


METHODS
Foveal GCL damage on OCT, the size of the foveola on OCT (defined as the area of GCL thickness <10 microm), ETDRS grading of FAZ on FA, and visual acuity.


RESULTS
Among the 124 eyes with diabetic retinopathy, 62 (50%) had FA evidence of either FAZ damage higher than grade 1 or FAZ capillary loss. In these eyes, damage to the FAZ seen on FA also could be detected on OCT (positive predictive value, 84.5%; negative predictive value, 72.9%), and locations of FAZ damage seen on FA corresponded well with sites of foveal GCL damage on OCT. In nondiabetic, normal eyes, the size of the foveola on OCT matched the size of the FAZ on FA.


CONCLUSIONS
Evidence of foveal GCL damage on OCT is a good indicator of macular ischemic damage in eyes with diabetic retinopathy. Although in this study FA was more sensitive than OCT in detecting vascular damage, OCT provides objective results and seems to be a good noninvasive substitute for FA.
Byeon
Suk Ho
SH
The Institute of Vision Research, Department of Ophthalmology, Yonsei University College of Medicine, Seodaemun-Gu, Seoul, Korea. shbyeon@yuhs.ac.kr
Chu
Young Kwang
YK
Lee
Hun
H
Lee
Sang Yeop
SY
Kwon
Oh Woong
OW
D000368:Aged; D003922:Diabetes Mellitus, Type 1 / Q000150:complications; D003924:Diabetes Mellitus, Type 2 / Q000150:complications; D003930:Diabetic Retinopathy / Q000175:diagnosis*; D005260:Female; D005451:Fluorescein Angiography; D005583:Fourier Analysis; D005584:Fovea Centralis / Q000473:pathology*; D006801:Humans; D007511:Ischemia / Q000175:diagnosis*; D008297:Male; D008875:Middle Aged; D012165:Retinal Ganglion Cells / Q000473:pathology*; D012171:Retinal Vessels / Q000473:pathology*; D041623:Tomography, Optical Coherence; D014792:Visual Acuity