Direct voxel-based comparisons between grey matter shrinkage and glucose hypometabolism in chronic alcoholism

Abstract

Alcoholism is associated with widespread brain structural abnormalities affecting mainly the frontocerebellar and the Papez's circuits. Brain glucose metabolism has received limited attention, and few studies used regions of interest approach and showed reduced global brain metabolism predominantly in the frontal and parietal lobes. Even though these studies have examined the relationship between grey matter shrinkage and hypometabolism, none has performed a direct voxel-by-voxel comparison between the degrees of structural and metabolic abnormalities. Seventeen alcoholic patients and 16 control subjects underwent both structural magnetic resonance imaging and 18 F-2-fluoro-deoxy-glucosepositron emission tomography examinations. Structural abnormalities and hypometabolism were examined in alcoholic patients compared with control subjects using two-sample t-tests. Then, these two patterns of brain damage were directly compared with a paired t-test. Compared to controls, alcoholic patients had grey matter shrinkage and hypometabolism in the fronto-cerebellar circuit and several nodes of Papez's circuit. The direct comparison revealed greater shrinkage than hypometabolism in the cerebellum, cingulate cortex, thalamus and hippocampus and parahippocampal gyrus. Conversely, hypometabolism was more severe than shrinkage in the dorsolateral, premotor and parietal cortices. The distinct profiles of abnormalities found within the Papez's circuit, the fronto-cerebellar circuit and the parietal gyrus in chronic alcoholism suggest the involvement of different pathological mechanisms.

Relations between cognitive and motor deficits and regional brain volumes in individuals with alcoholism

“…Brain volume deficits in this sample of chronic alcoholics reflected those observed in the full group of alcoholics from which this sample was selected (Pfefferbaum et al 2018;Sullivan et al 2018) and are consistent with reports from previous imaging studies (Cardenas et al 2007;Ritz et al 2016){Makris et al 2008}. Using atlas-based quantitative MRI, this study demonstrated that the alcoholics examined herein had volume deficits in frontal, cingulate, insular, parietal, and hippocampal regions as observed in the larger sample from which this group was drawn (Sullivan et al 2018){Pfefferbaum 2018}.…”

“…Two imaging studies lent further evidence of frontal lobe involvement in alcoholism. A positron emission tomography (PET) study provided a direct voxel-by-voxel comparison between the degrees of structural and metabolic abnormalities in 17 alcoholics and identified gray matter shrinkage in nodes of the frontostriatal, frontocerebellar, and frontolimbic circuits, including frontal and cerebellar cortices, cingulate gyrus, thalamus, and hippocampus (Ritz et al 2016). A longitudinal structural MRI study on 222 individuals with alcohol dependence reported frontal regional volumes that were most extensively affected, including the precentral, supplementary motor, and medial cortices (Sullivan et al 2018).…”

Accelerated aging and motor control deficits are related to regional deformation of central cerebellar white matter in alcohol use disorder

“…Neuroradiologically, the mainstay of studies of uncomplicated alcoholism concurs with neuropathological findings, especially of white matter involvement . Quantitative MRI studies report tissue shrinkage typically in the anterior superior vermis, involving lobules I‐V with additional sites of volume deficit in the white matter of the cerebellar hemispheres (; for review,), also exacerbated by common alcoholism‐related concomitant complications …”

The thalamus in drug addiction: from rodents to humans

“…While disagreements between structural and functional neuroimaging methods exist [85,86], structural and functional neuroimaging results are associated [87][88][89][90][91]. Despite some negative findings [92][93][94][95], lower thalamic grey matter volumes in drug-dependent individuals, across drugs of abuse including alcohol, cocaine, nicotine, methamphetamine, opioids, cannabis and synthetic cannabinoids [95][96][97][98][99][100][101][102][103][104][105][106][107], have been reported. Such decreased grey matter volume in the thalamus (as well as the amygdala and cortical regions including the PFC) is associated, for example, with increased craving for methamphetamine [102], more lifetime tobacco use [108], more years of substance use in polysubstance users [109], and shorter abstinence length in alcohol users [110].…”