II. Contraindications: General
- Ferromagnetic Intracranial Aneurysm clips (non-ferromagnetic clips are MRI safe)
- Metallic foreign body in eye or brain
- Cochlear Implant (MRI Conditional)
- TENS unit
III. Contraindications: Legacy Cardiac Devices
- Precautions
- Even non-legacy, "MRI compatible" devices (e.g. loop recorders, Pacemaker) require planning for MRI
- Device reps, implanting specialty and radiology are often consulted even for "MRI compatible" devices
- Background
- Newer cardiac devices are defined as MRI Conditional (whereas legacy devices do not carry the designation)
- Adverse Effects related to legacy devices in MRI
- Power-On Reset Event (most common, may reset functional mode)
- Altered sensing and pacing thresholds
- Generator failure
- Device battery depletion
- False Positive sensing that triggers antitachycardia pacing or electrical Defibrillation shocks
- Safety
- Legacy devices may undergo MRI in some centers with safety protocols and electrophysiology available
- Legacy cardiac devices appear to be safe in MRI if safety protocols in place
- Affected devices
- Legacy Pacemakers
- Legacy Implantable Defibrillator (AICD)
IV. Safety: Allowed metal objects
- Coronary stents
- Surgical Clips
V. Safety: Pregnancy
- MRI appears safe in pregnancy
- However, Gadolinium is associated with Stillbirths and a small increased risk of rheumatologic or inflammatory conditions
- Ray (2016) JAMA 316(9):952-61 +PMID:27599330 [PubMed]
VI. Precautions
- Magnetic field is always on
- Do not enter scan room with a metallic object
- Stethoscope
- Tuning fork
- Reflex hammer