ULTRASONIC TELEMETRIC IMPLANTABLE PULSED DOPPLER BLOOD FLOW VELOCITIMETER FOR SMALL ANIMALS

TITLEUltrasonic Telemetric Implantable Pulsed Doppler Blood Flow Velocimeter for Small Animals ABSTRACT Ultrasonic Pulsed Doppler devices for measuring flow velocities in blood vessels of small animals such as mice are routinely used by cardiovascular researchers for preclinical researchUndisturbed and non tethered acquisition of physiologic data in awakeunanesthetizedanimals using wireless telemetry is the most realistic way to study physiological functionHoweverdue to the lack of suitable devicesthese studies at present are done under anesthesia which can be problematic in physiological and pharmacological studies because all anesthetic agents alter basal cardiovascular parameters and control in some wayTo allow researchers to monitor blood flow velocities in undisturbeduntetheredawake mice serially over the course of several months to facilitate longitudinal cardiovascular and aging studies we propose to develop aMHz Ultrasonic Implantable Pulsed DopplerIPDtelemetric deviceThecc volume IPD will be implanted in the peritoneal cavity and connected to aMHz ultrasonic single crystal transducer cuff probe that is placed around the blood vessel of interestaortaabdominal renal carotid arteriesWe will use the commercially available Doppler Flow Velocity Systemand the Small Animal Implantable Telemetry Systemboth of which are manufactured by usas a starting point to accomplish our objective with the following specific aims in phase IAIMDevelopMHz wireless power transfer charging system for rodent cagesAIMDevelop a compactcc volumeultrasonic Doppler blood flow velocimeterAIMRecord mouse aortic blood flow measurements in amonth study During phase II we will refineminiaturizeand reduce power consumption of the Pulsed Doppler electronics using custom CMOS silicon integrated circuit designconductmonth long term studies inmiceand update the backend data acquisition system in preparation for commercial manufacture and sale of the IPDs to researchers worldwideOur specific innovations areUnder the cage wireless power transfer for continuous for long term useUltra low power Doppler electronics suitable for long term operationandCompact Doppler electronics to enablecc telemetric deviceThe proposed device will advance the state of the art in preclinical cardiovascular and aging research by allowingUndisturbeduntetheredphysiologically realistic blood flow velocity measurements in awake miceMonitoring of cardiovascular changes in longitudinal pharmacological studies formonthsThe proposed device may also be applicable for cardiovascular function assessment in aging studies lasting up tomonths PROJECT NARRATIVE Mice are used extensively to study cardiovascular function in disease through measurements of blood flow velocity in their arteries and veinsIn mice these measurements are made noninvasively but under anesthesia which can alter the baseline cardiovascular parametersIn the proposed research we will develop an implantable wireless telemetry device and system that can longitudinally measure blood flow velocity in awake animals without disturbing themThis will allow for proper measurements of cardiovascular function and the development of appropriate treatment strategies in mice that may potentially lead to solutions that are translatable to humans