Perioperative Analgesia for Thyroid and Parathyroid Surgery: A Review of Current Practices.

This article discusses the algorithms and published practice patterns on perioperative analgesia for thyroid and parathyroid surgery. This includes medications and techniques used for general anesthesia, local anesthesia including nerve block methods, and oral medication used for postoperative pain control. The authors also discuss multimodality pain control and the increased trend to reduce opioid analgesics without inadequate pain control or patient satisfaction.

Rethinking Malignancy Risk in Indeterminate Thyroid Nodules with Positive Molecular Studies: Southern California Permanente Experience.

OBJECTIVES: To recognize that thyroid nodules with atypia of undetermined significance/follicular lesion of undetermined significance (AUS/FLUS; Bethesda III) have different risks of malignancy based on genetic mutation and to consider molecular testing of nodules with AUS/FLUS to help avoid unnecessary morbidity or cost. STUDY DESIGN: Retrospective cohort study. SETTING: Multiple locations within Southern California Permanente Medical Group. SUBJECTS AND METHODS: Patients included those with indeterminate thyroid nodules and AUS/FLUS on 2 separate fine-needle aspirations with positive ThyGenX testing from 2014 to 2017 who underwent thyroid surgery. Patients were classified as having benign or malignant disease. Noninvasive follicular thyroid neoplasm with papillary-like nuclear features was considered benign. RESULTS: A total of 231 patients had repeat AUS/FLUS with positive molecular testing and surgery. The most frequent type of malignancy was papillary carcinoma, followed by follicular carcinoma. The overall prevalence of malignancy in nodules with mutations was 74.0%, although there was considerable variation: BRAF = 100%, RET = 100%, PAX8-PPARγ = 84.6%, HRAS = 70.7%, NRAS = 63.4%, and KRAS = 33%-a statistically significant finding (P < .001). CONCLUSIONS: Not all molecular mutations in thyroid nodules with AUS/FLUS have a high risk of malignancy. Of note, patients with BRAF and RET mutations in our population had a 100% risk of malignancy. Patients with PAX, HRAS, or NRAS mutations had a high risk of malignancy, while patients with KRAS mutations had a lower risk of malignancy. Further studies are needed to determine if the presence of certain molecular mutations can help personalize care and aid in the decision for thyroid surgery.

Hylan B gel restores structure and function to laser-ablated canine vocal folds.

OBJECTIVES: We evaluated cross-linked hyaluronic acid (hylan B gel) as a scaffold for tissue regeneration and mucosal wave restoration in carbon dioxide laser-ablated canine vocal folds. METHODS: Five beagles underwent stroboscopy before ablation of the left vocal fold with a carbon dioxide laser. Four weeks later, stroboscopy was repeated before and after submucosal injection of hylan B gel into the left vocal fold of 4 animals and of saline solution in 1 animal. Stroboscopy was repeated 12 weeks later, and histologic analysis was performed. RESULTS: Four weeks after laser ablation, all animals had soft tissue defects and absence of mucosal waves. Hylan B injection restored mucosal waves, and saline injection did not. Twelve weeks after injection, hylan B-injected larynges had tissue regeneration and mucosal waves, and the saline-injected larynx had neither. Histology showed regenerated lamina propria with residual foci of hylan B in the hylan B-injected larynges and dense submucosal scar in the saline-injected animal. CONCLUSIONS: Submucosal hylan B gel injection in laser-ablated canine vocal folds restored tissue volume and mucosal waves and facilitated functional tissue regeneration over 12 weeks. Hylan B gel may have utility as a soft tissue scaffold for rehabilitation of phonatory function in vocal folds with lamina propria defects.

Injection laryngoplasty with calcium hydroxylapatite gel implant in an in vivo canine model.

The ideal injectable agent for vocal fold medialization is biocompatible, durable, sized to prevent phagocytosis and migration, and formulated for easy injection and does not adversely affect the viscoelastic properties of the vocal fold. We tested a cohesive implant of calcium hydroxylapatite (CaHA) particles in a gel carrier in an in vivo canine model of phonation. Six dogs underwent unilateral recurrent laryngeal nerve section and injection laryngoplasty of the paralyzed vocal fold with a CaHA implant. The six follow-up examinations were performed at 1, 2, 3, 6, 9, and 12 months, and the larynx and bilateral neck lymphatic system were harvested for histologic analysis. The CaHA implant adequately medialized the vocal fold to regain glottal closure. The mucosal waves remained unaltered from baseline. The implant remained soft in the larynx and did not migrate to the neck lymphatic system. A localized foreign body giant cell reaction was present on histologic evaluation, but not acute or other chronic inflammation. A size analysis revealed no resorption of the CaHA particles. A decrease in medialization was noted at all follow-up intervals related to resorption of the aqueous-based gel carrier. The CaHA implant appears to be relatively safe and suitable for injection laryngoplasty.

Local and systemic effects of intralaryngeal injection of cidofovir in a canine model.

OBJECTIVE: The safety of intralaryngeal injection of cidofovir remains a concern. Our goal was to evaluate local and systemic effects of intralaryngeal injection of cidofovir. STUDY DESIGN: Animal study using a canine model. METHODS: Two groups of three young beagle dogs (6 vocal folds in each group) were used. Subepithelial vocal fold injections were performed in each group biweekly for 6 months with 0, 2.5, 5, 10, 20, and 37.5 mg cidofovir in a 0.5 mL volume. Direct laryngoscopy was performed at each injection interval. Complete blood cell count and renal parameters were measured at baseline and monthly thereafter. Histopathologic examination of the vocal folds was performed after the 6-month injection period in one group of animals and after an additional 6-month observation period in the second group. RESULTS: Endomysial edema with muscle fiber separation and dose-dependent atrophy and scarring of the vocal folds was present. Onset of atrophy and scarring was observed after 3, 7, and 11 injections in the vocal folds injected with 37.5, 20, and 10 mg cidofovir, respectively. After the 6-month observation period, recovery of histologic abnormalities was complete in the low-dose (0, 2.5 mg) vocal folds, near complete in the intermediate-dose (5, 10 mg) vocal folds, and no apparent recovery was seen in the high-dose (20, 37.5 mg) vocal folds. Leukocyte count and renal parameters remained unchanged at up to 4.26 mg/kg body weight of systemic dose of cidofovir. CONCLUSIONS: Intralaryngeal cidofovir leads to dose-dependent scarification of the vocal folds that appears irreversible at higher doses. Lower concentrations of this drug should be used in intralesional intralaryngeal use.

Development of a canine model for recurrent respiratory papillomatosis.

A canine model for recurrent respiratory papillomatosis (RRP) was developed with canine oral papillomavirus (COPV) inoculated into the buccal mucosa and supraglottic larynx of 5 beagles. The animals received systemic immunosuppression with daily oral prednisone at doses of 0, 1, 2, 3, and 4 mg/kg. Buccal papillomata developed at 6 weeks in all animals and regressed by 10 weeks in the animals that received 0 and 1 mg/kg. The other animals had continuous growth of their buccal papillomata for 26 weeks. The animal that received 2 mg/kg developed papillomata on the lingual surface of the epiglottis that continued to grow through 26 weeks. Systemic oral prednisone successfully maintained COPV-induced oral and laryngeal papillomata in beagles. Thus, COPV-induced oral and laryngeal papillomata that are prednisone-maintained may have utility as a model for RRP.