Technical developments for cerebral thermal treatment: water-cooled diffusing laser fibre tips and...

Area of Science:

• Medical Devices
• Laser Surgery
• Thermal Ablation

Background:

• Laser-induced thermal ablation is a key surgical technique.
• Controlling lesion size and preventing thermal damage are critical.
• Current methods using diffusing tips face limitations in power delivery and tip integrity.

Purpose of the Study:

• To compare the efficacy of water-cooled versus non-cooled diffusing tips for laser thermal lesion generation.
• To evaluate the safety and control of thermal lesions produced by water-cooled tips.
• To assess the impact of water cooling on laser fiber tip durability and lesion characteristics.

Main Methods:

• In vitro studies on beef myocardium and in vivo canine models.
• Utilized a 980 nm diode laser with water-cooled and non-cooled diffusing tips.
• Employed two-plane magnetic resonance thermal imaging (MRTI) for real-time monitoring and feedback.
• Assessed lesion dimensions, charring, and tip failure at various power levels.

Main Results:

• Water-cooled tips withstood higher power (up to 9.5 W for 8 min) without failure, unlike uncooled tips which failed rapidly at lower power levels.
• Lesions produced with water-cooled tips showed significantly larger dimensions (up to 26.5 x 23.3 mm in vitro; 18.1 x 21.4 mm in vivo) and minimal charring.
• Uncooled tips resulted in charring and smaller lesions due to premature failure.

Conclusions:

• Water cooling significantly enhances the safety and effectiveness of laser diffusing tips.
• Higher power delivery is achievable with water-cooled tips, leading to larger and better-controlled thermal lesions.
• Two-plane MRTI is a valuable tool for precise monitoring and control during laser thermal ablation procedures.