MR findings of the osteofibrous dysplasia.
OBJECTIVE
The aim of this study was to describe MR findings of osteofibrous dysplasia.


METHODS
MR images of 24 pathologically proven osteofibrous dysplasia cases were retrospectively analyzed for a signal intensity of the lesion, presence of intralesional fat signal, internal hypointense band, multilocular appearance, cortical expansion, intramedullary extension, cystic area, cortical breakage and extraosseous extension, abnormal signal from the adjacent bone marrow and soft tissue and patterns of contrast enhancement.


RESULTS
All cases of osteofibrous dysplasia exhibited intermediate signal intensity on T1-weighted images. On T2-weighted images, 20 and 4 cases exhibited heterogeneously intermediate and high signal intensity, respectively. Intralesional fat was identified in 12% of the cases. Internal low-signal bands and multilocular appearance were observed in 91%. Cortical expansion was present in 58%. Intramedullary extension was present in all cases, and an entire intramedullary replacement was observed in 33%. Cortical breakage (n = 3) and extraosseous mass formation (n = 1) were observed in cases with pathologic fractures only. A cystic area was observed in one case. Among 21 cases without a pathologic fracture, abnormal signal intensity in the surrounding bone marrow and adjacent soft tissue was observed in 43% and 48%, respectively. All cases exhibited diffuse contrast enhancement.


CONCLUSIONS
Osteofibrous dysplasia exhibited diverse imaging features ranging from lesions confined to the cortex to more aggressive lesions with complete intramedullary involvement or perilesional marrow edema.
Department of Radiology, College of Medicine, The Catholic University of Korea, Seoul 137-701, Korea.
Joon-Yong
JY
Jung
Department of Radiology, College of Medicine, The Catholic University of Korea, Seoul 137-701, Korea.
Won-Hee
WH
Jee
Department of Radiology, Seoul National University College of Medicine, Seoul 110-744, Korea.
Sung Hwan
SH
Hong
Department of Radiology, Seoul National University Bundang Hospital, Seongnam 463-707, Korea.
Heung Sik
HS
Kang
Department of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul 138-736, Korea.
Hye Won
HW
Chung
Department of Radiology, Kyung Hee University College of Medicine, Seoul 130-872, Korea.
Kyung-Nam
KN
Ryu
Department of Radiology, College of Medicine, The Catholic University of Korea, Seoul 137-701, Korea.
Jee-Young
JY
Kim
Department of Radiology, College of Medicine, The Catholic University of Korea, Seoul 137-701, Korea.
Soo-A
SA
Im
Department of Radiology, College of Medicine, The Catholic University of Korea, Seoul 137-701, Korea.
Jeong-Mi
JM
Park
Department of Radiology, College of Medicine, The Catholic University of Korea, Seoul 137-701, Korea.
Mi-Sook
MS
Sung
Department of Radiology, College of Medicine, The Catholic University of Korea, Seoul 137-701, Korea.
Yeon-Soo
YS
Lee
Department of Radiology, Korea University College of Medicine, Seoul 136-705, Korea.
Suk-Joo
SJ
Hong
Department of Pathology, College of Medicine, The Catholic University of Korea, Seoul 137-701, Korea.
Chan-Kwon
CK
Jung
Department of Orthopedic Surgery, College of Medicine, The Catholic University of Korea, Seoul 137-701, Korea.
Yang-Guk
YG
Chung
D000273:Adipose Tissue / Q000473:pathology; D000293:Adolescent; D000328:Adult; D001848:Bone Diseases, Developmental / Q000175:diagnosis* / Q000473:pathology; D002675:Child, Preschool; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D012189:Retrospective Studies
Bone neoplasms; Magnetic resonance imaging; Osteofibrous dysplasia