Hessian analysis for the delineation of amorphous anomalies in optical coherence tomography images of the aortic wall

Eusebio Real; José Fernando Val-Bernal; José M Revuelta; Alejandro Pontón; Marta Calvo Díez; Marta Mayorga; José M López-Higuera; Olga M Conde

doi:10.1364/BOE.7.001415

Hessian analysis for the delineation of amorphous anomalies in optical coherence tomography images of the aortic wall

Biomed Opt Express. 2016 Mar 21;7(4):1415-29. doi: 10.1364/BOE.7.001415. eCollection 2016 Apr 1.

Authors

Eusebio Real¹, José Fernando Val-Bernal², José M Revuelta³, Alejandro Pontón⁴, Marta Calvo Díez⁴, Marta Mayorga², José M López-Higuera¹, Olga M Conde¹

Affiliations

¹ Photonics Engineering Group (GIF), Department TEISA, University of Cantabria, Plaza de la Ciencia S/N, 39005 Santander, Spain.
² IDIVAL and Anatomical Pathology Department, Marqués de Valdecilla University Hospital, Medical Faculty, University of Cantabria, Avda, Cardenal Herrera Oria S/N 39011, Santander, Spain.
³ Medical and Surgical Sciences Department, Faculty of Medicine, University of Cantabria, Avda, Cardenal Herrera Oria S/N 39011, Santander, Spain.
⁴ Cardiovascular Surgery Service, Marqués de Valdecilla University Hospital, Avenida Valdecilla S/N, 39008 Santander, Spain.

Abstract

The aortic aneurysm is a disease originated mainly in the media layer of the aortic wall due to the occurrence of degraded areas of altered biological composition. These anomalous regions affect the structure and strength of the aorta artery, being their occurrence and extension proportional to the arterial vessel health. Optical Coherence Tomography (OCT) is applied to obtain cross-sectional images of the artery wall. The backscattering mechanisms in tissue make aorta images difficult to analyze due to noise and strong attenuation with penetration. The morphology of anomalies in pathological specimens is also diverse with amorphous shapes and varied dimensions, being these factors strongly related with tissue degradation and the aorta physiological condition. Hessian analysis of OCT images from aortic walls is used to assess the accurate delineation of these anomalous regions. A specific metric of the Hessian determinant is used to delineate degraded regions under blurry conditions and noise. A multiscale approach, based on an anisotropic Gaussian kernel filter, is applied to highlight and aggregate all the heterogeneity present in the aortic wall. An accuracy estimator metric has been implemented to evaluate and optimize the delineation process avoiding subjectivity. Finally, a degradation quantification score has been developed to assess aorta wall condition by OCT with validation against common histology.

Keywords: (100.3008) Image recognition, algorithms and filters; (110.4500) Optical coherence tomography; (170.3880) Medical and biological imaging; (170.4580) Optical diagnostics for medicine; (170.6935) Tissue characterization.