This paper discusses an availability of proposed Non-Contact Phase Difference type Imager capable of detecting a lung tumor based on phase differential technique for Video-Assisted Thoracic Surgery called VATS. The developed sensor is composed of an air supply system and an optical fiber distance sensor next to the air nozzle. A removed human lung is used to verify the performance of the developed sensor. Toward clinical application, it is confirmed that both a tumor detection capability and a safety to the lung tissues of the developed sensor through in vivo experiments by using pig lungs. Finally, we also show a newly sensing system for clinical application.
Currently, MRI is used not only for diagnosis but also for intraoperative surgical treatment. The surgeon determines the position of the disease region by comparing the MRI image and the patient's condition during the operation. Therefore, the predicted spatial position of the diseased part is based mainly on the surgeon's knowledge and experience, and surgeons do not fully utilize the information obtained from the MRI image. We have developed a prototype of a slice image overlay system, comprising an MRI-compatible display for open-type MRI systems and image registration and visualization software to acquire appropriate MRI slice images that are precisely correlated to the position of an MRI gantry. In this paper, we present the design of a fully MRI-compatible display device consisting of an optical fiber bundle, a lens system, and a half mirror, as well as the registration method used. We have achieved an image resolution of 1.0 mm/pixel. Phantom experiments have been performed to evaluate the MRI compatibility and image overlay accuracy of the device. Use of this device in the MRI gantry resulted in an S/N decay of 0.7% in the image and a target registration error of less than 1.2 ± 0.5 mm around the center of the display. It has been shown that the proposed system has adequate MRI compatibility and can function as a new vision system for open-type MRI systems and assist surgeons in minimally invasive surgeries.
Arrhythmia surgery is performed to treat serious arrhythmia such as atrial fibrillation and ventricular tachycardia unable to be treated by catheter ablation. Mapping devices are needed to find electrical abnormal regions. Open heart surgery is invasive for patient's body. Recently, endoscopic arrhythmia surgery is reported as minimally invasive surgery. Existing mapping device can be used only in open heart surgery. There is no mapping device available under endoscopic surgery. We developed a local multi-electrode array to measure epicardial electrophysiological data under endoscopic surgery. However, it can obtain the propagation only in the local area not in the global area. We recorded single beat electrical activities at different time and different location and mapped them onto a three-dimensional heart model. The phase shifts in local potentials were synchronized in reference to the ECG. Location errors due to heart beat and deformation were corrected by a propagation registration method assuming the continuous propagation in the heart. Both registration errors and the distribution of propagation decreased in simulation data. Continuous propagation was obtained in experimental data. Global propagation of excitation can be obtained from local isopotential maps.