MRI features of hydatid disease of the spine

Abstract

Objective To analyze the typical MRI findings and to evaluate the value of MRI in the diagnosis of hydatid disease of the spine. Methods This retrospective study consisted of 16 patients with hydatidosis of the spine evaluated with MRI. All patients had surgery with histological diagnosis. MR myelography (MRM) was done in 4 cases, contrast-enhanced scan in 2 cases and perfusion weighted imaging (PWI) in 1 case. X-ray was performed in 8 cases and CT in 5 cases. Results All 16 cases were diagnosed as hydatid disease with multicysts. Hydatid disease involved thoracic spine in 5 cases, lumbar spine in 4 cases, sacrum in 3 cases, lumbnsacral spine in 2 cases and a combination of thoracic, lumbar spine and sacrum in 2 cases. MR imaging showed bone destruction with wedge shaped compression of single or multiple vertebra. The lesions were round in contour with different sizes and involved the bony spinal canal, appendix of vertebra and neighboring soft tissues. Cystic lesions with multiple daughter cysts demonstrated long T1 and long T2 abnormal signal intensity on MR imaging. On T2-weighted images, a hypointense rim was seen. Cystic lesions were better seen on T2 SPIR and MRM. Mild contrast enhancement of these lesions were seen. A single case showed iso-perfusion on PWI. Conclusions MRI can demonstrate hydatid cysts in vertebra, spinal canal, paravertebral and neighboring soft tissue. MRI is a valuable tool in the diagnosis and treatment planning of hydatid disease of the spine. Key words: Hydatid disease; Spine; Magnetic resonance imaging