Development of a Phacoemulsifier with an Intracameral Pressure Control Function

Research Project

Project/Area Number	13555119
Research Category	Grant-in-Aid for Scientific Research (B)
Allocation Type	Single-year Grants
Section	展開研究
Research Field	Control engineering
Research Institution	KYOTO UNIVERSITY
Principal Investigator	ARAKI Mituhiko Kyoto University, Graduate School of Engineering, Professor, 工学研究科, 教授 (60026226)
Co-Investigator(Kenkyū-buntansha)	KYOIZUMI Kozo Santest Co. Ltd., Technical Division, Director, 技術部長 FURUTANI Eiko Kyoto University, Graduate School of Engineering, Associate Professor, 工学研究科, 助教授 (40219118)
Project Period (FY)	2001 – 2002
Project Status	Completed (Fiscal Year 2002)
Budget Amount *help	¥6,100,000 (Direct Cost: ¥6,100,000) Fiscal Year 2002: ¥2,400,000 (Direct Cost: ¥2,400,000) Fiscal Year 2001: ¥3,700,000 (Direct Cost: ¥3,700,000)
Keywords	cataract surgery / phacoemultification-aspiration / intracameral pressure control / differential regulation / surge phenomenon / 状態予測制御
Research Abstract	Safe phacoemulsification requires stable anterior chamber. In this research, we have developed an intracameral pressure controller for a phacoemulsifier. To be concrete, 1) two control methods of the intracameral pressure, constant regulation method, which is to maintain the intracameral pressure at a constant level, and differential regulation method, which is to suppress the rate of change of the intracameral pressure, were proposed and evaluated by experiments, 2) an estimation method of the intracameral pressure was studied, and 3) an actuator for the intracameral pressure control was developed and evaluated by experiments. The obtained results are as follows. ・ Both control methods have enough performance of intracameral pressure control, and the differential regulation method is more appropriate from the viewpoint of the safety and the possibility of implementation. ・ By comparing the pressures at the infusion side and at the suction side with that in the anterior chamber, it is confirmed that the change of the pressure at the infusion side is highly similar to the change of the pressure in the anterior chamber. From this result, we can use the pressure at the infusion side for intracameral pressure control. ・ An actuator for the differential regulation of the intracameral pressure, which is small enough for a phacoemulsifier, was developed, and it was confirmed that it has enough performance of intracameral pressure control by experiments. As mentioned above, the developed controller has enough performance of intracameral pressure control and safety for clinical application. It will contribute to improvement in safety of phacoemulsification-aspiration surgery.