Ultrasonography for the noninvasive assessment of tissue properties has enjoyed widespread success. With the growing emphasis in recent years on arteriovenous fistulae (AVFs) for dialysis vascular access in patients with end-stage renal disease, and on reducing AVF failures, there is increasing interest in ultrasound for the preoperative evaluation of the mechanical and elastic properties of arteries and veins. This study used high-resolution ultrasound with phase-sensitive speckle tracking to obtain in-vivo vein elasticity measurements during dilation. The results of this novel ultrasound technique were then compared to a computer model of venous strain. The computer model and ultrasound analysis of the vessel wall demonstrated internally consistent positive and negative longitudinal strain values as the vein wall underwent dilation. These results support further investigation of the use of phase-sensitive speckle tracking for ultrasound venous mapping for preoperative vascular access evaluation.