Duplex Doppler: identification of cavernous transformation of the portal vein.

Three cases of cavernous transformation of the portal vein are presented, which emphasize the value of duplex Doppler sonography in the recognition of abnormal vascular structures. In all three cases, cavernous transformation was unsuspected; in two, the initial sonographic or CT examinations were interpreted incorrectly. These cases suggest that the combination of characteristic pulsed-Doppler waveforms and the real-time appearance of cavernous transformation is virtually diagnostic.