Toluene abuse: physical basis for hypointensity of the basal ganglia on T2-weighted MR images.
OBJECTIVE
To explain the hypointensity in the basal ganglia on T2-weighted magnetic resonance (MR) images of brains of toluene abusers.


METHODS
Eight patients with histories of toluene abuse underwent MR imaging. A bilayered model of dipalmitoylphosphatidylcholine (DPPC; 100 mmol/L concentration) and varying concentrations of toluene was formed. The DPPC control and toluene-mixed bilayers underwent MR imaging. T1 and T2 were measured as a function of toluene and lipid concentrations.


RESULTS
T2-weighted images of patients who had abused toluene showed marked hypointensity in the thalami and moderate hypointensity in the basal ganglia. Measurements of the DPPC-toluene phantom indicated that toluene-tainted lipid bilayers dramatically shortened T2 and had little effect on T1. By comparison, DPPC itself had little discernible effect on either T1 or T2.


CONCLUSIONS
This model suggests that partitioning of toluene into the lipid membranes of cells in cerebral tissue may be responsible for the hypointensity of basal ganglia noted on T2-weighted MR images of brains of toluene abusers.
Department of Radiology, University of Arizona, Tucson 85724.
E
E
Unger
A
A
Alexander
T
T
Fritz
N
N
Rosenberg
J
J
Dreisbach
D000328:Adult; D001479:Basal Ganglia / Q000473:pathology*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008875:Middle Aged; D008961:Models, Structural; D019966:Substance-Related Disorders / Q000473:pathology*; D014050:Toluene
D014050:Toluene