The effects of dynamic optical properties during interstitial laser photocoagulation

Abstract

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An investigation of the use of transmission ultrasound to measure acoustic attenuation changes in thermal therapy

“…This indicates that BSA is a temperature-sensitive marker and furthermore that the polyacrylamide phantoms are resistant to the temperature-time exposures of this study. The change in acoustic properties with BSA content could thus be used to model dynamic acoustic changes in tissue properties during ultrasound heating, akin to studies done for laser thermal therapies [12], important for computational model validation.…”

Considerations for Thermal Injury Analysis for RF Ablation Devices

“…The most common of these is the method of cumulative equivalent minutes. Several investigators have noted that for each degree increase above 43°C in temperature, there is approximately a two-fold decrease in the time required to achieve the same biological effect [28][29][30][31][32][33]. The equivalent time for each second of exposure to temperatures greater than 43°C is calculated by the isoeffect equation [33]: t exp = t critical * 2 (T exp 43) Eq.…”

“…For a specified exposure temperature and time, the Arrhenius fit parameters determine the probability of cell damage. Arrhenius parameters have been determined in several body tissues, including the liver at high temperatures [31][32][33]38]. In the majority of studies, temperature and tissue injury profiles are calculated sequentially, meaning that Arrhenius calculations are not made until temperature calculations are completed [29][30].…”

Interstitial photoacoustic technique and computational simulation for temperature distribution and tissue optical properties in interstitial laser photothermal interaction

“…9,10 And temperature distribution in biological tissues has been of interest in photothermal processes. Current noninvasive methods to measure tissue temperature include infrared thermography, [11][12][13] ultrasound thermograph, 14 and magnetic resonance thermometry (MRT).…”