Abstract
Purpose:
The purpose of this study is to demonstrate visualization of abnormalities in the middle layers of the retina using en-face imaging along a contour defined using both ILM and RPE segmentations, and to show whether this method is superior to using ILM or RPE segmentations alone.
Methods:
Data from patients with cystoid macular edema and exudates were gathered from a prototype swept-source OCT system. These image volumes were processed offline with prototype ILM and RPE segmentation algorithms based on those used in the Cirrus™ HD-OCT system. En-face images were then constructed using those segmentations and also using surfaces that were fractions of the distance between the ILM and RPE.
Results:
The en-face images that followed the contours of the ILM or RPE alone often showed bands from multiple layers of the retina that obscured the visualization of mid-retinal pathology. En-face images that followed a contour that was a fraction of the distance between the ILM and RPE showed fewer such bands and therefore showed mid-retinal pathology more clearly.
Conclusions:
Neither the ILM nor the RPE follow the layers of the retina well in the mid-retinal regions where cysts and exudates are often found. Combining the two contours can reliably construct a surface that approximately follows the contours of the retina, even in highly disrupted regions where mid-retinal layers may be difficult to segment. This technique therefore gives a clear en-face image of the pathology affecting that level of the retina, and this image is often superior to that obtained by en-face imaging using either the ILM or RPE alone.
Keywords: 550 imaging/image analysis: clinical •
551 imaging/image analysis: non-clinical •
552 imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound)