The brainstem in multiple sclerosis: MR identification of tracts and nuclei damage

Abstract

Objective To evaluate the 3D Fast Gray Acquisition T1 Inversion Recovery (FGATIR) sequence for MRI identification of brainstem tracts and nuclei damage in multiple sclerosis (MS) patients. Methods From april to december 2020, 10 healthy volunteers and 50 patients with remitted-relapsing MS (58% female, mean age 36) underwent MR imaging in the Neuro-imaging department of the C.H.N.O. des Quinze-Vingts, Paris, France. MRI was achieved on a 3 T system (MAGNETOM Skyra) using a 64-channel coil. 3D FGATIR sequence was first performed on healthy volunteers to classify macroscopically identifiable brainstem structures. Then, FGATIR was assessed in MS patients to locate brainstem lesions detected with Proton Density/T2w (PD/T2w) sequence. Results In healthy volunteers, FGATIR allowed a precise visualization of tracts and nuclei according to their myelin density. Including FGATIR in MR follow-up of MS patients helped to identify structures frequently involved in the inflammatory process. Most damaged tracts were the superior cerebellar peduncle and the transverse fibers of the pons. Most frequently affected nuclei were the vestibular nuclei, the trigeminal tract, the facial nerve and the solitary tract. Conclusion Combination of FGATIR and PD/T2w sequences opened prospects to define MS elective injury in brainstem tracts and nuclei, with particular lesion features suggesting variations of the inflammatory process within brainstem structures. In a further study, hypersignal quantification and microstructure information should be evaluated using relaxometry and diffusion tractography. Technical improvements would bring novel parameters to train an artificial neural network for accurate automated labeling of MS lesions within the brainstem.

Lesion follows function: video-oculography compared with MRI to diagnose internuclear ophthalmoplegia in patients with multiple sclerosis

“…Nguyen et al further optimized brainstem imaging with a combination of FGATIR and PD/ T2w sequences to detect MS lesions down to the level of individual tracts and nuclei. [16] The inter-rater reliability of the MRI assessments among the three blinded neuroradiologists was only moderate, with a kappa coefficient of 0.58. While VOG can reliably distinguish the affected side, picking the affected side on MRI was difficult.…”

“…Nguyen et al further optimized brainstem imaging with a combination of FGATIR and PD/T2w sequences to detect MS lesions down to the level of individual tracts and nuclei. [ 16 ]…”

Visualization of small brain nuclei with a high-spatial resolution, clinically available whole-body PET scanner

“…The brainstem nuclei and their neural networks perform a crucial role in regulating basic life-sustaining activities. Numerous previous articles have already reported that brainstem nuclei can be visualized using appropriate MRI sequences such as fast gray matter acquisition T1 inversion recovery, 3D-FLAIR, short tau inversion recovery, and so forth [ 2 , 3 , 23 – 27 ]. In this study, we used T1-MPRAGE and 3D-FLAIR as reference images for the averaged and individual 18 F-FDG PET images to facilitate recognition of which tracer accumulation corresponded to which brainstem nucleus.…”

Selective vulnerability of brainstem and cervical spinal cord regions in people with non-progressive multiple sclerosis of Black or African American and European ancestry

“…24 Prior MRI-based studies have revealed reduced brainstem cross-sectional areas in MS and the impact of involvement in relation to clinical outcomes. 25,26 In addition, newer techniques offer visualization of tracts and nuclei according to myelin density 27 and the importance of the spatial distribution of white matter lesions. 28 Reductions in pontine brain parenchymal fraction in pwMS with sexual dysfunction has also been reported.…”