Voxel-based analysis and multivariate pattern analysis of diffusion tensor imaging study in anti-NMDA receptor

Yanli Liang1, Luhui Cai1, Xia Zhou1

  • 1Department of Neurology, The First Affiliated Hospital of Guangxi Medical University, Nanning, China.

Neuroradiology
|December 1, 2019
PubMed
Abstract

Insights

Brain white matter changes in anti-N-methyl-D-aspartate receptor encephalitis patients are linked to cognitive deficits. Diffusion tensor imaging and machine learning accurately classify patients based on these white matter alterations.

Area of Science:

  • Neuroscience
  • Neurology
  • Radiology

Background:

  • Anti-N-methyl-D-aspartate (anti-NMDA) receptor encephalitis is an autoimmune disorder that can cause significant neurological and psychiatric symptoms.
  • Cognitive deficits, particularly in memory, executive function, and perception, are common residual symptoms following treatment.
  • Understanding the underlying brain changes, especially in white matter (WM), is crucial for diagnosing and managing these deficits.

Purpose of the Study:

  • To investigate white matter (WM) alterations in patients with anti-NMDA receptor encephalitis.
  • To explore the relationship between WM changes and cognitive function in these patients.
  • To assess the utility of multivariate pattern analysis (MVPA) using diffusion tensor imaging (DTI) metrics for classifying patients.

Main Methods:

  • Fifteen patients with anti-NMDA receptor encephalitis and fifteen healthy controls underwent DTI and the Montreal Cognitive Assessment (MoCA).
  • Fractional anisotropy (FA) and mean diffusivity (MD) values were extracted from various brain regions.
  • MVPA was employed to classify patients based on FA and MD, calculating regional weights.

Main Results:

  • Patients exhibited reduced FA in the right middle temporal gyrus and right precuneus, and increased MD in the left medial temporal gyrus and left frontal lobe compared to controls.
  • Cognitive impairments were noted in executive function, fluency, delayed recall, and visual perception.
  • FA in the right precuneus correlated positively with MoCA and fluency scores; MD in the left frontal lobe correlated negatively with MoCA scores. MD in the left medial temporal gyrus correlated positively with delayed recall. MVPA achieved 70-80% accuracy in classification.
  • Key brain regions identified by MVPA (temporal lobe, cerebellum, hippocampus) showed overlapping importance for both FA and MD.

Conclusions:

  • White matter microstructural changes, detectable by DTI, are significantly associated with cognitive impairments in anti-NMDA receptor encephalitis.
  • MVPA using FA and MD demonstrates robust classification capabilities, aiding in understanding disease-specific patterns.
  • These findings offer insights into the pathophysiology of persistent cognitive deficits and highlight DTI as a valuable tool for assessment.