Korean J Ophthalmol.  2019 Aug;33(4):359-365. 10.3341/kjo.2018.0025.

Evaluation of Foveal Avascular Zone and Capillary Plexuses in Diabetic Patients by Optical Coherence Tomography Angiography

• Ciloglu E
• Unal F
• Sukgen EA
• Koçluk Y

• KMID: 2454777
• DOI: http://doi.org/10.3341/kjo.2018.0025

Abstract

PURPOSE
To investigate the foveal avascular zone (AVZ), superficial and deep foveal and parafoveal vessel density (VD) changes related to diabetic retinopathy.
METHODS
Forty-nine type 2 diabetes mellitus (DM) and 45 healthy control subjects were included in this study. The demographic data (age and sex), disease duration, and level of glycated hemoglobin were collected. Superficial VD (%), superficial AVZ area (mm2), deep VD (%) and deep AVZ area (mm2) were evaluated via optic coherence tomography angiography.
RESULTS
Superficial AVZ was 0.438 ± 0.05 mm2 in the DM group, 0.246 ± 0.022 mm2 in the control group (p < 0.001). Deep AVZ was 0.732 ± 0.06 mm2 in the DM group, and 0.342 ± 0.022 mm2 in the control group (p < 0.001). Superficial foveal VD was 29.45 ± 0.76 mm2 in the DM group, and 34.86 ± 0.75 mm2 in the control group (p < 0.001). Deep foveal VD was 24.85 ± 1.08 mm2 in the DM group, and 33.47 ± 0.56 mm2 in the control group (p < 0.001).
CONCLUSIONS
In this study, we demonstrated an enlargement in the foveal AVZ along with a reduction in the vascular density of the superficial and deep capillary network in the foveal and parafoveal area using optic coherence tomography angiography in patients with nonproliferative diabetic retinopathy. This technique can be used to monitor the progression of the disease and to evaluate the response to treatment.

Keyword

Capillary plexus; Diabetic retinopathy; Foveal avascular zone; Ischemia; Optic coherence tomography angiography

MeSH Terms

Angiography*
Capillaries*
Diabetes Mellitus, Type 2
Diabetic Retinopathy
Hemoglobin A, Glycosylated
Humans
Ischemia
Tomography, Optical Coherence*

Figure

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  Fig. 1 Macular perfusion parameters of a 3 × 3 mm2 angiography scan size using optical coherence tomography angiography. The foveal avascular zone is automatically delineated by the software and represented by the color yellow.

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  Fig. 2 Images of the macular region and the sections where vessel densities are calculated.

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