Image analysis in multiplanar spiral CT of the lung with MPR and MIP reconstructions

Purpose: To test, whether axial, coronal and sagittal MIP and MPR reconstru ctions of diagnostic quality can be obtained from 1-mm collimation MSCT dat a of the chest for the evaluation of thoracic anatomy and pathology. Materials and Methods: 1-mm collimation MSCT scans were obtained with a pit ch of 6 in an acrylic phantom and in 20 patients. Axial images were reconst ructed with 0.6-mm increment. Multiplanar Reformations (MPRs) and Sliding T hin-Slab Maximum Intensity Projections (STS-MIPs) were reconstructed in axi al, coronal and sagittal planes. Images were printed in lung windows and ev aluated by three readers by using a standardized evaluation scheme. Results: Overall, both methods allowed good visualization of anatomic struc tures. MIP was superior for visualization of the pulmonary arteries (p < 0. 05) while central and peripheral bronchi and the lung parenchyma were bette r depicted on multiplanar reconstructions. A confident diagnosis of thoraci c pathology was feasible using both modalities, however MIPs appeared less usefull for evaluation of gross parenchymal abnormalities, such as pneumoni c infiltrates or fibrotic changes. No significant difference in the degree of motion artifacts were detected between both modalities. Conclusion: MSCT data sets are ideally suited for generating MPR and MIP re constructions. While MIPs are superior for the evaluation of thoracic vesse ls, MPR is advantageous for visualizing central and peripheral bronchi and the pulmonary parenchyma.