Osteoid osteoma – imaging
I-V. Malla Houech, H. Houech, V. Hadjidekov
Osteoid osteoma is a benign bone tumours, most commonly affecting patients in the second decade of life. Usually the diagnosis does not impose a diagnostic difficulty. It is manifested by pain in the affected bone, more intense at night, which is relieved by salicylates and radiological findings of the nidus surrounded by a sclerotic bone. The purpose of this paper is to present a case of osteoid osteoma and to show its radiological features on different imaging modalities. We present the case of a 24y.o. male, complaining of a pain, more intense at night in the proximal femur for one year. The patient underwent computer tomography (CT) and magnetic resonance imaging (MR) of the pelvis. CT scan was performed on a 16 slice CT machine. The MRI was carried out on a Hitachi machine (0.4T). Radiographs of the pelvic bones was taken prior to hospitalization and 30 days after the surgical treatment. X-ray of the hip showed osteolytic area in the proximal femur neck on the right side. On CT scan an irregular lesion of osteolysis with a central focus of sclerosis, located in the proximal femur neck on the right side was visualized. MRI revealed T1 hypointensity, fat suppression technique showed hypointense T1 area with surrounding bone oedema. Post-surgical x-ray showed complete ossification of the osteоlytic nidus and no evidence of the lesion. The imaging findings were consistent with osteoid osteoma and the hystological specimen proved the diagnosis. Osteoid osteoma is a benign tumour with a great prognosis. X-ray and CT scan are methods of imaging. Percutaneous radiofrequency ablation is the preferred technique of treatment as it is less traumatic for the patient and the recovery period is shorter.
Key words: OSTEOID OSTEOMA. NIDUS. ОСТЕОСКЛЕРОЗА. CT