Prediction of postoperative pulmonary function using perfusion magnetic resonance imaging of the lung

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 (313) 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 = 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 == 0.68). Conclusion: Perfusion MRI is suitable for semiquantitative evaluation of regional pulmonary perfusion.