A Numerical Study of Gold-Nanorod-Enhanced Noninvasive Laser Ablation for Central Lung Cancer Using an Optical-Thermal-Fluid Model

Abstract Central lung cancer presents significant challenges due to its proximity to vital thoracic structures, making traditional treatments often less effective and more harmful. Laser ablation (LA) has emerged as a promising minimally invasive therapy, particularly when enhanced with gold nanorods (GNRs), which possess unique optical properties that amplify the effects of LA. This study introduces a comprehensive optical-thermal-fluid model designed to simulate the spatiotemporal distributions of GNRs and temperature involved in the noninvasive GNR-enhanced LA for central lung cancer. The effects of GNR enhancement on heat transfer and tumor ablation were investigated with regard to three cases of central lung cancer in different sizes and locations. The results demonstrate that GNRs significantly improve the heating efficiency within smaller tumors by concentrating laser energy, thus reducing the time needed to reach therapeutic temperatures. However, in larger tumors, particularly where the tumor size approaches the penetration depth of the laser, the GNRs cause substantial photon absorption near the emission surface, resulting longer treatment durations attributing to heat transfer. Nevertheless, GNRs consistently confine the thermal energy, minimizing damage to surrounding healthy tissue in tumors. This study highlights the potential of GNR-enhanced LA as a noninvasive treatment for central lung cancer. It also underscores the importance of considering tumor size in the treatment planning of GNR-enhanced LA.