The relation of recurrent laryngeal nerve to inferior thyroid artery and extralaryngeal nerve branching may increase the risk of vocal cord paralysis in thyroidectomy.

PURPOSE: The anatomical variations of the recurrent laryngeal nerve (RLN) are common during thyroidectomy. We aimed to evaluate the risk of RLN paralysis in case of its anatomical variations, retrospectively. METHODS: The patients with primary thyroidectomy between January 2016 and December 2019 were enrolled. The effect of age, gender, surgical intervention, neuromonitorisation type, central neck dissection, postoperative diagnosis, neck side, extralaryngeal branching, non-RLN, relation of RLN to inferior thyroid artery (ITA), grade of Zuckerkandl tubercle on vocal cord paralysis (VCP) were investigated. RESULTS: This study enrolled 1070 neck sides. The extralaryngeal branching rate was 35.5%. 45.9% of RLNs were anterior and 44.5% were posterior to the ITA, and 9.6% were crossing between the branches of the ITA. The rate of total VCP was 4.8% (transient:4.5%, permanent: 0.3%). The rates of total and transient VCP were significantly higher in extralaryngeal branching nerves compared to nonbranching nerves (6.8% vs. 3.6%, p = 0.018; 6.8% vs. 3.2%, p = 0.006, respectively). Total VCP rates were 7.2%, 2.5%, and 2.9% in case of the RLN crossing anterior, posterior and between the branches of ITA, respectively (p = 0.003). The difference was also significant regarding the transient VCP rates (p = 0.004). Anterior crossing pattern increased the total and transient VCP rates 2.8 and 2.9 times, respectively. CONCLUSION: RLN crossing ITA anteriorly and RLN branching are frequent anatomical variations increasing the risk of VCP in thyroidectomy that cannot be predicted preoperatively. This study is the first one reporting that the relationship between RLN and ITA increased the risk of VCP.

A unique complication of thyroidectomy for Hashimoto's thyroiditis: central retinal artery thrombosis.

BACKGROUND: Central retinal artery occlusion (CRAO) is a rare ophthalmological emergency and also a unique complication after thyroid surgery. METHODS: We present the first case of CRAO following thyroid surgery in a patient with Hashimoto's thyroiditis, along with a variety of interventions to overcome this complication. RESULTS: A 42-year-old female patient suffering from sudden vision loss following total thyroidectomy was diagnosed with CRAO. Hyperbaric oxygen therapy was started within the postoperative first 6 hours. CONCLUSION: Although it is extremely rare, it should be noted that patients may experience retinal artery occlusion following the thyroid surgery. Immediate evaluation of patients with visual impairment in the early postoperative period, and planning of emergent hyperbaric oxygen therapy for the management are critical.

Intraoperative cricothyroid muscle electromyography may contribute to the monitorization of the external branch of the superior laryngeal nerve during thyroidectomy.

Background: In thyroid surgery, both the recurrent laryngeal nerve (RLN) and external branch of the superior laryngeal nerve (EBSLN) should be preserved for maintaining the vocal cord functions. We aimed to evaluate whether EMG of the CTM applied after the superior pole dissection provided additional informative data to the IONM via ETT or not, regarding the EBSLN function. Methods: The prospectively collected data of the patients, who have undergone thyroidectomy with the use of IONM for the exploration of both the RLN and EBSLN between October 2016 and March 2017, were evaluated retrospectively. Patients over 18 years of age with primary thyroid surgery for malignant or benign thyroid disease, and whom were applied CTM EMG with a needle electrode after the completion of thyroidectomy were included in the study. In the study, each neck side was evaluated as a separate entity considering the EBSLN at risk. Results: The data of 41 patients (32 female, 9 male) (mean age, 46.7 + 9.1; range, 22-71) were evaluated. Sixty seven EBSLNs out of 26 bilateral and 15 unilateral interventions were evaluated. With EBSLN stimulation after the superior pole dissection, positive glottic EMG waveforms via ETT were obtained in 45 (67.2%) out of 67, and the mean glottic amplitude value was 261 + 191 µV (min-max: 116-1086 µV). Positive EMG responses via the CTM EMG were achieved from all of the 67 EBSLNs (100%) with stimulation using a monopolar probe at the most cranial portion above the area of divided superior pole vessels. The mean value of CTM amplitudes via CTM EMG obtained with EBSLN stimulation was 5268 + 3916 µV (min-max:1215 -19726 µV). With EBSLN stimulation, the mean CTM EMG amplitude was detected significantly higher than the mean vocal cord amplitude (p<0.0001). The CTM EMG provided more objective quantifiable data regarding the EBSLN function (100% vs 67,2%, p<0.001). Conclusion: In addition to the IONM via ETT, intraoperative post-dissection CTM EMG via needle electrode is a safe, simple and applicable method that may provide significant additional informative data to IONM with ETT by obtaining and recording objective quantitative data related to the EBSLN function.

