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Abstract Background The purpose of this study was to assess the advantages and disadvantages of 3D gray-scale and power Doppler ultrasound, including thin slice volume rendering (TSVR), applied for evaluation of thyroid nodules. Methods The retrospective evaluation by two observers of volumes of 71 thyroid nodules (55 benign, 16 cancers) was performed using a new TSVR technique. Dedicated 4D ultrasound scanner with an automatic 6-12 MHz 4D probe was used. Statistical analysis was performed with Stata v. 8.2. Results Multiple logistic regression analysis demonstrated that independent risk factors of thyroid cancers identified by 3D ultrasound include: (a) ill-defined borders of the nodule on MPR presentation, (b) a lobulated shape of the nodule in the c-plane and (c) a density of central vessels in the nodule within the minimal or maximal ranges. Combination of features provided sensitivity 100% and specificity 60-69% for thyroid cancer. Calcification/microcalcification-like echogenic foci on 3D ultrasound proved not to be a risk factor of thyroid cancer. Storage of the 3D data of the whole nodules enabled subsequent evaluation of new parameters and with new rendering algorithms. Conclusions Our results indicate that 3D ultrasound is a practical and reproducible method for the evaluation of thyroid nodules. 3D ultrasound stores volumes comprising the whole lesion or organ. Future detailed evaluations of the data are possible, looking for features that were not fully appreciated at the time of collection or applying new algorithms for volume rendering in order to gain important information. Three-dimensional ultrasound data could be included in thyroid cancer databases. Further multicenter large scale studies are warranted.

Although elastography can enhance the differential diagnosis of thyroid nodules, its diagnostic performance is not ideal at present. Further improvements in the technique and creation of robust diagnostic criteria are necessary. The purpose of this study was to compare the usefulness of strain elastography and a new generation of elasticity imaging called supersonic shear wave elastography (SSWE) in differential evaluation of thyroid nodules. Six thyroid nodules in 4 patients were studied. SSWE yielded 1 true-positive and 5 true-negative results. Strain elastography yielded 5 false-positive results and 1 false-negative result. A novel finding appreciated with SSWE, were punctate foci of increased stiffness corresponding to microcalcifications in 4 nodules, some not visible on B-mode ultrasound, as opposed to soft, colloid-inspissated areas visible on B-mode ultrasound in 2 nodules. This preliminary paper indicates that SSWE may outperform strain elastography in differentiation of thyroid nodules with regard to their stiffness. SSWE showed the possibility of differentiation of high echogenic foci into microcalcifications and inspissated colloid, adding a new dimension to thyroid elastography. Further multicenter large-scale studies of thyroid nodules evaluating different elastographic methods are warranted.

A majority of incidentally found adrenal tumors derive from the adrenal cortex. The aim of our study was evaluation of the incidence of chromaffin tumors in a group of 1,111 patients with adrenal incidentalomas. In this group there were 803 women and 308 men, aged 10-87 years. Clinical examination, imaging studies (ultrasound scans, CT, and MRI if necessary), and hormonal determinations (cortisol, ACTH and androgens in the blood, dexamethasone suppression test, urinary excretion of 17-OHCS, aldosterone and 17-KS, as well as PRA/aldosterone stimulation test and metanephrines in hypertensive patients and those with density in CT over 20 HU) were used. In 380 patients treated by surgery (mainly by laparoscopic approach), histological and immunocytochemical examinations were performed. Clinical examination revealed hypertension in 25% of the patients under study. Chromaffin tumors were detected in 43 patients, 33 women, and 10 men aged 20-75 years: pheochromocytoma in 36 (malignant in 3); chromaffin cells hyperplasia in 2; paraganglioma in 3; ganglioneuroblastoma in 1; ganglioneuroma in 1; and schwannoma in 2. The tumors' diameter ranged between 1.1 and 20.0 cm, density=25 Hounsfield units (HU) or more before contrast medium injection. Hypertension was present in 53% of these patients. The urinary metanephrines excretion was elevated in 31 of 38 patients, in whom the determinations were done. Chromaffin tumors were detected in 4% (pheochromocytomas in 3%) of 1,111 patients with adrenal incidentalomas. Malignancy was present in 9% of 43 patients with chromaffin tumors. High density in CT was a very important diagnostic finding in the incidentally found medullary tumors.

The aim of the study was differential evaluation of new and classical sonographic features of benign thyroid nodules and thyroid cancer with three-dimensional gray-scale sonography and evaluation of the effectiveness of the thin-slice surface rendered images in comparison with multiplanar reformation (MPR) presentation. Fifty-four thyroid nodules were interactively evaluated with thin-slice smooth surface rendering: shape in the c-plane (parallel to the probe) and evaluation of echogenicity, margins and calcification/microcalcification-like echogenic foci in the a-plane (plane of the probe). Evaluation of the level of agreement in readers' interpretation and between sonographic techniques was performed using the kappa statistic. Surface rendering permitted visualization of the shape of the nodule in the c-plane in all cases, in contrast to only up to 48% of cases in MPR evaluation. Lobulated nodule shape in the c-plane was 82-100% sensitive and 47-53% specific in diagnosis of carcinoma. Surface rendered images showed more calcification/microcalcification-like echogenic foci than MPR ones. The level of agreement between the observers in the evaluation of features of thyroid nodules and the agreement between features of thyroid nodules on MPR and surface-rendered images showed at least moderate reproducibility (kappa>or=0.41). Three-dimensional thin-slice surface rendering sonography appears to be a feasible and effective method for thyroid nodule evaluation.

In order to evaluate the role of beta-endorphin in the pathogenesis of obesity and essential hypertension 44 subjects were investigated: 12 nonobese hypertensives, 11 obese hypertensives, 11 obese normotensives and 10 normal subjects. Plasma concentrations of beta-endorphin and cortisol were measured by radioimmunological and ACTH by immunoradiometric methods. The plasma concentrations and the circadian rhythms of ACTH and cortisol secretion were normal in all groups investigated. A circadian rhythm of beta-endorphin secretion was demonstrated in nonobese hypertensives and in normal subjects. The plasma concentrations of beta-endorphin were twice higher than those in nonobese subjects. Also, in all obese patients the circadian rhythm of beta-endorphin secretion was blunted. The increased concentrations and the altered circadian rhythm of beta-endorphin in all obese subjects may point to a role of beta-endorphin in the pathogenesis of obesity rather than in that of essential hypertension.