Presentation
Chronic right pelvic pain. Chest radiograph and upper abdominal ultrasound were normal.
Patient Data
There is a large well-defined multivesicular cystic mass (13 x 7 x 6 cm) of intramuscular location in the right iliacus muscle composed of numerous cysts of variable sizes of low signal on T1, high signal on T2 and intercystic solid matrix of isosignal to the muscles on T1 and slightly high signal on T2. No enhancement of the cystic wall or the solid matrix on postcontrast sequences.
Case Discussion
MRI features of a hydatid cyst of the iliacus muscle.
Musculoskeletal hydatid infections are a very rare form of hydatid disease. The most common locations are vertebrae/para-vertebral soft tissue, pelvis, femur and soft tissue of the lower limb. The contractile nature and high lactic acid level of the muscles diminish the growth process of the oxygen-dependant cysts.