Automatic segmentation in three-dimensional analysis of fibrovascular pigmentepithelial detachment using high-definition optical coherence tomography. Issue 2 (26th October 2007)

• Record Type: Journal Article
• Authors: Ahlers, C; Simader, C; Geitzenauer, W; Stock, G; Stetson, P; Dastmalchi, S; Schmidt-Erfurth, U
• Is Part Of: British journal of ophthalmology. Volume 92:Issue 2(2008)
• Page Start: 197
• Page End: 203
• Publication Date: 2007-10-26
• Subjects: Ophthalmology -- Periodicals; 617.7
• DOI: 10.1136/bjo.2007.120956
• Languages: English
• ISSNs: 0007-1161

Abstract

Abstract : Background/aims: A limited number of scans compromise conventional optical coherence tomography (OCT) to track chorioretinal disease in its full extension. Failures in edge-detection algorithms falsify the results of retinal mapping even further. High-definition-OCT (HD-OCT) is based on raster scanning and was used to visualise the localisation and volume of intra- and sub-pigment-epithelial (RPE) changes in fibrovascular pigment epithelial detachments (fPED). Two different scanning patterns were evaluated. Methods: 22 eyes with fPED were imaged using a frequency-domain, high-speed prototype of the Cirrus™ HD-OCT. The axial resolution was 6 μm, and the scanning speed was 25 kA scans/s. Two different scanning patterns covering an area of 6×6 mm in the macular retina were compared. Three-dimensional topographic reconstructions and volume calculations were performed using MATLAB™-based automatic segmentation software. Results: Detailed information about layer-specific distribution of fluid accumulation and volumetric measurements can be obtained for retinal- and sub-RPE volumes. Both raster scans show a high correlation (p<0.01; R2 >0.89) of measured values, that is PED volume/area, retinal volume and mean retinal thickness. Quality control of the automatic segmentation revealed reasonable results in over 90% of the examinations. Conclusion: Automatic segmentation allows for detailed quantitative and topographic analysis of the RPE and the overlying retina. In fPED, the 128×512 scanning-pattern shows mild advantages when compared with the 256×256 scan. Together with the ability for automatic segmentation, HD-OCT clearly improves the clinical monitoring of chorioretinal disease by adding relevant new parameters. HD-OCT is likely capable of enhancing the understanding of pathophysiology and benefits of treatment for current anti-CNV strategies in future.