Methylene Blue Spray as a Tool for Safe Thyroidectomy

Background The complex surgical anatomy and intricate structural arrangement of the thyroid region pose significant challenges for surgeons in identifying the parathyroids and recurrent laryngeal nerve (RLN) during thyroid surgeries. Therefore, it is crucial to develop techniques that enhance the identification of these structures and reduce complications during thyroidectomies. Objective This study intends to assess the efficacy and diagnostic value of Methylene Blue dye and its usefulness in identifying, conserving and minimizing injury to parathyroid glands and recurrent laryngeal nerve during thyroidectomies. Methods Over two years, 66 patients had near-total, subtotal, or total thyroidectomies at the Shri BM Patil Medical College, Hospital & Research Centre, Vijayapura, India, as part of this interventional study. The time it took for various tissues to return to their natural colour after applying methylene blue dye was the principle used for safe thyroidectomy. Preoperative serum calcium and parathyroid hormone (PTH) concentrations, preoperative diagnoses, and demographic information were gathered for the study. Documentation was also kept of the histological confirmation, hospital stay following surgery, complications following surgery, variations in blood calcium and PTH concentrations on the fifth postoperative day, and any allergic reactions to methylene blue. This allowed for the calculation of equal sensitivity and specificity with negative and positive predictive values. Results Sixty-three (95%) of the 66 patients were female, most in their 40s-60s. Before surgery, patients' serum PTH and calcium levels were normal, with no patients having hoarseness of voice or hypocalcemia symptoms. Postoperative hospital stays typically lasted three to five days. Two patients experienced vocal cord paresis following surgery, and one patient experienced delayed wound healing. They were eventually able to recover fully. On day five following surgery, there was no drop in serum PTH or calcium levels and no allergic reaction to methylene blue. Methylene blue showed a sensitivity of 98.46%, specificity of 97.01%, positive predictive value of 96.97%, negative predictive value of 98.48%, and overall accuracy of 97.73% when used for intraoperative structure detection. Conclusion Using methylene blue dye for the intraoperative identification and preservation of parathyroid glands and the recurrent laryngeal nerve is a reliable, affordable, and accessible method with good sensitivity and specificity. It makes thyroidectomy dissections less taxing and reduces the risk of complications following thyroid operations.