Changes in the brain directly following alcohol consumption-a study of healthy male individuals, with the use of proton magnetic resonance spectroscopy (1HMRS) and diffusion (DWI).

AIMS: To use proton magnetic resonance spectroscopy (1HMRS) and diffusion weighted imaging (DWI) to identify ethanol in the brain directly after consumption, and examine changes in brain metabolite levels and brain microstructure relative to the duration of time following exposure to alcohol. METHODS: The study involved 44 male volunteers (18-55 years). All brain changes were assessed in the frontal lobes, occipital lobes, basal ganglia and cerebellum, however the detailed analyses focused on the frontal lobes. All participants were examined four times, i.e. before and 0.5-hour, 1 hour and 2 hours after consumption of 150 mL pure vodka (60 g of ethanol). RESULTS: The highest ethanol levels were identified between 0.5 and 1 hour following alcohol intake. There were significant increases in the concentrations of lipids and lactates approximately one hour after alcohol consumption, and the concentration levels were found to normalise during the following two hours. Some statistically insignificant trends of changes were found for tCr, tCho, mI, GABA, Glc, Glx and tNAA. For the DWI and ADC (Apparent Diffusion Coefficient of water) values, the findings showed statistically insignificant decrease and increase, followed by a tendency towards normalisation. Similar associations in changes of metabolite concentrations and DWI and ADC values were found in the other locations investigated in the study. CONCLUSION: A single dose of alcohol as used in this experiment produces increases in lipids and lactates in brain tissues that appear reversible.

Effects of using different software packages for BOLD analysis in planning a neurosurgical treatment in patients with brain tumours.

BACKGROUND: The authors of the present thesis carried out a comparative analysis of three different computer software packages - FSL, SPM and FuncTool - for the processing of fMRI scans. PURPOSE: The aim of the thesis was the analysis of the volume of regions functionally active during the stimulation of the centres evaluated as well as the location of those regions in relation to the tumour boundaries, and then the comparison of the results. MATERIAL AND METHODS: Thirty eight patients with a diagnosed tumour of the left hemisphere, qualified for a neurosurgical operation, underwent fMRI. The functions of speech, motion and sensation were evaluated. Imaging data were processed for all the acquired scans with the use of each of the three software packages assessed. RESULTS: For the FuncTool software package the calculated differences in the distances were several times greater than those calculated using FSL and SPM. The differences in the volume of the functionally active regions derived from the calculations with the use of the FSL and SPM software packages were statistically different for four out of the six functions evaluated. CONCLUSIONS: The conclusions of the analysis in question showed that the FSL and SPM packages could be used interchangeably in the functional mapping of the brain with the purpose of the planning of neurosurgical operations. The FuncTool software package is less precise than FSL and SPM.

Evaluation of changes in biochemical composition of fetal brain between 18th and 40th gestational week in proton magnetic resonance spectroscopy.

INTRODUCTION: The aim of this study is to determine the right 1H MRS spectra of the brain in fetuses of different age, and then to define what metabolic changes occur between 18th and 40th weeks of pregnancy. METHODS: 1H MRS studies of 32 fetuses aged 18-40 gestational weeks were performed, in which the MRI excluded central nervous system malformations. The studied group included 11 fetuses aged 18-25 weeks (the second half of the second trimester), 14 fetuses aged 26-33 weeks (the first half of the third trimester), and seven fetuses aged 34-40 weeks (the second half of the third trimester). The relative ratios of metabolites concentrations to the sum of all metabolites were calculated. RESULTS: Increase in the concentrations of N-acetylaspartate (NAA), Cr, Cho, and myo-inositol (mI) with gestational age is statistically significant. Only increase in Glx is statistically insignificant. In the analyzed period of pregnancy also, an insignificant increase of NAA/Σ and Cr/Σ ratios and a decrease of mI/Σ, Cho/Σ and Glx/Σ ratios were noticed. CONCLUSIONS: Changes in the 1H MRS spectrum are visible with increasing age of the fetus. All studied substances in fetal brain change their concentrations during pregnancy, which may be associated with the synaptic and dendritic development as well as myelination. Knowledge about the chemical changes in the fetal brain can provide valuable information in studies of the mechanisms of pregnancy and fetal development, define steps of brain metabolic development and explain reasons of pathologies.

