Tc-99m pertechnetate scintigraphy before and after potassium perchlorate administration for the diagnosis of retrosternal goiter

Intrathoracic toxic thyroid nodule causing hyperthyroidism with a multinodular normal functional cervical thyroid gland

Radionuclide scintigraphy with I-131 and Tc-99m pertechnetate ((99)mTc04) has been widely used in detecting toxic nodules. Intrathoracic goiter usually presents as an anterior mediastinal mass. Mostly the connection between intrathoracic mass and the cervical thyroid gland is clearly and easily identified occurring as a result of inferior extension of thyroid tissue in the neck, which is called as secondary intrathoracic goiter. Completely separated, aberrant or in other words primary intrathoracic goiters arise as a result of abnormal embryologic migration of ectopic thyroid closely associated with aortic sac and descend into the mediastinum. Intrathoracic goiters are generally nontoxic nodules existing with mass effect without causing hyperthyroidism. However, mostly reported cases had enlarged thyroid glands in the neck. This report demonstrates the usefulness of I-131 and (99)mTc04 scintigraphy for detecting intrathoracic goiter causing hyperthyroidism with a normal functioned cervical thyroid gland.

Multidetector computed tomography in the preoperative evaluation of retrosternal goiters: a useful procedure for patients for whom magnetic resonance imaging is contraindicated

BACKGROUND

Diagnostic imaging provides useful anatomical and morphological information of cervico-mediastinal goiters. The aim of this study was to assess the usefulness of multidetector computed tomography (MDCT) with multiplanar reformatting and volume rendering reconstructions for the preoperative evaluation of retrosternal goiters in patients for whom magnetic resonance imaging is contraindicated.

METHODS

From March 2006 to January 2009, 34 patients (20 women and 14 men; mean age, 48 years; range, 42-74 years) with suspected cervico-mediastinal goiter were assessed by MDCT after intravenous injection of contrast material. The following parameters were evaluated: morphology, size, and enhancement of thyroid lobes; presence, location, and mediastinal extension of thyroid tissue; and relations with mediastinal vessels and organs. All patients underwent thyroidectomy. A reference group of 34 patients evaluated by single-detector computed tomography was created. The two groups of patients were compared searching for operative time (OT, in hours), hospital stay (HS, in days), and morbidity rate observed after thyroid surgery in all cases.

RESULTS

In 29/34 patients, thyroid was enlarged with left mediastinal extension in 12 cases, right extension in 10 cases, and posterior extension in 7 cases. In 3/34 patients, a normal cervical thyroid connected to the mediastinal goiter through a thin parenchymal stripe was observed. In 2/34 patients, thyroid lobes were enlarged, without mediastinal extension. By comparing the two groups of patients for OT and HS values, a significant reduction to 3.7 +/- 0.1 hours and 4.3 +/- 0.1 days, respectively, was found in the group of MDCT patients, and also a trend to the reduction for morbidity rate (21%) could be recognized.

CONCLUSIONS

MDCT represents a noninvasive tool in the evaluation of retrosternal goiters. High-quality multiplanar reformatting and volume rendering reconstructions allow an optimal analysis of the plunged gland and could reduce OT, HS, and probably the morbidity rate.

Large Retrosternal Goitre: A Diagnostic and Management Dilemma

A substernal goitre is of clinical significance because its growth between the sternum anteriorly and vertebral bodies posteriorly leads to impingement on the surrounding structures and compressive symptoms. The incidence of substernal goitre is documented to vary between .02 and .5%. It accounts for 3-12% of mediastinal masses and is the most common superior mediastinal mass. This condition is important because it presents a diagnostic dilemma as its size and compressive symptoms mimic malignant disease, and an operative dilemma for the approach to its management. We present one of the largest reported retrosternal goitre cases in the literature.

Bócio mergulhante: quando operar?

O bócio mergulhante é uma afecção rara da glândula tireóide, que acomete principalmente mulheres acima de 60 anos, caracterizada por tireóide aumentada de tamanho, peso e volume, que invade a cavidade torácica total ou parcialmente. As condutas clínicas e cirúrgicas no bócio mergulhante ainda são controversas, não havendo um consenso na literatura sobre qual o momento ideal para intervir cirurgicamente nesses pacientes. É preciso conhecer as indicações, conseqüências e complicações do tratamento cirúrgico em determinados tipos de pacientes, como os idosos assintomáticos, avaliando a necessidade real de cirurgia nesses casos. Este trabalho resulta de um relato de caso e uma revisão de publicações sobre tratamento do bócio mergulhante no período de 1995 a 2000. As bases de dados utilizadas foram Medline e Lilacs. Objetiva-se atualizar, orientar e esclarecer dúvidas dos profissionais a respeito desses fatores. Discutem-se os métodos diagnósticos e a conduta terapêutica em casos de bócio mergulhante.