Significant Differences In rCBF Research Articles

Role of perfusion weighted imaging in the differential diagnosis of intracranial space occupying lesions

Introduction. Magnetic Resonance Imaging (MRI) is a well-established modality for identifying intracranial space-occupying lesions (ICSOLs). However, conventional MRI has limitations in the cerebral glioma accurate grading. Advanced techniques, like Diffusion-Weighted Imaging (DWI), Perfusion MRI, and Magnetic Resonance Spectroscopic Imaging (MRS), have been introduced to address these limitations. Aims and objective. The primary objective of this research is to assess the significance of perfusion-weighted imaging (PWI) in distinguishing intracranial space-occupying lesions (ICSOLs), with a specific emphasis on its capacity to refine diagnostic accuracy and advance the classification of cerebral gliomas. Materials and methods. A prospective observational research involving 38 patients having ICSOLs used a Philips Multiva 1.5 Tesla MRI system. The protocol included DWI, ADC (Apparent Diffusion Coefficient) analysis, and perfusion imaging. Results. The study population (n=38) had a diverse age range (22-70 years), with a majority in the 30-40 age group. High-grade gliomas constituted 43.2% of all the cases. Significant differences in rCBF, rCBV, and MTT have been observed among HGGs & LGGs. Specific cut-off values were used to predict glioma grades. Discussion. Comparisons with existing studies validated these findings, emphasizing the utility of advanced physiological techniques in enhancing diagnostic precision. Discrepancies with certain studies have highlighted the need for a comprehensive approach to lesion characterization. Conclusion. Intracranial lesion diagnosis, especially for meningiomas, demonstrated comparable efficacy between conventional and advanced techniques. While conventional MRI can differentiate lower-grade from higher-grade gliomas to a limited extent, the combination of advanced physiological approaches significantly improves specificity in tumor categorization.

Impact of atrial fibrillation on the cognitive decline in Alzheimer’s disease

BackgroundAtrial fibrillation (AF) is a strong risk factor for Alzheimer’s disease (AD) independent of ischemic stroke. However, the clinicopathological impact of AF on the severity of AD has not been well elucidated. We aimed to investigate the clinical differences between dementia patients with AF and those without AF by means of imaging data.MethodsFollowing approval from the institutional ethics committee, patients with newly diagnosed AD or amnestic mild cognitive impairment (aMCI) were retrospectively screened (n = 170, 79.5 ± 7.4 years old). Cognitive function was assessed using the Mini-Mental State Examination (MMSE). Based on the MRI data, the cerebral volume, cerebral microbleeds (CMBs), periventricular white matter lesions (WMLs), and deep WMLs were evaluated. The regional cerebral blood flow (rCBF) was measured using 123I-IMP SPECT.ResultsOf the patients, 14 (8.2%) and 156 (91.8%) had AF (AF group) and sinus rhythm (SR group), respectively. The AF group had significantly lower MMSE scores than the SR group (average [standard deviation (SD)]: 19.4 [4.4] and 22.0 [4.4], respectively; p = 0.0347). Cerebral volume and CMBs did not differ between the two groups. The periventricular WMLs, but not the deep WMLs, were significantly larger in the AF group than in the SR group (mean [SD] mL: 6.85 [3.78] and 4.37 [3.21], respectively; p = 0.0070). However, there was no significant difference in rCBF in the areas related to AD pathology between the two groups.ConclusionAD and aMCI patients with AF showed worse cognitive decline along with larger periventricular WMLs compared to those with SR, although the reduction of rCBF was not different between patients with AF and SR. The white matter lesions may be a more important pathology than the impairment of cerebral blood flow in dementia patients with AF. A larger study is needed to confirm our findings in the future.