Sex differences in brain metabolite concentrations in healthy children - proton magnetic resonance spectroscopy study (1HMRS).

PURPOSE: The aim of this 1HMRS study was to define sex-related differences in metabolic spectrum between healthy children. Forty-nine girls and boys aged 6-15 years were examined. MATERIAL AND METHODS: Volume of interest was located in seven brain regions: frontal lobes, basal ganglia, hippocampi, and cerebellum. RESULTS: Statistical analysis of the results showed significantly higher (p < 0.05) myo-inositol concentrations relative to the total concentrations in the boys than the girls, as well as higher absolute N-acetyl aspartate concentrations in the left frontal lobes in girls. No other significant differences were shown, except for trends in differences. CONCLUSIONS: In clinical practice the diagnostic process first of all focuses on assessing concentrations of metabolites to relative cerebellum concentration. Thus, the findings of the present study allow the conclusion that when analysing the results of 1HMRS studies in children it is not necessary to take into account the child's gender.

Brain aging: Evaluation of pH using phosphorus magnetic resonance spectroscopy.

AIM: Very important aspects of aging include age-related changes occurring in the brain. The aim of the present study was to identify the standard pH value in the entire brain volume using phosphorus magnetic resonance spectroscopy in healthy individuals of both sexes in different age groups, and then to determine whether there are differences in these values. METHODS: A total of 65 individuals aged 20-32 years (mean age 24.5 ± 2.1 years, 31 women and 34 men) and 31 individuals aged 60-81 years (mean age 64.9 ± 5.5 years, 17 women and 14 men) were studied. The phosphorus magnetic resonance spectroscopy examination was carried out using a 1.5-T magnetic resonance system. The signal was acquired from the volume of interest that covered the whole brain. RESULTS: A vast majority of the examined individuals had slightly alkaline brain pH regardless of age. In the ≥20 years group, pH was 7.09 ± 0.11, and in the ≥60 years group, the average pH was 7.03 ± 0.05. This comparison of the pH identified in all the tested individuals shows a negative correlation of pH with age. CONCLUSIONS: The present findings might provide a valuable basis for further research into "healthy aging" as well as pathology in older adults. Geriatr Gerontol Int 2018; 18: 881-885.

Brain Maturation-Differences in Biochemical Composition of Fetal and Child's Brain.

INTRODUCTION: The aim of this study was to evaluate differences in 1H MRS spectra of the brain of fetuses and children from 6 to 11 years of age. MATERIAL AND METHODS: 21 healthy fetuses in the third trimester and 22 children were examined using the proton nuclear magnetic resonance. The relative metabolite concentrations to the sum of all metabolites were calculated. RESULTS: In the 1H MRS spectra of the brain from fetuses and children, there are the same characteristic peaks: N-acetylaspartate (NAA), creatine (Cr), choline (Cho), and myo-inositol (mI). NAA/Σ, NAA/Cr, and Cr/Σ concentrations are significantly higher and Cho/Σ, Cho/Cr, mI/Σ, and mI/Cr are significantly lower in children than in the fetuses. CONCLUSIONS: It was found that the brain metabolism changes from fetal life to childhood. The results of this study may provide a valuable basis for further research on brain maturation and "healthy aging."

Regional Differences in the Concentrations of Metabolites in the Brain of Healthy Children: A Proton Magnetic Resonance Spectroscopy (1HMRS) Study.

