Middle thyroid vein tumor thrombus in metastatic papillary thyroid microcarcinoma: A case report and review of literature.

BACKGROUND: Although papillary thyroid microcarcinoma (PTMC) is not considered a threatening tumor, in some cases, it can be aggressive. Metastatic thrombosis of papillary thyroid carcinoma, follicular thyroid carcinoma, Hürthle cell carcinoma, poorly differentiated thyroid carcinoma and anaplastic thyroid carcinoma have been reported in the literature, but there have been no reports about PTMC. CASE SUMMARY: A 45-year-old woman presented with a thyroid mass and thrombosis in a middle thyroid vein during a physical examination. She had no symptoms, and the physical examination showed no positive signs. Subsequent ultrasonography-guided fine-needle aspiration biopsy results indicated an atypical lesion of ambiguous significance, with some actively growing cells (TBSRTC III) and the BRAFV600E mutation not present. This patient underwent left thyroidectomy, isthmus lobectomy, prophylactic central lymph node dissection and thromboembolectomy. Postoperative pathology showed papillary microcarcinoma of the left thyroid, and the thrombus in the middle thyroid vein was a tumor thrombus. CONCLUSION: Middle thyroid vein tumor thrombus is an extremely rare condition in PTMC, but it does exist. Lobectomy and thromboembolectomy may be an option for patients with thrombi in the middle vein of the thyroid, and we strongly suggest close follow-up of these patients.

Anatomía quirúrgica de la vena tiroidea media: prevalencia en 100 tiroidectomías totales consecutivas / Surgical anatomy of the median thyroid vein: prevalence in 100 consecutive total thyroidectomies

El estudio de las venas tiroideas no ha recibido una investigación tan exhaustiva como lo tuvieron las arterias tiroideas y los nervios laríngeos en relación a la cirugía tiroidea.De los tres pedículos venosos de la glándula tiroides, el medio, de lejos es el menos estudiado. La vena tiroidea media es inconstante y es el primer elemento vascular de la glándula tiroides que debe ser seccionado antes de luxar el lóbulo hacia medial para evaluar sus relaciones posteriores. Su lesión puede provocar sangrado intraoperatorio dificultando secundariamente la identificación del nervio laríngeo inferior y las glándulas paratiroides, próximas a la misma. Se realizó un estudio descriptivo de corte transversal evaluando la pesencia, número, simetría y asociación de la vena tiroidea media con variables tales como edad y sexo del paciente, así como la hiperfuncionalidad de la glándula tiroides y la presencia del tubérculo de Zuckerkandl en 100 tiroidectomías totales llevadas a cabo en el Instituto Nacional del Cáncer y en el Servicio de Otorrinolaringología del Hospital Central del Instituto de Previsión Social del Paraguay. La prevalencia global de vena tiroidea media fue del 74 %. En el lóbulo derecho, la vena se presentó en el 60 %, mientras que en el lóbulo izquierdo en el 53 %. En el 38 % se encontró la vena en ambos lóbulos. En 4 pacientes se localizaron venas tiroideas medias dobles, en una de ellas fue bilateral. El mayor porcentaje de las venas tiroideas medias se originó en el tercio medio del lóbulo, el 72 % en el lado derecho y el 70% en el izquierdo. No se encontró asociación entre la presencia de la vena tiroidea media y la edad, sexo, estado de hiperfunción glandular, así como tampoco con la presencia del tubérculo de Zuckerkandl.

