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White-matter abnormalities in brain during early abstinence from methamphetamine abuse.

Tobias MC, O'Neill J, Hudkins M, Bartzokis G, Dean AC, London ED - Psychopharmacology (Berl.) (2010)

Bottom Line: The methamphetamine group exhibited lower FA in right prefrontal white matter above the AC-PC plane (11.9% lower; p = 0.007), in midline genu corpus callosum (3.9%; p = 0.019), in left and right midcaudal superior corona radiata (11.0% in both hemispheres, p's = 0.020 and 0.016, respectively), and in right perforant fibers (7.3%; p = 0.025).FA in left midcaudal superior corona radiata was correlated with depressive and generalized psychiatric symptoms within the methamphetamine group.These effects are already present during the first weeks of abstinence from methamphetamine and are linked to psychiatric symptoms assessed during this period.

View Article: PubMed Central - PubMed

Affiliation: Semel Institute for Neuroscience and Biobehavioral Studies, University of California Los Angeles, Los Angeles, CA, USA.

ABSTRACT

Background: Previous studies revealed microstructural abnormalities in prefrontal white matter and corpus callosum of long-term abstinent chronic methamphetamine abusers. In view of the importance of the early abstinence period in treatment retention, we compared 23 methamphetamine-dependent subjects abstinent from methamphetamine for 7-13 days with 18 healthy comparison subjects. As certain metabolic changes in the brain first manifest after early abstinence from methamphetamine, it is also possible that microstructural white-matter abnormalities are not yet present during early abstinence.

Methods: Using diffusion tensor imaging at 1.5 T, fractional anisotropy (FA) was measured in prefrontal white matter at four inferior-superior levels parallel to the anterior commissure-posterior commissure (AC-PC) plane. We also sampled FA in the corpus callosum at the midline and at eight bilateral, fiber-tract sites in other regions implicated in effects of methamphetamine.

Results: The methamphetamine group exhibited lower FA in right prefrontal white matter above the AC-PC plane (11.9% lower; p = 0.007), in midline genu corpus callosum (3.9%; p = 0.019), in left and right midcaudal superior corona radiata (11.0% in both hemispheres, p's = 0.020 and 0.016, respectively), and in right perforant fibers (7.3%; p = 0.025). FA in left midcaudal superior corona radiata was correlated with depressive and generalized psychiatric symptoms within the methamphetamine group.

Conclusions: The findings support the idea that methamphetamine abuse produces microstructural abnormalities in white matter underlying and interconnecting prefrontal cortices and hippocampal formation. These effects are already present during the first weeks of abstinence from methamphetamine and are linked to psychiatric symptoms assessed during this period.

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Related in: MedlinePlus

DTI FA whole-brain color map of an experimental subject. In the left, an axial-oblique (at the AC–PC plane) section. The white box in left prefrontal white matter (PFWM) indicates the boundaries of a 3-mm deep 9 × 9-mm2 slab across which FA values were sampled and averaged in postprocessing. A similar average was obtained for the right PFWM. In the right, a parasagittal section of the same color map depicts the position of the four parallel prefrontal white-matter slabs (white bars) located at the level of the AC–PC plane (C), 6 mm below (D), and 6 (B) and 9 (A) mm above. Left and right PFWM FA averages were obtained at each level
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Fig1: DTI FA whole-brain color map of an experimental subject. In the left, an axial-oblique (at the AC–PC plane) section. The white box in left prefrontal white matter (PFWM) indicates the boundaries of a 3-mm deep 9 × 9-mm2 slab across which FA values were sampled and averaged in postprocessing. A similar average was obtained for the right PFWM. In the right, a parasagittal section of the same color map depicts the position of the four parallel prefrontal white-matter slabs (white bars) located at the level of the AC–PC plane (C), 6 mm below (D), and 6 (B) and 9 (A) mm above. Left and right PFWM FA averages were obtained at each level

Mentions: Two methods were used to extract regional FA from the scan data. The first method was similar to one described before (Chung et al. 2007). FA values were taken from and averaged across each of four axial-oblique (AC–PC-aligned) slab VOIs in each frontal lobe. Each VOI was 3 × 3 DTI voxels square in-plane and 1 voxel deep. Each VOI was centered within prefrontal white matter and positioned to avoid contamination from neighboring gray matter. Within these constraints, the VOI position yielding the highest average FA value was selected. The four DTI slabs on which the VOIs were selected were as follows: (1) the lowest slab was centered 6 mm below the AC–PC plane, (2) the next slab was at the AC–PC plane, (3) the third was 6 mm above the AC–PC plane, and (4) the final slab was 9 mm above (Fig. 1). Special care was taken to exclude the corpus callosum, identified with the help of FA color maps indicating the direction of fiber tracts.Fig. 1


White-matter abnormalities in brain during early abstinence from methamphetamine abuse.

