This paper proposes a micro pneumatic suction device for medical diagnosis and operation. We are interested in the practical applications of medical MEMS devices to minimally invasive medical operation. Guaranteeing relative positioning between medical MEMS and the pulsative object in the body is becoming indispensable. The micro suction device is proposed to fix the medical MEMS on a surface of the pulsating target part. This paper describes the suction device integrated with medical MEMS. A temperature sensor and micropump for DDS are integrated with the suction devices as typical sensor and actuator. An in- vitro experiment validated the feasibility of the proposed suction device as an assistive medical interface. Furthermore, an in- vivo trial of local DDS and local temperature sensing were successful. The proposed micro pneumatic suction device for medical diagnosis and operation will contribute to practical application of medical MEMS devices.

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We developed an oral-rehabilitation robot WAO-1 for use in cases of oral disorders such as TMJ (Temporomandibular Joint) disorder and dry mouth. WAO-1 is the first robot designed to provide massage to the facial tissues of a patient with oral disorders. This robot provides massage to the masseter and temporal muscles and to the parotid gland and duct with simple operation. It consists of two 6-DOF arms with plungers, a body with head rest, a control box, a PC, and an automatic massage trajectory control system with virtual compliance control. The massage trajectories are generated using the face shape model of an adult male before the massage. During the massage, compliance displacement xcc is calculated based on the reaction force from the face in real time. Using the virtual compliance control, it is possible to apply the massage trajectories made from the facial shape model of an adult male to many people without modification of the model.

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We propose a new evaluation method for video of tele-neurosurgery under microscopic view. We conducted a subjective evaluation of video by 16 evaluators to determine the minimum video bit-rate required to make decisions in tele-neurosurgery under microscopic view. In this evaluation, we developed a new evaluation method that is unaffected by learning from evaluating the same videos more than one. Our results showed that a video bit-rate of at least 384 kbps was necessary in order to make decisions in tele-neurosurgery. Also, contrary to general expectation, the expert subjects scored the low quality bit-rate videos higher than the residents subjects did. Moreover, if the quality of the original picture was poor, the evaluation result was not related to the compression ratio. These finding should be took into account in future evaluation of tele-surgery systems.

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In order to predict intraoperative brain tissue deformation after dura opening, our research group developed the threedimensional finite element brain model (whole model). Gravity induced brain shift in the case of left fronto-temporal craniotomy was simulated with the whole model. However, long computation time was required. The goal of this study is achieving drastic computation time reduction of brain shift simulation for future clinical application by developing a new finite element brain model. Since the deep zone, e. g. areas around third ventricle, exhibited smaller amount of brain shift than the superficial zone of left temporal lobe, authors proposed a new left hemispherical brain model without right cerebral hemisphere. Equivalent force boundary conditions were introduced and then applied to the cross section of the hemispherical brain model. In the numerical simulation, gravity induced brain shift of the left cerebral hemisphere was computed by ABAQUS/Explicit. The results obtained by the proposed hemispherical brain model were good agreement with that by the whole model except only part of cerebellum and brain stem. In this analysis case, deformation of adjacent area of the left temporal lobes is especially important. The displacement error between proposed and whole models around cerebellum and brain stem are acceptable since these areas are away from the surgical field. The brain shift analysis using the proposed model successfully achieved up to 61% reduction of computation time compared with that using the whole model. The computation time reduction capability of the proposed model was successfully demonstrated.

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