Noninvasive determination of perfused blood vessel dimensions using a pressure-diameter relationship

Based on the decisive effects of the hemodynamic/mechanical environments on the development and remodeling of arteries in vivo, several groups have cultured tissue-engineered vessels in various mechanically active perfusions systems leading to the consensus that a mechanically active environment is beneficial for the engineered vessels. To facilitate the interpretation and design of such studies, accurate estimates of the applied forces and resulting stresses are required which in turn require an accurate estimate of vessel dimensions. Here we present and validate a simple technique that uses the measured pressure drop along the length of the vessel to calculate the inner diameter, which when combined with the measured outer diameter, yields wall thickness and area. This approach requires only minor modification of existing perfusion systems and provides noninvasive real-time estimates of wall area within ∼10%.