Usefulness of 3D transperineal ultrasound in severe stenosis of the anal canal: preliminary experience in four cases.

BACKGROUND: Organic or functional anal canal stenoses are uncommon conditions that occur in the majority of cases as a consequence of anal diseases. A proper assessment is fundamental for decision making; however, proctological examination and endoanal ultrasound are often unfeasible or very difficult to perform even under local or general anesthesia. We therefore began to use 3D transperineal ultrasound to assess patients. The aim of this study was to compare the results of evacuation proctography and 3D transperineal ultrasound in patients with severe anal canal stenosis. METHODS: Four consecutive patients with high-grade anal canal stenosis were evaluated using both proctography and 3D transperineal ultrasound with a micro-convex transducer between March and June 2011. RESULTS: In all cases, 3D transperineal ultrasound provided detailed information on the length and level of stenosis and on the integrity of the anal sphincters. CONCLUSIONS: Our preliminary experience suggests that 3D transperineal ultrasound makes it possible to plan optimal surgical treatment.

Adrenal ganglioneuroblastoma in pregnant woman: diagnosis with three-dimensional ultrasound.

The diagnostic approach for evaluation of adrenal tumour in pregnant women is a problem. This article presents the multifactorial diagnosis of rare, incidentally detected massive adrenal tumour with 2D and 3D US. Grey-scale 2D and 3D US with tissue harmonic imaging showed inhomogeneous, encapsulated, solid tumour of the right adrenal region. Three-dimensional colour Doppler and power Doppler studies showed ample neovascularization in the tumour and the adrenal vein draining to the inferior vena cava similarly to angiographic studies performed in the past.

[Progress in imaging diagnostics of adrenal neoplasms]. / Postep w diagnostyce obrazowej guzów nadnerczy.

Computed tomography is the modality of choice in imaging of adrenal glands. Density measurements on images without contrast agent are essential for differentiation of adrenal masses. Application of spiral computed tomography for diagnostics of adrenal masses enables sensitive detection of small adrenal tumors and reliable density measurements by elimination of uneven breath-holds effect and minimization of partial volume effect. Tissue harmonic imaging in ultrasonography is a new technique, which enables visualization of abdominal parenchymal organs with higher tissue contrast with less artifacts and is especially useful in ultrasound imaging of difficult-to-image patients with high body weight. Further comparative research will enable to learn the advantages of using that technique in diagnostics of adrenal masses. Magnetic resonance imaging enables very accurate visualization diagnostics of adrenal masses. It is due to its inherent multiplanar imaging capabilities and high tissue contrast of soft tissues which enables very accurate visualization of anatomical structures in adrenal region. Introduction of new techniques of magnetic resonance imaging as chemical shift imaging and dynamic studies with paramagnetic contrast agent enables accurate differentiation of adrenal cortex adenomas from non-adenomas. In case of difficulties in adrenal diagnostics magnetic resonance imaging is often a problem solving examination in regard to other imaging techniques of adrenal region.

[Magnetic resonance techniques used in the differentiation of adrenal tumors]. / Techniki rezonansu magnetycznego przydatne w róznicowaniu guzów nadnerczy.

Noninvasive differentiation of adrenal masses by imaging studies as computed tomography and magnetic resonance imaging is an accepted diagnostic procedure in patients with extraadrenal neoplasm and discovered on imaging studies adrenal mass or in patients with incidentally discovered adrenal mass. Significant impact on possibilities of differentiation of adrenal masses with magnetic resonance imaging was due to introduction to adrenal imaging such techniques as chemical shift imaging and dynamic imaging with paramagnetic contrast agent. Differentiation of adrenal masses with magnetic resonance imaging involves following parameters: tumor diameter, signal intensity of adrenal mass on T2 weighted images, lipid contents in adrenal tumor evaluated with chemical shift imaging and washout of paramagnetic contrast agent from adrenal mass evaluated with dynamic examination. The best results, reaching 100% sensitivity and 100% specificity in differentiation adrenal adenomas from non-adenomas, can be achieved by combined analysis of all mentioned parameters. In regard to availability and costs computed tomography not magnetic resonance imaging is the examination of choice in visualization of adrenal glands and their pathology and in differentiation of adrenal masses. Adrenal tumors on non-enhanced images with density below 0 Hounsfield units can reliably be diagnosed as adenomas, whereas adrenal tumors with density above 20 Hounsfield units can reliably be diagnosed as non-adenomas. Tumors with density in 0-20 Hounsfield range are ambiguous in character, that in many cases can be determined in magnetic resonance imaging.

Discriminatory power of MRI for differentiation of adrenal non-adenomas vs adenomas evaluated by means of ROC analysis: can biopsy be obviated?

