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Purpose: To assess semiquantitatively the regional distribution of lung perfusion using magnetic resonance (MR) perfusion imaging. Materials and Methods:Subjects were 20 consecutive patients with bronchogenic carcinoma, who underwent MR imaging (MRI) and radionuclide (RN) perfusion scans for preoperative evaluation. Three-dimensional (3D) images of whole lungs were obtained before and 7 seconds after bolus injection of contrast material (5 ml of Gd-DTPA). Subtraction images were constructed from these dynamic images. Lung areas enhanced with the contrast material were measured and multiplied by changes in signal intensity, summed for the whole lung, and the right-to-left lung ratios were calculated. The predicted postoperative forced expiratory volume in 1 second (FEV1) was estimated using MR and RN perfusion ratios. Results:The correlation between perfusion ratios derived from the MR and RN studies was excellent (r ϭ 0.92). Sixteen of 20 patients underwent surgery, and 12 patients had postoperative pulmonary function tests. The predicted FEV1 derived from the MR perfusion ratio correlated well with the postoperative FEV1 in the 12 patients (r ϭ 0.68). Conclusion:Perfusion MRI is suitable for semiquantitative evaluation of regional pulmonary perfusion. PREOPERATIVE EVALUATION OF PATIENTS with bronchogenic carcinoma involves two major considerations: 1) Is the tumor anatomically resectable? and 2) Can the patient tolerate the removal of functioning pulmonary tissue? Computed tomography (CT) and magnetic resonance imaging (MRI) are used routinely to answer the former question (1,2). With respect to the latter, a combination of pulmonary function tests using spirometry and a radionuclide (RN) perfusion scan (RN study) are used to predict postoperative pulmonary function (3,4).Recently the technique of perfusion MRI of the lung has been developed, in which rapid imaging of the first passage of contrast material through the lung is performed after bolus injection into a peripheral vein (5-9). This method has shown promising results with regard to detection of pulmonary emboli (5,6) and low perfusion in chronic obstructive pulmonary disease (COPD) (7). MR perfusion imaging had almost the same sensitivity and specificity for diagnosis of pulmonary perfusion defects as conventional perfusion scintigraphy (6). Hatabu, et al (8) and Levine, et al (9) have demonstrated that MR perfusion imaging can potentially be used to quantitatively evaluate pulmonary perfusion.In the present study, we hypothesized that semiquantitative assessment of pulmonary function may be possible using dynamic contrast-enhanced MRI. We utilized this technique in preoperative evaluation of patients with bronchogenic carcinoma. We calculated postoperative pulmonary function using perfusion ratios derived from MR perfusion imaging and compared the data with that derived from postoperative pulmonary function tests, and also with results of an RN study with 99m Tc-labeled macroaggregated albumin ( 99m Tc-MAA).The quantitative assessment method of pulm...

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Prolene Hernia System surgery is a safe and feasible procedure with low rates of complication, recurrence, and late symptoms.