OBJECTIVETo evaluate the clinical values of spiral CT imaging postprocessing techniques.

METHODSTotally 167 patients with known or suspected abnormalities of thorax (including small pulmonary emboli, primary and metastatic tumours, diffuse lung diseases, bronchiectasis and emphysema) underwent spiral CT of their thorax. We reconstructed images by using different postprocessing techniques (MPR, MIP, SSD, VR, STS and VE). Images after postprocessing were reviewed in conjunction with axial CT scans by three readers with specific focus on their diagnostic and therapeutic efficiency. Judgement was reached by consensus.

RESULTSCompared with axial CT scans, image presentation after postprocessing (a) corrected interpretive errors in 15 cases; (b) raised diagnostic confidence by providing supplemental diagnostic and/or morphologic information in 57 cases; (c) assisted the accurate location of complicated sites in 9 cases; (d) played a major role in therapy planning in 75 cases; and (e) was not associated with diagnostic superiority in 11 cases.

CONCLUSIONPostprocessing of spiral CT data can represent a useful complement to axial CT in most patients with thoracic diseases and should be a routine part of radiological practice.