Implantable Parylene-Based Wireless Intraocular Pressure Sensor

論文發表人:Po-Jui Chen (陳柏瑞), 加州理工學院電機工程學系

 

http://www.mems2008.org/

 

這篇論文提出了一新穎之可植入式無線被動壓力感測器以作為眼科醫學用途. 藉由運用面微加工出之可變電容與可變電感, 我們能夠設計出兩種不同的感測器來達到壓力感測的效果. 此感測器的單晶圓製程中使用了一高分子(parylene)作為具有生物相容性的結構材料, 且其製成的尺寸控制在一定範圍內, 故可降低相對應的眼內植入手術的困難度. 測試結果顯示了此微感測器能夠在壓力反應中達到高於7000 ppm/mmHg的靈敏度以及mmHg等級的解析度. 而在超過150天的活體動物實驗中, 我們也成功驗證了此植入元件能夠在眼內環境中保持穩定而未觸發任何的排斥反應. 此感測器最終將會被植入在玻璃體膜上或虹膜上, 以實現為青光眼患者不間斷地(24/7)監測眼內壓的可能性.

This paper presents a novel implantable, wireless, passive pressure sensor for ophthalmic applications. Two sensor designs incorporating surface-micromachined variable capacitor and variable capacitor/inductor are implemented to realize the pressure sensitive components. The sensor is monolithically microfabricated using parylene as a biocompatible structural material in a suitable form factor for increased ease of intraocular implantation. Pressure responses of the microsensor are characterized on-chip to demonstrate its high pressure sensitivity (>7000 ppm/mmHg) with mmHg level resolution. An in vivo animal study verifies the biostability of the sensor implant in the intraocular environment after more than 150 days. This sensor will ultimately be implanted at the pars plana or iris of the eye to fulfill continuous intraocular pressure (IOP) monitoring in glaucoma patients.