Automatic segmentation in three-dimensional analysis of fibrovascular pigmentepithelial detachment using high-definition optical coherence tomography

• Published in: British journal of ophthalmology Vol. 92; no. 2; pp. 197 - 203
• Main Authors: Ahlers, C, Simader, C, Geitzenauer, W, Stock, G, Stetson, P, Dastmalchi, S, Schmidt-Erfurth, U
• Format: Journal Article
• Language: English
• Published: BMA House, Tavistock Square, London, WC1H 9JR BMJ Publishing Group Ltd 01.02.2008; BMJ; BMJ Publishing Group LTD
• Subjects: Aged; Algorithms; Angiogenesis Inhibitors - therapeutic use; Biological and medical sciences; Choroidal Neovascularization - complications; Choroidal Neovascularization - drug therapy; Feasibility Studies; Humans; Image Interpretation, Computer-Assisted - methods; Imaging, Three-Dimensional - methods; Macular degeneration; Macular Degeneration - complications; Medical imaging; Medical sciences; Middle Aged; Miscellaneous; Morphology; Ophthalmology; Pathology; Patients; Performance evaluation; Pigment Epithelium of Eye - pathology; Product development; Quality Control; Retinal Detachment - diagnosis; Retinal Detachment - etiology; Retinal Detachment - pathology; Software; Tomography, Optical Coherence - methods; Vascular Endothelial Growth Factor A - antagonists & inhibitors; Volumetric analysis; High; Definition; Ophthalmology; Segmentation; Optical coherence tomography; Automatic analysis
• ISSN: 0007-1161; 1468-2079; 1468-2079
• DOI: 10.1136/bjo.2007.120956

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.