A-176 Regional Cerebral Blood Flow in Self-Reported Post-Traumatic Stress Disorder in Adults

Abstract Objective: The aim of this study is to identify regional cerebral blood flow (rCBF) differences between adults who self-reported high symptoms of Post-Traumatic Stress Disorder. Method: Subjects were selected from a de-identified database for adult SPECT scans. Scores were standardized to T-scores for each database. Twenty percent of the sample from each database were selected on the basis of self-reported levels of PTSD symptoms using the Amen Adult General Symptom Checklist (Amen, 1997). The final sample consisted of 350 Adults [Mage=36.70, majority-white (65.4%) and female (56.9%)]. Significant differences existed between groups for age. A MANOVA was utilized to test the difference in concentration rCBF between adults controlling for age. Results: Groups were compared across 17 variables representing different areas of the brain. Significant differences (p<.05) in rCBF were found in high levels of self-reported PTSD. Specifically, significant differences were noted in the left and right limbic areas with adults reporting high levels of PTSD having increased rCBF in these regions. Differences were also significant in the left and right basal ganglia regions with those reporting higher levels of PTSD having increased rCBF. Conclusion: Results indicate that there are significant differences in rCBF between adults with high self-reported levels of symptoms of PTSD. This suggests that adults with PTSD experience increased rCBF in the limbic and basal ganglia which both play a role in memory, emotions, and anxiety. Clinicians can use this information in the future to identify individuals that are at a high-risk for developing PTSD.

A-175 Regional Cerebral Blood Flow in Self-Reported Anxiety in Adults versus Children

Abstract Objective: The aim of this study is to identify regional cerebral blood flow (rCBF) differences between children and adults with high levels of self-reported anxiety. Method: Subjects were selected from two independent clinical outpatient databases for child and adult SPECT scans. Scores were standardized to T scores for each database. The highest 20% of self-reported anxiety was selected from each database. The final sample consisted of 3226 Adults [Mage=37.78, majority-white (68.7%) and male (54.7%)] and 545 children [Mage=13.58, majority-white (48.6%) and male (59.3%)] Significant differences existed between groups for gender and race. An ANCOVA was utilized to test the difference in concentration rCBF between adults and children controlling for these t covariates. Results: Groups were compared across 17 variables representing different areas of the brain (p<.05). Children had significantly higher rCBF than adults in the limbic [left: F(1,3767)=15.893, p<.001 and right: F(1,3767)=48.699, p<.001], basal ganglia [left: F(1,3767)=30.138, p<.001 and right: F(1,3767)=61.191, p<.001], frontal [left: F(1,3767)=142.244, p<.001 and right: F(1,3767)=112.273, p<.001], motor sensory right F(1,3767)=679.063, p=.008, and vermis F(1,3767)=50.025, p<.001 regions. Adults had significantly higher rCBF than children in the parietal regions [left: F(1,3767)=42.235, p<.001 and right: F(1,3767)=82.708, p<.001]. Discussion: There are significant differences in rCBF between children and adults with high self-reported levels of anxiety. This indicates that different neuronal mechanisms in adults and children are involved when experiencing high levels of anxiety. These findings can help clinicians better understand differences in how anxiety is expressed neurologically between children and adults.

EVALUATION OF INTRACRANIAL SPACE OCCUPYING LESIONS BY CT PERFUSION STUDY

Introduction: CT perfusion plays an invaluable role here as it detects microscopic differences in the internal vascularity of lesions and aids in their characterisation and significantly raises the diagnostic accuracy. In this Retrospective study, we performed CT Perfusion in various intracranial focal lesions and studied their perfusion characters and tried to evaluate & differentiate between them.
 Methods: This Retrospective Analytical study involved data of 100 of the randomly selected patients ( candidates / study subjects .CTP was performed with dual?slice dynamic multi?detector CT scanner in 100 patients prior to surgery or stereotactic biopsy with age ranging from 15 to 70 years. Patients below 15 years, pregnant women, and very old patients with compromised renal functions were not included in this study. It was noted that Informed consent was taken from all patients .
 Results: Perfusion parameters like rCBF and rCBV were calculated with ROI including the whole of the lesion and 1?2 cm in the periphery of the lesion. The rCBF and rCBV of neoplastic lesions with statistically significant difference in rCBF and rCBV of low?grade gliomas from high?grade gliomas, lymphomas, and metastases.There was statistically significant difference in rCBF (P < 0.002) and rCBV (P < 0.001) of TWT, TOT, and abscesses.
 Keyword: ICSOL , CT Perfusion , Cerebral blood flow , Cerebral blood volume.