Comparison of transoral endoscopic thyroidectomy vestibular approach and open conventional thyroidectomy regarding inflammatory responses, pain, and patient satisfaction: a prospective study.

Introduction: The application of transoral endoscopic thyroidectomy vestibular approach (TOETVA) is becoming widespread throughout the world. We primarily aimed to evaluate the severity of surgical trauma in TOETVA and conventional open thyroidectomy (COT) regarding the inflammatory response including the comparison of surgical stress markers [interleukin-6 (IL-6), C-reactive protein (CRP), white blood cell (WBC)]. Material and method: This non-randomized prospective study enrolled two groups with 20 patients each: COT group and TOETVA group. Patients aged 18-65 years with benign thyroid disease; with fine needle aspiration biopsy results of Bethesda III, IV or Bethesda V, VI (<1 cm nodule); thyroid volume <50 cm3; nodule diameter <4 cm; female gender without a previous neck, chin, and/or oral surgery; without vocal cord paralysis preoperatively; and patients in euthyroid state were enrolled to the study. Preoperative, postoperative second hour, first day, and second day CRP, WBC, and IL-6 levels were evaluated. Pain intensity was evaluated with the visual analog scale (VAS) score on the 2nd and 12th hour, 1st and 2nd days postoperatively. Results: All the patients were female and mean age was significantly higher in the COT group. The operative time was significantly longer in the TOETVA group. No significant difference was found between the two groups regarding IL-6 levels. In the TOETVA group, postoperative second hour WBC value (p = 0.044) and first (p = 0.002) and second day (p = 0.005) CRP values were significantly higher. In the TOETVA group, the lower lip and lower chin VAS scores were significantly higher at 2nd and 12th hour, on the first and second days. The anterior neck VAS score was significantly higher in the TOETVA group at the second hour (p = 0.025). General and cosmetic satisfactions were similar at the 15th and 30th days in both groups. Conclusion: The longer operative time and higher postoperative CRP level and VAS score in the chin and lower lip in the TOETVA group suggested that the method is not a minimally invasive technique compared to COT. However, the presence of similar total complication rates and early postoperative general and esthetic satisfaction that improves over time in both groups suggests that the clinical effect of increased magnitude of systemic inflammatory response in TOETVA might be temporary and acceptable.

The Role of 4D-CT for Pre-Operative Localization in Patients with Primary Hyperparathyroidism with Negative Ultrasonography and/or Sestamibi SPECT/CT.

Objectives: The major cause of primary hyperparathyroidism (pHPT) is parathyroid adenoma. Today, minimally invasive parathyroidectomy (MIP) has become the standard treatment for patients in whom the pathological gland can be localized with pre-operative imaging methods. In this study, we aimed to evaluate the role of 4D-CT in pre-operative localization in patients with pHPT who are negative for ultrasonography (USG) and/or sestamibi single-photon emission computed tomography/CT (SPECT/CT) and will undergo primary surgery. Methods: Patients whom were operated between 2018 and 2023 were included to this study. 4D-CT results of patients with one- or two-negative USG and SPECT/CT results were evaluated retrospectively. Results: In this study, 19 patients (5 men and 14 women) with a mean age of 57.1±8.5 years were evaluated. Pathology results were consistent with parathyroid adenoma in 18 patients (94.7%) and parathyroid hyperplasia in 1 patient (5.3%). USG was negative in six patients, SPECT/CT was negative in 14 patients, and both were negative in four patients. In 4D-CT, positive images were detected in 15 patients and these results were finalized as true positive in 14 patients and false positive in 1 patient. The sensitivity of 4D-CT was 82.4% (95% CI: 60.4-95.3%), positive predictive value was 93.3% (95% CI: 73.8-99.6%), accuracy was 78.9%, and localization rate was 73.7%. In 14 (73.7%) patients, the pathological glands were removed by MIP. Conclusion: In approximately 75% of patients with negative USG and/or SPECT/CT, the pathological gland can be localized with 4D-CT and MIP can be applied in these patients.

Persistent and Recurrent Primary Hyperparathyroidism: Intraoperative Supplemental Methods, Basic Principles of Surgery, and Other Treatment Options.

Reoperative parathyroid surgery is challenging even for experienced surgeons. Cure rates are lower than primary surgery. Good anatomical and embryological knowledge is important. Preoperatively, a comprehensive surgical strategy should be planned. Pre-operative imaging modalities should be used extensively to find the overlooked gland to have a possibility to perform focused parathyroid surgery to avoid possible complications. One of the important developments is the new ancillary methods to find overlooked parathyroid glands. Orthotopic and possible ectopic locations should be known well by the surgeon to increase the surgical success rate. Reoperative parathyroid surgery needs a distinctive approach compared to primary parathyroid surgery. Basic principles include the selection of the incision and route for entering the thyroid region, use of ancillary methods, and intraoperative nerve monitoring and also require a meticulous dissection. Obtaining a surgical cure is difficult and high surgical caution is needed. Post-operative complication rates are higher compared to primary parathyroid surgery. Other treatment methods and medical treatment options may be evaluated in a patient who cannot undergo surgery.

