Imaging features of central nervous system paragonimiasis in children based on a large-scale case series study

Central nervous system (CNS) paragonimiasis is relatively uncommon and its imaging findings have not been fully described in the limited literature. Our aim was to investigate the comprehensive imaging features of CNS paragonimiasis based on a large-scale case series study, with an emphasis on the unreported imaging findings.

The clinical and imaging data of 206 pediatric patients with CNS paragonimiasis were continuously collected from 1181 cases of paragonimiasis in the past 12 years at the Children's Hospital of Chongqing Medical University (China). All patients underwent CT and/or MR scans. The lesion location and the comprehensive imaging features including the previously unreported imaging signs were reviewed and analyzed.

The incidence of paragonimiasis involving the CNS was 17.4% (206/1181), with intracranial and intraspinal involvement accounting for 94.7% (195/206) and 5.3% (11/206) respectively. Imaging features of intracranial lesions included hemorrhage (79.5%, 155/195), ring-shaped lesions (63.6%, 124/195), pseudoaneurysms (17.4%, 34/195), meningeal lesions (19.5%, 38/195), and the unreported pure patchy edema (4.1%, 8/195), which was characterized by the absence of combined other typical signs and by its absorption with short-term follow-up. Imaging features of intraspinal lesions included the extradural granuloma (11/11) and the unreported intramedullary lesions (4/11), which were characterized by ring-shaped enhancement and invariably accompanied by the extradural granuloma.

The CNS paragonimiasis has relatively specific imaging features, which are of great value for early diagnosis of the disease. The two previously unreported signs we described will enrich the imaging spectrum of CNS Paragonimiasis.