The study of the thyroid veins has not received an investigation as extensive as the thyroid arteries and laryngeal nerves did in relation to thyroid surgery. Of the three veins pedicles of the gland the middle is far the least studied. This vein is inconstant and is the first vascular element of the gland that must be sectioned before the medial lobe is dislocated to evaluate ist posterior relationships. His injury can cause intraoperative bleeding, making it difficult to identify the inferior laryngeal nerve and the parathyroid glands, proximal to it. A descriptive crossseccional study was carried aot evaluating the presence, number, symmetricity and association of the middle thyroid vein with variables such as age and sex of the patient, as well as the hyperfunctionality of the gland and the presence of the Zuckerkandl tubercle in 100 total thyroidectomies undergoing at the National Cancer Institute and the ENT Service of the Social Security Institute´s Central Hospital. The overall prevalence of the middle thyroid vein was 74%. In the right lobe the vein appeared in 60% while in the left lobe in 53 %. Double middle thyroid vein was found in 4 patients, in one of them it was bilateral. The highest percentage of the middle thyroid veins originated in the middle third of the lobe, 72 % on the right and 70% on the left side. No association was found between the presence of the vain and age and sex, the state of glandular hyperfunstion, as well as the presence of Zuckerkandl tubercle.

Review of the Variations of the Superficial Veins of the Neck.

The venous drainage of the neck can be characterized into superficial or deep. Superficial drainage refers to the venous drainage of the subcutaneous tissues, which are drained by the anterior and external jugular veins (EJVs). The brain, face, and neck structures are mainly drained by the internal jugular vein (IJV). The superficial veins are found deep to the platysma muscle while the deep veins are found encased in the carotid sheath. The junction of the retromandibular vein and the posterior auricular vein usually form the EJV, which continues along to drain into the subclavian vein. The anterior jugular vein is usually formed by the submandibular veins, travels downward anterior to the sternocleidomastoid muscle (SCM), and drains either into the EJV or the subclavian vein. Other superficial veins of the neck to consider are the superior, middle, and inferior thyroid veins. The superior thyroid and middle thyroid veins drain into the IJV whereas the inferior thyroid vein usually drains into the brachiocephalic veins.

Selective venous sampling supports localization of adenoma in primary hyperparathyroidism.

BACKGROUND: Selective venous sampling (SVS) is an invasive localization study for persistent or recurrent hyperparathyroidism. PURPOSE: To assess the role of SVS in addition to non-invasive imaging for primary hyperparathyroidism (pHPT). MATERIAL AND METHODS: This study was approved by the institutional review board and included 14 patients who underwent SVS and subsequent parathyroidectomy between January 2014 and April 2017 following a clinical diagnosis of pHPT. All patients underwent pre-SVS non-invasive imaging, including ultrasound, computed tomography (CT), and 99mTc-MIBI scintigraphy, and sensitivity was assessed using the operative and pathological findings. RESULTS: In all but one case, a single parathyroid adenoma was responsible for the pHPT; the remaining case exhibited a chemical response following surgical removal of parathyroid tissue. The sensitivity (%) for ultrasound, CT, 99mTc-MIBI scintigraphy, and SVS was 76.9, 84.6, 69.2, and 76.9, respectively. SVS yielded positive results in four patients with discordant results and one patient with non-detectable results on imaging. In seven patients, a significant increase in the intact parathyroid hormone level was recognized only in the thyroid veins. The procedure time was in the range of 52-183 min (median = 89.5 min). CONCLUSION: The addition of SVS to a non-invasive imaging study would be helpful to locate the responsible lesion of pHPT with discordant or non-detectable results on imaging for initial surgical treatment as well.

Selective venous sampling for primary hyperparathyroidism: how to perform an examination and interpret the results with reference to thyroid vein anatomy.

Primary hyperparathyroidism (pHPT) causes hypercalcemia. The treatment for pHPT is surgical dissection of the hyperfunctioning parathyroid gland. Lower rates of hypocalcemia and recurrent laryngeal nerve injury imply that minimally invasive parathyroidectomy (MIP) is safer than bilateral neck resection. Current trends in MIP use can be inferred only by reference to preoperative localization studies. Noninvasive imaging studies (typically preoperative localization studies) show good detection rates of hyperfunctioning glands; however, there have also been cases of nonlocalization or discordant results. Selective venous sampling (SVS) is an invasive localization method for detecting elevated intact parathyroid hormone in the thyroid and/or internal jugular and brachiocephalic veins. SVS was developed mainly for postoperative patients with persistent or recurrent pHPT; however, SVS could also be useful before initial operations due to its high sensitivity to pHPT. Currently, SVS is generally indicated for recurrent HPT, and for cases with negative imaging study results for HPT or discordant results. Multi-detector row helical CT is useful for imaging the anatomy of the jugular and thyroid veins. Knowledge of the thyroid vein anatomy enables the creation of sampling points in the internal jugular and brachiocephalic veins for catheterization of the thyroid veins and venous anastomoses.