Predictive Factors Affecting the Development of Lateral Lymph Node Metastasis in Papillary Thyroid Cancer.

Objectives: Lateral lymph node metastasis (LLNM) in papillary thyroid cancer (PTC) determines the extent of surgery to be performed and the prognosis of the disease. In this study, we aimed to evaluate the clinicopathological risk factors affecting the development of LLNM. Methods: We retrospectively evaluated the demographic and clinicopathological data of 346 cases with PTC who were operated in our clinic between May 2012 and September 2020. The patients were divided into 2 groups as patients with LLNM (Group 1) and without LLNM (Group 2). Results: Thirty-six (10.4%) patients out of 346 patients with PTC had LLNM. A statistically significant difference was found between Group 1 and Group 2 regarding the male gender (M/F: 38.9% vs. 21.6%; p=0.020), tumor size (2.30±1.99 cm vs. 1.31±1.40 cm; p=0.000), lymphovascular invasion (69.4 vs. 20.6%; p=0.000), multicentricity (69.4% vs. 35.5%; p=0.000), multifocality (p=0.000), aggressive variant (22.2% vs. 9.4%; p=0.000), extrathyroidal extension (50% vs. 16.1% p=0.000), central lymph node metastasis (CLNM) rates (75% vs. 6.5%; p=0.000), and ≥3 cm lymph node metastasis (48.5% vs. 0%, p=0.000), distant metastasis (2.1% vs. 0%, p=0.000), respectively. Multivariance analysis determined the presence of CLNM as an independent risk factor for the development of LLNM. Conclusion: The presence of CLNM in patients with PTC was determined as an independent risk factor for the development of LLNM. Although there has been increasing debate about prophylactic central neck dissection (pCND) in LLNM, pCND should still be considered in these patients as the rate of CLNM is high in patients with LLNM. CLNM might be a reference for surgeons to determine the extent of surgery. In addition, the presence of CLNM is important for close follow-up for the early detection of LLNM recurrence.

Management of Thyroid Nodules.

Thyroid nodules are common and the prevalence varies between 4 and 7% by palpation and 19-68% by high-resolution USG. Most thyroid nodules are benign, and the malignancy rate varies between 7 and 15% of patients. Thyroid nodules are detected incidentally during clinical examination or, more often, during imaging studies performed for another reason. All detected thyroid nodules should be evaluated clinically. The main test in evaluating thyroid function is thyroid stimulating hormone (TSH). If the serum TSH level is below the normal reference range, a radionuclide thyroid scan should be performed to determine whether the nodule is hyperfunctioning. If the serum TSH level is normal or high, ultrasonography (US) should be performed to evaluate the nodule. US is the most sensitive imaging method in the evaluation of thyroid nodules. Computed tomography (CT) and magnetic resonance imaging are not routinely used in the initial evaluation of thyroid nodules. There are many risk classification systems according to the USG characteristics of thyroid nodules, and the most widely used in clinical practice are the American Thyroid Association guideline and the American College of Radiology Thyroid Imaging Reporting and Data System. Fine needle aspiration biopsy (FNAB) is the gold standard method in the evaluation of nodules with indication according to USG risk class. In the cytological evaluation of FNAB, the Bethesda System for Reporting Thyroid Cytopathology (TBSRTC) is the most frequently applied cytological classification. TBSRTC is a simplified, 6-category reporting system and was updated in 2023. The application of molecular tests to FNAB specimens, especially those diagnosed with Bethesda III and IV, is increasing to reduce the need for diagnostic surgery. Especially in Bethesda III and IV nodules, different methods are applied in the treatment of nodules according to the malignancy risk of each category, these are follow-up, surgical treatment, radioactive iodine treatment, and non-surgical ablation methods.

An unusual finding after adrenal surgery: a case series of adrenal schwannomas.

