Subperiosteal abscess in children: scintigraphic appearance.

A subperiosteal abscess is an uncommon complication of osteomyelitis in childhood. Bone scanning is very sensitive for the detection of early skeletal infection; however, a subperiosteal abscess has a different and distinctive scintigraphic appearance. The usual increased tracer uptake of osteomyelitis is overshadowed by the presence of a "cold" lesion on the delayed views, probably due to interruption of the vascular supply of the bone. Early recognition of the condition is important, as surgery is indicated to prevent extensive bone necrosis and chronic osteomyelitis. In suspected osteomyelitis, a central photopenic area is highly suggestive of subperiosteal abscess; when such an area is seen, a computed tomographic (CT) scan can be helpful in planning the surgical approach for drainage. Plain radiographs may be unremarkable even when the bone scan and CT findings are dramatic. Five such cases are presented, and a recommended diagnostic approach is discussed that views the two procedures as complementary.