Fibromatosis colli of infancy: variability of sonographic appearance.
OBJECTIVE
We describe the variable sonographic appearances of fibromatosis colli, a disease that presents as a mass-like enlargement of the sternocleidomastoid muscle during the first 8 weeks of life.


METHODS
Sonograms and records of 12 infants who presented with a sternocleidomastoid mass or torticollis before they were 12 weeks old were retrospectively reviewed for sonographic features (presence of a mass, diffuse muscle enlargement, and echogenicity), medical history, and follow-up data.


RESULTS
Sonographically, 6 infants had only a mass in the sternocleidomastoid muscle, 2 had a mass with fusiform muscle enlargement, and 4 had only muscle enlargement. Five masses were hyperechoic, and 1 mass was of mixed echogenicity. The 2 masses associated with muscle enlargement were hypoechoic. Three cases of diffuse muscle enlargement were of mixed echogenicity, and 1 was hypoechoic. Unusual variations included (1) a mass split longitudinally into 2 components and (2) a diffusely enlarged muscle with a striated pattern of mixed echogenicity. Follow-up in 10 patients at 4 months and in 7 patients at 6 months showed clinical improvement.


CONCLUSIONS
Fibromatosis colli usually appears sonographically as a hyperechoic mass or diffuse sternocleidomastoid enlargement of mixed echogenicity. Variations in its appearance should not prevent the correct diagnosis as long as the abnormality is intramuscular and adjacent soft tissues are normal.
Department of Diagnostic Radiology, University of Texas M. D. Anderson Cancer Center, Houston 77030, USA.
D G
DG
Bedi
S D
SD
John
L E
LE
Swischuk
D005350:Fibroma / Q000000981:diagnostic imaging*; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D019042:Muscle Neoplasms / Q000000981:diagnostic imaging*; D009334:Neck Muscles / Q000000981:diagnostic imaging*; D012189:Retrospective Studies; D014463:Ultrasonography