Adrenal schwannomas are rare benign tumors with no specific imaging and laboratory findings to diagnose preoperatively. Due to the limited number of cases in the literature, clinical, imaging, and pathological findings are presented in this study. Case 1 is a 61-year-old woman patient who has a 31-mm mass in the right adrenal gland. This mass was nonfunctional; in imaging studies, this mass had a cystic necrotic component, and high 18-fluorodeoxyglucose (FDG) uptake was seen. There was no metaiodobenzylguanidine (MIBG) uptake. Laparoscopic transabdominal right adrenalectomy was performed, and the pathology result was consistent with adrenal schwannomas. Case 2 is a 63-year-old man patient who presented with a 38-mm mass in the left adrenal gland. This mass was nonfunctional and similar to that in Case 1; this mass had a cystic component. Laparoscopic transabdominal left adrenalectomy was performed. The diagnosis of adrenal schwannoma with degeneration was revealed. Case 3 was a 72-year-old woman patient admitted to the hospital for a 125-mm left adrenal mass. Similar to Case 1, this mass also had a cystic necrotic component in imaging studies. High FDG uptake was seen, and the patient underwent conventional adrenalectomy due to the suspicion of malignancy. After pathological evaluation, a diagnosis of adrenal schwannoma was made. A main diagnostic challenge in adrenal schwannomas is the preoperative diagnosis. These masses have no pathognomonic finding or specific hormonal function. Imaging findings of these masses may increase the suspicion of malignancy, which may affect decisions for surgery and the surgical technique.

Persistent and Recurrent Primary Hyperparathyroidism: Etiological Factors and Pre-Operative Evaluation.

Primary hyperparathyroidism (pHPT) is the most common cause of hypercalcemia and currently the only definitive treatment is surgery. Although the success rate of parathyroidectomy is over 95% in experienced centers, surgical failure is the most common complication today. Persistent HPT (perHPT) is defined as persistence of hypercalcemia after parathyroidectomy or recurrence of hypercalcemia within the first 6 months, and recurrence of hypercalcemia after a normocalcemic period of more than 6 months is defined as recurrent HPT (recHPT). In the literature, perHPT is reported to be 2-22%, and the rate of recHPT is 1-15%. perHPT is often associated with misdiagnosed pathology or inadequate resection of hyperfunctioning parathyroid tissue, recHPT is associated with newly developing pathology from potentially pathologically natural tissue left in situ at the initial surgery. In the pre-operative evaluation, the initial diagnosis of pHPT and the diagnosis of perHPT or rec HPT should be confirmed in patients who are evaluated with a pre-diagnosis (suspect) of perHPT and recHPT. Surgery is recommended if it meets any of the recommendations in surgical guidelines, as in patients with pHPT, and there are no surgical contraindications. The first preoperative localization studies, surgical notes, operation drawings, if any, intraoperative PTH results, pathological results, and post-operative biochemical results of these patients should be examined. Localization studies with preoperative imaging methods should be performed in all patients with perHPT and recHPT with a confirmed diagnosis and surgical indication. The first-stage imaging methods are ultrasonography and Tc99m sestamibi single photon tomography Tc99mMIBI SPECT or hybrid imaging method, which is combined with both single-photon emission computed tomography and computed tomography (SPECT/CT). The combination of USG and sestamibi scintigraphy increases the localization of the pathological gland. In the secondary stage, Four-Dimensional computer tomography (4D-CT) or dynamic 4-dimensional Magnetic Resonance Imaging (4D-MRI) can be applied. It is focused on as a secondary stage imaging method, especially when the lesion cannot be detected by conventional methods. Positron Emission Tomography (PET) and PET/CT examinations with 11C-choline or 18F-fluorocholine are promising imaging modalities. Invasive examinations can rarely be performed in patients in whom suspicious, incompatible or pathological lesion cannot be detected in noninvasive imaging methods. Bilateral jugular vein sampling, selective venous sampling, parathyroid arteriography, imaging-guided fine-needle aspiration biopsy, and parathormone washout are invasive methods.

The Relationship of Negative Imaging Result and Surgical Success Rate in Primary Hyperparathyroidism.

Objectives: In present, the effect of pre-operative negative imaging results on surgical outcomes of primary hyperparathyroidism (pHPT) is still controversial. In this study, we aimed to evaluate the effect of pre-operative imaging on surgical outcomes. Methods: The data of pHPT patients who were operated between 2009 and 2018 were evaluated retrospectively. Patients were divided three groups according to scintigraphy and/or ultrasonography results: Group 1; both imaging positive, Group 2; single imaging positive, and Group 3; patients in whom both imaging modalities are negative. Pre-operative biochemical characteristics, parathyroid pathologies, diameter and volume of the pathological gland, surgery rates, persistence, and recurrent disease rates of the groups were compared. Results: Of 311 patients (258F, 53M) with a mean follow-up period of 24.7±18 months and a mean age of 54.1±12.9 years; 161 were in Group 1, 111 were in Group 2, and 39 were in Group 3. The diameter of pathological gland (2.1±0.8, 1.6±0.9, 1.5±0.7 cm; p<0.001; in Group 1,2,3 respectively) and the volume of pathological gland (2±3.2, 1.4±2.9, 1.1±2.2 cm3; p<0.001; in Group 1,2,3, respectively) in Group 1; the rate of multi gland disease (5.7%, 11%, 21%; p=0.024; in Group 1, 2, 3, respectively) in Group 3 were significantly higher. In the 1, 2, 3 group; bilateral exploration rates were 93.2%, 48.6%, and 5.1%, and focused surgery or unilateral exploration rates were 6.8%, 51.4%, and 94.9%, respectively, with a significant difference (p<0.001). After the first surgery, the cure rate was 91.3%, 93.7%, and 89.7%, and the persistent patient rate was 7.5%, 3.6%, and 10.3% in Groups 1,2,3, respectively, and there was no significant difference. At the end of the follow-up period after secondary intervention applied in persistent and recurrent patients, the overall cure rate was 97.4%, 96.4%, and 97.4%, persistent disease rate 1.3%, 1.8%, and 2.6%, recurrent disease rate 1.3%, 1.8%, and 0%, respectively. Conclusion: In imaging-negative patients with pHPT, the possibility of multi gland disease and smaller pathological glands should be considered at the time of surgery. Surgery in imaging-negative patients can be performed with a similar and acceptable cure rate to imaging-positive patients.