A-67 Measuring Regional Cerebral Blood Flow with Single-Photon Emission Computed Tomography (SPECT) in Obsessive–Compulsive Disorder

Abstract Objective To identify regional cerebral blood flow (rCBF) differences between individuals with Obsessive–Compulsive Disorder (OCD) and healthy controls. Mehtods: Healthy controls (n = 81, Mage = 41.9, 53.0% female, 42.0% Caucasian) and persons diagnosed by psychiatric examination with OCD (n = 1020, Mage = 34.8, 33.6% female, 66.3% Caucasian) were selected from a deidentified adult clinical outpatient database. Those with comorbid diagnoses were included. Significant differences (alpha = 0.001) were found for age [t(1099) = −4.4], gender [χ2(2) = 25.7], and race [χ2(12) = 30.1] between groups and therefore were controlled for. Significant rCBF differences were noted in the cerebellum [left:F(1,1096) = 21.6; right:F(1,1096) = 18.3], limbic system [left:F(1,1096) = 12.2; right:F(1,1096) = 10.4], and basal ganglia [left:F(1,1096) = 18.6; right:F(1,1096) = 18.3]. Results Group means comparisons indicated higher perfusion in the cerebellum for the OCD group. Lower perfusion was found in the limbic system and basal ganglia in the OCD group. This study found higher perfusion in the cerebellum among the OCD group. Previous research found increased rCBF in the left cerebellum in OCD before pharmacotherapy. In the right cerebellum, increased rCBF was found among participants with early-onset OCD. Conclusion Overall, there is limited research on the cerebellum because of its use as a reference point. No research was found regarding the limbic system in OCD using SPECT; however, other neuroimaging found increased amygdala reactivity to emotional face stimuli. This study found lower perfusion in the basal ganglia among the OCD group. Previous research found hypoperfusion in the right; however, hypoperfusion in the left was not significant. Updated OCD and rCBF research with SPECT are needed. Limitations included the inclusion of comorbidities and use of DSM-IV-TR rather than DSM-5 diagnosis criteria.

Functional Brain Imaging During Rest and Pain: Differences According to Race and Knee Osteoarthritis

Considerable evidence suggests that knee osteoarthritis (OA)-related clinical pain and disability significantly differs according to racial background. However, brain mechanisms underlying these differences are not well understood. We investigated altered central pain processing in a sample comprised of Non-Hispanic Black (NHB) and Non-Hispanic White (NHW) adults with and without knee OA. NHB and NHW participants with knee OA (n = 123) and without knee OA (N = 41) were recruited to complete a brain imaging protocol using Arterial Spin Labeling (ASL) on a 3T fMRI scanner. Participant's regional cerebral blood flow (rCBF), a measure of brain activation, was examined at rest and during pressure pain stimulation. Aim 1 was to examine altered central processing in people with knee OA compared to people without knee OA. Aim 2 assessed racial group differences in central processing among NHB and NHW adults with knee OA. People with knee OA showed significant differences in rCBF at rest and during pain in the anterior cingulate cortex, sensory-motor cortex, para-hippocampal gyrus, and amygdala in comparison to people without knee OA. For people with knee OA, ethnic differences between NHWs (n = 52) and NHBs (n = 71) were present in the cingulate gyrus, amygdala, thalamus, sensory-motor cortex, and cerebellum. Comparing people with knee OA to people without knee OA at rest while controlling for race, we found a significant effect in the thalamus (p = .036) and amygdala (p = .046). For people with knee OA, NHBs vs NHWs showed a significant effect for the difference score (pain - rest) in the cerebellum (p = .012) when controlling for age and education. These results indicate that knee OA and racial background may be important contributors to altered central nervous system processing of pain. Supported in part by NIH/NIA grant AG033906 and the NIH/NCATS Clinical and Translational Science Awards to the University of Florida (UL1 T64) and the University of Alabama at Birmingham (ULITR000165).

