case_images: PMC11799364_01
case_images: Imaging and Histopathological Features of a Ganglion Cyst in the Medial Gastrocnemius Muscle. (A) Sagittal ultrasound image of a well-circumscribed lesion in the left anterior medial calf of uncertain etiology (arrow). (B) Representative coronal MRI image of the mass showing a hypointense signal on T1-weighted sequences (arrow). (C) Representative coronal MRI image of the mass showing fusiform increased signal at the proximal and distal ends of the mass and a thin rim of peripheral enhancement on T2-weighted sequences (arrow). (D) Representative low-power (x40) H&E staining of the lesion, revealing a thin-walled cyst (hollow arrow) with adjacent skeletal muscle fibers (solid arrow). (E) Representative high-power (x200) H&E staining of the lesion with focal myxoid changes of the fibroconnective tissue. (F) Representative low-power (x100) H&E staining of the lesion with slit-like space formation with no true endothelial, epithelial, or synovial lining.. MRI: magnetic resonance imaging, H&E: hematoxylin and eosin
case_images: cureus-0017-00000077038-i01.jpg
case_images: PMC11799364_01_cureus-0017-00000077038-i01.jpg
case_images: FIG1
case_images: The patient had a previous ultrasound (US) of the lower extremity that showed an ovoid hypoechoic lesion in the left medial calf of uncertain etiology (Figure 1A). The MRI revealed a well-circumscribed mass in the proximal medial head of the left gastrocnemius muscle (Figure 1B, 1C). The cystic wall demonstrated microscopic myxoid changes within the dense collagenous stroma, while the slit-like cystic lumen showed an absence of epithelial or synovial lining, distinguishing it from a true ganglion cyst (Figure 1D-1F).