MRI in Multiple Sclerosis: What’s Inside the Toolbox?

Abstract

Summary: Magnetic resonance imaging (MRI) has played a central role in the diagnosis and management of multiple sclerosis (MS). In addition, MRI metrics have become key supportive outcome measures to explore drug efficacy in clinical trials. Conventional MRI measures have contributed to the understanding of MS pathophysiology at the macroscopic level yet have failed to provide a complete picture of underlying MS pathology. They also show relatively weak relationships to clinical status such as predictive strength for clinical progression. Advanced quantitative MRI measures such as magnetization transfer, spectroscopy, diffusion imaging, and relaxometry techniques are somewhat more specific and sensitive for underlying pathology. These measures are particularly useful in revealing diffuse damage in cerebral white and gray matter and therefore may help resolve the dissociation between clinical and conventional MRI findings. In this article, we provide an overview of the array of tools available with brain and spinal cord MRI technology as it is applied to MS. We review the most recent data regarding the role of conventional and advanced MRI techniques in the assessment of MS. We focus on the most relevant pathologic and clinical correlation studies relevant to these measures.

Review of the Clinical Debate Regarding Interventions for Multiple Sclerosis

“…All of these changes correlate with the loss of axons and the occurrence of extensive demyelination and may ultimately be useful markers of neurodegeneration in MS. 66 Because of the different types of lesions, proper detection of MS-related pathology in the brain may require advanced MRI techniques, since evidence suggests that conventional MRI lacks the specificity required for analyzing the underlying pathology and may fail to capture clinically relevant diffuse occult disease affecting both the cerebral white matter and gray matter. 67 Studies using advanced MRI techniques (e.g., magnetization transfer, spectroscopy, diffusion imaging, relaxometry techniques) have provided emerging data that suggest these techniques may result in a more sensitive and specific depiction of clinically relevant underlying pathology. 67 The BECOME trial was a prospective study of 75 patients with CDMS who were randomized to GA injection (n = 39) or IFNβ-1b injection (n = 36) and monitored with monthly MRIs for up to 24 months.…”

“…67 Studies using advanced MRI techniques (e.g., magnetization transfer, spectroscopy, diffusion imaging, relaxometry techniques) have provided emerging data that suggest these techniques may result in a more sensitive and specific depiction of clinically relevant underlying pathology. 67 The BECOME trial was a prospective study of 75 patients with CDMS who were randomized to GA injection (n = 39) or IFNβ-1b injection (n = 36) and monitored with monthly MRIs for up to 24 months. Preliminary results for the primary outcome of the BECOME study-the mean number of combined, active, Gd-enhancing lesions (CAL) per patient over 15 monthswere presented at the European Committee for Treatment and Research in Multiple Sclerosis (ECTRIMS) in 2006.…”

Whole‐brain atrophy assessed by proportional‐ versus registration‐based pipelines from 3T MRI in multiple sclerosis

“…Whole‐brain atrophy is a commonly used research metric to quantify multiple sclerosis (MS) pathology (Neema, Stankiewicz, Arora, Guss, & Bakshi, 2007) and remains one of the strongest correlates and predictors of clinical status (De Stefano et al., 2014). Investigators have applied a myriad of published proprietary and open‐source methods to quantify brain volume loss (Giorgio, Battaglini, Smith, & De Stefano, 2008), leading to heterogeneous segmentation procedures across sites and studies, without any agreed‐upon standard approach (Bermel & Bakshi, 2006).…”

Current and Future Directions in MS Management: Key Considerations for Managed Care Pharmacists

“…Conventional MRI sequences have a relatively weak correlation to clinical status, low sensitivity to grey matter involvement and diffuse white matter damage, and limited ability to predict clinical progression. 35,36 Additionally, prolonged T2 relaxation identifies areas with tissue injury, and Gd-enhancement indicates when there is breakdown of the BBB, but neither quantifies the degree of tissue damage. 37 To address these issues, alternative imaging methodologies are currently being used or are in various stages of clinical development.…”

“…These technologies have also been the subject of several recent comprehensive review articles to which the reader is referred for more details. [35][36][37][38][39][40] It is important to note that the MRI field strength used can have a significant influence on the classification of patients with CIS and MS using current diagnostic criteria. Wattjes et al (2006) evaluated 40 patients with CIS using both 1.5 Tesla (T) and 3.0 T MRI systems.…”