The Role of Frozen Section Examination in Thyroid Surgery.

In endocrine pathology, frozen section (FS) examination is most commonly used for the intraoperative evaluation of thyroid and parathyroid tumors, as well as cervical lymph nodes. In the past, frozen section was considered a fundamental tool in thyroid surgery. However, with advancements in preoperative ultrasound and fine-needle aspiration biopsy (FNAB), there have been increasing queries about its routine use due to the improved preoperative diagnosis. Nowadays, while the use of FS during thyroidectomy has decreased, it is still used as an additional method for different purposes intraoperatively. FS may not always provide definitive results. If FS will alter the surgical plan or extent, it should be applied. Routine FS is not recommended for evaluating thyroid nodules. But in addition to FNAB, if FS results may change the operation plan or extent, they can be utilized. FS should not be applied for thyroid lesions smaller than 1 cm, and the entire lesion should not be frozen for FS. For the assessment of thyroid nodules, the use of FS is recommended based on the Bethesda categories of FNAB. In Bethesda I category nodules, FS may contribute to distinguishing between malignant and benign lesions and guide surgical treatment. In Bethesda II nodules, where the malignancy rate is low, the performance of FNAB and FS can be compared, but it's not recommended due to the lack of a significant contribution to the surgical strategy. The sensitivity of FS in Bethesda III and IV nodules is low; its contribution to the diagnosis is limited, and it does not provide an apparent benefit to treatment; therefore, it is not recommended. In Bethesda V nodules, FS can effectively confirm the malignancy diagnosis, contribute to the surgical strategy, and reduce the possibility of completion thyroidectomy, and accordingly, it is recommended for use. Nonetheless, in Bethesda V nodules with a benign FS report, the malignancy rate remains high, so it should not be used to rule out malignancy. In Bethesda VI nodules, the performance of FS is lower or comparable to FNAB and does not significantly contribute to the treatment strategy; hence, it is not recommended. Particularly in patients with papillary thyroid cancer, intraoperative FS can be effective in detecting extrathyroidal extension and can assist the surgeon in determining the extent of thyroid surgery and central neck dissection. FS has high sensitivity and specificity in evaluating the lymphatic status of the central region intraoperatively and can be used to determine the extent of central compartment node dissection. During thyroidectomy, FS examination can be used in recognizing parathyroid tissue and distinguishing it from fatty tissue, thymus, thyroid, lymph nodes, especially in differentiating metastatic lymph nodes.

Can Unilateral Therapeutic Central Lymph Node Dissection Be Performed in Papillary Thyroid Cancer with Lateral Neck Metastasis?

