Centrilobular emphysema (CLE) is a disease defined pathologically. Assessment of the accuracy of high resolution computed tomography (CT) in the diagnosis of centrilobular emphysema has been hampered by a lack of pathologic correlation. We applied high resolution computed tomography to 20 postmortem lung specimens fixed by a method that allows for direct one-to-one pathologic-radiologic correlation. The degree of centrilobular emphysema was assessed radiologically on a visual grading system based on nonperipheral low-attenuation areas. The lungs were then sectioned along the plane of the CT image, and the degree of centrilobular emphysema was graded pathologically by scoring against a panel of standards. A significant correlation (r = 0.91, p less than 0.005) was found between the pathologic grade and the in vitro CT score.