BACKGROUND: The aim of this 1HMRS study was to identify any potential regional differences in the metabolic spectrum in the brains of healthy children. MATERIAL/METHODS: Forty-nine healthy children aged 6-15 years (mean 11.6 years) were examined, including 21 girls and 28 boys. A 1.5T MR system (xi Signa HD 1.5T General Electric) was used in patient examinations. The VOI (Volume of Interest) was defined in 7 locations: the frontal lobe in the right and left hemispheres, the basal ganglia in the right and left hemispheres, hippocampus in the right and left hemispheres and cerebellum. SAGE 7.0 software was used for the analysis of data obtained from the 1HMRS study. Differences in the concentrations of metabolites in various regions of the brain in children were verified using the t-test for independent samples. RESULTS: There were significant differences in concentration levels between various brain regions for all the examined metabolites. NAA was the metabolite characterized by the greatest regional variation with significant differences being observed between all locations. Only in the case of Lip/Cr and the ratio of the Lip concentration to the sum of the concentrations of all the metabolites no significant differences could be observed. CONCLUISONS: The results of the study show that a child's brain is inhomogeneous. The results underline the need of the regional differences in the concentrations of metabolites being taken into account when comparing the results of 1HMRS studies in children.

Differences in Metabolite Concentrations Between the Hemispheres of the Brain in Healthy Children: A Proton Magnetic Resonance Spectroscopy Study (1HMRS).

The aim of this (1)HMRS study was to identify hemispheric asymmetries in metabolismus in healthy children. The study group consisted of children of both sexes aged 6 to 15. Concentrations of 6 metabolites occurring in the brain were determined for 6 locations: hippocampus, frontal lobe, and basal ganglia in the left and right hemispheres. There were no hemispheric differences in the metabolites' concentrations in the brain in children when the variable of sex was disregarded. Only in the group of boys and in the group of girls did the findings show few discrepancies. In none of these groups, relative concentrations to creatine concentration were found to be significantly different between hemispheres. In clinical practice, concentrations of specific metabolites are most frequently determined relative to the concentration of creatine. Consequently, the analysis of standard (1)HMRS examinations in children does not need to take into account interhemispheric differences.

PH Measurements of the Brain Using Phosphorus Magnetic Resonance Spectroscopy ((31)PMRS) in Healthy Men - Comparison of Two Analysis Methods.

BACKGROUND: Intracellular pH provides information on homeostatic mechanisms in neurons and glial cells. The aim of this study was to define pH of the brain of male volunteers using phosphorus magnetic resonance spectroscopy ((31)PMRS) and to compare two methods of calculating this value. MATERIAL/METHODS: In this study, 35 healthy, young, male volunteers (mean age: 25 years) were examined by (31)PMRS in 1.5 T MR system (Signa Excite, GE). The FID CSI (Free Induction Decay Chemical Shift Imaging) sequence was used with the following parameters: TR=4000 ms, FA=90°, NEX=2. Volume of interest (VOI) was selected depending on the size of the volunteers' brain (11-14 cm(3), mean 11.53 cm(3)). Raw data were analyzed using SAGE (GE) software. RESULTS: Based on the chemical shift of peaks in the (31)PMRS spectrum, intracellular pH was calculated using two equations. In both methods the mean pH was slightly alkaline (7.07 and 7.08). Results were compared with a t-test. Significant difference (p<0.05) was found between these two methods. CONCLUSIONS: The (31)PMRS method enables non-invasive in vivo measurements of pH. The choice of the calculation method is crucial for computing this value. Comparing the results obtained by different teams can be done in a fully credible way only if the calculations were performed using the same formula.

[Presurgical functional brain examination MR (fMRI)]. / Przedoperacyjne badanie funkcjonalne mózgu MR (fMRI).

