Answer:
Monostotic Fibrous Dysplasia of the Clivus
Findings:
Marrow infiltration with expansion of clivus with signal changes in MRI consistent with sclerosis is noted. The lesion is hypointense in TIWI, T2W1, STIR and opposed phase images . No retroclival or sellar soft tissue masses noted. Corresponding CT images reveal increased density of clivus with a hazy ground glass matrix consistent with diagnosis of Fibrous Dysplasia.
Discussion:
Fibrous dysplasia of the clivus is an unrecognized entity with only about 19 cases reported in review of the literature . It is a benign disease most often seen in the first two decades of life and rarely appears in adults FD is a developmental disorder caused by abnormal proliferation and maturation of fibroblasts resulting in replacement of mature bone by structurally weak, immature woven bone . FD may be present in the monostotic (70%) or polyostotic form (30%) with or without AlbrightMcCune syndrome. The monostotic form involves the long bones, with most lesions located in the femur and tibia. The common sites affected by the monostotic form in craniofacial bones are the frontal, sphenoid, ethmoid, orbit, zygoma, maxilla,mandible, and temporal bones. monostotic FD of the clivus is an extremely rare occurrence which is recognized by the characteristic Ground glass fibrous matrix in CT. It has to be distinguished from other clival lesions like chordoma, plasmacytoma , chondrosarcoma and metastasis which appear hypointense in TIWI and hyperintense in T2W1 and Paget`s Disease characterized by Cortical and Trabecular Thickening .
References:
Monostotic Fibrous Dysplasia of the Clivus: Imaging Findings Turkish Neurosurgery 2010, Vol: 20, No: 1, 77-81
Contributed By:
Dr. Babu Peter MD, DNB
Associate Professor, Barnard Institute of Radiology, Chennai
Senior Consultant Radiologist, Aarthi Scans, Chennai
Monostotic Fibrous Dysplasia of the Clivus
Findings:
Marrow infiltration with expansion of clivus with signal changes in MRI consistent with sclerosis is noted. The lesion is hypointense in TIWI, T2W1, STIR and opposed phase images . No retroclival or sellar soft tissue masses noted. Corresponding CT images reveal increased density of clivus with a hazy ground glass matrix consistent with diagnosis of Fibrous Dysplasia.
Discussion:
Fibrous dysplasia of the clivus is an unrecognized entity with only about 19 cases reported in review of the literature . It is a benign disease most often seen in the first two decades of life and rarely appears in adults FD is a developmental disorder caused by abnormal proliferation and maturation of fibroblasts resulting in replacement of mature bone by structurally weak, immature woven bone . FD may be present in the monostotic (70%) or polyostotic form (30%) with or without AlbrightMcCune syndrome. The monostotic form involves the long bones, with most lesions located in the femur and tibia. The common sites affected by the monostotic form in craniofacial bones are the frontal, sphenoid, ethmoid, orbit, zygoma, maxilla,mandible, and temporal bones. monostotic FD of the clivus is an extremely rare occurrence which is recognized by the characteristic Ground glass fibrous matrix in CT. It has to be distinguished from other clival lesions like chordoma, plasmacytoma , chondrosarcoma and metastasis which appear hypointense in TIWI and hyperintense in T2W1 and Paget`s Disease characterized by Cortical and Trabecular Thickening .
References:
Monostotic Fibrous Dysplasia of the Clivus: Imaging Findings Turkish Neurosurgery 2010, Vol: 20, No: 1, 77-81
Contributed By:
Dr. Babu Peter MD, DNB
Associate Professor, Barnard Institute of Radiology, Chennai
Senior Consultant Radiologist, Aarthi Scans, Chennai