Abdominal aortic aneurysm: rupture associated with the high-attenuating crescent sign.

Purpose: To determine the histopathologic features of the ruptured abdominal aortic aneurysm associated with the high-attenuating crescent sign on computed tomographic (CT) scans and to suggest a possible mechanism for the rupture.

Materials And Methods: Histopathologic examination was performed with specimens from six patients with a ruptured aneurysm associated with the high-attenuating crescent sign and from eight patients with a nonruptured aneurysm and in whom the high-attenuating crescent sign was not present.

Results: Acute hemorrhage in the mural thrombus or aneurysmal wall coincident with the high-attenuating crescent sign was present in all six patients with a ruptured aneurysm.

Gallbladder disease: appearance of associated transient increased attenuation in the liver at biphasic, contrast-enhanced dynamic CT.

Purpose: To evaluate the frequency, location, and appearance of transient increased attenuation in the liver during arterial-phase helical or incremental computed tomography (CT) in patients with gallbladder disease without hepatic extension.

Materials And Methods: Findings in dynamic CT examinations in 31 patients with surgically proved gallbladder disease not extending into the liver and in 31 control patients without gallbladder disease were retrospectively reviewed and correlated with findings in other imaging examinations.

Results: Areas of transient increased hepatic attenuation (n = 27) were identified in 22 of 31 patients with gallbladder disease and in only one of 31 control patients.

Three-dimensional surface displays of perfusion SPET in the evaluation of patients with pulmonary emphysema for thoracoscopic lung volume reduction surgery.

A modified, three-dimensional display was applied to 99Tcm-macroaggregated albumin (99Tcm-MAA) SPET to help assess the effect of thoracoscopic lung volume reduction surgery (LVRS) on regional lung perfusion. Surface-rendered three-dimensional images for 99Tcm-MAA and xenon-133 (133Xe) equilibrium (EQ) SPET were obtained in 11 patients with pulmonary emphysema before and after LVRS. A single three-dimensional fusion display of both images was then reconstructed, and the perfused lungs were transparently visible through the lung contours delineated by the three-dimensional 133Xe EQ image.

Radionuclide angiography and ventilation/perfusion studies in two patients with systemic arterial supply to the basal segment of the left lung.

The findings of radionuclide studies in two adult men with systemic arterial supply to the basal segment of the left lung without sequestration are reported. Radionuclide angiography with Tc-99m human serum albumin-diethylenetriamine showed that the lung was perfused by the systemic circulation rather than by the pulmonary artery. Ventilation and perfusion scans with Xe-133 and Tc-99m MAA showed a V/Q mismatch in this area, suggesting the presence of normal bronchial communication without a pulmonary arterial supply.

CT of acquired abnormalities of the portal venous system.

Computed tomography (CT), including biphasic contrast material-enhanced helical dynamic scanning and three-dimensional CT angiography, is useful in evaluating acquired abnormalities of the portal venous system. At contrast-enhanced CT, portal venous thrombus usually manifests as low-attenuation intraluminal lesions combined with enlargement of the affected portal vein. Cavernous transformation, a masslike network of intertwined veins that provides an alternative pathway for a stenosed or occluded portal vein, is depicted as multiple, periportal vascular structures.

Biphasic contrast-enhanced multisection dynamic MR imaging of the liver: potential pitfalls.

Biphasic contrast material-enhanced dynamic magnetic resonance (MR) imaging is an important technique for evaluating liver disease. However, several potential diagnostic pitfalls may be encountered, including lobar, segmental, subsegmental, and subcapsular hyperperfusion abnormalities; early-enhancing pseudolesions, particularly in the medial segment of the left hepatic lobe; heterogeneous hyperperfusion abnormalities throughout the liver; and hypointense pseudolesions due to vascular artifacts, unenhanced hepatic vessels, partial volume artifacts, magnetic susceptibility artifacts, and regenerative nodules in cirrhosis. These abnormalities sometimes have appearances similar to those of true lesions or tumor spread to the surrounding liver parenchyma on arterial-dominant phase dynamic MR images.

Takayasu arteritis: protean radiologic manifestations and diagnosis.

Diagnosis of Takayasu arteritis is difficult because the clinical features are similar to those of other diseases. In early-phase Takayasu arteritis, computed tomography (CT) and magnetic resonance (MR) imaging show thickening of the aortic wall. Late-phase Takayasu arteritis has been classified into four types: classic pulseless disease (type I), a mixed type (type II), the atypical coarctation type (type III), and the dilated type (type IV).

[Usefulness of 3-D dynamic pulmonary xenon-133 SPECT for thoracoscopic lung volume reduction surgery in patients with pulmonary emphysema].

Six patients with pulmonary emphysema scheduled to undergo thoracoscopic lung volume reduction surgery (TLVRS) were evaluated by three-dimensional (3-D) dynamic pulmonary xenon-133 SPECT. Serial 30-second dynamic SPECT data for equilibrium and washout (for 5 min) were acquired using a continuous repetitive rotating acquisition mode with a triple-detector SPECT system. SPECT data were reconstructed to 3-D images with a color, surface-rendering technique, and a 3-D fusion image of the 3-min washout image over the equilibrium image was obtained.

Thin-section oblique CT with 25 degrees cranially tilted images. Evaluation of pulmonary tumors adjacent to the interlobar fissures.

