Optical coherence tomography fast versus regular macular thickness mapping in diabetic retinopathy

Objective: The purpose of the study was to investigate if absolute
values and reproducibility of thickness maps obtained from 2
optical coherence tomography (OCT) scanning protocols, regular
high-resolution and fast low-density mode, differ in patients with
diabetic macular edema. Methods: A total of 26 consecutive patients
undergoing fluorescein angiography and Stratus OCT scanning for the
evaluation of diabetic macular edema at the Departments of
Ophthalmology in Munich and Vienna were included. Results: Retinal
thickness of the central field of the thickness map measured by
fast retinal thickness protocol was 287 +/- 97 and 290 +/- 113 mu m
by the regular protocol. This difference as well as that for all
other fields was not statistically significant. Three times
repeated measurements applying both OCT scanning modes in 10
patients yielded very good intrasession correlation coefficients
between 0.70 and 0.99, with corresponding intrasession standard
deviations ranging between 6 and 16 mu m. The fast mode yielded
slightly less reproducible values than the regular mode. Visual
acuity did not influence the results. Conclusion: In practice both
scanning modes caninterchanged and absolute values can be compared
directly. Best reproducibility is obtained with higher sampling
density even in patients with reduced visual acuity due to diabetic
macular edema. Copyright (C) 2008 S. Karger AG, Basel.