q-Space Myelin Map: A new myelin-specific imaging technique for treatment monitoring of multiple sclerosis

Objectives

In multiple sclerosis (MS) patients, hyperintense signals on T2-weighted images by magnetic resonance imaging are signs of demyelination; however, T2 signals lack specificity and fail to detect remyelination. For more precise monitoring of MS, a new magnetic resonance imaging technique, q-space Myelin Map (qMM), which specifically identifies myelin, has been developed. This study aimed to explore clinical factors associated with remyelination for different disease-modifying drugs, and to examine the utility and feasibility of qMM in clinical practice.

Methods

Data from sequential patients with relapsing–remitting MS initiating disease-modifying drugs at our center were collected. After treatment initiation, qMM was carried out at 6-month intervals and the resulting images analyzed for evidence of remyelination.

Results

A total of 48 patients with relapsing–remitting MS were included: 22 with dimethyl fumarate, 14 with fingolimod, four with glatiramer acetate and eight with natalizumab. qMM showed qMM-remyelination in 22 patients (45.8%). In natalizumab patients, baseline ages were 33.6 ± 6.9 years (n = 5) and 47.3 ± 5.8 years (n = 3) in patients with or without qMM remyelination, respectively. In dimethyl fumarate patients, the proportion of women was 100% (n = 10) and 50% (n = 12) in patients with or without qMM myelination, respectively.

Conclusions

This exploratory study suggested the potential clinical utility of qMM for visualizing remyelination in MS patients and fine-tuning their pharmacotherapy. Two potential clinical factors promoting qMM-remyelination were identified: female sex with dimethyl fumarate and younger baseline age with natalizumab; a larger prospective study is warranted to confirm these results.