Investigation of changes in the skin blood microcirculation when performing the hatha yoga breathing technique

Introduction. Yoga breathing exercises improve the ability to significantly reduce the respiratory rate. A decrease of the minute respiration volume results in compensatory reactions of the microcirculatory bed caused by changes in the gas composition. The reaction of the regulatory mechanisms of the microvascular bed can be evaluated by the optical non-invasive laser Doppler flowmetry method. The aim of the study was to assess the tissue microcirculation parameter changes in people performing yoga breathing exercises. Materials and methods. 25 volunteers performed yoga breathing exercises at a frequency of 3 times per minute, 2 times per minute, 1.5 times per minute, 1 time per minute for 5 minutes, and free breathing for 6 minutes before and after breathing exercises. Parameters aimed to defin the reaction of skin microcirculation in different body areas were simultaneously recorded in six sites by laser Doppler flowmetry using a distributed system of wearable analyzers. The parameters of tissue microcirculation recorded by the method of laser Doppler flowmetry were: the index of microcirculation (Im), nutritive blood flow (Imn), the amplitude of myogenic (Am), neurogenic (An), endothelial (Ae), respiratory (Ar) and cardiac (Ac) regulation circuits. Results. Yoga breathing exercises led to increase of microcirculation index at all breathing frequencies. Breathing at a frequency of 1.5 and 1/minute leads to a significant increase in nutritional blood flow. Low-frequency breathing exercises lead to an increase in blood pressure at the lowest breathing rates – 1.5/minute and 1/minute. The most significant changes were achieved at the lowest respiration rates (1 and 1.5/minute), that could be associated with hypoxic-hypercapnic mechanisms. Conclusion. The absence of significant changes in microcirculation parameters after low-frequency respiration during measurements in the supraorbital arteries in both groups characterizes the work of homeostatic mechanisms for maintaining brain perfusion in stressful situations for the body (low-frequency types of respiration, hypercapnia and hypoxia). When measured in the extremities, a change in the effect of the circulatory system regulatory mechanisms was observed; along with an increase in skin perfusion and the nutritional component, it can characterize the compensatory reaction of the microcirculation to respiration change.

Differential Brain Perfusion Changes Following Two Mind–Body Interventions for Fibromyalgia Patients: an Arterial Spin Labelling fMRI Study

Objectives Further mechanistic insight on mind–body techniques for fibromyalgia (FMS) is needed. Arterial spin labelling (ASL) imaging can capture changes in regional cerebral blood flow (rCBF) that relate to spontaneous pain. Methods We recruited FMS patients undergoing either mindfulness-based stress reduction training (MBSR, n = 14) or a psychoeducational programme (FibroQoL, n = 18), and a control FMS group with no add-on treatment (n = 14). We acquired whole-brain rCBF maps and self-report measures at baseline and following treatment and explored interaction effects in brain perfusion between the treatment group and session with a focus on the amygdala, the insula and the anterior cingulate cortex (ACC). Results We identified a significant interaction effect in the amygdala, which corresponded with rCBF decreases following FibroQoL specifically. At baseline, rCBF in the amygdala for the FibroQoL group correlated with pain catastrophizing and anxiety scores, but not after treatment, suggesting a decoupling between activity in the amygdala and negative emotional symptoms of FMS as a consequence of treatment. Baseline rCBF correlated positively with pain symptoms in the ACC and the anterior insula across all patients; moreover, the correlation between rCBF changes post intervention in the insula and pain improvement was negative for both treatments and significantly different from the control group. We suggest that there is disruption of the typical relationship between clinical pain and activity as a product of these two nonpharmacological therapies. Conclusions We have demonstrated that different mind-to-body treatments correspond to differential changes in clinical symptoms and brain activity patterns, which encourages future research investigating predictors of treatment response. Trial Registration NCT02561416.

Brain perfusion and hemodynamic changes in moyamoya desease

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Correlation of Neuropsychiatric Symptoms in Dementia with Brain Perfusion: A 99mTc-SPECT-HMPAO Study with Brodmann Areas Analysis

