THE FREQUENCY, APPEARANCE, AND SIGNIFICANCE OF SPLENIC PERFUSION DEFECTS ON CT ARTERIAL PORTOGRAPHY

Background: The purpose of this study was to determine the frequency, appearance, and significance of splenic perfusion defects on computed tomographic arterial portography (CTAP). Methods: CTAP was performed w ith dynamic scanning at 1-cm increments on 46 consecutive patients pri or to laparotomy. Two readers retrospectively reviewed these studies i n consensus and recorded the number, size, and shape of focal splenic perfusion defects. These defects were later correlated with surgical f indings and at least one of the following imaging modalities: delayed CT 4-6 h after CTAP, intravenously enhanced CT, sonography, or magneti c resonance imaging (MRI). Results: Splenic perfusion defects were pre sent in 14 of 46 CTAP studies (30%), and in seven patients these defec ts were multiple. Most defects were wedge-shaped and peripherally loca ted, although several round defects simulating metastases were also pr esent. The spleen was normal at surgery in all patients, and compariso n imaging revealed only a small splenic infarct in one patient on MRT. Conclusions: Splenic perfusion defects occur in about one-third of pa tients referred for CTAP, are usually wedge-shaped but may be round, a nd should not be interpreted as metastases without other evidence of a space-occupying mass.