Diagnostic Fiber-based Optical Imaging Catheters

Fiber optics miniaturization and advances in signal acquisition and processing have allowed the development of fiber-based optical imaging catheters that permit instantaneous luminal organ imaging. This technique is applicable in clinical settings for diagnosing various diseases. Intravascular optical coherence tomography (IV-OCT), a catheter-based optical imaging technique, acquires high-resolution cross-sectional human coronary arterial wall imaging, enabling precise assessment of coronary atherosclerosis. OCT with a balloon-centering catheter or a tethered capsule acquires comprehensive three-dimensional images of the distal esophagus for diagnostic imaging in patients with esophageal diseases, including Barrett's esophagus. Spectrally encoded confocal microscopy (SECM), an advanced type of confocal microscopy that uses diffraction grating and a broadband laser source to laterally scan the sample without mechanical motion, has been developed as a tethered confocal endomicroscopy capsule to diagnose and monitor eosinophilic esophagitis, an allergic condition in the esophageal wall. In this review, the authors describe the recent development of fiber-based imaging catheters with rotary scanning for diagnosing various diseases in luminal organs, including the coronary artery and esophagus. Further developments, including miniaturization of optics, increased speed, and multimodal acquisition, could significantly improve diagnostic capability to improve patient care.