Novel optical coherence tomography approaches for high-resolution biomedical imaging (Orale)
Résumé
Optical coherence tomography (OCT) is an established technique for cross-sectional imaging of biological tissues with micrometer-scale spatial resolution [1]. Commercially available OCT systems are employed in diverse medical applications, notably in ophthalmology. OCT has also begun to be used in interventional cardiology and has shown promise in dermatology to improve the diagnostic process.
Imaging at high spatial resolution with OCT is of particular interest to resolve subtle morphological changes of tissues for early diagnosis of diseases including skin cancers. Since the introduction of OCT, significant progress in the spatial resolution of OCT images has been achieved.
Two novel approaches of OCT for high spatial resolution imaging in dermatology will be presented in this talk: Full-Field Optical Coherence Microscopy (FF-OCM) and Line-field Confocal Optical Coherence Tomography (LC-OCT).
FF-OCM is based on low-coherence interference microscopy, using full-field illumination with a low-coherence light source (a broadband light-emitting diode - LED) and detection with an area camera to acquire en face tomographic images [2]. FF-OCM benefits from the transverse imaging resolution of optical microscopy (∼ 1.0 µm) along with the capacity of optical axial sectioning at micrometer-scale resolution [3].
LC-OCT was introduced recently for high-resolution B-scan imaging in real-time. The technique is based on line illumination and detection using broadband spatially coherent light (generated by a supercontinnum laser) and a line-scan camera in a two-beam interference microscope. Isotropic spatial resolution of ∼ 1.0 µm (transverse × axial) is achieved. In vivo cellular-level resolution imaging of human skin is demonstrated at 15 frames/s with a penetration depth of ∼ 500 µm