title: Microsystems technology in radiation therapy.
abstract: In this paper, we present several implantable micro-devices targeted towards improving the efficacy of radiation therapy. Three micro-devices are discussed: a self-biased solid state dosimeter to be used for wireless monitoring of the delivered dose, an electromagnetic tracking system to locate the position of tumor in real-time, and a Guyton-chamber-embedded capacitive pressure sensor for wireless measurement of interstitial pressure inside a tumor. Dosimeter and tracking systems are developed to be integrated together to achieve a track-able radiation sensor. Guyton chamber of the pressure sensor will eliminate the sensor drift due to the interaction of cells and fibrous tissue with sensor's membrane. The dosimeter has a sensitivity of up to 9 kΩ/Gy and a dynamic range of 10 Gy, when operating with a zero bias voltage. The tracking system is able to track a tumor that is 60 cm away with a resolution of 2 mm and a dynamic range of up to 5 cm. Finally, the capacitive pressure sensor has a sensitivity of 75 fF/kPa and a dynamic range of 60 mmHg.
authors.affiliation: School of Electrical and Computer Engineering at Purdue University, West Lafayette, IN 47907, USA.
authors.forename: T
authors.initials: T
authors.lastname: Maleki
authors.forename: B
authors.initials: B
authors.lastname: Ziaie
mesh_terms: D015374:Biosensing Techniques; D004307:Dose-Response Relationship, Radiation; D025802:Electric Capacitance; D055590:Electromagnetic Phenomena; D008855:Microscopy, Electron, Scanning; D055616:Microtechnology / Q000295:instrumentation* / Q000379:methods*; D009369:Neoplasms / Q000532:radiotherapy*; D011312:Pressure; D011874:Radiometry; D059015:Wireless Technology