Related Experiment Video
Updated: Feb 14, 2026

Cochlear Implantation in the Guinea Pig
Published on: June 15, 2018
Cochlear implants and 1.5 T MRI scans: the effect of diametrically bipolar magnets and screw fixation on pain
Ingo Todt1, Grit Rademacher2, Gloria Grupe3
1Department of Otolaryngology, Head and Neck Surgery, Unfallkrankenhaus Berlin, Warenerstr.7, 12683, Berlin, Germany. todt@gmx.net.
Background:
The probability that a patient will need an MRI scan at least once in a lifetime is high. However, MRI scanning in cochlear implantees is associated with side effects. Moreover, MRI scan-related artifacts, dislodging magnets, and pain are often the most frequent complications. The aim of this study was to evaluate the occurrence of pain in patients with cochlear implant systems using 1.5T MRI scans.
Methods:
In a prospective case study of 10 implantees, an MRI scan was performed and the degree of pain was evaluated by a visual analog scale. Scans were performed firstly with and depending on the degree of discomfort/pain, without a headband. Four of the cochlear implants contained a screw fixation. Six cochlear implants contained an internal diametrically bipolar magnet. MRI observations were performed with a 1.5 T scanner.
Results:
MRI scans were performed on all patients without causing any degree of pain, even without the use of a headband.
Conclusion:
Patients undergoing 1.5 T MRIs with devices including a diametrically bipolar magnet or a rigid implant screw fixation, experienced no pain, even without headbands.
Related Concept Videos
Radiological Investigation II: MRI and Ventilation Perfusion Scan
Magnetic Resonance Imaging (MRI) and Ventilation Perfusion Scans are two radiological investigations that offer detailed diagnostic images of the body, particularly lung structures.
MRI
MRI uses magnetic fields and radiofrequency signals to distinguish between normal and abnormal tissues. This technology provides a more detailed diagnostic image than CT scans, enabling it to characterize pulmonary nodules, stage bronchogenic carcinoma, and evaluate inflammatory activity in...
Screw: Problem Solving
To evaluate the...
Self-Locking Screw
A square-threaded screw jack carrying a load is considered self-locking if the screw retains its position even after the moment applied to it is removed.
Bipolar Disorder
Frictional Forces on Screws
A jack with a square-threaded screw is a mechanical device used to lift heavy loads by applying a force at its handle. When the force is applied, the screw turns, raising the load. The screw can...
Bipolar Junction Transistor

