Emerging Imaging Technologies for Parathyroid Gland Identification and Vascular Assessment in Thyroid Surgery: A Review From the American Head and Neck Society Endocrine Surgery Section.

Importance: Identification and preservation of parathyroid glands (PGs) remain challenging despite advances in surgical techniques. Considerable morbidity and even mortality result from hypoparathyroidism caused by devascularization or inadvertent removal of PGs. Emerging imaging technologies hold promise to improve identification and preservation of PGs during thyroid surgery. Observation: This narrative review (1) comprehensively reviews PG identification and vascular assessment using near-infrared autofluorescence (NIRAF)-both label free and in combination with indocyanine green-based on a comprehensive literature review and (2) offers a manual for possible implementation these emerging technologies in thyroid surgery. Conclusions and Relevance: Emerging technologies hold promise to improve PG identification and preservation during thyroidectomy. Future research should address variables affecting the degree of fluorescence in NIRAF, standardization of signal quantification, definitions and standardization of parameters of indocyanine green injection that correlate with postoperative PG function, the financial effect of these emerging technologies on near-term and longer-term costs, the adoption learning curve and effect on surgical training, and long-term outcomes of key quality metrics in adequately powered randomized clinical trials evaluating PG preservation.

In-Office Ultrasonographic Evaluation of Neck Masses/Thyroid Nodules.

Office-based ultrasonography is increasingly becoming an integral part of an otolaryngology-head and neck surgery practice. A thorough knowledge of the ultrasonic appearance of normal and abnormal pathology are key for performing/interpreting office-based head and neck ultrasonography. A focused but systematic approach allows for efficient and effective office-based head and neck ultrasonography. Office-based ultrasonography also allows for imaging procedures expanding the otolaryngologist's armamentarium. Ultrasound-guided fine needle aspiration (USgFNA) is an integral part of clinician-performed ultrasonography because it allows cytologic diagnosis of suspicious lesions. Understanding the successful techniques and pitfalls in this procedure are critical for the otolaryngologist performing USgFNA.

Upper neck papillary thyroid cancer (UPTC): A new proposed term for the composite of thyroglossal duct cyst-associated papillary thyroid cancer, pyramidal lobe papillary thyroid cancer, and Delphian node papillary thyroid cancer metastasis.

OBJECTIVES/HYPOTHESIS: Thyroglossal duct cyst (TGDC) is a common congenital anomaly, but TGDC carcinoma is rare. Thyroglossal duct cyst carcinoma management is controversial, especially that of the orthotopic thyroid gland. We aim to provide an insight into the pathologic basis of this management controversy through the review of 28 TGDC cancer cases, thus far the largest such series to our knowledge. STUDY DESIGN: Retrospective. METHODS: Twenty-eight cases recorded as TGDC cancer in the hospital database were reviewed; their initial clinical diagnosis from medical chart review (DX1) and final pathological review diagnosis (DX2) through pathology slides review by our pathologist (blinded to DX1) were compared. The thyroid gland management and pathology were evaluated. RESULTS: In the 28 TGDC carcinoma (hospital-recorded diagnosis) patients, DX1 and DX2 were respectively reported as 53% and 14% TGDC carcinoma, 11% and 29% as pyramidal lobe primary, and 4% and 25% as metastatic Delphian node. Thirty-two percent of cases were in the indeterminate category, in both DX1 and DX2, but included different patients. Thyroidectomy was performed in 54% of the cases, papillary thyroid cancer (PTC) was reported in 37% of these thyroid glands. Concurrent thyroid gland malignancy was reported in all Delphian node and pyramidal lobe PTC patients. CONCLUSION: The diagnosis of TGDC cancer comprises a heterogeneous group that includes true TGDC cancer, pyramidal lobe primary, Delphian node metastasis, and indeterminate cases. We propose a new terminology of upper neck papillary thyroid carcinoma (UPTC) to denote this heterogeneous group and recommend a rational algorithm for management. Correct pathologic subcategory and thyroid ultrasonography are essential for optimal management of thyroid gland in UPTC cases. LEVEL OF EVIDENCE: 4. Laryngoscope, 126:1709-1714, 2016.

