The human body is comprised of a series of pressurized vessels, including muscles, organs, abdominal and thoracic compartments. One such vessel is the intra-abdominal volume, or volume contained by the peritoneum, pressurized by intra-abdominal pressure (IAP). Existing clinically-accepted IAP measurement techniques are invasive and not inter-rater reliable. As such, it is the effort of this research to develop a direct, non-invasive, handheld tool to measure internal pressures in pressurized, physiological vessels. The novel device uses a localized known pressure (namely aspiration) to measure resulting tissue deformation, from which internal pressures can be divulged considering the extended Hencky solution. Two male participants were tested to validate the theoretical device function for IAP measurement. Participants' Young's moduli of the abdominal wall were calculated with measured IAP values. Results were consistent with participant body mass indices and overall health. Average measured IAP was 0.42 kPa and 0.46 kPa at supine and inclined positions, respectively. Average measured abdominal wall elasticity was 14.91 kPa and 23.09 kPa at supine and inclined positions, respectively. These preliminary findings suggest the potential use of the device described herein as a measurement system for pressurized vessels, whereas the system will be tested on a larger sample size before recommending clinical use.