Reduction of Claustrophobia with Short-Bore versus Open Magnetic Resonance Imaging: A Randomized Controlled Trial Judith Enders 1. , Elke Zimmermann 1. , Matthias Rief 1 , Peter Martus 2 , Randolf Klingebiel 3 , Patrick Asbach 1 , Christian Klessen 1 , Gerd Diederichs 1 , Moritz Wagner 1 , Ulf Teichgra ¨ ber 1 , Thomas Bengner 4 , Bernd Hamm 1 , Marc Dewey 1 * 1 Department of Radiology, Charite ´ , Medical School, Humboldt Universita ¨ t zu Berlin and Freie Universita ¨ t Berlin, Berlin, Germany, 2 Department of Biostatistics and Clinical Epidemiology, Charite ´, Medical School, Humboldt Universita ¨t zu Berlin and Freie Universita ¨t Berlin, Berlin, Germany, 3 Division of Neuroradiology, Department of Radiology, Charite ´, Medical School, Humboldt-Universita ¨t zu Berlin and Freie Universita ¨t Berlin, Berlin, Germany, 4 Department of Clinical Psychology, Charite ´, Medical School, Humboldt-Universita ¨t zu Berlin and Freie Universita ¨t Berlin, Berlin, Germany Abstract Background: Claustrophobia is a common problem precluding MR imaging. The purpose of the present study was to assess whether a short-bore or an open magnetic resonance (MR) scanner is superior in alleviating claustrophobia. Methods: Institutional review board approval and patient informed consent were obtained to compare short-bore versus open MR. From June 2008 to August 2009, 174 patients (139 women; mean age = 53.1 [SD 12.8]) with an overall mean score of 2.4 (SD 0.7, range 0 to 4) on the Claustrophobia Questionnaire (CLQ) and a clinical indication for imaging, were randomly assigned to receive evaluation by open or by short-bore MR. The primary outcomes were incomplete MR examinations due to a claustrophobic event. Follow-up was conducted 7 months after MR imaging. The primary analysis was performed according to the intention-to-treat strategy. Results: With 33 claustrophobic events in the short-bore group (39% [95% confidence interval [CI] 28% to 50%) versus 23 in the open scanner group (26% [95% CI 18% to 37%]; P = 0.08) the difference was not significant. Patients with an event were in the examination room for 3.8 min (SD 4.4) in the short-bore and for 8.5 min (SD 7) in the open group (P = 0.004). This was due to an earlier occurrence of events in the short-bore group. The CLQ suffocation subscale was significantly associated with the occurrence of claustrophobic events (P = 0.003). New findings that explained symptoms were found in 69% of MR examinations and led to changes in medical treatment in 47% and surgery in 10% of patients. After 7 months, perceived claustrophobia increased in 32% of patients with events versus in only 11% of patients without events (P= 0.004). Conclusions: Even recent MR cannot prevent claustrophobia suggesting that further developments to create a more patient-centered MR scanner environment are needed. Trial Registration: ClinicalTrials.gov NCT00715806 Citation: Enders J, Zimmermann E, Rief M, Martus P, Klingebiel R, et al. (2011) Reduction of Claustrophobia with Short-Bore versus Open Magnetic Resonance Imaging: A Randomized Controlled Trial. PLoS ONE 6(8): e23494. doi:10.1371/journal.pone.0023494 Editor: Jerson Laks, Federal University of Rio de Janeiro, Brazil Received May 16, 2011; Accepted July 18, 2011; Published August 22, 2011 Copyright: ß 2011 Enders et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Funding: The authors have no support or funding to report. Competing Interests: The following conflicts apply to this study: Dr. Dewey has received grant support from GE Healthcare and Toshiba Medical Systems and lecture fees from Toshiba Medical Systems. Dr. Teichgra ¨ ber has received grant support from Philips Medical Systems. Prof. Hamm has received grant support from GE Healthcare, Siemens Medical Solutions, and Toshiba Medical Systems, and lecture fees from Siemens Medical Solutions. Furthermore, there are institutional master research agreements with Philips Medical Systems, Siemens Medical Solutions, and Toshiba Medical Systems. There are no patents, products in development or marketed products to declare. This does not alter the authors’ adherence to all the PLoS ONE policies on sharing data and materials. * E-mail: marc.dewey@charite.de . These authors contributed equally to this work. Introduction Magnetic resonance (MR) imaging has been rated by leading general internists to be, together with computed tomography (CT), the most important medical innovation of the last 25 years [1]. However, MR imaging can be severely hampered by claustrophobia induced by confinement in the long narrow bore of conventional scanners and further unpleasant aspects of the examination such as scanner noise and vibration [2,3,4,5]. Anxious patients suffer from claustrophobia during MR imaging in up to 35% of all cases [2,6,7], and claustrophobic events can lead to abortion of imaging or require sedation for its completion. This situation decreases diagnostic yield, limits patient acceptance, and reduces workflow. Moreover, conscious PLoS ONE | www.plosone.org 1 August 2011 | Volume 6 | Issue 8 | e23494