CASE 2219 Published on 05.05.2008

Osteolytic process of the mandible: aneurismal bone cyst

Section

Musculoskeletal system

Case Type

Clinical Cases

Authors

Bensmaili M, Le Van An JC, Safa D, Rakhtawane E

Patient

7 years, female

Categories
No Area of Interest ; Imaging Technique CT, MR
Clinical History
A 7-year-old girl presented with history of increasing and decreasing swelling mass of the right mandible over 18 months.
Imaging Findings
A 7-year-old girl presented with history of increasing and decreasing swelling mass of the right mandible over 18 months. Physical examination showed an expansible mass of the right mandible. A panoramic radiograph show an osteolytic radiolucency lesion of the right mandibular ramus. CT scan demonstrated lytic radiolucency , aggressive expansile balooning lesion with cortical destruction, subperiostal reaction and presence of internal trabeculation. MRI showed an expansile inhomogenous fluid-filled lesion with high intensity on T2-weighted images and low-intensity on T-1 weighted images with cortical bowing and septation. A surgical biopsy was performed and confirmed the diagnosis of aneurysmal bone cyst. The follow-up showed stability of the lesion and condensation of the border of the lesion 3 month after the initial CT scan.
Discussion
Mandibular lesions in the pediatric population are unusual. Aneurysmal bone cyst (ABC) of jaws are found more frequently in the mandible than the maxilla but also involved other bone of the face such as the zygoma. ABC generally affects young persons. Radiographs show a unicyst, unilocular, soap bubble, honeycomb, multilocular or moth-eaten radiolucency causing expansion, perforation or destruction of the bony cortices. CT scan showed an expansile ballooning lesion with internal trabeculations with cortical and cortical perforation in some areas. MRI showed an expansile and inhomogenous cystic lesion with cortical bowing , septation and fluid-fluid levels.
The differential diagnosis of radiolucency of mandible include neoplastic and developmental process (odontogenic keratocyst, amenoblastoma, amenoblastic fibroma, amenoblastic fibro odobntoma, myxoma, vascular malformation, central giant cell granuloma) but the main differential diagnosis of ABC is the teleangectatic osteosarcoma and histology is required.
Differential Diagnosis List
Aneurysmal bone cyst
Final Diagnosis
Aneurysmal bone cyst
Case information
URL: https://www.eurorad.org/case/2219
DOI: 10.1594/EURORAD/CASE.2219
ISSN: 1563-4086