Congenital solitary infantile myofibromatosis involving the spinal cord.

Infantile myofibromatosis, a rare mesenchymal disorder that develops in early childhood, is classified by the number of lesions that occur: solitary or multicentric. Involvement of the CNS is unusual in either type. Infantile myofibromatosis in the spine is exceptional, and most published cases represent a secondary invasion. Here, the authors report on an 8-month-old girl presenting with weakness below the ankle and an intraspinal mass extending from T-6 to the conus. The patient underwent only partial surgical removal of the lesion, and the pathology was confirmed as infantile myofibromatosis. After the operation, weakness in the lower extremities gradually improved; however, she could not walk at the time of the final follow-up. On follow-up MRI performed 19 months after the operation, the residual lesion remained unchanged with decreased enhancement.