This paper explains about endoscopic surgery simulation based on medical image processing. Due to the progress of medical imaging devices, it is possible to acquire very precise volumetric images of a patient. These precise volumetric images enable us to simulate endoscopic surgery. This paper classifies types of surgical simulation into three categories:(a) simulation based on simple visualization, (b) deformation simulation of single organ, and (c) integrated simulation of endoscopic surgery. Here, we show examples of surgical simulation including virtualized endoscopy system, TBLB path simulation, virtual unfolded view generation of the stomach, and virtual laparoscopic image generation. Several simulation images are also presented here.

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This paper reviews precise, dissectable, and inanimate patient models (simulators) for surgical skill training, mainly in minimally invasive surgery. Currently, such models have been developed for thoracoscopic surgery, endoscopic sinus surgery (ESS), arthroscopy, laparoscopy, temporal bone surgery, neurovascular intervention, and even for off-pump coronary artery bypass grafting on a beating heart. Many of them extract precise shape data from actual patient CT/MRI images and fabricate a tangible object utilizing rapid prototyping or three-dimensional printing technology with carefully chosen materials that give haptic feedback similar to live tissues in resection. Sharing many underlying technologies, such patient models surpass virtual reality simulators in reality of “look and feel” in operation, cost performance, and acceptance of wide variety of clinical instruments. A training system using real patient models for ESS that enables self-learning and remote teaching using a metaphor of a mirror is also introduced.

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3D medical images reconstructed from MRI or CT images are currently used in various applications for diagnosis and for treatment. The application of medical virtual reality techniques to 3D images has a large potential to provide future medical treatments through telemedicine. Surgery simulation is one of the main applications of medical virtual reality. A surgery simulation system focuses on the requirements of reality, real-time visual and haptic feedbacks, quantitative deformation, representation of a tissue's internal structures such as blood vessels, and on the various forms of manipulation. By using such a simulation system, surgeons are able to trial various approaches to an operation and so carefully plan procedures before the actual surgery. This paper introduced a surgery simulation system using a patient-specific model that takes our research as an example, especially a system for laparotomy and laparoscopic surgery, a tele-surgery simulation system and surgery simulation for robotic surgery training.

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In the endoscopic surgical fields, much information which could be used intraoperatively is strongly demanded. We formulated a new magneto-optic hybrid 3D sensor configuration, and have developed an augmented reality navigationsystem using the accurate three dimensional sensor system that can be utilized in the endoscopic surgeries. This systemmeasures the 3D position of the tip of ultrasound probe in the abdominal cavity using magnetic 3D position tracker. Accuracyof the magnetic tracker is affected by metallic objects such as surgical tools that distort the magnetic field. We proposereal-time distortion correction of the magnetic fields using a magneto-optic hybrid 3D position tracker aiming to acquire theaccurate 3D ultrasound image. In this paper, we evaluated the effectiveness of the navigation system especially that of ourmethod of rapid distortion correction of magnetic fields in the operative environment. The error caused by magneticdistortion was reduced from 34.6mm to 2.59mm in position and from 9.08 degrees to 0.82 degrees in orientation. The timeto obtain the calibration data was 69 seconds. Three dimensional ultrasound imaging has the advantage that real time imagingis acquirable, regardless of organ shift or distortion. Our experimental results showed the proposed method was effective.

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This paper proposes a new non-contact impedance imager based on phase differential technique enabling an enhanceddetection of the existence of a tumor in tissues. The developed sensor is composed of an air supply system and two opticalfiber based distance sensors next to the air nozzle. For a periodic air pressure, two distance sensors provide us with sinusoidaloutputs with individual phases. The phase difference varies according to the change of mechanical impedance parameters oftissues between two points. A big advantage of the sensor is that the sensor can work irrespective of the color of tissues. Wealso confirmed the validity of the sensor for human lung.

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We have developed a novel robotic laparoscope for laparoscopic surgery to move the view point optically with double wedge prisms instead of moving the laparoscope itself. In this study, based on the problems that a previous invivo experiment pinpointed with the previous prototype, we redesigned a new prototype to widen the angle of view and thin the diameter of the laparoscope. The tube's diameter is thinned down into 18mm including a light source to fit in a commercial trocar. The prptotype has a view moving angle of ±19.2°, a view moving speed of 7.7°/s and a view moving error of 0.55±0.62mm at a distance of 100mm. It has an enough viewing area in the abdominal cavity and has a suffisient speed in the actual use. For the image quality, it maintains a high quality of image resolution, less distortion aberration and chromatic aberration. We received high evaluation marks for the image quality in the in-vivo experiment.

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