From the Research
MRI enhancement in multiple sclerosis typically lasts for 6-12 weeks after contrast administration, as shown in the most recent and highest quality study 1. This duration can vary depending on several factors, including the severity of inflammation, individual patient characteristics, and treatment status. The enhancement occurs when gadolinium contrast material leaks through the disrupted blood-brain barrier at sites of active inflammation, highlighting new or active MS lesions. Most active lesions show enhancement for about 4 weeks on average, with some resolving within 2 weeks while others may remain enhanced for up to 3 months in rare cases. This temporary enhancement period represents the acute inflammatory phase of lesion formation, which eventually subsides as the blood-brain barrier repairs itself. Understanding this timeline is important for clinicians when scheduling follow-up MRIs to monitor disease activity and treatment response in MS patients. Some studies suggest that the use of contrast agents in MRI scans for MS patients may not always be necessary, and that non-contrast MRI scans can be used to monitor disease progression in some cases 2. However, the most recent and highest quality study 1 provides the most accurate estimate of the duration of MRI enhancement in MS. Key factors that influence the duration of enhancement include:
- Severity of inflammation
- Individual patient characteristics
- Treatment status
- MRI acquisition parameters, such as the use of high-sensitivity protocols 1. Overall, the duration of MRI enhancement in MS is an important consideration for clinicians when monitoring disease activity and treatment response.