Phantom

A phantom or imaging phantom is a highly specialized object utilized in medical imaging for quality control, equipment calibration, dosimetry and education. The use of the name is used interchangeably for each object despite their differences.

There are two main type of phantom, anthropomorphic and calibration.

Anthropomorphic phantom

Anthropomorphic phantoms are objects that simulate patients, made of materials with similar tissue characteristics to normal biological organisms. Due to their availability and likeness to real patients, anthropomorphic phantoms can be used for a variety of tasks. Rather than image multiple patients, anthropomorphic phantoms can be used for trial and error to asses the optimal use of radiation such as in new protocols or image reconstruction techniques . On that same premise, anthropomorphic phantoms can be utilized for teaching staff different imaging techniques or exposure factors.  Recent advancements in 3D printing technology are improving the development of anthropomorphic phantoms to better mimic patient tissue .

Calibration phantom

A calibration phantom is often a cylinder, or plate with densities of already known values. They are utilized in quality control to ensure images are reconstructing the imaged phantom to the correct density values. Deviation from these values can indicate a need for imaging equipment service.