Patent ID: 8529452
Filing Date: 2013-09-10
Classification: A61B,A61M

Abstract:
1. A method for operating an ultrasound system to detect maturation of an arterio-venous fistula in a subject, the arterio-venous fistula defining a lumen, comprising: transmitting ultrasound pulses into the subject from a transducer coupled to the ultrasound system; receiving ultrasound echoes at the transducer; constructing an ultrasound image of the fistula using data acquired from the received ultrasound echoes; calculating a wall thickness of the arterio-venous fistula based on a first distance between a first point in the ultrasound image corresponding to a first location on an outer wall of the arterio-venous fistula and a second point in the ultrasound image corresponding to a second location on an inner surface of the lumen; calculating a diameter or radius of the lumen of the arterio-venous fistula based on a second distance between third and fourth points in the ultrasound image corresponding to third and fourth locations, respectively, on the inner surface of the lumen, wherein the third point is diametrically opposed to the fourth point; calculating a circumferential stress based on the wall thickness and the diameter or radius of the lumen; comparing the circumferential stress to a predetermined threshold wherein the predetermined threshold is between about 7.00E+04 to 2.80E+05 N/m producing a notification that the arterio-venous fistula is mature if the calculated circumferential stress is less than or equal to the predetermined threshold.