Neurosurgery in functionally relevant brain structures carries a high risk for surgery induced post-operative neurological deficits. Functional magnetic resonance imaging (fMRI) is one of the most commonly used functional neuroimaging techniques for pre-surgical brain mapping. Preoperative fMRI is optimal method to localize specific functions of the human brain that govern motor, sensory or language functions. fMRI facilitates the selection of the safest treatment and is very helpful to plane and to perform function preserving surgery in patients with brain tumors. This kind of examination is feasible for clinical routine neuroimaging and provides important diagnostic information noninvasively that is otherwise unavailable. fMRI examinations require also advanced software for data analysis.

Brain correlates of right-handedness.

Recent development of neuroimaging techniques has opened new possibilities for the study of the relation between handedness and the brain functional architecture. Here we report fMRI measurements of dominant and non-dominant hand movement representation in 12 right-handed subjects using block design. We measured possible asymmetry in the total volume of activated neural tissue in the two hemispheres during simple and complex finger movements performed either with the right hand or with the left hand. Simple movements consisted in contraction/extension of the index finger and complex movements in successive finger-thumb opposition from little finger to index finger. A general predominance of left-hemisphere activation relative to right hemisphere activation was found. Increasing the complexity of the motor activity resulted in an enlargement of the volume of consistently activated areas and greater involvement of ipsilateral areas, especially in the left hemisphere. Movements of the dominant hand elicited large contralateral activation (larger than movements of the non-dominant hand) and relatively smaller ipsilateral activation. Movements of the non-dominant hand resulted in a more balanced pattern of activation in the two hemispheres, due to relatively greater ipsilateral activation. This suggests that the dominant (right) hand is controlled mainly by the contralateral (left) hemisphere, whereas the nondominant hand is controlled by both left and right hemispheres. This effect is especially apparent during execution of complex movements. The expansion of brain areas involved in motor control in the hemisphere contralateral to the dominant hand may provide neural substrate for higher efficiency and a greater motor skill repertoire of the preferred hand.

Single voxel proton magnetic resonance spectroscopy in post-stroke depression.

Mood disorders are associated with structural, metabolic and spectroscopic changes in prefrontal regions. In the case of depression associated with stroke, there is little information about the biochemical profile of these regions, as assessed by proton magnetic resonance spectroscopy ((1)H-MRS). In a group of first-ever stroke patients, we studied the association between post-stroke depression and (1)H-MRS measurements in unaffected frontal lobes. Twenty-six patients with a first ischemic stroke located outside the frontal lobes were included in the study. Single voxel proton magnetic resonance spectroscopy ((1)H-MRS) was performed to assess N-acetylaspartate/creatine (NAA)/Cr, glutamate+glutamine (Glx)/Cr, choline (Cho)/Cr and myo-inositol (mI)/Cr ratios. Patients were assessed within the first 10 days after stroke and again four months later. The diagnosis of depression was made on the basis of clinical observation, interview and Hamilton Depression Rating Scale scores. In a group of 26 patients, eight (31%) met criteria for depression at the first assessment, and nine (35%) met criteria for depression at follow-up. Patients with depression in the immediate post-stroke phase had significantly higher Glx/Cr ratios in the contralesional hemisphere than non-depressive patients. No biochemical differences were found between the groups at 4-month follow-up. These findings suggest that post-stroke depression is accompanied by changes in frontal lobe glutamate/glutamine levels, perhaps reflecting abnormalities in glutamatergic transmission in the immediate post-stroke period.

Reduced prefrontal N-acetylaspartate in stroke patients with apathy.

