| Foveal
ganglion cell layer damage in ischemic diabetic maculopathy: correlation
of optical coherence tomographic and anatomic changes.Ophthalmology.
2009 Oct;116(10):1949-59.e8. Epub 2009 Aug 21.
PURPOSE: 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). DESIGN: Observational case series. PARTICIPANTS: 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 obtaindetailed 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. MAIN OUTCOME MEASURES: 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. |