Objectives: Unilateral or bilateral prophylactic central neck dissection (CND) in papillary thyroid cancer (PTC) is still controversial. We aimed to evaluate the risk factors for contralateral paratracheal lymph node metastasis and whether CND might be performed unilaterally. Methods: Prospectively collected data of patients who underwent bilateral CND and lateral neck dissection (LND) with thyroidectomy due to PTC with lateral metastases, between January 2012 and November 2019, were evaluated retrospectively. The patients were divided into two groups according to the presence (Group 1) and absence (Group 2) of metastasis in the contralateral paratracheal region.A total of 42 patients (46 ±15.7 years) were operated. In the contralateral paratracheal region, Group 1 (35.7%) had metastases, while Group 2 (64.3%) had no metastases. In groups 1 and 2, metastasis rates were 100% vs 77.8% (p=0.073), 46.7% vs 18.5% (p=0.078), and 80% vs 40.7% (p=0.023) for the ipsilateralparatracheal, prelaryngeal and pretracheal lymph nodes, respectively.The number of metastatic lymph nodes in the central region was significantly higher in Group 1 compared to Group 2 as; 10.7±8.4 vs. 2.6±2.4 (p=0.001) in bilateral central region material; 8.3±7.4 vs. 2.9±2.7 (p=0.001) in lateral metastasis with ipsilateral unilateral central region; 3.8±3.4 vs. 1.9±1.9 (p=0.023) in ipsilateralparatracheal area; and 3.7±4.6 vs. 0.6±0.9 (p=0.001) in pretracheal region, respectively. However, no significant difference was found regarding the prelaryngeal region material (0.9±1.8 vs. 0.2±0.4 (p=0.71)). Results: >2 metastatic central lymph nodes in unilateral CND material (AUC: 0.814, p<0.001, J=0.563) can estimate contralateral paratracheal metastasis with 93% sensitivity, 63% specificity, while >2 pretracheal metastatic lymph nodes (AUC: 0.795, p<0.001, J: 0.563) can estimate contralateral paratracheal metastasis with 60% sensitivity and 96.3% specificity. Conclusion: In patients with lateral metastases, the rate of ipsilateralparatracheal metastasis is 85%, while the rate of contralateral paratracheal metastasis is 35.7%. The number of ipsilateral central region or pretracheal lymph node metastases may be helpful in predicting contralateral paratracheal lymph node metastases. Notably, unilateral CND may be performed in the presence of ≤ 2 metastases in the ipsilateral central region.

The relationship of pre-operative vitamin D and TSH levels with papillary thyroid cancer.

OBJECTIVE: Our goal in this study is to analyze the correlation between papillary thyroid cancer (PTC) with elevated thyroid-stimulating hormone (TSH) levels and deficiency of vitamin D. METHODS: Patients who underwent thyroidectomy, also with available vitamin D test results preoperatively, were included in the study. The patients were separated into two different categories as having papillary thyroid carcinoma (Group 1), benign diseases (Group 2). According to the TSH (mUI/mL) level and vitamin D values, patients were categorized into four quarters. RESULTS: Preoperatively, TSH level (mean±SDmUI/mL) was higher in Group 1 (2.04±1.55) compared to Group 2 (1.82±1.94) significantly (p=0.029). Preoperatively, vitamin D levels (mean±SD) were higher in Group 1 (15.88±10.88) than in Group 2 (12.94±10.26) significantly (p=0.011). There was no significant difference between Group 1 and Group 2 according to the vitamin D deficiency (65.5%, 72.8%; respectively (p=0.472)). When categorized with reference to pre-operative vitamin D levels, the proportion of patients in Group 2 and Category 1 was higher significantly (p=0.031). CONCLUSION: Although the pre-operative TSH level was significantly higher in papillary thyroid carcinoma than benign thyroid diseases, the categorical distributions of the patients according to the TSH value were similar and the TSH values overlapped. Pre-operative mean vitamin D levels were similar in both PTC and benign thyroid disease groups so PTC was not associated with vitamin D deficiency.

Contribution of intraoperative parathyroid hormone monitoring to the surgical success in minimal invasive parathyroidectomy.

Background: The contribution of intraoperative parathyroid hormone monitoring to minimally invasive parathyroidectomy remains controversial. We aimed to evaluate whether intraoperative parathyroid hormone monitoring monitoring could contribute to minimally invasive parathyroidectomy in these patients. Methods: The data of the patients whose preoperative ultrasonography and technetium-99 m sestamibi scintigraphy imagings were positive and concordant for one gland and who underwent minimally invasive parathyroidectomy between 2003 and 2018 in our clinic, were evaluated retrospectively. Blood samples were collected at pre-excisional period, and at post-excisional 10 and 20 min; the intaoperative parathyroid hormone was measured, and the surgery was terminated without waiting for the result. Patients were divided into 2 groups according to the postoperative results, as those with normocalcemia (Group 1) and those with persistence (Group 2). Results: There were 195 patients in Group 1 and 14 patients in Group 2. The cure rate at the first surgery was 93.3%. Cure was achieved after the second operation in all patients in Group 2. Recurrent disease developed in 1 patient in group 1 and the overall cure rate was 99.5%. If intraoperative parathyroid hormone had been evaluated, cure could have been achieved at the first surgery with additional exploration, in 10 (71.4%) of 14 patients according to the insufficient decrease in parathyroid hormone value at the 10 min in Group 2, and in 9 (64.3%) of 14 patients according to the parathyroid hormone value at 20 min. However, due to insufficient decrease (false negative) in the parathyroid hormone value at the 10 and 20 min the rate of false negatives and unnecessary exploration would be 9.5% and 2.5%, respectively. With additional exploration, the cure rate in the first surgery could be increased by 4.3%-97.6% according to the 20 min intraoperative parathyroid hormone value. Conclusion: The cure rate in minimally invasive parathyroidectomy can be increased by minimizing unnecessary conversion to bilateral neck exploration, by evaluating intraoperative parathyroid hormone at 10 min in patients with positive and concordant scans, and intraoperative parathyroid hormone at 20 min in patients with inadequate decrease at 10 min intraoperative parathyroid hormone.

