Interstitial Laser Photocoagulation Using 980 nm Diode Laser in Benign Thyroid Nodule: A Feasibility Study

Abstract

The aim of this study was to investigate the feasibility of using 980 nm diode laser for interstitial laser photocoagulation (ILP) before clinical application in benign thyroid nodule treatment. The bovine livers were cut into blocks to irradiate with 980 nm laser through the lumen of a 20-gauge spinal needle using a fiber optic guide. Laser irradiation was performed with the output power of 2 W and 3 W for 60, 120 and 180 seconds respectively. The liver blocks containing lesions were dissected along the axis of the fiber optic tracts and then cut transversely into slices. The thermal effect was evaluated by measuring the dimensions of the zone of coagulation necrosis. We present a case treated with 980 nm diode laser for the benign large thyroid nodule. All the irradiated areas zone measured in the gross specimens were 5.5 mm ± 1.4 mm (2 W, 60 s), 6.9 mm ± 1.4 mm (2 W, 120 s), 7.3 mm ± 0.5 mm (2 W, 180 s), 8.8 mm ± 2.2 mm (3 W, 60 s), 9.2 mm ± 0.8 mm (3 W, 120 s), 12.5 mm ± 4.1 mm (3 W, 180 s) respectively. The transverse diameter was as 5.1 mm ± 0.5 mm (2 W, 60 s), 6.1 mm ± 0.2 mm (2 W, 120 s), 9.9 mm ± 2.5 mm (2 W, 180 s), 6.2 mm ± 1.8 mm (3 W, 60 s), 7.7 mm ± 1.2 mm (3 W, 120 s), 8.8 mm ± 0.7 mm (3 W, 180 s) respectively. ILP was well tolerated and there was no complication. Interstitial laser photocoagulation with 980 nm diode laser induces well-defined tissue ablation correlated with energy parameters in bovine liver tissue and therefore, could be an efficient therapeutic tool in benign thyroid nodular disease.