BACKGROUND: Although substantial numbers of stroke patients suffer from apathy, its causes are still poorly understood. Previous studies suggest that dysfunction of the frontal lobes is implicated in the pathophysiology of motivation. Our aim was to investigate the association between proton magnetic resonance spectroscopy (H1-MRS) measurements in unaffected frontal lobes and apathy in a group of first-time stroke patients. METHODS: 31 patients with a first-time ischemic stroke located outside the frontal lobes and 20 healthy subjects were included in the study. The authors performed single voxel H1-MRS in order to measure the N-acetylaspartate/creatine (NAA)/Cr, glutamate+glutamine (Glx)/Cr, choline (Cho)/Cr and myo-inositol (mI)/Cr ratios in the frontal lobes. Patients were assessed between days 7 and 12 post stroke. Diagnosis of apathy was made on the basis of clinical observation, interview and Apathy Scale. RESULTS: 13 out of 31 patients (42%) demonstrated apathy. Patients with apathy had lower NAA/Cr ratios in the right frontal lobe than non-apathetic subjects. The patient group was divided into two subgroups: Those with left hemisphere strokes, and those with right hemisphere strokes. Of these subjects, significantly lowered NAA/Cr ratios were found in the right hemispheres of apathetic patients in the subgroup with left-sided brain lesions. CONCLUSIONS: These findings point to the association between apathy and frontal lobe integrity, suggest different reactions of the hemispheres and indicate that changes in the NAA/Cr ratio are related to the apathy.

GABA in ischemic stroke. Proton magnetic resonance study.

BACKGROUND: Experimental studies have suggested that ischemic stroke causes increment in extracellular level of gamma-aminobutyric acid in response to excessive glutamate concentration and function. The increased GABA concentration is followed by subsequent inhibition of GABA synthesis, thus leading to GABA-ergic dysfunction Enhancing GABA function seems to be a way of neuroprotec- tion after cerebral insult. Animal models have shown there is overactivity of excitatory neurotransmitters and decreased tone of GABA-ergic system also in the remote neocortical regions. Data concerning changes in brain areas outside the stroke lesion in humans are sparse. These region could be possible targets for therapeutic intervention. Progress in imaging techniques enables separation of a great number of chemical compounds .Our aim was to assess GABA levels outside the ischemic lesion by means of proton magnetic resonance spectroscopy ((1) H MRS). MATERIAL AND METHODS: The study compared 31 patients with first-ever ischemic stroke and 20 healthy subjects. Single voxel H(1) MRS was performed to measure GABA/Cr ratios in structurally normal prefrontal regions, distant from the stroke lesion. The amount of the remaining metabolites (NAA, Cho, mI, Glx) was also estimated. Patients underwent the examination in the acute phase of the disease and 3 months later. RESULTS: Both early after stroke and more than 3 months later, the patients had lower GABA levels. However, during the second examination, this difference was evident only in the frontal cortex ipsilateral to the lesion. CONCLUSIONS: These findings suggest that GABA function is decreased outside the infarct. Further studies are needed for confirmation of the results and elucidation of the possible role of GABA alterations in stroke recovery and therapy.

Central control of heart rate changes during visual affective processing as revealed by fMRI.

In the present study we addressed the question of central control of heart rate (HR) in emotions. Parallel measurement of HR changes and changes of local intensity of blood flow as indexed by fMRI in a procedure eliciting emotions allowed us to pinpoint areas of the brain responsible for HR variations during emotional arousal. In condition eliciting positive emotions we detected activation of occipito-temporal regions, anterior insula, and hypothalamus. In condition eliciting negative emotions we also detected activation of occipito-temporal regions and additionally activation of bilateral anterior insulae, right amygdala and right superior temporal gyrus. The results show that structures constituting neural network involved in HR control during emotional arousal are affect specific. Particularly the central circuit controlling HR in negative affect includes the amygdala, while central circuit controlling HR in positive affect includes the hypothalamus. Additionally activation of bilateral occipito-temporal cortex proves enhancement of visual processing of emotional material as compared to neutral material in both positive and negative affect. This might be attributed to top-down processes originating in the frontal lobe and related to shifting attention to the emotionally relevant stimuli. Activation of insular cortex is probably related to autonomic arousal accompanying watching emotional content (e.g. sweating, heart-rate changes etc.). Activation of the amygdala in the negative condition supports the well documented engagement of this structure in processing of fear and disgust.