A Force-Visualized Silicone Retractor Attachable to Surgical Suction Pipes.

This paper presents a force-visually-observable silicone retractor, which is an extension of a previously developed system that had the same functions of retracting, suction, and force sensing. These features provide not only high usability by reducing the number of tool changes, but also a safe choice of retracting by visualized force information. Suction is achieved by attaching the retractor to a suction pipe. The retractor has a deformable sensing component including a hole filled with a liquid. The hole is connected to an outer tube, and the liquid level displaced in proportion to the extent of deformation resulting from the retracting load. The liquid level is capable to be observed around the surgeon's fingertips, which enhances the usability. The new hybrid structure of soft sensing and hard retracting allows the miniaturization of the retractor as well as a resolution of less than 0.05 N and a range of 0.1-0.7 N. The overall structure is made of silicone, which has the advantages of disposability, low cost, and easy sterilization/disinfection. This system was validated by conducting experiments.

Force-Sensing Silicone Retractor for Attachment to Surgical Suction Pipes.

This paper presents a novel force-sensing silicone retractor that can be attached to a surgical suction pipe to improve the usability of the suction and retraction functions during neurosurgery. The retractor enables simultaneous utilization of three functions: suction, retraction, and retraction-force sensing. The retractor also reduces the number of tool changes and ensures safe retraction through visualization of the magnitude of the retraction force. The proposed force-sensing system is based on a force visualization mechanism through which the force is displayed in the form of motion of a colored pole. This enables surgeons to estimate the retraction force. When a fiberscope or camera is present, the retractor enables measurement of the retraction force with a resolution of 0.05 N. The retractor has advantages of being disposable, inexpensive, and easy to sterilize or disinfect. Finite element analysis and experiments demonstrate the validity of the proposed force-sensing system.

Visualization method based stiffness sensing system for endoscopes.

This research developed novel stiffness sensing system attachable to endoscope. The system is an extension of our previous force sensing systems utilizing force visualization mechanism. The sensing part is attached to endoscopes. The force is visualized at the sensing part, and can be measured as visual information via endoscopes. The sensing part also has a structure of limiting the pressing amount. By measuring force at the limitation, the stiffness can be measured. The developed sensing part has the features of no electrical components, disposable, simple, easy sterilization, MRI-compatibility, and low-cost. The validation of the system was experimentally shown.

[Case report: lymph node metastasis of micropapillary bladder tumor that completely responded to radiation therapy].

A 67-year-old woman was referred to our hospital in April 2003 because of a bladder tumor. Cystoscopy revealed a thumb tip size and wide based papillary tumor. TUR-Bt was performed. Histologically, the tumor was UC, G3 and pT1. There was no recurrence of tumor in bladder after that. 3 years later, she was referred again with high serum levels of CA19-9 and CEA. Computed tomography showed bilateral lymph node swelling in the pelvis. An open biopsy of the lymph node was done and it contained UC with a micropapillary component. Radiation therapy achieved completely response. Serum levels of CA19-9 and CEA were within normal limits. She has never had a recurrence of tumor until July 2007.