Female 45 years old Reason: composition of right 1st MTP mass History: right bunion with overlying painful mass/cyst Small osteophytes are present at the MTP and interphalangeal joints indicating moderate osteoarthritis. Bone marrow signal is normal. Lis franc ligament is intact. No abnormal tendinous tears or thickening.Along the medial aspect of the first MTP there is an oval well-circumscribed fluid attenuation lesion measuring approximately 8 x 6 mm (series 8, image 17). This cystic lesion demonstrates homogeneous T2 hyperintense signal without internal septation. On postcontrast imaging, there is a thin wall of enhancement. This cyst does not involve the extensor tendon but closely associated with the collateral ligament. This likely represents a ganglion cyst which appears to be arising adjacent to the collateral ligament, likely extending from the joint space. Minimal subcutaneous soft tissue edema is present surrounding this cyst.
Ganglion cyst medial to the MTP adjacent to the collateral ligament likely extending from the joint space.