Helical CT assessment in hilar cholangiocarcinoma: correlation with surgical and pathologic findings.

OBJECTIVE: Our goal was to assess the usefulness of helical CT in the presurgical evaluation of hilar cholangiocarcinoma. CONCLUSION: Helical CT aids in tumor localization and in assessment of parenchymal, biliary intrahepatic, and portal involvement in hilar cholangiocarcinoma. However, helical CT is not effective in the assessment of biliary extrahepatic, arterial, and lymph node involvement.

Abdominal aortic aneurysms: assessment with gadolinium-enhanced time-of-flight coronal MR angiography (MRA).

A prospective study was performed to evaluate the efficacy of a gadolinium-chelate-enhanced MR angiography (MRA) using a coronal acquisition in the preoperative assessment of aneurysms of the abdominal aorta (AAA). Twenty patients with AAA were explored with MR using a two-dimensional (2D) time-of-flight MRA technique with a coronal acquisition, before and after intravenous administration of 0.1 mmol/kg of a gadolinium-chelate. Gadolinium-chelate-enhanced MRA with a coronal acquisition decreased deleterious saturation effects within aorta and iliac arteries in 16 of 20 patients (80%) and improved the overall quality of the images of the upper and lower parts of the AAA (i.e. extent of the aneurysm). Furthermore, gadolinium-chelate-enhanced MRA with a coronal acquisition allowed a better differentiation between slow flow and mural thrombus. Gadolinium-chelate-enhanced MRA had a sensitivity of 100% and a specificity of 96% for evaluation of renal artery involvement, and a sensitivity of 93% and a specificity of 100% for iliac artery involvement. The results of this study show that gadolinium-chelate-enhanced MRA obtained with a coronal acquisition is efficacious for the preoperative assessment of AAA.

Assessment of vascular involvement with magnetic resonance angiography (MRA) in Pancoast syndrome.

The purpose of this study was to evaluate the diagnostic value of MRA in determining vascular involvement in bronchogenic carcinoma with Pancoast syndrome. Six patients with Pancoast syndrome were investigated preoperatively by means of MRA. Following standard spin-echo MR imaging in the axial and coronal planes, two successive two-dimensional (2D) time-of-flight acquisitions were obtained in the axial plane, the first with venous, the second with arterial presaturation. MRA data were compared to angiographic data in four cases, and to surgical findings in all six cases. MRA demonstrated displacement (n = 2) and encasement (n = 2) of subclavian and/or brachiocephalic arteries, and encasement or occlusion of subclavian and/or right brachiocephalic vein (n = 3). Close correlation between MRA, angiography and surgery was obtained. These preliminary results suggest that MRA is a noninvasive diagnostic method complementary to MR imaging for detecting vascular involvement in bronchogenic carcinoma with Pancoast syndrome.

Enlarged mediastinal lymph nodes in bronchogenic carcinoma: assessment with dynamic contrast-enhanced MR imaging. Work in progress.

PURPOSE: To determine whether dynamic contrast material-enhanced magnetic resonance (MR) imaging can help differentiate between malignant and benign mediastinal lymph nodes (MLNs) in bronchogenic carcinoma. MATERIALS AND METHODS: Nine patients with biopsy-proved lung carcinoma underwent dynamic contrast-enhanced MR imaging before undergoing thoracic surgery. MR studies included spin-echo, electrocardiographically gated axial and coronal sequences and transaxial gradient-echo breath-hold sequences, which were performed after administration of a bolus of gadoterate meglumine. The enhancement curves were established on the basis of mean signal intensities from regions of interest at the level of tumor and the enlarged MLN. MR images were compared with pathologic specimens obtained at surgical resection. RESULTS: Metastatic MLNs exhibited their peak enhancement at 60-80 seconds, with a slow decrease until 6 minutes. Granulomatous and anthracotic lymph nodes displayed a slight enhancement, with no peak within 6 minutes (P < .01). CONCLUSION: Dynamic contrast-enhanced MR images may provide informative data about the nature of enlarged MLNs in the preoperative assessment of lung carcinoma. Further studies are needed to investigate its usefulness in clinical practice.

Bronchiectasis: assessment by thin-section CT.

To assess the accuracy of computed tomography (CT) in the evaluation of bronchiectasis, we performed thin-section CT in 36 patients with clinical findings suggestive of this diagnosis. CT was performed with 1.5-mm section thickness and 10-mm intersection spacing. Bilateral (eight patients) and unilateral (28 patients) bronchograms were obtained. CT and bronchographic findings were correlated in 44 lungs. In 15 lungs no bronchiectasis was observed on CT scans and bronchograms. In 25 lungs both examinations accurately indicated the presence and extent of bronchiectasis. In two lungs the extent of disease was underestimated on CT, which failed to indicate bronchiectasis in one segment of the affected lobe. In one case CT findings suggested focal bronchial disease, but the lung was misinterpreted as not bronchiectatic; the bronchogram showed cylindric bronchiectasis. In one case CT disclosed cylindric bronchiectasis in a lobe that was bronchographically normal, but in this case the bronchogram was probably misinterpreted as false negative. In two cases lung findings were better visualized on CT scans than on bronchograms. It is concluded that thin-section CT is an accurate procedure in the recognition of bronchiectasis.