Choroidal neovascularization imaging using multiple en face optical coherence tomography angiography image averaging.
Graefes Arch Clin Exp Ophthalmol
; 257(6): 1119-1125, 2019 Jun.
Article
in En
| MEDLINE
| ID: mdl-30783783
ABSTRACT
PURPOSE:
To determine the effects of averaging five en face optical coherence tomography angiographic (OCTA) images on the quality of the images in eyes with a choroidal neovascularization (CNV).METHODS:
Twenty-seven eyes of 25 patients (18 men, 7 women; average age 71.0 years) with a CNV were examined by OCTA (OCT HS-100, Canon. Japan). A 3 × 3-mm image including the CNV was recorded and automatically segmented between the retinal outer layers. Analyses were performed on a single image (S-image) and the average of five single images of the same area (A-images). The region of the CNV was selected by ImageJ, and the peak signal-to-noise ratio (PSNR), the vascular density (VD), fractal dimension (FD), and the noise component using band pass filter (BPF) processing of the S- and A-images of each case were compared.RESULTS:
The average PSNR for the A-images was 14.0 which was significantly higher than the 12.2 for the S-images (P < 0.01). However, the average VD was 33.6% for the S-images and 34.8% for the A-images (P > 0.1). The average FD was 1.67 for the S-images and 1.54 for the A-images (P < 0.01). The mean luminance difference obtained by subtracting the luminance of the A-image from the S-image after BPF processing was 10.41 ± 14.66 db which was positive for all eyes.CONCLUSIONS:
The better quality of the A-images of a CNV and absence of a significant difference in the vascular density indicates that the improvement was due to the removal of the same signal levels of the noise component and blood vessels.Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Retinal Vessels
/
Fluorescein Angiography
/
Choroid
/
Choroidal Neovascularization
/
Tomography, Optical Coherence
Type of study:
Observational_studies
/
Prognostic_studies
Limits:
Aged
/
Female
/
Humans
/
Male
Language:
En
Journal:
Graefes Arch Clin Exp Ophthalmol
Year:
2019
Document type:
Article
Affiliation country:
Japan