[In vitro studies on pulsed laser angioplasty in liquid and gaseous medium].
OBJECTIVE
In a vascular model the mechanisms of a pulsed dye laser working in a liquid and a gaseous environment was tested and documented by means of a high-speed camera.


METHODS
The pulse application (630 nm wavelength) on a target of calcified arterial plaque material was detected at intervals of 20 microseconds up to 800 microseconds total time.


RESULTS
In water the laser beam created a cavitation bubble which expanded from 0 to 450 microseconds from a radius 0 to 3 mm and collapsed afterwards. The average expansion velocity of the bubble was 80 m/s in the first 20 microseconds and the resulting velocity of the tube model wall was 10 m/s. Compared with gaseous atmosphere there was no bubble and consecutively no wall stress.


CONCLUSIONS
It is obvious that laser angioplasty causes wall stress and destruction of different vascular layers. This might be the initial stimulation for restenosis. In gaseous atmosphere laser angioplasty should be more protective.
Zwaan
M
M
Institut für Radiologie, Medizinischen Universität, Lübeck.
Behnle
U
U
Engelhardt
R
R
Vogel
A
A
Kloess
W
W
Birngruber
R
R
Weiss
H D
HD
D016342:Angioplasty, Laser / Q000379:methods*; D001158:Arteries / Q000601:surgery; D002114:Calcinosis / Q000601:surgery; D002245:Carbon Dioxide; D008953:Models, Anatomic; D014867:Water
D014867:Water; D002245:Carbon Dioxide