Format

Send to

Choose Destination
Sleep. 2012 Mar 1;35(3):345-51. doi: 10.5665/sleep.1692.

White and gray matter abnormalities in narcolepsy with cataplexy.

Author information

1
Department of Neurology, Innsbruck Medical University, Innsbruck, Austria. christoph.scherfler@i-med.ac.at

Abstract

STUDY OBJECTIVES:

The authors applied diffusion-tensor imaging including measurements of mean diffusivity (MD), which is a parameter of brain tissue integrity, fractional anisotropy (FA), which is a parameter of neuronal fiber integrity, and voxel-based morphometry, which is a measure of gray and white matter volume, to detect brain tissue changes in patients with narcolepsy-cataplexy.

DESIGN:

N/A.

PATIENTS:

Patients with narcolepsy-cataplexy (n = 16) and age-matched healthy control subjects (n = 12) were studied.

INTERVENTIONS:

Whole cerebral MD, FA measures, and the volumes of the gray and white matter compartments were analyzed using statistical parametric mapping.

MEASUREMENT AND RESULTS:

Significant MD increases and concomitant FA decreases were localized in the fronto-orbital cortex (P < 0.001) and the anterior cingulate (FA, P < 0.001; MD, P = 0.03) in narcolepsy-cataplexy. Additional MD increases without FA changes were detected in the ventral tegmental area, the dorsal raphe nuclei (P < 0.001), and the hypothalamus (P < 0.01). FA signal decreases were observed in the white matter tracts of the inferior frontal and inferior temporal cortices of narcolepsy-cataplexy patients (P < 0.001). Brain volume loss was evident in focal areas of the inferior and superior temporal cortices (P < 0.001) and the cingulate (P = 0.038).

CONCLUSIONS:

Areas of increased diffusivity in the hypothalamus appear consistent with hypocretinergic cell loss reported in narcolepsy-cataplexy. Signal abnormalities in the ventral tegmental area and the dorsal raphe nuclei correspond to major synaptic targets of hypocretin neurons that were associated with the regulation of the sleep-wake cycle. Brain tissue alterations identified in the frontal cortex and cingulate are crucial in the maintenance of attention and reward-dependent decision making, both known to be impaired in narcolepsy-cataplexy.

KEYWORDS:

Diffusion tensor imaging; narcolepsy with cataplexy; statistical parametric mapping; voxel based morphometry

PMID:
22379240
PMCID:
PMC3274335
DOI:
10.5665/sleep.1692
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for Silverchair Information Systems Icon for PubMed Central
Loading ...
Support Center