Oxidized Regenerated Cellulose and Voice Quality After Total Thyroidectomy

Overview

This randomized controlled trial evaluated whether placement of oxidized regenerated cellulose (ORC) over the recurrent laryngeal nerves during total thyroidectomy affects early postoperative voice quality. Patients undergoing bilateral total thyroidectomy for benign or malignant thyroid disease were assigned in a 1:1 ratio to bilateral placement of ORC within the thyroid bed or to conventional hemostasis without ORC. All participants underwent preoperative videolaryngostroboscopic examination and objective acoustic voice analysis. Acoustic assessment was repeated on postoperative day 21. The study evaluated changes in jitter, shimmer, normalized noise energy, harmonics-to-noise ratio, maximum phonation time, and the s/z ratio. Postoperative complications and adverse events potentially related to ORC were also recorded.

This was a prospective, single-center, randomized, two-arm, parallel-group controlled trial involving patients undergoing bilateral total thyroidectomy for benign or malignant thyroid disease. Before surgery, all participants underwent videolaryngostroboscopic examination to document normal vocal cord mobility and recurrent laryngeal nerve function. Objective acoustic voice analysis was also performed before surgery. All operations were performed by the same experienced endocrine surgeon through a standard Kocher collar incision. Both recurrent laryngeal nerves and the parathyroid glands were routinely identified and preserved. Conventional hemostasis was achieved using bipolar cautery while avoiding thermal injury to the recurrent laryngeal nerves. Immediately before completion of surgery, participants were randomized in a 1:1 ratio using a simple card-drawing method performed by an assistant. In the experimental group, a 1 × 2 cm piece of oxidized regenerated cellulose was placed bilaterally over the recurrent laryngeal nerves within the thyroid bed. In the control group, surgery was completed after conventional hemostasis without placement of oxidized regenerated cellulose. Objective acoustic voice analysis was repeated on postoperative day 21 using 15-second voice recordings analyzed with Dr. Speech Real Analysis software. The assessed acoustic outcomes included jitter, shimmer, normalized noise energy, harmonics-to-noise ratio, maximum phonation time, and the s/z ratio.