Thermal tissue damage caused by new endoscope model due to light absorption

Area of Science:

• Gastroenterology
• Medical Devices
• Endoscopy

Background:

• Bright endoscopic light sources enhance mucosal visualization.
• A new Olympus endoscopic system (2020) required modification due to reported heat-induced tissue damage during magnifying chromoendoscopy.
• The mechanism of thermal damage in the new system was investigated.

Purpose of the Study:

• To evaluate the temperature changes in stained and unstained porcine mucosa using a new and a previous endoscopic system.
• To investigate the potential for heat-induced tissue damage during magnifying chromoendoscopy.

Main Methods:

• Infrared imaging assessed surface temperatures of porcine mucosa stained with India ink, crystal violet, methylene blue, or indigo carmine.
• Temperatures were measured using the new (EVIS X1; GIF-EZ1500) and previous (EVIS EXERAIII; GIF-H190) endoscopic systems.
• Histological analysis examined tissue damage in crystal violet-stained mucosa after contact with the new endoscope.

Main Results:

• The new endoscope caused surface temperatures to exceed 70°C on stained mucosa (excluding indigo carmine), while unstained mucosa remained below 40°C.
• Histological analysis showed cavity formation in crystal violet-stained porcine epithelium.
• The previous endoscope resulted in maximum surface temperatures below 60°C for stained mucosa and below 30°C for unstained mucosa.

Conclusions:

• Heat transfer via light absorption is a likely cause of heat-induced tissue damage with the new endoscopic system during magnifying chromoendoscopy.
• The findings highlight the need for modifications to prevent thermal injury with advanced endoscopic technologies.