Diets Varying in Carbohydrate Content Differentially Alter Brain Activity in Homeostatic and Reward Regions in Adults.

Obesity has one of the highest refractory rates of all chronic diseases, in part because weight loss induced by calorie restriction, the first-line treatment for obesity, elicits biological adaptations that promote weight regain. Although acute feeding trials suggest a role for macronutrient composition in modifying brain activity related to hunger and satiety, relevance of these findings to weight-loss maintenance has not been studied. We investigated effects of weight-loss maintenance diets varying in macronutrient content on regional cerebral blood flow (rCBF) in brain regions involved in hunger and reward. In conjunction with a randomized controlled feeding trial, we investigated the effects of weight-loss maintenance diets varying in carbohydrate content [high, 60% of total energy: n=20; 6 men/14 women; mean age: 32.5 y; mean BMI (in kg/m 2): 27.4; moderate, 40% of total energy: n=22; 10 men/12 women; mean age: 32.5 y; mean BMI: 29.0; low, 20% of total energy: n=28; 12 men/16 women; mean age: 33.2 y; mean BMI: 27.7] on rCBF in brain regions involved in hunger and reward preprandial and 4 h postprandial after 14-20 wk on the diets. The primary outcome was rCBF in the nucleus accumbens (NAcc) at 4 h postprandial; the secondary outcome was preprandial rCBF in the hypothalamus. Consistent with a priori hypothesis, at 4 h postprandial, NAcc rCBF was 43% higher in adults assigned to the high- compared with low-carbohydrate diet {P[family-wise error (FWE)-corrected]<0.05}. Preprandial hypothalamus rCBF was 41% higher on high-carbohydrate diet [P(FWE-corrected)<0.001]. Exploratory analyses revealed that elevated rCBF on high-carbohydrate diet was not specific to prandial state: preprandial NAcc rCBF [P(FWE-corrected)<0.001] and 4 h postprandial rCBF in hypothalamus [P(FWE-corrected)<0.001]. Insulin secretion predicted differential postprandial activation of the NAcc by diet. We report significant differences in rCBF in adults assigned to diets varying in carbohydrate content for several months, which appear to be partially associated with insulin secretion. These findings suggest that chronic intake of a high-carbohydrate diet may affect brain reward and homeostatic activity in ways that could impede weight-loss maintenance. This trial was registered at clinicaltrials.gov as NCT02300857.

Combined structural and diffusion tensor imaging detection of ischemic injury in moyamoya disease: relation to disease advancement and cerebral hypoperfusion.

