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The most common case study deficiencies noted by the ICAMRL application reviewers are image artifacts, patient motion and poor SNR. Artifacts are common in magnetic resonance imaging and a quality technologist must be able to assess the cause, and implement measures to reduce or eliminate the artifact through proper patient screening and instruction. Artifacts have a unique appearance; the source needs to be identified and corrective measures taken to minimize or eliminate them. Although it is sometimes impossible to eliminate artifacts, ignoring their presence and cause is not acceptable. If image quality or the anatomy in question is affected, steps must be taken to address the problem directly. Artifacts noted on images submitted for accreditation automatically lead to a delay accreditation decision if they interfere with the anatomy in question. In addition, artifacts are often a red flag to the application reviewers that either the technologist is not trained properly or that the system may need maintenance.

Some common causes of artifacts include, but are not limited to:

• Patient touching the coil or bore of the magnet
• Metal implanted in the patient (i.e., surgical rods)
• Metal on the patient (i.e., keys, jewelry)
• FOV too large for the anatomy imaged
• FOV too small
• RF leak in the room
• Coil problems
• Light fixtures
• Air gaps
• Motion

With fast gradient imaging techniques and breath hold sequences, motion on imaging should be a rare event. Surprisingly, many applicant laboratories submit cases with motion. It is imperative for the technologist to ensure that the patient is comfortable during the scan. Many patients are anxious about the test itself or about the results. To help eliminate patient motion, it is important to watch and listen to the patient during the exam. Additional applications to help reduce motion include gating and respiratory compensation techniques, and the placement of saturation bands to help eliminate pulsatile flow and breathing motion artifacts.

One of the most important aspects of magnetic resonance imaging is patient positioning and coil selection. The "golden" rule in magnetic resonance imaging is to place the anatomy in the center of the coil and place the coil in the center of the magnet. Pads or material should be placed in between the patient's body and any surface that touches the coil or magnet bore. This will help eliminate high signal fat artifacts. The coil selected is based on the anatomy to be imaged and will increase the signal to noise ratio.

In closing, the goal of a magnetic resonance technologist should be to produce the best images possible by manipulating sequence parameters to achieve good SNR; eliminate artifact generation; control patient motion through communication, breath hold sequences, saturation band use, respiratory compensation and gating techniques. As true imaging professionals know, the performance of a quality magnetic resonance examination is much more than placing a patient in the magnet, selecting a protocol and hitting the start button. Much like the art connoisseur that can detect the difference between a reproduction and an authentic Picasso, an imaging professional can recognize quality imaging when it is presented. When preparing to submit an accreditation application to the ICAMRL, laboratories are encouraged to focus on the concept that each selected case study should be representative of the laboratory's best work. Because this aspect of the application carries such significant weight in the final decision, extreme care should be used in selecting cases that best demonstrate the level of patient care being provided by the applicant facility.

For the current list of Case Study Requirements, visit the ICAMRL website at www.icamrl.org/icamrl/accreditation/casestudies.htm.