Pediatric skeletal scintigraphy: applications of pinhole magnification

Pinhole magnification scintigraphy is an effective means of evaluating the pediatric skeleton because it provides optimal high-resolution images. This technique is indicated when diagnostic uncertainty persists after high-resolution imaging with parallel hole collimation. Pinhole magnification scintigraphy requires approximately 20 minutes of acquisition time per image and meticulous attention to details such as choice of pinhole insert, collimator positioning, and patient immobilization. However, the technique is superior to planar imaging in demonstrating acute osteomyelitis in bone adjacent to growth centers and epiphyseal involvement that is either primary or the result of local spread of infection. In addition, pinhole imaging has proved highly reliable in the early diagnosis of Legg-Calvé-Perthes disease and is useful in depicting osteonecrosis related to specific causes such as corticosteroid treatment or trauma. Scintigraphic manifestations of femoral head ischemia or infarction and findings indicative of osteomyelitis associated with a hip effusion are well demonstrated with pinhole imaging. This technique also helps characterize osteoid osteomas and may be used intraoperatively to confirm the complete excision of this benign tumor. Finally, pinhole magnification scintigraphy clearly depicts fractures of the femoral neck and allows a high degree of confidence in diagnosing injuries to the small bones of the hands and feet.