Fibromatosis colli in both heads of the sternocleidomastoid muscle: Sonographic findings

Objective: To describe the sonographic findings of fibromatosis colli if both heads of the sternocleidomastoid muscle are involved. Materials and methods: In a retrospective study nine examinations for fibromatosis colli were collected from 67 sonographic studies of the neck. The examinations were analyzed for involvement of one or both heads of the sternocleidomastoid muscle. Results: Both heads of the sternocleidomastoid muscle were involved in six of nine patients. Conclusion: Involvement of both heads of the sternocleidomastoid muscle seems to be frequent in fibromatosis colli. Knowledge of the sonographic appearance of this condition will facilitate its recognition and will preclude an incorrect diagnosis.