A 62-year-old man scheduled for brain MRI discloses that he had a cerebral aneurysm clipped 10 years ago. The operative notes cannot confirm the clip material. What is the MOST appropriate course of action?
- A Proceed with MRI using a low field strength scanner of 0.5 T or less
- B Proceed with MRI after removing all metallic jewellery and monitoring the patient closely
- C Defer MRI until the clip model is identified and confirmed as MR conditional or safe ✓
- D Replace MRI with a gadolinium-enhanced CT angiogram regardless of clinical indication
Correct answer: C. Defer MRI until the clip model is identified and confirmed as MR conditional or safe
Explanation
An unidentified intracranial aneurysm clip is a potential absolute contraindication because a ferromagnetic clip can torque or migrate in the static magnetic field, causing catastrophic vascular injury. Scanning must be deferred until the exact clip model is verified against manufacturer MR safety documentation. Reducing field strength does not make an unknown ferromagnetic clip acceptable, and substituting another modality is a secondary decision made only after the MRI is deemed unsafe.
Reference: Grainger & Allison's Diagnostic Radiology, 7th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.