Anatomical variation of thyroid veins on contrast-enhanced multi-detector row computed tomography.

OBJECTIVE: The objective of this study was to clarify the anatomical variation of thyroid veins into the systemic vein using contrast-enhanced multi-detector row computed tomography (MDCT). DESIGN AND METHODS: The subjects were 80 patients (34 males and 46 females; mean age, 50.1 years; age range, 15-92 years) with neck diseases who underwent MDCT. The number and location of inflow points of the thyroid veins into the systemic vein, and the length from the junction of bilateral brachiocephalic veins to the orifice of inferior thyroid vein were investigated by reviewing the axial and coronal images. RESULTS: All superior thyroid veins were detected. Right and left middle thyroid veins were identified in 39 and 29 patients, respectively. Right inferior thyroid veins, left inferior thyroid veins, and common trunks were detected in 43, 46, and 39 patients, respectively; in five patients, two left thyroid veins were identified. All left inferior thyroid veins and 34 common trunks flowed into the innominate vein, while right ones had some variations in inflow sites. Mean lengths were 3.01±1.30 cm (range, 0.5-6.19) and 2.04±0.91 cm (0.5-4.4) in the left inferior thyroid vein and common trunk, and 1.96±1.05 cm (0.81-4.8) and 1.65±0.69 cm (0.63-2.94) in the right one flowing into the right internal jugular vein and the innominate vein, respectively. CONCLUSIONS: The numbers and orifices of thyroid veins were identified at high rates on contrast-enhanced MDCT. This strategy can provide anatomical information before selective venous sampling for measurements of parathyroid hormone.

Preservation of the inferior thyroidal vein reduces post-thyroidectomy hypocalcemia.

OBJECTIVES/HYPOTHESIS: We present a novel surgical method to preserve the inferior thyroidal vein and investigated its effectiveness in reducing postoperative transient hypocalcemia. STUDY DESIGN: Retrospective cohort study. METHODS: From January 2012 to October 2012, 109 total thyroidectomy patients with bilateral central neck dissection were included in this study. The controls were 96 sex- and age-matched patients who underwent a conventional total thyroidectomy from January 2011 to December 2011. Differences in the incidence of postoperative hypocalcemia, serial ionized calcium levels, and postoperative day 1 intact parathyroid hormone levels were analyzed using χ(2) and independent t tests. RESULTS: Age, male-to-female ratio, T stage, N stage, thyroid size, number of inadvertently excised parathyroid glands, operation time, number of harvested central lymph nodes, and total drainage amount were not significantly different between the groups. By saving the bilateral inferior thyroidal veins, the incidence of both biochemical and symptomatic hypocalcemia were significantly decreased compared to the controls (P = .044 and .012, respectively). The number of patients whose postoperative day 1 intact parathyroid hormones were <10 pg/mL was significantly lower in the study group (P = .000). Average ionized calcium levels were significantly higher in study-group patients; among the hypocalcemic patients, postoperative ionized calcium levels in the study group showed significantly faster recovery times than the control group. CONCLUSIONS: The described surgical method preserves the inferior thyroidal vein and may reduce post-thyroidectomy hypocalcemia without disturbing the extent of central lymph node harvesting. Preservation of the bilateral inferior thyroidal veins is important for reducing hypocalcemia and promoting faster recovery following thyroidectomy.

Routine exposure of recurrent laryngeal nerve in thyroid surgery can prevent nerve injury.

