Magnetic resonance imaging features and classification of intraspinal echinococcosis.

Objective: This study aimed to investigate the magnetic resonance imaging (MRI) features and classification of echinococcosis of the spinal canal. Methods: The clinical manifestations and MRI findings and classification of 19 patients diagnosed with intraspinal echinococcosis over 10 years (2011-2020) were retrospectively analyzed. Results: The mean age of the nine males and 10 females was 39 years (range 28-65 years). Among these, the number of cases with thoracic, lumbar, sacral, thoracolumbar, and lumbosacral, cervical, and lumbar segments was nine (47 %), five (26 %), one (5 %), one (5 %), two (11 %), and one (5 %) cases, respectively. Furthermore, 13 cases (69 %) involved adjacent vertebral bodies, accessories, and surrounding soft tissues. The lesion was confined to the intramedullary, extramedullary subdural, extramedullary epidural, and multiple spaces in one (Type I) (5 %), four (Type II) (21 %), one (Type III) (5 %), and thirteen (69 %) cases, respectively. Moreover, nine cases (47 %) had a history of hydatid disease in the spine or other tissues. The clinical manifestations were chest and lumbosacral pain in 18 cases (95 %) and chest and lumbosacral pain accompanied by lower limb dysfunction in four cases (21 %). The MRI revealed different sizes of T1WI low-signal and T2WI high-signal vesicles with a "grape-like" appearance, with 16 cases (84 %) showing low signals on the edge of the cyst wall. Conclusion: Intraspinal echinococcosis is rare, even in endemic areas. However, intraspinal echinococcosis should be considered when there is a history of echinococcosis in other sites or when there are clear MRI characteristics for the disease.