MRI shimming and magnetic field correction service
MRI depends on an extremely homogeneous magnetic field. Even small variations in field uniformity can significantly affect image geometry, signal intensity and diagnostic accuracy. Over time, environmental factors, cryogenic behavior and natural magnet drift gradually alter the magnetic field distribution inside the magnet. Many facilities temporarily compensate by adjusting protocols, but these adjustments do not correct the underlying problem.MRI shimming is the process of restoring magnetic field homogeneity, allowing the system to operate within manufacturer specifications and produce consistent, diagnostic-quality images. This condition is commonly observed in superconducting MRI systems from manufacturers such as GE Healthcare, Siemens Healthineers and Philips.
Signs your MRI may require shimming service
Common symptoms
MRI field instability often appears gradually and is commonly mistaken for normal imaging variation. Facilities may temporarily compensate by adjusting protocols or repeating sequences, but the underlying issue remains. Typical signs include image distortion, shading across the field of view, inconsistent fat suppression and signal variation between slices. Technologists may also experience longer scan times or repeated calibrations to obtain acceptable images.
When these conditions persist, shimming restores magnetic field uniformity and allows the system to operate within manufacturer specifications.
What causes this?
Magnetic field instability usually develops gradually. MRI systems are extremely sensitive to environmental and cryogenic variations, and even small changes can affect homogeneity and calibration stability
Image Artifacts
Magnetic field inhomogeneity can create distortions, ghosting and shading across the image, reducing diagnostic quality.
Failed Calibrations
The MRI may be unable to complete tuning or reference scans when the magnetic field is not uniform.
Frequency Drift
Center frequency instability causes scan interruptions and recurring adjustments before exams can start.
Poor Signal Uniformity
Uneven magnetic field distribution leads to signal loss in certain areas of the image, especially in large field-of-view exams.
Our Shimming Process
Our engineers follow a defined technical workflow to diagnose magnetic field behavior, apply the appropriate correction and verify image quality before returning the system to operation. This structured procedure allows accurate diagnosis and predictable correction of magnetic field instability.
Step 1 — Field Analysis and Diagnosis
The procedure begins with magnetic field evaluation. System performance and imaging behavior are reviewed to identify distortion patterns and homogeneity deviation. Calibration data and image characteristics are analyzed to determine the origin of the issue before any adjustment is performed.
Step 2 — Adjustment and Image Validation
After diagnosis, shim adjustments and system calibration are performed to restore field uniformity. The system is recalibrated and validation scans are executed to confirm geometry accuracy, signal consistency and diagnostic image quality before returning the system to clinical operation.
MRI systems and platforms we service
Our engineers support a wide range of superconducting MRI systems. Below are some of the platforms we frequently service.
Siemens
- Siemens Magnetom Altea
- Siemens Magnetom Aera
- Siemens Magnetom Amira
- Siemens Magnetom Avanto
- Siemens Magnetom C!
- Siemens Magnetom Espree
- Siemens Magnetom Essenza
- Siemens Magnetom Sempra
- Siemens Magnetom Skyra
- Siemens Magnetom Sola
- Siemens Magnetom Symphony
- Siemens Magnetom Verio
GE Healthcare
- Signa HDxt
- Signa Excite
- Signa Voyager
- Signa Creator
- Optima MR360
- Optima MR450w
- Signa Brivo
- Discovery MR750
- Signa Architect
Philips
- Intera
- Achieva
- Multiva
- Ingenia
Not every MRI Image problem requires shimming
Some imaging artifacts may originate from other system components. Identifying the correct cause prevents unnecessary interventions and downtime.
Consequences of uncorrected MRI field instability
Unresolved magnetic field instability affects clinical reliability, workflow efficiency and operational performance.
Repeat exams
Patients may need to return due to non-diagnostic images.
Diagnostic uncertainty
Artifacts interfere with accurate clinical interpretation.
Revenue loss
Canceled or delayed exams reduce facility income.
Not sure what your MRI system is experiencing?
Our engineers can review sample images or system behavior and help determine whether shimming or another correction is required before scheduling an on-site visit.
Response typically within one business day.