Osteoid osteoma--the CT vessel sign.

Objective: To evaluate whether the presence of a feeding vessel in proximity to osteoid osteomas of long bones on multidetector CT (MDCT) can be an adjuvant clue for the diagnosis of osteoid osteoma.

Materials And Methods: Forty-nine CT scans of patients with radiological and clinical diagnosis of osteoid osteoma of long bones and a control group of 20 CT scans of patients with cortical-based lesions other then osteoid osteoma were analyzed. Two radiologists evaluated the CT images in consensus for the presence of a blood vessel in the same axial slices in which the nidus of osteoid osteoma was seen and to determine the incidence.