Temperature rises in the round window caused by various light sources during insertion of rigid endoscopes: an experimental animal study

Abstract

The endoscopic instruments used in middle ear surgery caused the temperature of the round window to rise. The rise varied with endoscope diameter and the type of light source used.

The effect of light intensity on image quality in endoscopic ear surgery

“…Due to these concerns, a number of studies have arisen with the aim of measuring variables influencing maximal temperatures produced by the endoscope . Ito et al, measured a maximal temperature of 110°C at the tip of a 4‐mm endoscope illuminated by a 100% Xenon light source, but 61.5°C when the endoscope diameter was reduced to 2.7 mm.…”

“…With use of the LED light source, maximal temperatures were further reduced to around 45°C and 41°C at 100% and 50% light intensity, respectively . In guinea pig temporal bones, another group reported that when intensity of the light source is reduced to 50%, temperatures fell to 35% of maximal . Therefore, these groups have all recommended reducing light intensity to the lowest possible level …”

“…In guinea pig temporal bones, another group reported that when intensity of the light source is reduced to 50%, temperatures fell to 35% of maximal . Therefore, these groups have all recommended reducing light intensity to the lowest possible level …”

“…Due to these concerns, a number of studies have arisen with the aim of measuring variables influencing maximal temperatures produced by the endoscope. 4,9,12,[14][15][16] Ito et al 14 Raters were asked to evaluate each photograph on a 5-point Likert score (1 = significantly worse than average; 5 = significantly better than average). SD, Standard Deviation.…”

Meningoceles and Meningo-Encephaloceles of the Sphenoidal Sinus: Neuroendoscopic Perspectives

“…Only the frequent and regular use of Endoscopic Endonasal Neurosurgery allows to become and to stay proficient. In the future, further technological improvement of diagnostics, intraoperative neuronavigational guidance and of neuroendoscopic imaging (25), including low temperature LED illumination and 3-D-imaging will increase the surgical precision: With the usual 4-mm rigid HOPKIN's endoscopes (0 0 , often also 30 0 and 70 0 in the lateral spenoid sinus) connected to Xenon light sources, temperatures at the endoscope tip of up to 91 0 C, with 30 0 even of 95 0 C may be reached (26), with the risk of significant heat damages , whereas the new LED light sources are less critical (26,27). 3-D-Endoscopy, e.g.…”