American Society for laser medicine and surgery: Ninth annual meeting, poster abstracts

• Publisher: John Wiley and Sons
• Year: 1989
• Tongue: English
• Weight: 646 KB
• Volume: 9
• Category: Article
• ISSN: 0196-8092
• DOI: 10.1002/lsm.1900090614

✦ Synopsis

Temperature (T) regulation of thermal devices during arterial recanalization may be critical to avert extensive thermal damage. Eighteen patients (pts) underwent peripheral artery recanalization using a thermal-optical probe ("Hybrid"). T was monitored at the probe tip using a K-type thermocouple and displayed on a computer screen in real time during procedure. Laser angioplasty of totally occluded superficial femoral arteries (6.1t4.6 cm; mean IengthiSD) was done percutaneously (16 pts) or intraoperatively (2 pts). Argon laser irradiation was done using increments of 1 Watt (W) [range 5-14 W] for 1 sec pulses and 0.2 sec intervals. During irradiation, T rose at a rate of 40+_25°C/sec (meaniSD). Probe cooling occured at a rate of 65140 W s e c (p<O.Ol). Mean recanalization T in 14 pts was 156i86OC (range 64.342%) and mean time for recanalization was 9.5110.2 sec. Highest T was noted in calcific plaque and intraoperatively, whereas shorter recanalization time had lower T. In 1 case, optical fiber fracture was detected by a drop in T to baseline. Perforation occurred in 4 arteries at peak T range of 73 to 502°C. Saline flush during laser irradiation reduced T peak by 30%. All recanalized arteries were patent immediately and ten at follow-up ( 5.7i4 months). C O N C L U S I O N S : 1) recanalization T had a wide range, 2) perforations were not predicted by T, 3) T rise was slower than cooling rates, 4) T monitoring could detect probe malfunction.

Monitoring of T with feedback control may provide a mechanism to avoid irreversible thermal damage of arteries during laser recanalization. This could be especially useful in small vessels such as the coronary arteries.