Validation of Compensation Algorithm in Healthy Volunteers Using Spectral Domain Optical Coherence Tomography...

Area of Science:

• Ophthalmology
• Medical Imaging
• Optical Coherence Tomography

Background:

• Choriocapillaris (CC) imaging using spectral domain optical coherence tomography angiography (SD-OCTA) can be affected by signal attenuation.
• Accurate quantification of CC flow deficits (CC FD %) is crucial for diagnosing and monitoring various ocular diseases.

Purpose of the Study:

• To develop and validate a device-specific algorithm for SD-OCTA to correct signal attenuation in CC en face OCTA slabs.
• To assess the impact of this compensation algorithm on CC FD % measurements in healthy subjects.

Main Methods:

• A 6x6 mm pattern was used to image healthy subjects with SD-OCTA.
• CC slabs were segmented and normalized; CC FD % was computed before and after applying the SD-OCTA specific compensation algorithm.
• The performance of the SD-OCTA algorithm was compared to a previously developed SS-OCTA compensation algorithm.

Main Results:

• The SD-OCTA specific algorithm showed no statistically significant difference in CC FD % between compensated and uncompensated images (p=0.1).
• Compensated and uncompensated CC FD measurements were strongly correlated (p<0.001), with good agreement shown by Bland-Altman plots.
• Applying an SS-OCTA algorithm to SD-OCTA data resulted in a statistically significant difference in CC FD % (p<0.0001).

Conclusions:

• A device-specific compensation algorithm for SD-OCTA can be applied to CC en face slabs without introducing artifactual flow deficits.
• The validated algorithm yields similar CC FD % values in compensated and uncompensated images of healthy eyes.
• This algorithm is crucial for accurate CC analysis in SD-OCTA imaging.