Background: Neuropsychiatric symptoms (NPSs) are common in dementia. Their evaluation is based on Neuropsychiatric Inventory (NPI). Neuroimaging studies have tried to elucidate the underlying neural circuits either in isolated NPSs or in specific forms of dementia. Objective: : The objective of this study is to evaluate the correlation of NPS in the NPI with Brodmann areas (BAs) perfusion, for revealing BAs involved in the pathogenesis of NPSs in dementia of various etiologies. Method: We studied 201 patients (82 with Alzheimer's disease, 75 with Frontotemporal dementia, 27 with Corticobasal Syndrome, 17 with Parkinson Disease/Lewy Body Dementia). Exploratory factor analysis was carried out to evaluate underlying groups of BAs, and Principal Component analysis was chosen as extraction method using Varimax rotation. Partial correlation coefficients were computed to explore the association of factors obtained from analysis and NPI items controlling for age, educational yeas, and ACE-R. Results: We found 6 BAs Factors(F); F1 (BAs 8,9,10,11,24,32,44,45,46,47, bilaterally), F2 (Bas 4,5,6,7,23,31, bilaterally), F3 (BAs 19,21,22,37,39,40, bilaterally), F4 (BAs 20,28,36,38, bilaterally), F5 (BAs 25, bilaterally) and F6 (BAs 17,18, bilaterally). Significant and negative correlation was found between NPI1 (delusions) and F3,F6, NPI2 (hallucinations) and F6, NPI7 (apathy) and F1,F4,F5, NPI3 (agitation) - NPI10 (aberrant motor behavior) - NPI12 (eating disorders) and F1. We did not find any significant correlation for NPI4,5,6,8,9,11 (depression, anxiety, euphoria, disinhibition, irritability, sleep disorders, respectively). Conclusion: Several NPSs share the same BAs among different types of dementia, while the manifestation of the rest may be attributed to different neural networks. These findings may have an impact on patients’ treatment.

Transverse Sinus Stenosis in Venous Pulsatile Tinnitus Patients May Lead to Brain Perfusion and White Matter Changes

Objective: Transverse sinus stenosis (TSS) is associated with various symptoms, but whether it can lead to pathological brain changes is unclear. This study aimed to investigate brain changes in venous pulsatile tinnitus (PT) patients with TSS.Materials and Methods: In this study, fifty-five consecutive venous PT patients and fifty age- and gender-matched healthy controls (HCs) were investigated. In CT venography, the combined conduit score (CCS) was used to assess the degree of TSS in venous PT patients. Magnetic resonance venography was used to assess TSS in HCs. All the participants had undergone arterial spin labeling and structural MRI scans.Results: Two patients without TSS and ten HCs with TSS were excluded. Fifty-three venous PT patients with TSS and 40 HCs without TSS were included in this study. All the patients had unilateral cases: 16 on the left and 37 on the right. Based on the CCS, the patients were divided into high-degree TSS (a score of 1–2) (n = 30) and low-degree TSS groups (a score of 3–4) (n = 23). In the whole brain and gray matter, the patients with high-degree TSS showed decreased cerebral blood flow (CBF) compared with patients with low-degree TSS as well as HCs (P < 0.05), and no significant difference in CBF was found in patients with low-degree TSS and HCs (P > 0.05). In white matter (WM) regions, the patients with high-degree TSS exhibited decreased CBF relative to the HCs (P < 0.05). The incidence of cloud-like WM hyperintensity was significantly higher in the above two patient groups than in the HC group (P < 0.05).Conclusion: TSS in venous PT patients may lead to decreased CBF and cloud-like WM hyperintensity. These neuroimaging findings may provide new insights into pathological TSS in venous PT.

SPECT Functional Neuroimaging Distinguishes Adult Attention Deficit Hyperactivity Disorder From Healthy Controls in Big Data Imaging Cohorts

Background: The diagnosis of attention deficit hyperactivity disorder (ADHD) relies on history and observation, as no reliable biomarkers have been identified. In this study, we compared a large single diagnosis group of patients with ADHD (combined, inattentive, and hyperactive) to healthy controls using brain perfusion single-photon emission computed tomography (SPECT) imaging to determine specific brain regions which could serve as potential biomarkers to reliably distinguish ADHD.Methods: In a retrospective analysis, subjects (n = 1,135) were obtained from a large multisite psychiatric database, where resting state (baseline) and on-task SPECT scans were obtained. Only baseline scans were analyzed in the present study. Subjects were separated into two groups – Group 1 (n = 1,006) was composed of patients who only met criteria for ADHD with no comorbid diagnoses, while a control group (n = 129) composed of individuals who did not meet criteria for any psychiatric diagnosis, brain injury, or substance use served as a non-matched control. SPECT regions of interests (ROIs) and visual readings were analyzed using binary logistic regression. Predicted probabilities from this analysis were inputted into a Receiver Operating Characteristic analysis to identify sensitivity, specificity, and accuracy.Results: The baseline ROIs and visual readings show significant separations from healthy controls. Sensitivity of the visual reads was 100% while specificity was >97%. The sensitivity and specificity of the post-hoc ROI analysis were both 100%. Decreased perfusion was primarily seen in the orbitofrontal cortices, anterior cingulate gyri, areas of the prefrontal cortices, basal ganglia, and temporal lobes. In addition, ROI analysis revealed some unexpected areas with predictive value in distinguishing ADHD, such as cerebellar subregions and portions of the temporal lobes.Conclusions: Brain perfusion SPECT distinguishes adult ADHD patients without comorbidities from healthy controls. Areas which were highly significantly different from control and thus may serve as biomarkers in baseline SPECT scans included: medial anterior prefrontal cortex, left anterior temporal lobe, and right insular cortex. Future studies of these potential biomarkers in ADHD patients with comorbidities are warranted.

