Cerebral paragonimiasis in early active stage: CT and MR features

Diagnosis of cerebral paragonimiasis in its early active stage is important because curative chemotherapy is possible. Accordingly, this study was undertaken to evaluate the CT and MR features of early active cerebral paragonimiasis.

We retrospectively reviewed the CT scans (n = 29) and MR images (n = 7) of the brain in 20 patients between 7 and 59 years old who had cerebral paragonimiasis in the early active stage. The diagnosis was based on a positive antibody test by enzyme-linked immunosorbent assay (ELISA) for paragonimiasis in serum and CSF. The diagnosis was confirmed surgically in seven patients.

The most common and characteristic imaging finding was a conglomerate of ringlike enhancing lesions (grape-cluster appearance) with surrounding edema in one cerebral hemisphere in 11 patients (55%). Other nonspecific findings included a solitary ringlike lesion (n = 4) or irregular enhancing lesions (n = 2), localized hemorrhage with (n = 3) or without (n = 2) enhancing lesions, and a poorly defined non-hemorrhagic, nonenhancing lesion (n = 1).

CT and MR findings of clustered ring-enhancing lesions, seen in approximately half of the cases of early cerebral paragonimiasis, are suggestive of cerebral paragonimiasis.