RESUMEN
OBJECTIVES: Injury to the external branch of the superior laryngeal nerve (EBSLN) causes low-pitch voice and voice fatigue, particularly in female subjects, and available treatments are limited. Here, we assess a novel surgical procedure to restore a high-tone voice: ansa cervicalis to EBSLN anastomosis (A-E anastomosis). METHODS: Between November 2012 and April 2022, 13 patients (12 female) underwent unilateral EBSLN resection and A-E anastomosis, while 20 (16 female) underwent EBSLN resection during thyroid surgery. Patients (4494 women and 1025 men) with normal laryngoscopy scheduled for thyroid surgery served as normal controls. Phonatory function was examined using a Phonation Analyzer PA-1000 preoperatively and intermittently postoperatively. RESULTS: In patients who underwent A-E anastomosis, high-tone voice pitch decreased significantly postoperatively (673.9-471.5 Hz, p = 0.047), with restoration achieved within 5 months. The mean voice pitch in female patients who underwent A-E anastomosis, EBSLN resection, and controls were 580.4, 522.8, and 682.0 Hz, respectively, indicating a significant decrease in EBSLN resection patients than controls (p = 0.002). The (mean - 1SD) of high-tone voice pitch in female controls was 497 Hz; exceeding this may indicate recovery to a high-tone voice. Overall, 73% (8/11) of A-E anastomosis patients exceeded this value, which was marginally larger than the 43% (6/14) who underwent EBSLN resection. Data on male subjects are limited. There were no cases of adverse functional or cosmetic events. CONCLUSIONS: A-E anastomosis, a novel simple procedure, restored high-tone voice to some extent without any adverse events and thus warrants further investigation. LEVEL OF EVIDENCE: 3 Laryngoscope, 2024.
RESUMEN
Microfluidics is applied in biotechnology research via the creation of microfluidic channels and reaction vessels. Filters are considered to be able to simulate microfluidics. A typical example is the cell culture insert, which comprises two vessels connected by a filter. Cell culture inserts have been used for years to study cell-to-cell communication. These systems generally have a bucket-in-bucket structure and are hereafter referred to as a vertical-type co-culture plate (VTCP). However, VTCPs have several disadvantages, such as the inability to simultaneously observe samples in both containers and the inability of cell-to-cell communication through the filters at high cell densities. In this study, we developed a novel horizontal-type co-culture plate (HTCP) to overcome these disadvantages and confirm its performance. In addition, we clarified the migration characteristics of substances secreted from cells in horizontal co-culture vessels. It is generally assumed that less material is exchanged between the horizontal vessels. However, the extracellular vesicle (EV) transfer was found to be twice as high when using HTCP. Other merits include control of the degree of co-culture via the placement of cells. We believe that this novel HTCP container will facilitate research on cell-to-cell communication in various fields.
RESUMEN
OBJECTIVES: Recurrent laryngeal nerve (RLN) injury is one of the severe complications in thyroid surgery. Therefore, intraoperative nerve monitoring (IONM) has been widely used to identify the RLN and confirm its integrity. Recently, the usefulness of continuous IONM (CIONM) with automatic, periodic stimulation to the vagus nerve during thyroid surgery was reported. This study aimed to report our experience with minimally invasive video-assisted endoscopic endocrine neck surgery (VANS), during which, CIONM was successfully applied for the first time. METHODS: Consecutive patients who underwent thyroid surgery with CIONM, performed in our department using either external neck incision surgery or VANS between July 2017 and June 2019, were retrospectively analyzed. RESULTS: A total of 22 patients who underwent thyroid surgery with neck incision (14 cases; 7 men and 7 women; age, 21-75 years [mean, 52 years]) or VANS (8 cases; 8 women, age, 20-61 years [mean, 41 years]) were enrolled in this study. The addition of CIONM in VANS prolonged the operation's duration by approximately 30 minutes as the endoscopic surgery was technically more difficult. No intra- and postoperative incidence of transient or permanent RLN palsy was observed in any patient, except for three patients who underwent external neck incision surgery in whom combined resection was unavoidable due to tumor invasion of the RLN. CONCLUSION: We reported the first successful application of CIONM during thyroidectomy using VANS. Future clinical trials should clarify the benefits of CIONM when compared to intermittent IONM in VANS. LEVEL OF EVIDENCE: 5.
