White matter microstructure in opiate addiction.
Heroin addiction has been associated with impaired neuronal connectivity and cognitive deficits. One mechanism that potentially explains these findings is alterations in white matter connectivity secondary to chronic opiate use. However, few studies have quantitavely examined white matter deficits in opiate addiction (OA). Here, we investigated white matter microstructure in OA using diffusion tensor imaging (DTI). We performed voxel-wise analysis of fractional anisotropy (FA) in 24 participants with OA and 29 healthy controls. The OA group showed reduced FA in multiple pathways including the corpus callosum, thalamic radiation and inferior longitudinal fasciculus. This FA reduction was mainly the result of increased radial diffusivity (λ(⊥)), indicative of myelin pathology. Longer duration of OA was also associated with axonal diffusivity (λ(1)), most robustly in superior longitudinal fasciculi and right frontal white matter suggesting axonal injury in long-term users. Together, the findings indicate that chronic OA use has widespread and diverse effects on neuronal connectivity and function.
Melbourne Neuropsychiatry Centre, Department of Psychiatry, The University of Melbourne and Melbourne Health, Australia. emrebora@hotmail.com
Emre
E
Bora
Murat
M
Yücel
Alex
A
Fornito
Christos
C
Pantelis
Ben J
BJ
Harrison
Luca
L
Cocchi
Gaby
G
Pell
Dan I
DI
Lubman
D000328:Adult; D016880:Anisotropy; D001931:Brain Mapping / Q000379:methods; D003337:Corpus Callosum / Q000473:pathology*; D056324:Diffusion Tensor Imaging; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D009413:Nerve Fibers, Myelinated / Q000473:pathology*; D009293:Opioid-Related Disorders / Q000473:pathology*