Steerable OCT catheter for real-time assistance during teleoperated endoscopic treatment of colorectal cancer

Abstract

When detected early, colorectal cancer can be treated with minimally invasive flexible endoscopy. However, since only specialized experts can delineate margins and perform endoscopic resections of lesions, patients still often undergo colon resections. To better assist in the performance of surgical tasks, a robotized flexible interventional endoscope was previously developed, having two additional side channels for surgical instrument. We propose to enhance the imaging capabilities of this device by combining it with optical coherence tomography (OCT). For this purpose, we have developed a new steerable OCT instrument with an outer diameter of 3.5 mm. The steerable instrument is terminated with a 2 cm long transparent sheath to allow three-dimensional OCT imaging using a side-focusing optical probe with two external scanning actuators. The instrument is connected to an OCT imaging system built around the OCT Axsun engine, with a 1310 nm center wavelength swept source laser and 100 kHz A-line rate. Once inserted in one of the side channels of the robotized endoscope, bending, rotation and translation of the steerable OCT instrument can be controlled by a physician using a joystick. Ex vivo and in vivo tests show that the novel, steerable and teleoperated OCT device enhances dexterity, allowing for inspection of the surgical field without the need for changing the position of the main endoscope.

Diagnosing colorectal abnormalities using scattering coefficient maps acquired from optical coherence tomography

“…Mora et al developed a steerable OCT catheter for real‐time assistance during teleoperated endoscopic treatment of colorectal cancer. [ 50 ] The catheter was steerable which could be used for enhancing the performance of the robotically controlled flexible colonoscope. This study demonstrated their work using swine in vivo images.…”

Data Stream Stabilization for Optical Coherence Tomography Volumetric Scanning

“…To compare the conventional pullback and robotic 3D scanning performance we use an OCT instrument with an outer diameter of 3.5 mm [47]. The instrument is terminated at the distal end with a transparent sheath on the tip, which allows three-dimensional OCT imaging using an internal rotating side-focusing optical probe with two proximal external scanning actuators.…”

“…We have previously investigated the NURD performance of an OCT catheter that was developed by our team for realtime assistance during minimally invasive robotized treatment of colorectal cancer [47]. This robotized OCT catheter can be inserted in one of the two instrument channels of the robotized interventional endoscope and teleoperated using a master controller.…”

Image-Guided Control of an Endoscopic Robot for OCT Path Scanning

“…In [2], a custom-made OCT probe is integrated with a continuum robot to achieve micro and macro scale motion. New systems are also currently under development for assistance to surgical procedures performed with robotic flexible endoscopes in the digestive tube [3]. In such systems, the OCT probe is rather used to analyze specific areas online.…”

“…A motorized OCT probe [3] is inserted in the bending instrument shaft and extends 25 mm out its distal tip. The probe consists of an external motor, an optical fiber, ball lens, a casing, and the associated electronic and optical elements.…”