The microstructural integrity of gray and white matter is decreased in adult moyamoya disease, suggesting covert ischemic injury as a mechanism of cognitive dysfunction. Establishing a microstructural brain imaging marker is critical for monitoring cognitive outcomes following surgical interventions. The authors of the present study determined the pathophysiological basis of altered microstructural brain injury in relation to advanced arterial occlusion, cerebral hypoperfusion, and cognitive function. The authors examined 58 patients without apparent brain lesions and 30 healthy controls by using structural MRI, as well as diffusion tensor imaging (DTI). Arterial occlusion in each hemisphere was classified as early or advanced stage based on MRA and posterior cerebral artery (PCA) involvement. Regional cerebral blood flow (rCBF) was measured with N-isopropyl-p-[123I]-iodoamphetamine SPECT. Furthermore, cognitive performance was examined using the Wechsler Adult Intelligence Scale, Third Edition and the Trail Making Test (TMT). Both voxel- and region of interest-based analyses were performed for groupwise comparisons, as well as correlation analysis, using parameters such as cognitive test scores; gray matter volume; fractional anisotropy (FA) of association fiber tracts, including the inferior frontooccipital fasciculus (IFOF) and superior longitudinal fasciculus (SLF); PCA involvement; and rCBF. Compared to the early stages, advanced stages of arterial occlusion in the left hemisphere were associated with a lower Performance IQ (p = 0.031), decreased anterior cingulate volumes (p = 0.0001, uncorrected), and lower FA in the IFOF, cingulum, and forceps major (all p < 0.01, all uncorrected). There was no significant difference in rCBF between the early and the advanced stage. In patients with an advanced stage, PCA involvement was correlated with a significantly lower Full Scale IQ (p = 0.036), cingulate volume (p < 0.01, uncorrected), and FA of the left SLF (p = 0.0002, uncorrected) compared to those with an intact PCA. The rCBF was positively correlated with FA of the SLF, IFOF, and forceps major (r > 0.34, p < 0.05). Global gray matter volumes were moderately correlated with TMT part A (r = 0.40, p = 0.003). FA values in the left SLF were moderately associated with processing speed (r = 0.40, p = 0.002). Although hemodynamic compensation may mask cerebral ischemia in advanced stages of adult moyamoya disease, the disease progression is detrimental to gray and white matter microstructure as well as cognition. In particular, additional PCA involvement in advanced disease stages may impair key neural substrates such as the cingulum and SLF. Thus, combined structural MRI and DTI are potentially useful for tracking the neural integrity of key neural substrates associated with cognitive function and detecting subtle anatomical changes associated with persistent ischemia, as well as disease progression.

Cerebral hemodynamics associated with fluid-attenuated inversion recovery hyperintense vessels in patients with extracranial carotid artery stenosis.

Fluid-attenuated inversion recovery hyperintense vessels (FHVs) are linked to sluggish or disordered blood flow. The purpose of this study is to compare FHVs with digital subtraction angiography (DSA) findings and cerebral hemodynamic changes on acetazolamide challenge SPECT and to determine the clinical and imaging metrics associated with FHVs in patients with extracranial carotid artery stenosis (ECAS). The subjects were patients with chronic ECAS who underwent carotid artery stenting in our department between March 2011 and October 2018. Relationships of FHVs with age, sex, medical history, cerebral angiographic findings using DSA, and quantitative values of cerebral blood flow (CBF) were examined. The resting CBF (rCBF) and cerebrovascular reactivity (CVR) in the middle cerebral artery territory were measured quantitatively using SPECT with acetazolamide challenge. We used multivariate logistic regression analysis to identify independent predictors of FHVs. Of 173 patients included, 92 (53.2%) had FHVs. Patients with FHVs had more severe stenosis (P < 0.01) and more leptomeningeal collateral vessels (P < 0.01). FHV-positive cases had significantly reduced CVR compared with FHV-negative cases (P < 0.01), although there was no significant difference in rCBF between FHV-positive and FHV-negative cases. Logistic regression analysis showed that ipsilateral rCBF and ipsilateral CVR were significant predictors for FHVs (P < 0.01). In patients with ECAS, cerebral hemodynamic metrics, especially ipsilateral rCBF and ipsilateral CVR, are associated with the presence of FHVs.

Abstract WP59: Cerebral Blood Flow Increase After Endovascular Thrombectomy on Perfusion Weighted Image is Associated With Hemorrhagic Transformation

