(CAD) 'Computer aided detection' or 'computer assisted diagnosis' systems are tools to improve the efficiency and workflow in medical imaging procedures. The aim of CAD is to increase the diagnostic accuracy of screening procedures by using a computer system to locate abnormalities, improve image management, correct patient movement and assist the radiologists in the interpretation and analysis of data-intensive studies. Typical applications include the tumor detection in mammography, breast MRI, colonography, and lung imaging. Newer applications like prostate MRI are under investigation.

See also MR Guided Interventions, Breast MRI and Hybrid Imaging.

Possible MR guided interventions are breast MRI, liver and bone biopsies. Open MRI is advantageous to guide interventional procedures because this type of MRI scanner provides a better patient access.
Before the MRI guided biopsy is started, all the necessary precautions ensuring normal sterile and safe conditions for an intervention have to be performed. This includes the special safety issues concerning MRI surroundings and special equipment, like non-magnetic biopsy needles, localization tools (e.g. wires to mark lesions prior to surgery with breast MRI guidance) etc.

See also 5 Gauss Line, Contraindications, Low Field MRI, MR Compatibility, Magnetic Resonance Guided Focused Ultrasound and Computer Aided Detection.

MR images can be manipulated for evaluation in various ways. Postprocessing includes: Subtraction, addition, rotation, inversion, multiplanar reconstruction (MPR), maximum intensity projection (MIP), etc.
Subtraction is particularly useful in contrast enhanced MRI examinations (for example breast MRI, brain MRI). The pre contrast images are subtracted from the images after an injection of contrast agents (sometimes also called dye) for a better tumor detection.

See also Computer Aided Detection