To determine the value of dissecting the recurrent laryngeal nerve during thyroid surgery with respect to preventing recurrent laryngeal nerve injury, we retrospectively analyzed clinical data from 5 344 patients undergoing thyroidectomy. Among these cases, 548 underwent dissection of the recurrent laryngeal nerve, while 4 796 did not. There were 12 cases of recurrent laryngeal nerve injury following recurrent laryngeal nerve dissection (injury rate of 2.2%) and 512 cases of recurrent laryngeal nerve injury in those not undergoing nerve dissection (injury rate of 10.7%). This difference remained statistically significant between the two groups in terms of type of thyroid disease, type of surgery, and number of surgeries. Among the 548 cases undergoing recurrent laryngeal nerve dissection, 128 developed anatomical variations of the recurrent laryngeal nerve (incidence rate of 23.4%), but no recurrent laryngeal nerve injury was found. In addition, the incidence of recurrent laryngeal nerve injury was significantly lower in patients with the inferior parathyroid gland and middle thyroid veins used as landmarks for locating the recurrent laryngeal nerve compared with those with the entry of the recurrent laryngeal nerve into the larynx as a landmark. These findings indicate that anatomical variations of the recurrent laryngeal nerve are common, and that dissecting the recurrent laryngeal nerve during thyroid surgery is an effective means of preventing nerve injury.

Anatomía quirúrgica del drenaje venoso en la región del triángulo carotídeo / Surgical anatomy of jugular vein tributaries

Background: The main tributaries of the internal jugular vein join at cervical level through the venous thyrolinguofacial trunk. This trunk is classically described as formed by the union of the facial, superior thyroid and lingual veins. Aim: To evaluate variations in the formation of the thyrolinguofacial trunk in human cadavers. Material and Methods: Thirty hemi-necks were dissected in human cadavers of nine men and six women, with ages ranging between 29 and 50 years, and analyzed by direct observation. Results: In 16 hemi-necks (53.3 percent), the trunk was thyrolinguofacial; in seven (23.3 percent), it was linguofacial; in six (20 percent), it was thyrolingual and in one case (3.3 percent) it was thyrolinguo pharyngofacial. No thyrofacial trunk formation was found. There was a correlation between the diameter of the internal jugular vein and of the venous trunk formed by these veins. Conclusions: There are morphological changes in the formation patterns of facial, lingual and superior thyroid veins. This information is useful for surgical oncology, plastic surgery, head and neck surgery and radiology.

Los principales afluentes de la vena yugular interna se incorporan a nivel cervical por medio del tronco venoso tirolinguofacial. Clásicamente se ha descrito su formación por la unión de la vena facial, lingual y tiroidea superior. El objetivo de este estudio fue determinar las variaciones en la presentación del tronco tirolinguofacial en cadáveres humanos de la región del Maule, Chile. Se disecaron 30 hemicuellos pertenecientes a 15 cadáveres humanos de ambos sexos, con un rango de edad entre 29 y 50 años, y se analizaron mediante observación directa. Se observó la formación de tronco venoso en la totalidad de los casos, siendo 53,3 por ciento correspondiente al tronco de tipo tirolinguofacial, 23,3 por ciento linguofacial, 20 por ciento tirolingual y sólo un 3,3 por ciento el tronco tirolinguofaringofacial. No se encontró la formación del tronco venoso de tipo tirofacial. Además se encontró una correlación significativa entre el diámetro de la vena yugular interna y el tronco venoso conformado por estas venas. Por lo tanto, existen variaciones morfológicas en los patrones de conformación de las venas facial, lingual y tiroidea superior, siendo estos datos de importancia para áreas de cirugía oncológica, cirugía plástica, cirugía de cabeza y cuello y radiología.

