Fibrolipomatous Hamartoma

coronal T1W MRI of fibrolipomatous hamartoma
MR imaging demonstrates fusiform median nerve enlargement which is caused by thickening of nerve bundles and fatty and fibrous proliferation.
The serpiginous low-intensity structures represent thickened nerve fascicles, surrounded by evenly distributed fat of high signal intensity on this T1-weighted image.
A spaghetti-like appearance is seen in the coronal plane.
The median nerve is the most commonly involved nerve
The MR imaging characteristics of fibrolipomatous hamartoma are pathognomonic, obviating the need for biopsy for diagnosis.

Reference: Jain TP, et al. Fibrolipomatous hamartoma of median nerve. Australasian Radiology. 51 Supplement 2:B98-B100, October 2007.

Credit: Dr Aadil Ahmed