Biomed. Opt. Express 6, 2552–2561 (2015)

Credit: OSA

Ultrashort near-infrared laser pulses can ablate subsurface plaque from the walls of arteries without causing surface damage, report scientists in Switzerland. Thomas Lanvin and co-workers from École Polytechnique de Lausanne and the University of Fribourg used optical coherence tomography (OCT) to study the effect of laser pulse energy on the ablation of plaque in mouse aortas. The laser pulses remove the plaque by vaporization. A 20 W, 1,030 nm wavelength fibre laser with tunable pulse duration, energy and repetition rate was used in the experiments. The team selected pulses with a duration of 1.5 ps and a repetition rate of 1 kHz to mitigate nonlinear self-focusing effects and reduce heat accumulation in the sample, while still being sufficient to perform ablation. The team concluded that pulse energies of 4 μJ or less were able to provide the required ablation without inducing surface damage to the blood vessel.