Aspectos macroscópicos da desembocadura das veias facial, lingual e tireóidea superior, na veia jugular interna / Macroscopic aspects of the discharge of facial, lingual and superior thyroid veins into the internal jugular vein

A veia jugular interna, no seu trajeto descendente no pescoço, recebe tributárias como a veia facial, a veia lingual e a veia tireóidea superior. As veias da cabeça e do pescoço se anastomosam livremente, promovendo, com freqüência, variações anatômicas na sua distribuição, até mesmo diferenças nos antímeros de um mesmo indivíduo. Essa grande tendência das veias de sofrerem variações anatômicas nos motivou a ampliar as investigações com relação à desembocadura das veias facial, lingual e tireóidea superior na veia jugular interna, promovendo a identificação desses vasos em peças anatômicas cadavéricas utilizadas nos laboratórios de ensino de anatomia humana. Para este trabalho, foram feitas observações macroscópicas, na forma da desembocadura das veias facial, lingual e tireóidea superior, na veia jugular interna, em 37 antímeros de cabeças humanas, fixadas em formol a 10%, sendo 11 cabeças com antímeros direito e esquerdo, 9 cabeças com antímero esquerdo e 6 cabeças com antímero direito. Nossos resultados mostraram que a veia jugular interna recebe as veias tributárias facial, lingual e tireóidea superior de maneira variada, sendo 51% com desembocadura direta dessas tributárias na veia jugular interna, 38% com formação de um tronco venoso curto, denominado tíreo-línguo-facial, e em apenas 11% a formação do tronco línguo-facial.

The internal jugular vein, in its descending course at the neck, receives tributaries among which there are: the facial vein, the lingual vein and the superior thyroid vein. The veins from the head and neck anastomose freely, and this frequently causes anatomical variations in their distribution even between the two antimeres of the same individual. This great tendency of the veins of displaying anatomical variations prompted us to widen the investigations concerning the discharge of facial, lingual and superior thyroid veins at the internal jugular vein by identifying these vessels in anatomic pieces used at the teaching laboratories of human anatomy. For this paper, macroscopic observations were made by opening the facial, lingual and superior thyroid veins into the internal jugular vein in 37 antimeres of human heads fixed in 10% formol solution: 11 heads with right and left antimeres, nine with left antimere and six with right antimere. Our results showed that the internal jugular vein receives drainage from the facial, lingual and superior thyroid vein in varied ways: in 51% of the instances, these tributaries open directly into the internal jugular vein, in 38% they form a short venous trunk named thyro-lingual-facial trunk and in only 11% there is a lingual-facial trunk.

Drenaje de las Venas Facial, Lingual y Tiroidea Superior en el Hombre / Drainage of Facial, Lingual and Superior Thyroid Veins in Humans

La gran diversidad de descripciones acerca de las afluencias de las venas facial, lingual y tiroidea superior en el hombre, estas presentan una serie de controversias entre los autores investigados. Buscando ofrecer un patrón para la formación de troncos venosos a partir de las referidas venas, los autores realizaron la disecación de 42 faces laterales del cuello de cadáveres humanos adultos, de ambos sexos, con edades variadas y fijados en formaldehido a 10%. Se observó la formación de troncos venosos en 59,5% de los casos, habiendo ocurrido formación del tronco tiroilingofacial en 38,1%, del tronco lingofacial en 14,2%, del tronco tiroilingual en 4,8% y del tronco tiroilingofaringofacial en apenas 2,4%. No fue encontrada la formación del tronco tiroifacial descrito en la literatura. En los 40,5% de los casos en los que no hubo formación de troncos venosos, las venas presentaron desembocaduras solitarias.

Despite the great diversity of descriptions concerning the inflows of the facial, lingual and superior thyroid veins in man, they present important controversies between the studied authors. Aiming to supply a pattern for the formation of venous trunks by the cited veins, the authors analyzed 42 lateral faces of dissected adult human cadavers of both genders, different ages and preserved in a 10% solution of formaldehyde. The study revealed the formation of venous trunks in 59,5% of the cases, the thyroid-lingual-facial trunk appears in 38,1%, the lingual-facial trunk in 14,2%, the thyroid-lingual trunk in 4,8% and the thyroid-lingual-pharyngeal-facial trunk in just 2,4%. It was not found the formation of thyroid-facial trunk described in the analyzed literature. 40,5% of the cases appears with no venous trunk formation, in those situations the veins end alone.