AJR. American journal of roentgenology
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AJR Am J Roentgenol · Jan 2004
Comparative StudyIntracranial dural arteriovenous fistulas: evaluation with combined 3D time-of-flight MR angiography and MR digital subtraction angiography.
The purpose of this study was to compare the diagnostic utility of 3D time-of-flight (TOF) MR angiography and MR digital subtraction angiography in patients with angiographically proven moderate- to high-flow intracranial dural arteriovenous fistula. ⋯ A protocol including both 3D TOF MR angiography (source images) and MR digital subtraction angiography allowed the diagnosis of moderate- to high-flow dural arteriovenous fistula. In addition, cortical venous drainage was reliably noted in a small subset of patients.
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AJR Am J Roentgenol · Jan 2004
Comparative StudyDynamic perfusion MRI versus perfusion scintigraphy: prediction of postoperative lung function in patients with lung cancer.
The purpose of this study was to determine the capability of dynamic perfusion MRI as an alternative to pulmonary perfusion scintigraphy for prediction of postoperative lung function in patients with lung cancer. SUBJECTS AND METHODS. Sixty patients with lung cancer (35 men, 25 women) underwent dynamic perfusion MRI, perfusion scintigraphy, and preoperative and postoperative pulmonary function tests (forced expiratory volume in 1 sec [FEV(1)]). Perfusion MRIs were obtained with a 3D turbo field-echo sequence (TR/TE, 2.7/0.6; flip angle, 40 degrees; matrix, 128 x 96) using a 1.5-T scanner. Regional blood flow was calculated from the signal intensity-time curves after bolus injection of contrast medium on MRI (Q(MRI)) and uptake ratios of radioisotope on perfusion scintigraphy (Q(PS)). Postoperative lung functions predicted by MRI (FEV(1,MRI)) and perfusion scintigraphy (FEV(1,PS)) were calculated from preoperative FEV(1) and regional Qs. To determine the capability of MRI as an alternative to scintigraphy, we evaluated correlations and the limits of agreement between predicted FEV(1,MRI) and postoperative FEV(1) and between predicted FEV(1,PS) and postoperative FEV(1). ⋯ Dynamic perfusion MRI is a feasible alternative to pulmonary perfusion scintigraphy for predicting postoperative lung function in patients with lung cancer.
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AJR Am J Roentgenol · Jan 2004
Comparative StudyDetection of malignant hepatic tumors with ferumoxides-enhanced MRI: comparison of five gradient-recalled echo sequences with different TEs.
The purpose of our study was to compare the detectability of malignant hepatic tumors on ferumoxides-enhanced MRI using five gradient-recalled echo sequences at different TEs. ⋯ In the detection of malignant hepatic tumors, gradient-recalled echo sequences at 8 msec showed the highest sensitivity and had an A(z) value and lesion-to-liver contrast-to-noise ratio comparable with values from gradient-recalled echo sequences at 6 and 10 msec and fast spin-echo sequences.