Purpose: Thin-section oblique CT with cranially tilted axial scans can provide better visualization of the interlobar fissures than thin-section CT with conventional axial scans. The purpose of this study was to evaluate the usefulness of oblique CT scans for pulmonary tumors adjacent to the interlobar fissures.

Material And Methods: Cranially tilted and conventional axial images were obtained by thin-section CT in 10 patients with solitary pulmonary tumors adjacent to the interlobar fissures.

High-resolution dynamic MR imaging of hepatocellular carcinoma with a phased-array body coil.

High spatial resolution dynamic magnetic resonance (MR) imaging performed with a phased-array body coil is a useful tool for evaluating hepatocellular carcinoma. The examination consists of fast spin-echo T1- and T2-weighted images obtained in a single breath hold; multisection, dynamic, fast gradient-echo images obtained in a single breath hold; and contrast material-enhanced images obtained in the arterial-dominant and delayed phases. Hepatocellular carcinoma, with its predominantly arterial blood supply, usually appears hyperintense on arterial-dominant phase images and isointense or hypointense relative to liver parenchyma on delayed-phase images.

SPECT with In-111 autologous platelets to detect residual splenic tissue in two patients with relapsed thrombocytopenia.

In two patients with relapsed thrombocytopenia, the authors used SPECT with In-111 labeled autologous platelets to identify residual splenic tissue after splenectomy. One case involved a previously splenectomized patient with idiopathic portal hypertension, while the other had relapsed chronic idiopathic thrombocytopenic purpura (ITP). In both patients, SPECT showed a higher In-111 uptake in the splenic tissues compared with planar images.

Ventilation abnormalities in obstructive airways disorder: detection with pulmonary dynamic densitometry by means of spiral CT versus dynamic Xe-133 SPECT.

Purpose: To evaluate pulmonary dynamic densitometry (PDD) by means of spiral computed tomography (CT) for detection of ventilation abnormalities in obstructive airways disorders compared with dynamic xenon-133 single photon emission CT.

Materials And Methods: Eight-second spiral CT was performed during two to three respiratory cycles in six healthy volunteers, 19 patients with airways disorder, and six patients with restrictive lung disease. The data sets were reconstructed as 36 1-second temporally overlapping images at 0.

Competitive enzyme immunoassay for bovine growth hormone.

We developed an enzyme immunoassay (EIA) for bovine GH (bGH) which is based on indirect competitive immunoassay in culture medium from a bovine pituitary cell culture. 40 microliters cell culture samples (or bGH standard) and bGH antibody (rabbit anti-bGH) were added to the 96 well microplate coated with secondary antibody (Goat anti-rabbit IgG), and incubated for 24 h at 37 degrees C. Biotin-label bGH was added and incubated further for 24 h at 37 degrees C, and biotinylated bGH was linked with streptoavidin-peroxidase.

Inhibition of GH releasing factor (GRF)-induced GH secretion by intraruminal infusion of volatile fatty acids (VFA) in sheep.

A VFA mixture solution containing acetate, propionate and butyrate (the molar ratio of acetate, propionate and n-butyrate = 61.7:24.3:14.

[A case of bilateral adrenal neuroblastomas detected by bone scintigraphy].

A 7-month-old girl, who had been resected the left adrenal neuroblastoma 20 days ago, underwent bone scintigraphy with 90mTc-HMDP to survey bone metastases. The bone scan demonstrated avid uptake in the right adrenal gland, in which 123I-MIBG also accumulated. However, the degree of 123-I-MIBG uptake in the right adrenal gland was not necessary higher compared to that in the normal adrenal glands in 7 patients after resection of hemilateral neuroblastomas.

Evaluation of the radiosensitizing effects of RK28 intravenous, intraarterial, and intratumoral injections on the rabbit VX2 tumor system.

Purpose: To evaluate the differences in the radiosensitizing effects of intravenous (i.v.) injection, intraarterial (i.

Hepatic parenchymal hyperperfusion abnormalities detected with multisection dynamic MR imaging: appearance and interpretation.

On arterial-dominant-phase images in multisection dynamic MR imaging, early-enhancing areas that are perfusion abnormalities rather than tumor deposit are sometimes encountered. The purpose of this article was to determine the frequency, location, and appearance of these hepatic parenchymal hyperperfusion abnormalities and to discuss possible causes of these abnormalities. Multisection dynamic MR images obtained in 415 patients with suspected hepatobiliary diseases were reviewed for the presence of hyperperfusion abnormalities.

Is it possible to differentiate malignant mediastinal nodes from benign nodes by size? Reevaluation by CT, transesophageal echocardiography, and nodal specimen.

Study Objective: To reevaluate whether it is possible to reliably differentiate malignant mediastinal lymph nodes from benign nodes by size, and to determine the frequency of metastases to normal-sized mediastinal lymph nodes that directly affects the sensitivity for detecting malignant mediastinal lymph nodes (N2 nodes) on CT.

Design: Prospective study of patients with non-small cell lung cancer.

Setting: Department of Radiology and First Department of Surgery, Yamaguchi University School of Medicine.

Coronary angiographic finding of thrombus in the left atrial appendage.

Purpose: The value of coronary angiography in the diagnosis of thrombus in the left atrial appendage (LAA) was retrospectively analyzed.

Material And Methods: The study covers 34 patients in whom coronary angiography showed coronary neovascularity in LAA with coronary artery-left atrial fistula indicating LAA thrombus. All 34 patients underwent transthoracic echocardiography within one week of coronary angiography.