Actual effective CO2 laser power on tissue in endoscopic surgery

Area of Science:

• Medical Physics
• Surgical Technology
• Endoscopic Laser Applications

Background:

• Carbon dioxide (CO2) laser surgery is widely used in endoscopy.
• Power reduction during endoscopic CO2 laser procedures can affect surgical outcomes.
• The precise effective power delivered to tissue is often unclear.

Purpose of the Study:

• To identify the causes of power loss in endoscopic CO2 laser surgery.
• To quantify the effective power delivered by CO2 lasers through various endoscopes.
• To establish a predictive model for CO2 laser efficacy in endoscopic procedures.

Main Methods:

• An experimental model was designed to test CO2 laser power transmission.
• CO2 laser beams were passed through a CO2 gas-pressurized chamber.
• Laser power output was measured after transmission through different endoscopic instruments, including single- and double-puncture laparoscopes and a hysteroscope.

Main Results:

• No significant power loss was observed when a CO2 laser beam passed through a CO2 gas-pressurized chamber.
• A direct correlation was found between the internal diameter of the endoscope and the laser's power output.
• Effective power delivered was 92% for single-puncture laparoscopes, 85% for double-puncture laparoscopes, and 48% for hysteroscopes.

Conclusions:

• Endoscope internal diameter, not CO2 gas, is the primary factor in CO2 laser power reduction during endoscopic surgery.
• Effective power varies significantly depending on the specific endoscope used.
• These findings are crucial for accurately predicting and optimizing CO2 laser effects in clinical endoscopic applications.