Surgery assistance system for continuous resection of brain tumors-proposal of continuous tumor resection forceps, tumor cell separation, dehydration, and isolation mechanism.

The tumor resection ratio must be improved due the increased possibility of recurrence or malignancy. The purpose of this study was to develop a system that includes forceps with a continuous suction function and flow cytometry to diagnose the malignancy of the tumor for safe, accurate, and effective surgery. A newly developed continuous tumor resection forceps consists of a triple pipe structure, which enables continuous suction of the tumor by integrating the reflux water and suction system. The forceps includes tip opening/closure detection switch to control the adsorption and suction strength when tip is opened and closed. To perform accurate tumor diagnosis using flow cytometry, a filtering mechanism was developed for dehydrating reflux water from continuous suction forceps. In addition, a cell isolation mechanism comprising a roller pump and shear force loading mechanism was also newly developed. By using a triple pipe structure, a significantly larger tumor collection ratio was observed compared to the previous double-pipe structure. By performing suction pressure control with the opening/closure detection switch, inaccurate suction can be prevented. By widening the filter area of dehydration mechanism, it was possible to improve the reflux water dehydration ratio. The most appropriate filter area was 85 mm2. By using a newly developed cell isolation mechanism, the processing time can be reduced to less than 1/10 of the original time, keeping the same cell isolation ratio, when compared to the existing pipetting method. Neurosurgery assistance system with continuous tumor resection forceps and a cell separation, dehydration and isolation mechanism was developed. An effective and safe tumor resection, accurate and fast diagnosis of malignancy can be achieved by using the current system.

Microsuture-tying forceps with attached scissors for bypass surgery.

BACKGROUND: Bypass surgery requires the shortest temporary occlusion time of a recipient artery during anastomosis. For this purpose, we have devised a microforceps with attached scissors that makes it possible to perform the multiple steps involved in anastomosis without exchanging instruments. This microforceps avoids having to exchange instruments twice in one suturing, such as that between a microsuture-tying forceps or a microneedle holder and microscissors in conventional methods. METHODS: The instrument is made of stainless steel and is 15.5 cm long. Using this microforceps with scissors, we can suture, tie, and cut a ligature fluently for consecutive sutures without exchanging instruments. The mean time during one suturing was compared between two patient groups treated by conventional method and with use of this instrument. RESULTS: This instrument was used for 34 patients with ischemic cerebrovascular disease (including three who needed deep-site anastomoses) and allowed us to perform superficial temporal artery-middle cerebral artery (STA-MCA) anastomoses uneventfully. This instrument saved 15.2 s in the mean time during one suturing. CONCLUSIONS: Although it is of paramount importance to practice tying sutures well, this new instrument removes the need to exchange conventional instruments, and we believe it will save time and, therefore, decrease complications during bypass surgery.