Value of multiplanar reformations (MPR) in multislice spiral CT.

Purpose: To evaluate the quality of multiplanar reformations (MPR) of multi detector spiral-CT (MD-CT) data sets of the chest based on anatomic criteri a. Methods: 90 patients with suspected or known diseases of the lung parenc hyma underwent thoracic MD-CT with l-mm collimation. Axial scans were recon structed with l-mm slice width and 0.6-mm reconstruction increment. Coronal and sagittal MPRs were reconstructed with 3, 5 and 8 mm thickness from the axial scans. Three blinded readers rated image quality based on several an atomic criteria and the presence of different artifacts using a 5-point sca le. The scores for MPRs were compared with those of 5-mm thick axial scans. Results: All anatomical structure were equally well depicted on MPRs as on axial scans with very good interobserver correlation (kappa 0.69-0.76). On ly the lung parenchyma directly adjacent to the heart and the great vessels were visualized with limited quality due to cardiac pulsation artifacts. A dvantages of sagittal MPRs include the sharper delineation of interlobar fi ssures and thus improved anatomic localization of a lesion. Coronal reforma tions also offer improved anatomic orientation in comparison with 5-mm axia l scans. A slice thickness of 5 mm for MPRs yielded best results. Conclusio ns: MPRs allow an unrestricted assessment of the lung. Sagittal and coronal reformations improve the topographical visualization of chest anatomy.