Is craniocaudal dissection of recurrent laryngeal nerve safer than lateral approach: a prospective randomized study comparing both techniques by using continuous intraoperative nerve monitoring.

Purpose: This study was performed to compare the real-time electromyographic (EMG) changes and the rate of recurrent laryngeal nerve (RLN) injury in craniocaudal and lateral approaches for RLN during thyroidectomy. Methods: One hundred twelve and 86 patients were prospectively randomized to receive lateral (group 1) or craniocaudal (group 2) approach to RLN, respectively, under continuous intraoperative nerve monitoring. Results: Loss of signal (LOS) occurred in 7 (2.0%) of 356 nerves at risk (NAR). LOS was significantly associated with repeated adverse EMG changes and presence of RLN entrapment at the ligament of Berry (LOB), which was accompanied by other clinicopathological or anatomical features, such as tubercle of Zuckerkandl (TZ), extralaryngeal branching, hyperthyroidism, autoimmune thyroid disease (ATD), or thyroid lobe volume of >29 cm3 (P = 0.001 and P = 0.030, respectively). The rate of repeated adverse EMG changes and LOS in the NARs with LOB entrapment accompanied by other clinicopathological and anatomical features was higher in group 1 vs. group 2 (11.1% vs. 2.2%, respectively and 9.7% vs. 0%, respectively; P = 0.070). The total rate of vocal cord palsy (VCP) was significantly higher in group 1 than in group 2 (P = 0.005). The rate of permanent VCP showed no significant difference between the 2 groups. Conclusion: The craniocaudal approach to the RLN is safer than the lateral approach in the RLNs with entrapment at the LOB accompanied by other features, such as TZ, extralaryngeal branching, hyperthyroidism, ATD, or high thyroid lobe volume.

Predictive Factors Affecting the Development of Central Lymph Node Metastasis in Papillary Thyroid Cancer.

Objectives: The most common subtype of thyroid cancer is papillary thyroid cancer (PTC); lymph node metastases are common in this disease. Factors affecting the development of central lymph metastasis of PTC determine the treatment modality and prognosis of the disease. In this study, we aimed to evaluate the clinicopathologic features affecting the development of central lymph node metastasis. Methods: The data of a total of 346 PTC patients who were operated between May 2012 and September 2020 in our clinic and whose follow-up could be reached were evaluated retrospectively. Demographic data, surgical treatment modalities, and histopathological data of all patients were evaluated as a result of at least 6 months of follow-up. Patients age, sex, body mass index, pre-operative TSH levels, anti-TPO, and anti-Tg values at the time of diagnosis, whether lymph node dissection is performed, presence of lymph node metastasis, presence of distant metastasis, stage at the time of diagnosis (TNM 8th edition), ATA risk group at the time of diagnosis, multifocal and/or multicentric (bilaterality), largest tumor size, aggressive histological subtype, lymphovascular invasion of the tumor, extrathyroidal invasion, presence of lymphocytic thyroiditis, and surgical margin positivity were evaluated retrospectively. Results: In the development of PTC central metastasis, distant metastasis, tumor size, multifocality, multicentricity, presence of lymphovascular invasion, aggressive tumor subtype, presence of lateral metastasis, nodular goiter, and extrathyroidal spread were found to be effective. Among these factors, T stage, presence of lymphovascular invasion, and multicentricity were identified as independent risk factors for the development of central metastasis. Conclusion: Today, the investigation of predictive factors for the development of nodal metastasis in PTC does not seem to be out of date anytime soon. In our study, T stage, presence of lymphovascular invasion, and multicentricity were identified as independent risk factors for the development of central metastasis from the histopathological features of the tumor in PTC and of these features, T stage and multicentricity can be predicted by pre-operative imaging in many patients and can be used to decide whether to perform prophylactic SLN dissection in patients. However, new studies are still needed on this issue, in the literature.

Surgical Treatment of Substernal Goiter Part 1: Surgical Indications, Pre-Operative, and Peroperative Preparation.

Surgery is one of the most appropriate treatment options for many patients with substernal goiter (SG). However, SG surgery has some technical difficulties and a higher risk of complications compared to normal cervical thyroid surgery. Due to these technical difficulties and complication risks, which we also mentioned in our study, SG surgery should be performed by experienced and high-volume endocrine surgeons in centers with a large team and technical equipment. Pre-operative clinical and radiological evaluation and definitions in SG were evaluated in detail in our previous study. Detailed pre-operative evaluation, pre-operative risk assessment, surgical anatomy, anesthesia, appropriate surgical planning and estimation of surgical width are extremely important in SG surgery, where surgical technical difficulties and increased complication risks compared to cervical thyroid surgery come to the fore. In this study, we aimed to evaluate these preoperative and peroperative preparations in detail.

