J Korean Ophthalmol Soc.  2017 Sep;58(9):1058-1065. 10.3341/jkos.2017.58.9.1058.

Analysis of Foveal Microvascular Structures Using Optical Coherence Tomography Angiography in Age-stratified Healthy Koreans

• Noh D
• Ryu G
• Sagong M

• KMID: 2390069
• DOI: http://doi.org/10.3341/jkos.2017.58.9.1058

Abstract

PURPOSE
To evaluate foveal avascular zone (FAZ) microvascular structural changes in healthy Korean subjects stratified by age using optical coherence tomography angiography (OCTA).
METHODS
Eighty eyes of 43 healthy volunteer subjects who had 20/20 or better best corrected visual acuity without other ocular or systemic disease except vitreous floaters and dry eye syndrome were enrolled and stratified by age group. To measure FAZ size and vascular density (VD) of the superficial capillary plexus (SCP) and deep capillary plexus (DCP), OCTA (DRI OCT Triton, Swept Source OCT, Topcon, Tokyo, Japan) scans were performed over fovea-centered 3 × 3 mm² regions, and then compared with central macular thickness (CMT) and subfoveal choroidal thickness.
RESULTS
Mean age of the participants was 46.4 ± 16.1 (20-78). The SCP and DCP FAZ sizes were 0.32 ± 0.11 mm² and 0.41 ± 0.14 mm², respectively. There was a significant difference by age group (p < 0.001, p < 0.001), respectively. The FAZ VD for SCP and DCP was 28.96 ± 3.05% and 33.15 ± 3.64%, respectively. There was no difference between age groups (p = 0.118, p = 0.637). Univariate and multiple linear regression analysis showed that the FAZ size of SCP and DCP was significantly correlated with age (p = 0.039, p = 0.002) and CMT (p = 0.007, p = 0.013), respectively. The SCP and DCP FAZ size were positively correlated with age (R² = 0.279, p < 0.001, R² = 0.344, p < 0.001), and negatively correlated with CMT (R2 = 0.354, p < 0.001, R2 = 0.285, p < 0.001), respectively.
CONCLUSIONS
The FAZ size of SCP and DCP increased with age and were negatively correlated with CMT. These results suggest that consideration of age and CMT is important when performing the clinical evaluation of FAZ size in healthy subjects.

Keyword

Age; Foveal avascular zone; Healthy subjects; Optical coherence tomography angiography; Vascular density

MeSH Terms

Angiography*
Capillaries
Choroid
Dry Eye Syndromes
Healthy Volunteers
Humans
Linear Models
Neptune
Tomography, Optical Coherence*
Visual Acuity

Figure

• 

  Figure 1 Manual outlining (green) of the border of foveal avascular zone. Optical coherence tomography angiography 3 × 3 mm scans segmented at the superficial capillary plexus (A) and the deep capillary plexus (B).

• 

  Figure 2 Variation of foveal avascular zone (FAZ) area with age and central macular thickness (CMT). Area of superficial capillary plexus (SCP) FAZ (A) showed significant positive correlation with age, while CMT (B) was negatively correlated (R2 = 0.279, p < 0.001, R2 = 0.354, p < 0.001). Also, the area of deep capillary plexus (DCP) FAZ (C) showed positive correlation with age, while CMT (D) was negatively correlated (R2 = 0.344, p < 0.001, R2 = 0.285, p < 0.001).

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