The effect of plaque composition on laser recanalization.

Laser recanalization using metal-capped laser fibers and continuous-wave laser energy occurs by thermal ablation of atherosclerotic plaque. Different types of plaque respond differently to laser energy and plaque composition may be an important determinant of the success of laser recanalization. To investigate this hypothesis, 16 patients with symptomatic arterial occlusions in the mid and distal superficial femoral artery underwent B-mode ultrasound arterial imaging prior to attempted argon laser recanalization. The composition of the occlusions was classified as soft (echogenicity less than the adjacent arterial wall), dense (echogenicity equal to the adjacent arterial wall), or calcified (echoreflective). Recanalization was successful in 100% (8/8) of patients with soft occlusions versus 38% (3/8) with dense or calcified occlusions (P = 0.01). Thus, plaque composition as assessed by B-mode ultrasound imaging appears to be an important predictor of the success or failure of arterial recanalization using a thermal laser probe.