Name : Morteza
Family :Sanei Taheri
Affiliation : Radiology Department,Shohada Tajrish Hospital,SBMU
Academic Degree: Associate Professor of Radiology
Resident : Ramin Pourghorban
Gender : Male
Age : 22
22 year old male with left knee pain
Imaging Procedures and Findings
AP radiograph (image-1) shows two elongated radiolucent lesions, with surrounding sclerosis in proximal tibial metaphysis. The lateral lesion extends from the closing growth plate to proximal tibial epiphysis. The channel like shape of the lesion suggests Brodie abscess. Axial and reformatted coronal left knee CT images (images 2 and 3) confirm the findings. The lesion is hypo signal on T1WI (imag-4) and hyper signal on T2WI (image-5).MRI images reveals the exact extension of bone marrow edema. Sagittal, coronal and axial proton density fat suppressed images (images 6, 7 and 8 ,respectively) also confirm the findings. Tunnel like extension of the lesion is also clearly depicted on image 7.
Brodie's Abscess. Single or multiple radjolucent abscesses may be evident during subacute or chromc stages of osteomyelitis. they are found characteristically in subacute pyogenic osteomyelitis and are usually of staphylococcal origin.Brodie's abscesses are especially common in children, more typically in boys. In this age group, they appear in the metaphysis, particularly that of the distal or proximal portion of the tibia. In young children and infants, Brodie's abscesses may occur in epiphyses. Radiographs outline radiolucent areas with adjacent sclerosis.This lucent region is commonly located in the metaphysis, where it may connect with the growth plate by a tortuous channel. Radiographic detection of this channel is important; identification of a metaphyseal defect connected to the growth plate by such a tract ensures the diagnosis of osteomyelitis. In an epiphysis, a circular, well-defined osteolytic lesion is seen, which, in the immature skeleton, may border on the chondro-osseous junction or on the physis, where it may extend into the metaphysis. In any skeletal location, computed tomography (CT) or magnetic resonance (MR) imaging can be used to better assess the extent of the abscess and any signs of its reactivation.
Resnick D, Kransdorf M: Bone and Joint Imaging, 3rd ed. Philadelphia: Saunders Elsevier, pp 718-719, 2005.