The Scalable Effects Simulation Environment for thermal modeling of laser-tissue interactions in aid of optical system design

Most label-free optical techniques rely on laser illumination for biomedical imaging, which, at high irradiance, can cause tissue heating, changes in material properties, and permanent damage. Simplified analytical models are used to predict temperature rises at a low computational cost. However, they are only reliable under ideal conditions and lack spatial accuracy, which can affect the assignment of correct laser parameters. In this study, we demonstrate that the Scalable Effects Simulation Environment improves the accuracy of modeling spatiotemporal thermal gradients by integrating light propagation in a semi-infinite medium with spatially inhomogeneous heat transfer. The computational model is applied to two representative cases: (1) intraoperative identification of the parathyroid gland and (2) biochemical characterization of the esophagus using a scanning Raman endoscope. For each application, subtle discrepancies between simplified analytical models and the computational model are identified. (1) Accounting for convective and evaporative cooling during surgery can reduce the exposed tissue’s surface temperature by 2-3 ◦C. (2) An optimal speed of 1 revolution per second is found to minimize heat accumulation in the design of a rotating endoscope. These initial findings highlight limitations of generalized analytical models and underscore the need for detailed, application-specific thermal modeling to drive innovation in diagnostic and exploratory optical applications.