A well-defined heterogeneous signal intensity lesion is seen in the periarticular location along the posterior and superior aspects of the left hip joint.
This lesion shows T2 hyperintense solid areas which show contrast enhancement, non-enhancing cystic areas as well as a T2 hypointense focus along its posterior aspect which shows blooming on GRE images. The lesion is slightly hyperintense to the muscle on T1WI. The lesion is in contact with the medial aspect of the greater trochanter and superior surface of the neck of the left femur as well as the lateral aspect of the left acetabulum. However, there is no evidence of erosions or marrow infiltration of these bones.
The left sciatic nerve is seen to course along the medial aspect of the lesion. The lesion
appears to be mildly compressing the left sciatic nerve against the ischial tuberosity
medially. There is no obvious evidence of nerve infiltration.