The penumbra sign in subacute osteomyelitis.
The penumbra sign is a characteristic magnetic resonance (MR) feature of subacute osteomyelitis. It can be identified on unenhanced T1-weighted spin echo images as a discrete peripheral zone of marginally higher signal intensity than the central bony abscess cavity and the surrounding lower signal intensity of the reactive new bone and oedema.
Department of Radiology, NHS Trust, MRI Centre, Royal Orthopaedic Hospital, Birmingham, UK. wendy.turner@roh.nhs.uk
A M
AM
Davies
Robert
R
Grimer
D000208:Acute Disease; D003937:Diagnosis, Differential; D006801:Humans; D008279:Magnetic Resonance Imaging; D010019:Osteomyelitis / Q000175:diagnosis*