[Computerized tomography in diagnosis of lung metastases: improvement with the spiral technique]

Computed tomography is the imaging modality of choice for detection or exclusion of pulmonary metastases. In most cases these are spheric, multiple, bilateral, and located in the peripheral areas of the middle and lower fields of the lungs. Differential diagnosis of solitary pulmonary nodules is difficult. Evaluating whether they are malignant or benign is insufficient despite the application of multiple CT criteria. Spiral computed tomography acquiring an imaging volume in a breathhold has led to significant improvement in the sensitivity of detecting pulmonary nodules. Imaging protocols are presented, and the influence of the different parameters is discussed. Although not all pulmonary metastases may be detected with spiral computed tomography, it is the most important examination when considering pulmonary metastasectomy. Computed tomography is the imaging modality of choice when monitoring pulmonary metastases during systemic therapeutic regimens by measuring all nodules or "indicator lesions."