Clinical Research Directory

Huaxi Tunnel Technique For Recurrent Laryngeal Nerve Exposure And Dissection In Thyroid Surgery

Protection of the recurrent laryngeal nerve (RLN) is a key focus and difficulty in thyroid surgery. Unilateral RLN injury can lead to ipsilateral vocal cord paralysis, resulting in hoarseness in patients postoperatively. Bilateral RLN injury, however, may cause bilateral vocal cord paralysis, leading to dyspnea and even asphyxiation; in severe cases, tracheotomy and permanent tracheal cannulation are required. Consequently, RLN injury significantly impacts patients' postoperative quality of life and career development. Guidelines and consensuses both domestically and internationally recommend that during the management of the posterior thyroid capsule, active detection, exposure, and dissection of the RLN, combined with meticulous capsular dissection along the RLN, should be performed to effectively reduce the incidence of RLN injury. While active anatomical identification of the RLN can clarify the nerve branches and their relationship with surrounding tissues, facilitating surgical procedures such as ligation and hemostasis, the traditional method of dissecting with instruments like hemostats or right-angle forceps (either blunt or sharp dissection along the nerve surface) increases the risk of nerve injury due to traction, clamping, or thermal damage. This is particularly challenging for less experienced surgeons, who face great difficulties in using energy devices near the RLN without causing injury-a major concern in the field of thyroid surgery. Diluted epinephrine solution exhibits excellent hemostatic effects in local surgery, improves surgical field clarity, and shortens operation time. Its safety has been clinically verified, and it is commonly used in plastic and cosmetic surgery, joint surgery, and the cavity creation process of endoscopic thyroid surgery. Based on this, this study innovatively proposes the "Huaxi Tunnel Technique": on the basis of meticulous posterior capsular dissection in traditional thyroid surgery, the RLN detection point on the posterior capsule below the lower pole of the thyroid is located using the "cross method" and exposed. A syringe containing diluted epinephrine solution is then used, with its front hose inserted along the RLN towards the laryngeal entry direction. Rapid injection is performed, and the pressure generated by this injection separates the fibrous connective tissue on the RLN surface, forming a "tunnel" from the RLN detection point to the laryngeal entry site-thus achieving exposure and dissection of the RLN. This technique offers multiple advantages: epinephrine reduces local bleeding, enhancing surgical safety and the convenience of meticulous capsular dissection; tunnel formation causes edema and discoloration of the fibrous connective tissue in the posterior thyroid capsule (while the parathyroid glands remain uncolored), facilitating the rapid identification and protection of the parathyroid glands. Preliminary preclinical experiments have confirmed that the technique reduces the difficulty of RLN exposure and dissection, decreases intraoperative bleeding and complication rates, and improves the safety of thyroid surgery. To further evaluate the efficacy, safety, and operability of this tunnel technique for RLN exposure and dissection, a prospective single-blind randomized controlled trial comparing it with traditional thyroid surgery methods is hereby conducted.

Mecobalamin in Promoting Recurrent Laryngeal Nerve Function Recovery After Thyroid Surgery

Recurrent laryngeal nerve injury is one of the most common and serious complications affecting quality of life after thyroid surgery. Intraoperative traction, clamping, thermal injury, or direct transection can lead to its dysfunction. Unilateral injury causes vocal cord paralysis, manifesting as hoarseness, coughing while drinking, and vocal fatigue; bilateral injury can result in severe dyspnea, potentially requiring tracheotomy and posing life-threatening risks. Although intraoperative neuromonitoring has reduced the risk of permanent injury, temporary nerve palsy remains very common, imposing a dual physiological and psychological burden on patients. Therefore, exploring safe and effective methods to promote the recovery of recurrent laryngeal nerve function postoperatively is an urgent clinical issue in thyroid surgery. As a motor nerve, the functional recovery of the recurrent laryngeal nerve depends on axonal regeneration and reinnervation of the laryngeal muscles. This process is slow and often incomplete, influenced by factors such as the extent of injury and patient age. Current clinical management of postoperative recurrent laryngeal nerve palsy primarily involves conservative observation and voice training, lacking proactive pharmacological interventions. This presents a clear rationale and clinical entry point for research. Mecobalamin, the active form of vitamin B12, has high bioavailability and directly participates in methylation reactions, as well as nucleic acid and protein synthesis. Studies have confirmed its multifaceted role in treating peripheral neuropathy: (1) It promotes myelin regeneration by enhancing Erk1/2 and Akt activity, accelerating the myelination of damaged nerve fibers; (2) It enhances nerve regeneration by promoting the synthesis and secretion of nerve growth factors; (3) It improves nerve cell metabolism and repairs damaged nerve cell membranes; (4) It exerts neurotrophic effects by stimulating the proliferation and activity of Schwann cells, thereby increasing the secretion of neurotrophic factors and optimizing the microenvironment for nerve regeneration. Although mecobalamin is theoretically beneficial for nerve repair and has been successfully applied in other neuropathies, high-quality clinical studies specifically targeting its use for recurrent laryngeal nerve recovery after thyroid surgery are still lacking. Existing literature consists mostly of small-sample retrospective analyses or case reports with inconsistent conclusions and limitations such as selection bias and inadequate control of confounding factors. There is a lack of large-sample, multicenter, randomized controlled trials to provide high-level evidence-based medical data. Based on this background, the investigators plan to conduct a nationwide multicenter, randomized controlled study. The primary endpoint will be objective acoustic parameters measured by computerized voice analysis, while secondary endpoints will include patient-reported quality of life outcomes, time to voice recovery, subjective patient satisfaction, incidence of permanent paralysis, and adverse drug reactions. The study aims to scientifically and objectively evaluate the efficacy and safety of mecobalamin in promoting the recovery of recurrent laryngeal nerve function after thyroid cancer surgery, providing new therapeutic strategies to optimize perioperative management and improve the quality of life for patients.