The third volume of the 3-volume Merrill's Atlas set covers numerous specialty topics. It opens with anatomy and positioning for the nervous and circulatory systems, then gives an overview of sectional anatomy. Other specialty topics include pediatric imaging, mobile radiography, quality assurance, and computer fundamentals. Volume 3 also provides overviews of a variety of special imaging modalities, such as tomography, cardiac catheterization, CT, digital subtraction angiography, MRI, ultrasound, nuclear medicine, bone mineral densitometry, PET, and radiation oncology.