Computed tomography of the normal pulmonary hilum.

The detection of pulmonary hilar abnormalities using computed tomography (CT) requires a detailed understanding of cross-sectional hilar anatomy. Many lobar and segmental bronchi are identifiable on CT scans and form the basis for interpreting hilar CT. Large pulmonary artery and venous branches within the hilum produce relatively constant hilar contours and were identified using dynamic CT scans following the bolus injection of contrast medium. At several levels on the right and at one level on the left, the posterior hilum is devoid of vessels.