Long-term cognitive changes after revascularization surgery in adult patients with ischemic moyamoya disease

Introduction: Revascularization surgery for adult moyamoya disease (MMD) with ischemic presentation changes cognitive function and prevents further cerebral ischemic events. Most studies, however, repeated neuropsychological evaluation within 1 year after surgery. Our previous prospective cohort study of adult patients with MMD with misery perfusion who underwent direct revascularization surgery showed cognitive improvement and decline in 31% and 44%, respectively, of the patients 2 months after surgery. The present prospective study aimed to elucidate the 5-year cognitive changes after direct revascularization surgery in adult patients with cerebral misery perfusion due to ischemic MMD by following the same patients. Methods: In total, 31 patients were prospectively followed up for 5 years after direct revascularization surgery. Five types of neuropsychological tests were performed preoperatively, 2 months after surgery, and at the end of the 5-year follow-up. Cerebral blood flow in the symptomatic cerebral hemisphere relative to that in the ipsilateral cerebellar hemisphere (hemispheric RCBF) was measured using brain perfusion single-photon emission computed tomography preoperatively and at the end of the 5-year follow-up. Results: Based on results of pre- and postoperative neuropsychological tests, 11, 10, and 10 patients showed cognitive improvement, no change in cognitive function, and cognitive decline, respectively, at the end of the 5-year follow-up. These ratios were not significantly different compared with those 2 months after surgery (cognitive improvement, no change in cognitive function, and cognitive decline in 10, eight, and 13 patients, respectively). Although hemispheric RCBF was significantly greater at the end of the 5-year follow-up than before surgery in patients with cognitive improvement (80.7 ± 6.1% versus 92.9 ± 5.5%; p = 0.0033) and in those showing no change in cognitive function (85.6 ± 3.5 versus 91.5 ± 5.2%; p = 0.0093), this value was significantly lower at the end of the 5-year follow-up than before surgery in patients with cognitive decline (83.8 ± 3.7 versus 81.0 ± 5.8%; p = 0.0367). Conclusion: One-third of adult patients with cerebral misery perfusion due to ischemic MMD who underwent direct revascularization surgery exhibited cognitive improvement, and one-third exhibited decline at the end of the 5-year follow-up. The former and latter patients had increased and decreased CBF, respectively, in the affected cerebral hemisphere at the end of the 5-year follow-up compared with preoperative brain perfusion.

Rapid and Persistent Decrease in Brain Tissue Oxygenation in Ovine Gram-negative Sepsis

The changes in brain perfusion and oxygenation in critical illness, which are thought to contribute to brain dysfunction, are unclear due to the lack of methods to measure these variables. We have developed a technique to chronically measure cerebral tissue perfusion and oxygen tension in unanesthetised sheep. Using this technique, we have determined the changes in cerebral perfusion and PO2 during the development of ovine sepsis. In adult Merino ewes, fibre-optic probes were implanted in the brain, renal cortex and renal medulla to measure tissue perfusion, oxygen tension (PO2) and temperature and flow probes were implanted on the pulmonary and renal arteries. Conscious sheep were infused with live Escherichia coli for 24-hr, which induced hyperdynamic sepsis; mean arterial pressure decreased (85.2±5.6 to 71.5±8.7 mmHg), while cardiac output (4.12±0.70 to 6.15±1.26 L/min) and total peripheral conductance (48.9±8.5 to 86.8±11.5 mL/min/mmHg) increased (n=8, all P<0.001) and arterial PO2 decreased (104±8 to 83±10 mmHg; P<0.01). Cerebral perfusion tended to decrease acutely, although this did not reach significance, but there was a significant and sustained decrease in cerebral tissue PO2 (32.2±10.1 to 18.8±11.7 mmHg) after 3 h and to 22.8±5.2 mmHg after 24-hr of sepsis (P<0.02). Sepsis induced large reductions in both renal medullary perfusion and PO2 but had no effect in the renal cortex. In ovine sepsis, there is an early decrease in cerebral PO2 that is maintained for 24-hours despite minimal changes in cerebral perfusion. Cerebral hypoxia may be one of the factors causing sepsis-induced malaise and lethargy.