Vascular maturity of type 1 and type 2 choroidal neovascularization evaluated by optical coherence tomography angiography

Vessel maturation is considered to proceed by pruning branches resulting in less branching vessels. This study investigated the vessel junction densities of type 1 and type 2 choroidal neovascularizations (CNVs) using optical coherence tomography angiography (OCTA). We collected consecutive data from treatment-naïve eyes diagnosed with typical age-related macular degeneration (AMD). The OCTA images with CNV were analyzed to calculate vessel areas, vessel lengths, and vessel junction densities. Of 60 eyes in 60 patients, type 1 CNV diagnoses had been made in 40 eyes, and type 2 CNV in 20 eyes. We found no significant difference in vessel areas between type 1 CNV and type 2 CNV (type 1 CNV, 0.44 ± 0.37 mm2; type 2 CNV, 0.37 ± 0.48 mm2), and no significant difference in vessel lengths (type 1 CNV, 18.24 ± 15.96 mm; type 2 CNV, 16.13 ± 21.45 mm). However, the vessel junction density of type 1 CNV was significantly lower than that of type 2 CNV by 16.0% (P = 0.008). OCTA revealed that the vessel junction densities of type 1 CNVs were lower than those of type 2 CNVs, suggesting type 1 CNV vessels are more mature than type 2 CNV vessels.