Introduction
Magnetic resonance imaging (MRI) is an important modality in diagnostics and treatment follow-up. A common non-open MRI camera consists of a tunnel approximately 1.6 m long and 0.6 m in diameter surrounded by the magnet 1-2. The patient lies isolated in the camera during the examination which lasts for approximately 30-60 minutes. The noise level during the examination is high, between 65 and 95 decibels depending on the MRI equipment and procedure, thus ear protection is used during the examination. Although noninvasive, MRI may therefore be perceived as unpleasant and stressful 3. For example, experiences of fear and a threat of losing self-control have been described during MRI 4-5, and 14% of patients experience severe anxiety and fear in MRI 6. Several studies reported that up to 15% of patients terminate their MRI due to anxiety and feelings of claustrophobia during the examination7-10. Features of MRI equipment and its strange environment have been described as sources of distress4-6.
Various measures aiming to alleviate patient discomfort have been investigated 11; for example, premedication9, relaxation exercises 12-14, hypnosis 15, a visit prior to MRI16, extensive oral information and counselling14, 17, and a telephone contact or a video demonstration of the procedure prior to the examination18-19. Most of these interventions are time consuming and rather complex to provide in clinical practice. Using a questionnaire to identify whether a person has claustrophobia has been suggested 20-21, and persons with claustrophobia may then be examined in an open magnet 22-24 or receive premedication 9. However, open magnets have limitations 25 and using sedatives may be inconvenient for outpatients due to side effects, and if sedatives are given intravenously, monitoring of the patient also needs to be considered26.
Lack of information can worsen anxiety at MRI 27-28. However, patients’ knowledge of how MRI is conducted is usually scarce and the source of information is often relatives 29, which points to the need for accurate and standardized pre-scanning information. For example, written information before an MRI has been found needed and welcomed by patients 3, 30, and an information booklet would be a simple and inexpensive means to ameliorate the discomfort that might be experienced. It has been stressed that such written patient information should contain several types of information, i.e., procedural (how the examination/treatment is carried out), behavioral (how the patient can cooperate), and sensory (what the patient may experience) information 31.
However, the evidence regarding the potential effects of a simple intervention such as an information booklet delivered to the patient prior to the MRI examination is scarce. One non-randomized study used written information but in combination with other measures16 and found reduced anxiety levels during scanning. Another non-randomized study failed to demonstrate any differences in anxiety or satisfaction with the information between groups receiving standard vs. extended pre-scan written information, although motion artefacts in the MRI images were fewer in the latter group32.
The aim of this randomized single-blind placebo-controlled trial was to investigate the effects of a standardized information booklet on patient anxiety and satisfaction with information in connection with MRI. Specifically, the following hypotheses were investigated.
  1. A standardized information booklet on MRI decreases patient anxiety prior to and during MRI scanning.
  2. A standardized information booklet on MRI increases patient satisfaction with information about the procedure.