A fast n-dimensional nonlinear filter
In this communication, we propose an original approach for the diffusion paradigm in image processing. Our starting point is the iterative resolution of partial differentialequations (PDE) according t...
Optical coherence tomography: interpretation artifacts and new algorithm
Proc. SPIE, Vol. 5370, 2140 (2004);
doi:10.1117/12.535857
Online Publication Date: 16 June 2004
Conference Date: Monday 16 February 2004
Conference Location: San Diego, CA, USA
Conference Title: Medical Imaging 2004: Image Processing
Conference Chairs: J. Michael Fitzpatrick, Milan Sonka
Purpose:To study the frequency and severity of artifacts in opticalCoherence tomography images and to develop a new algorithm forimproved retinal thickness detection.Methods: We propose a new method tomeasure the retinal thickness in OCT scans. We compared ourmodified edge detection (MED) method to the Markov method andthe conventional OCT algorithm (cOCT) in 226 OCT macular scans.Results:We defined errors as a difference in detected interface locationof less than 100 µm offset for less than 10A-scans, otherwise it was an artifact. The frequency of errorswas reduced from 32% (cOCT) to less than 2% withthe MED method, while the Markov method had a frequencyof 5%. Artifacts were reduced from 9.3% (cOCT) to 0.9%(MED) while the Markov method had a frequency of 11.5%.Conclusion:The results show the MED method of detecting retinal thicknessis superior to the other two methods, since the OCTmethod is prone to both errors and artifacts and theMarkov method is robust only to healthy retina. Our MEDmethod is robust for detection of normal retinas and effectiveeven in eyes with pathological conditions. Use of improved retinalthickness detection algorithm should significantly improve clinical utility of theoptical coherence tomograph.