Does bore size matter?—A comparison of the subjective perception of patient comfort during low field (0.55 Tesla) and standard (1.5 Tesla) MRI imaging

Abstract

The purpose of the present study was to evaluate the subjectively perceived patient comfort during magnetic resonance imaging (MRI) examinations and to assess potential differences between a recently introduced low field MRI scanner and a standard MRI scanner. Among other characteristics, the low field MRI scanner differs from the standard MRI scanner by offering more space (wider bore size of 80 centimeter diameter) and producing less noise, which may influence the patient comfort. In total, 177 patients were surveyed after MRI scans with either the low field MRI scanner (n = 91, MAGNETOM Free.Max, Siemens Healthineers) or the standard MRI scanner (n = 86, MAGNETOM Avanto Fit, Siemens Healthineers). Patients rated different aspects of comfort on a 5 point Likert scale: (a) claustrophobia, (b) comfort of the scanner table, (c) noise level and (d) vertigo during the scanning procedure. In terms of claustrophobia and comfort of the scanner table, patients rated both MRI scanners similar (e.g., mean ratings for claustrophobia: standard MRI scanner = 4.63 ± 1.04, low field MRI scanner = 4.65 ± 1.02). However, when asked for a comparison, patients did favor the more spacious low field MRI scanner. In terms of noise level, the low field MRI scanner was rated significantly better (mean ratings: standard MRI scanner = 3.72 ± 1.46 [median 4 = “rather not unpleasant”], low field MRI scanner = 4.26 ± 1.22 [median 5 = “not unpleasant at all”]). Patients did not perceive any significant difference in terms of vertigo between both MRI scanners. The newly developed low field MRI scanner offers constructional differences compared to standard MRI scanners that are perceived positively by patients. Worth highlighting is the significantly lower noise level and the innovative bore diameter of 80 centimeter, which offers more space to the patients.

MPI System with Bore Sizes of 75 mm and 100 mm Using Permanent Magnets and FMMD Technique

“…However, to apply it to humans, technical and scientific issues, such as understanding the impact of strong magnetic fields on humans, developing biocompatible SPIO, and enlarging the equipment, must be resolved [ 20 , 23 ]. Among these, the development of equipment with a bore size large enough for a person to enter (regular: 50–60 cm, wide: 80 cm, based on MRI) is a very important issue [ 24 ], as it must be used in preclinical experiments and tests, such as the development and safety confirmation of SPIO for humans. Based on the papers and presentations published to date, it has been reported that the usual bore sizes of MPI range from 3 cm to 20 cm [ 1 , 14 , 20 ], and thus far, MPI at a level suitable for small animals is common [ 25 ].…”