Tobias MC, O'Neill J, Hudkins M, Bartzokis G, Dean AC, London ED - Psychopharmacology (Berl.) (2010)

DTI FA whole-brain color map of an experimental subject. In the left, an axial-oblique (at the AC–PC plane) section. The white box in left prefrontal white matter (PFWM) indicates the boundaries of a 3-mm deep 9 × 9-mm2 slab across which FA values were sampled and averaged in postprocessing. A similar average was obtained for the right PFWM. In the right, a parasagittal section of the same color map depicts the position of the four parallel prefrontal white-matter slabs (white bars) located at the level of the AC–PC plane (C), 6 mm below (D), and 6 (B) and 9 (A) mm above. Left and right PFWM FA averages were obtained at each level
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2819660&req=5

Fig1: DTI FA whole-brain color map of an experimental subject. In the left, an axial-oblique (at the AC–PC plane) section. The white box in left prefrontal white matter (PFWM) indicates the boundaries of a 3-mm deep 9 × 9-mm2 slab across which FA values were sampled and averaged in postprocessing. A similar average was obtained for the right PFWM. In the right, a parasagittal section of the same color map depicts the position of the four parallel prefrontal white-matter slabs (white bars) located at the level of the AC–PC plane (C), 6 mm below (D), and 6 (B) and 9 (A) mm above. Left and right PFWM FA averages were obtained at each level
Mentions: Two methods were used to extract regional FA from the scan data. The first method was similar to one described before (Chung et al. 2007). FA values were taken from and averaged across each of four axial-oblique (AC–PC-aligned) slab VOIs in each frontal lobe. Each VOI was 3 × 3 DTI voxels square in-plane and 1 voxel deep. Each VOI was centered within prefrontal white matter and positioned to avoid contamination from neighboring gray matter. Within these constraints, the VOI position yielding the highest average FA value was selected. The four DTI slabs on which the VOIs were selected were as follows: (1) the lowest slab was centered 6 mm below the AC–PC plane, (2) the next slab was at the AC–PC plane, (3) the third was 6 mm above the AC–PC plane, and (4) the final slab was 9 mm above (Fig. 1). Special care was taken to exclude the corpus callosum, identified with the help of FA color maps indicating the direction of fiber tracts.Fig. 1

Bottom Line: The methamphetamine group exhibited lower FA in right prefrontal white matter above the AC-PC plane (11.9% lower; p = 0.007), in midline genu corpus callosum (3.9%; p = 0.019), in left and right midcaudal superior corona radiata (11.0% in both hemispheres, p's = 0.020 and 0.016, respectively), and in right perforant fibers (7.3%; p = 0.025).FA in left midcaudal superior corona radiata was correlated with depressive and generalized psychiatric symptoms within the methamphetamine group.These effects are already present during the first weeks of abstinence from methamphetamine and are linked to psychiatric symptoms assessed during this period.

View Article: PubMed Central - PubMed

Affiliation: Semel Institute for Neuroscience and Biobehavioral Studies, University of California Los Angeles, Los Angeles, CA, USA.

ABSTRACT

Background: Previous studies revealed microstructural abnormalities in prefrontal white matter and corpus callosum of long-term abstinent chronic methamphetamine abusers. In view of the importance of the early abstinence period in treatment retention, we compared 23 methamphetamine-dependent subjects abstinent from methamphetamine for 7-13 days with 18 healthy comparison subjects. As certain metabolic changes in the brain first manifest after early abstinence from methamphetamine, it is also possible that microstructural white-matter abnormalities are not yet present during early abstinence.

Methods: Using diffusion tensor imaging at 1.5 T, fractional anisotropy (FA) was measured in prefrontal white matter at four inferior-superior levels parallel to the anterior commissure-posterior commissure (AC-PC) plane. We also sampled FA in the corpus callosum at the midline and at eight bilateral, fiber-tract sites in other regions implicated in effects of methamphetamine.

Results: The methamphetamine group exhibited lower FA in right prefrontal white matter above the AC-PC plane (11.9% lower; p = 0.007), in midline genu corpus callosum (3.9%; p = 0.019), in left and right midcaudal superior corona radiata (11.0% in both hemispheres, p's = 0.020 and 0.016, respectively), and in right perforant fibers (7.3%; p = 0.025). FA in left midcaudal superior corona radiata was correlated with depressive and generalized psychiatric symptoms within the methamphetamine group.

Conclusions: The findings support the idea that methamphetamine abuse produces microstructural abnormalities in white matter underlying and interconnecting prefrontal cortices and hippocampal formation. These effects are already present during the first weeks of abstinence from methamphetamine and are linked to psychiatric symptoms assessed during this period.

Show MeSH
Related in: MedlinePlus