MRI with Gadolinium Should Be Performed BEFORE Steroid Administration in Suspected MS
Patients with suspected Multiple Sclerosis should undergo MRI with gadolinium contrast BEFORE receiving any steroid injections to avoid masking inflammatory lesions.
Rationale for Pre-Steroid MRI
Impact of Steroids on MRI Findings
- Steroids significantly reduce the number and volume of gadolinium-enhancing lesions on MRI 1
- Administration of steroids prior to MRI can mask active inflammatory lesions, potentially leading to:
- Missed diagnosis
- Underestimation of disease activity
- Delayed appropriate treatment initiation
Diagnostic Value of Gadolinium Enhancement
- Gadolinium enhancement is crucial for demonstrating dissemination in time (DIT), a key diagnostic criterion for MS 2
- Contrast-enhancing lesions indicate active inflammation with blood-brain barrier disruption 3
- The pattern of enhancement can help differentiate MS from other conditions that mimic MS 2
MRI Protocol Recommendations
Initial Diagnostic MRI
- Brain MRI with gadolinium is mandatory when lesions are seen on T2-weighted sequences 2
- A minimum delay of 5 minutes is recommended between gadolinium injection and T1-weighted sequence acquisition 2
- Standard dose of gadolinium (0.1 mmol/kg body weight) is sufficient for initial diagnostic purposes 2, 4
- Recommended sequences include:
- Axial T1-weighted sequences (pre and post-contrast)
- Axial T2-weighted sequences
- Proton-density or T2-FLAIR sequences
- Sagittal T2-FLAIR sequences 3
Family History Considerations
- The strong family history (mother with stage 4 MS and affected uncle) increases pre-test probability of MS
- This makes proper diagnostic imaging even more critical before initiating treatment
Steroid Treatment Considerations
Timing of Steroids
- Steroids should only be administered after obtaining diagnostic MRI with gadolinium
- Studies show a "consistent reduction" in enhancing lesions following steroid treatment 1
- This effect can persist for weeks, potentially compromising follow-up imaging
Post-Steroid Imaging
- If steroids must be given before MRI (for severe symptoms), note that:
- Sensitivity for detecting active lesions will be reduced
- Additional imaging may be needed later to fully assess disease activity
Clinical Implications
Diagnostic Accuracy
- Proper sequencing (MRI before steroids) increases diagnostic accuracy
- Up to 62% of patients with MS relapse have at least one gadolinium-enhancing brain lesion 5
- Even patients with symptoms outside the brain (spinal cord, optic nerve) frequently show enhancing brain lesions 5
Treatment Planning
- Accurate assessment of disease activity guides appropriate treatment selection
- The number and location of enhancing lesions may have prognostic value
Common Pitfalls to Avoid
- Administering steroids before diagnostic MRI - this can mask inflammatory activity
- Delaying gadolinium-enhanced MRI in patients with suspected MS
- Failing to obtain baseline MRI before treatment initiation
- Underestimating the importance of gadolinium enhancement in initial diagnosis
In conclusion, for a patient with suspected MS and strong family history, the diagnostic pathway should begin with MRI with gadolinium contrast before any steroid treatment is initiated.