Normative intra-operative electrophysiologic waveform analysis of superior laryngeal nerve external branch and recurrent laryngeal nerve in patients undergoing thyroid surgery.

BACKGROUND: Injury to the external branch of the superior laryngeal nerve (EBSLN) can occur during superior pole dissection in thyroid surgery; the EBSLN injury rate is reported as high as 28 % (Cernea et al., Head Neck 14:380-383, 1992). Injury to the EBSLN leads to variable symptoms that may be overlooked, but that can be significant, especially to professional speakers and singers. Intraoperative nerve monitoring (IONM) is employed widely to aid in nerve identification. We report on normative electroneuromyography (EMG) data on EBSLN-IONM and cricothyroid muscle (CTM) twitch response during stimulation as an aid to EBSLN identification. METHODS: A prospective study of the SLN and the recurrent laryngeal nerve (RLN) IONM data in 72 consecutive thyroid surgeries was carried out. All patients underwent preoperative and postoperative laryngeal exams, and patients with abnormal preoperative laryngeal function were excluded. Normative EMG data and CTM twitch response during EBSLN stimulation were recorded and analyzed. RESULTS: Stimulation of the EBSLN resulted in a positive CTM twitch response in 100 %, whereas EMG response was recordable in 80 %. Electromyographic amplitude was ~1/3 of ipsilateral RLN amplitude and did not change through the case with multiple stimulations. Stimulation of the EBSLN was similar for men and women and at 1 and 2 mA stimulation levels. CONCLUSIONS: Intraoperative nerve monitoring of the EBSLN aids in EBSLN identification and provides electroneuromyographic information in 80 % of cases. The laryngeal head of the sternothyroid muscle is a useful landmark to locate EBSLN.

Fibular free flaps in the management of osteomyelitis of the mandible.

BACKGROUND: Fibular free flaps are an alternative method in the management of chronic osteomyelitis of the mandible without osteoradionecrosis. METHODS: A prospective review of 2 cases of chronic osteomyelitis of the mandible managed with a fibular free flap was conducted. Patient satisfaction and aesthetic results were examined. Follow-up to 9 months was achieved and radiographic studies conducted. The current literature on the treatment of chronic osteomyelitis of the mandible and the use of free flaps in its management was reviewed. RESULTS: The 2 patients with chronic osteomyelitis of the mandible whose conservative management failed were effectively treated with the use of a fibular free flap reconstruction. CONCLUSION: Microvascular reconstruction with a fibular free flap should be considered as a treatment option in the management of chronic osteomyelitis of the mandible.

Workup of well-differentiated thyroid carcinoma.

BACKGROUND: Well-differentiated thyroid carcinoma (WDTC) includes three main entities: papillary thyroid carcinoma (PTC), follicular thyroid carcinoma (FTC), and Hurthle cell carcinoma (HCC). A thorough knowledge of the natural history and presentation of these carcinomas is vital to the thyroid surgeon. METHODS: This review details the preoperative workup of patients having or suspected to have WDTC. We review the history, physical examination, laboratory, and radiographic evaluations that optimally prepare the surgeon to determine the ideal surgical thyroid and neck treatment for patients with WDTC. RESULTS: A fiberoptic evaluation of the larynx is integral to the physical examination, and a laryngeal assessment is performed for all patients who will undergo thyroid surgery. It must be noted that vocal cord paralysis can be subtle and does not always present with clear dysphagia or voice change. Ultrasound and FNA are the primary tools of preoperative assessment. Given that patients with preoperative FNA positive for papillary cancer are expected to have clinically significant nodal disease in one third of cases, radiographic evaluation must be appropriately aggressive. The combination of US and CT allows assessment of the central and lateral neck nodes and the thyroid's relationship to central neck viscera. CONCLUSIONS: The overriding principle in the surgical treatment of WDTC is that the surgeon recognizes and encompasses all gross disease in the thyroid and neck nodes at first surgery. The extent of thyroidectomy is tailored not only to the patient's risk group and gross operative findings but also to the progress of the specific surgery in terms of parathyroid and recurrent laryngeal nerve preservation.