The purpose of our study was to evaluate the discriminatory power of MRI in high-field magnet (1.5 T) for differentiation of adrenal non-adenomas vs adenomas assessing the following parameters separately and in combination: mean diameter of adrenal mass; previously described and new ratios as well as index calculated from signal intensity (SI) on SE T2-weighted images, chemical shift imaging (CSI), and Gd-DTPA-enhanced dynamic studies. One hundred eight adrenal masses (36 non-hyperfunctioning adenomas, 27 pheochromocytomas, 23 aldosterone-secreting adenomas, 20 malignant masses and 2 cortisol-secreting adenomas) in 95 patients were evaluated with SE sequences, CSI and Gd-DTPA dynamic studies. Indices and ratios of SI for all examined MRI methods were calculated and examined retrospectively for significance of differences between the groups with calculation of sensitivity and specificity. Receiver operating characteristics (ROC) analysis of calculated parameters in combination was performed. The multifactorial analysis of all four parameters, including size of the tumor, T2(liver) index, CSI ratio reflecting lipid content in the tumor and Wo(max/last) ratio reflecting maximal washout of contrast agent from the tumor had 100 % sensitivity and 100 % specificity in characterization of adrenal non-adenoma. The best performance of combination of mean tumor diameter with single MRI SI parameter was achieved in combination with T2(liver) index for all adrenal masses (area under ROC 0.987) and CSI ratio for non-hyperfunctioning adrenal masses (area under ROC 0.991). Magnetic resonance imaging enables sensitive and specific diagnosis of adrenal non-adenoma.

Multiple adrenal masses: MRI tissue differentiation of pheochromocytoma and adenoma at 1.5 T.

We present the case of 38-year-old hypertensive patient with bilateral adrenal masses and with clinical and biochemical suspicion of pheochromocytoma. Magnetic resonance imaging at 1.5 T established correct diagnosis of coexisting adrenal pheochromocytoma and adenoma (nonhyperfunctioning). The case supports the usefulness of MRI for definitive evaluation of bilateral adrenal masses in patients with suspicion of pheochromocytoma.

Magnetic resonance imaging differentiation of adrenal masses at 1.5 T: T2-weighted images, chemical shift imaging, and Gd-DTPA dynamic studies.

The purpose of our study was to assess the potential role of spin-echo (SE), chemical shift, and gadolinium-enhanced magnetic resonance imaging (MRI) in the differentiation of adrenal masses. Seventy-two adrenal masses (26 nonhyperfunctioning adenomas, 16 aldosterone-secreting adenomas and 6 other different benign cortical masses, 18 pheochromocytomas, and 6 malignant masses) in 63 patients were evaluated with spin-echo sequences, chemical shift imaging (CSI) and gadolinium diethylenetriamine penta-acetic acid (Gd-DTPA) dynamic studies. Ratios and indices of signal intensity for all examined MRI methods were calculated and examined for significance of difference between different types of adrenal masses. Quantitative magnetic resonance evaluation of adrenal masses showed significant differences (at least alpha < 0.01) between nonhyperfunctioning adenomas vs. pheochromocytomas or vs. malignant lesions or vs. aldosterone-secreting adenomas and between pheochromocytomas vs. malignant lesions. The most specific indicators of adrenal mass character proved to be the CSI ratio based on opposed-phase and in-phase two-dimensional fast low-angle shot (FLASH) images, reflecting lipid content in the lesion, and Gd-DTPA dynamic studies ratios reflecting contrast agent inflow and washout in the lesion: WoMAX/LAST and Dyn1.2-3.2. There was no overlap of CSI ratio between adenomas and pheochromocytomas. The overlap of ranges of CSI ratio between nonhyperfunctioning adenomas and aldosterone-secreting adenomas was only 18.5%. There was no overlap of WoMAX/LAST ratio between adenomas and pheochromocytomas, or adenomas and malignant lesions. The overlap of ranges of Dyn1.2-3.2 ratio between pheochromocytomas and malignant lesions was only 17.6%. MRI enables good visualization and specific characterization of adrenal masses. The optimal MRI protocol for the adrenal region is presented.

Nuclear magnetic resonance spectroscopy to determine the micellar cholesterol in human bile.

The cholesterol of gallstones comes from the vesicular rather than the micellar phase of bile. Progress in this field has been limited because conventional analytical methods disturb the distribution of cholesterol between the two phases. The resonance of the cholesterol C6 proton occurs at a chemical shift of 5.4 ppm, to be shown by 2D NMR to be specific for biliary cholesterol, and arises only from the micellar mode. Thus integration of the C6 proton resonance peak area provides a direct non-invasive determination of the cholesterol distribution in human bile.