The vasculature was clearly visualized in situ using the SF. The needle was aimed and easily inserted into the basilic or brachial vein, and the needle tip visualized at its expected location. Successful vascular access was obtained with all 15 subjects, 13 of 15 on the first attempt, and 2 of 15 on the second attempt. 3 of the 15 lines encountered mild blurriness looking through the SF due to inconsistent optical properties of the probe cover.