Papillary Thyroid Cancer Presenting with Incidental Skin Lesion: Critical Management of Distant Metastasis.

Papillary thyroid cancer can usually metastasize to neck lymph nodes. Distant metastases are generally seen as solid organ metastases, in contrast, skin metastasis can rarely be seen. We present a case with papillary thyroid cancer diagnosed with skin metastasis as first clinical sign of distant organ metastasis. A 63-year-old male patient admitted with a skin lesion in the left lateral neck. He had undergone subtotal thyroidectomy 14 years ago without relevant history of malignancy. Follicular variant papillary thyroid cancer was detected in the excisional biopsy performed from the cutaneous lesion. A 12 × 10 × 8 mm hyperechoic nodule in the left lobe was detected in USG and evaluated as Bethesta-III in fine needle aspiration biopsy. Bilateral multiple lung metastases were detected on thorax CT, trucut-biopsied from largest nodule and confirmed as metastasis. Carcinoma was not detected in total thyroidectomy, and post-operative multiple RAI therapies were applied. Patients without history of thyroid cancer rarely present with skin metastases and thyroid cancer should not be overlooked in differential diagnosis. Despite meticulous evaluation of the thyroidectomy specimen, tumor may not be detected in the gland. Skin metastasis in papillary thyroid cancer should be evaluated as distant metastasis and investigations for other metastases should be done, and the treatment should be planned in a multidisciplinary manner.

The Reality of Hypoparathyroidism After Thyroidectomy: Which Risk Factors are Effective? Single-Center Study.

Objectives: One of the most common complications of thyroidectomy is hypoparathyroidism and that complication has a multifactorial etiology. The etiology of post-operative hypoparathyroidism is multifactorial, some factors affecting hypoparathyroidism have been revealed in the literature, and there are some conflicting results about this complication. In the present study, we aimed to evaluate pre-operative and intraoperative factors affecting development of hypoparathyroidism. Methods: Data of 542 patients underwent thyroidectomy±central dissection (±lateral dissection) and whose post-operative parathormone values could be obtained, between 2012 and 2020 were collected prospectively and evaluated retrospectively. A parathyroid hormone (PTH) value of <15 pg/mL at the post-operative 4th h was defined as hypoparathyroidism, and a calcium (Ca) value of <8 mg/dl on the 1st post-operative day was defined as biochemical hypocalcemia. Patients were divided into two groups as post-operative hypoparathyroidism (Group 1) and non-hypoparathyroidism (Group 2). In addition, PTH value below the reference value at the post-operative 6th month and/or still needing calcium treatment was defined as permanent hypoparathyroidism. Demographic data of the patients, pre-operative biochemical values, surgical indications, intraoperative findings, post-operative 4th h PTH values, post-operative 1st day calcium values, and pathological examination of the specimen whether there was an unintenionally resected parathyroid gland or not were evaluated as risk factors for hypoparathyroidism. A logistic regression model was used to determine independent risk factors for the development of hypoparathyroidism. Results: Hypoparathyroidism was determined in 124 (22.9%) and hypocalcemia was determined in 120 (22.1%) patients. According to 6-month follow-up period; 110 (20.3%) patients were transient, 7 (1.3%) patients were permanent, and 7 (1.3%) patients data could not be obtained. The hypocalcemia rate was higher in Group 1 (39.3% vs. 14.3%, p<0.0001), also the post-operative 1st day calcium values were lower (8.2+0.7 mg/dl vs. 8.5+0.6 mg/dl; p=0.000). The rate of parathyroid autotransplantation, the rate of parathyroid gland in pathological specimen, and the rate of central dissection were significantly higher in Group 1 compared to group 2 (15.8% vs. 8%; p=0.006; 20% vs. 10.6%; p=0.003; 16.4% vs. 5.3%, p<0.0001, respectively). The difference between the two groups was significant in terms of the number of remaining parathyroids, and the rate of the number of patients with four remaining parathyroids in place was higher in Group 2 than in Group 1 (84.1% vs. 67.9; p=0.000). In the logistic regression analysis, only central dissection is an independent risk factor affecting the development of hypoparathyroidism, and central dissection increases the risk of hypoparathyroidism approximately 2.3 times (p=0.014; OR: 2.336). The other factors were not determined as independent risk factor. Conclusion: Performing central neck dissection with total thyroidectomy may increase the risk of hypoparathyroidism development. The risk of hypoparathyroidism should be considered when evaluating the indications and dissection extent in the central dissection. Maximum effort should be made to preserve the parathyroid glands and their vascularization during central dissection, and if there is a removed parathyroid gland, it should be autotransplanted.