Lumps and bumps on the head in children: use of CT and MR imaging in solving the clinical diagnostic dilemma.

Lumps and bumps of the scalp are a common presenting complaint in children and often pose a diagnostic dilemma. These lesions can be difficult to image, with evaluation confounded by their small size. However, accuracy in diagnosis is critical because the diagnostic and therapeutic implications can vary significantly. The clinical examination can be helpful in developing the differential diagnosis and the imaging strategy. Often, however, a single imaging study is insufficient, and the radiologist finds it necessary to image with more than one modality to correctly diagnose a lesion and provide adequate information for the surgeon. Radiography and ultrasonography are often the initial screening diagnostic tests, followed by magnetic resonance (MR) imaging or computed tomography (CT) for more detail. Multidetector thin-section CT and thin-section MR imaging with surface coils are beneficial in the work-up of these small lesions of the head and neck. The use of newer MR imaging sequences such as heavily T2-weighted single-shot turbo spin-echo imaging and diffusion-weighted imaging can improve the characterization of difficult lesions. Familiarity with the variety of new imaging tools and techniques that are available can help characterize pediatric head and neck lesions and guide clinical management.