Diagnosis of pulmonary sequestration by spiral CT angiography.

The diagnosis of pulmonary sequestration traditionally requires arteriography to identify abnormal systemic vessels feeding the abnormal portion of the lung. Non-invasive imaging techniques have recently been used to replace arteriography. Conventional computed tomographic (CT) scanning is, however, at a disadvantage because of its inability to obtain multiplanar images. The combination of slip ring CT scanning and computerised three-dimensional reconstruction (spiral CT angiography) can be used to visualise the anatomical detail of a wide range of vessels within the lung. Four cases of pulmonary sequestration are reported which were successfully diagnosed using spiral CT angiography. Spiral CT scanning allows simultaneous imaging of anomalous vessels and lung parenchyma in a single examination and is particularly useful in the diagnosis and assessment of pulmonary sequestration.