Leeds test object
A Leeds Test Object or Leeds Phantom is a quality assurance tool for a medical imaging device. These devices are mostly concerned with x-ray imaging techniques such as fluoroscopy, digital radiography, mammography and computed tomography (CT) although Leeds phantoms also exist for some aspects of radiotherapy QA and for other techniques such as MRI.
The test object or phantom allows a radiographer or medical physicist to check the consistency of the image quality performance of the imaging device. The main aspects of image quality which are analysed are CONTRAST resolution, spatial resolution or modular transfer function and geometric accuracy.
First manufactured in 1955, Leeds Test Objects have become world renowned as a clinical standard for establishing the correct operating performance of X-ray machines following their adoption for clinical use by the U.K. Health Service (NHS).