Introduction: The role of increased CBF after endovascular thrombectomy in post-ischemic hyperperfusion has not been studied in detail. We aimed to investigate the timing of CBF increases on PWI after thrombectomy in association with hemorrhagic transformation. Methods: We analyzed prospectively collected data in consecutive patients treated with endovascular thrombectomy. Inclusion criteria were: (1) patients with ICA or M1 occlusion, and (2) PWI and GRE obtained within 12 hours and 12-48 hours after thrombectomy. We compared each rCBF with early hemorrhage (within 12 hours after thrombectomy), late hemorrhage (12-48 hour) and non-hemorrhage in basal ganglia (BG) and MCA cortical or subcortical (CS) region. In each PWI dataset, ROIs were placed in two slice levels of the BG and three slice levels of the CS region. Results: Fifty-three patients met inclusion criteria. Early BG hemorrhages were noted in 13 patients, with 4 late BG hemorrhage, 8 early CS hemorrhage and 3 late CS hemorrhage. There were no significant differences on rCBF in PWI within 12 hours after thrombectomy between early hemorrhage, late hemorrhage and non-hemorrhage groups. In contrast, rCBF on 12-48 hours PWI in the BG region was significantly higher in the early BG hemorrhage than non-BG hemorrhage (lower BG slice 1.36 vs 1.01, p&lt;0.001, upper BG slice 1.33 vs 0.96, p&lt;0.001) and rCBF in CS region were significantly higher in early CS hemorrhage than non-CS hemorrhage (lower CS slice 1.55 vs 0.98, p=0.001, middle CS slice 1.31 vs 0.92, p=0.018). There were no significant differences in rCBF on 12-48 hours PWI between the late hemorrhage and non-hemorrhage group. Conclusions: Most intracerebral hemorrhages after thrombectomy were seen within 12 hours after intervention. A rCBF increase in hemorrhage cases was not seen on PWI within 12 hours after thrombectomy. rCBF increases on PWI 12-48 hours after thrombectomy, however, was associated with post-thrombectomy hemorrhage within 12 hours.

Efficacy of nicergoline treatment in Parkinson’s disease associated with dementia

Parkinson’s disease (PD) has a variable spectrum of cognitive impairment. However, there are no clear evident-based management guidelines for PD with dementia (PDD). Alternative treatments for PDD are therefore required. We conducted this longitudinal study to evaluate the efficacy of nicergoline in treating PDD by analyzing changes in regional cerebral blood flow (rCBF) and neuropsychological tests before and after nicergoline administration. A total of nine PDD patients who received nicergoline therapy (PDD + N) and 14 PD patients who did not receive nicergoline therapy (PDD − N) underwent single photon emission computed tomography (SPECT) and clinical assessments at baseline and 12-month follow-up visits. The PDD + N received nicergoline at 30 mg twice per day. Changes in rCBF were compared between the groups, and correlation analysis was performed to determine possible relationship between rCBF and clinical characteristics. There were no significant differences in rCBF between the two groups at baseline. Although changes in cognitive test scores and the motor severity scale were not significantly different between baseline and the 12-month follow-up within groups, rCBF was lower in both the temporal and inferior frontal restricted areas in the PDD − N group than the PDD + N at the 12-month follow-up visit. In conclusions, nicergoline appears to delay the speed of deterioration of cognitive function in patients with PDD based on our observation of decreased rCBF in the temporal regions and inferior frontal regions of PDD − N patients compared to PDD + N patients after 12-month of nicergoline therapy. Therefore, we cautiously suggest that nicergoline administration in PDD patients may slow progression of cognitive impairment in affected brain regions.

Effects of nicergoline treatment on regional cerebral blood flow in early Alzheimer's disease

AbstractAlzheimer's disease (AD) is associated with reduction of regional cerebral blood flow (rCBF) in various brain regions. Although nicergoline has been used to treat cognitive impairment in various types of dementia, the effect of nicergoline on brain perfusion in AD has not been elucidated. The aim of the study was to examine the effect of nicergoline on rCBF in patients with early AD using technetium‐99m hexamethylpropylene amine oxime single‐photon emission computed tomography (SPECT). For 1.7 years on average, 22 patients with early AD received nicergoline (30 mg twice daily) and acetylcholinesterase inhibitors (AChEI), whereas other 22 patients received AChEI only. All patients underwent assessment of dementia severity and SPECT scans at baseline and follow‐up. We compared baseline rCBF and annual percent change of rCBF between the two groups. There were no significant differences in rCBF between the groups at baseline. Although changes in dementia severity was not statistically different, the annual percent changes of rCBF were higher in the left temporal pole (−0.12 ± 3.95 vs −3.38 ± 3.30, P = 0.002) and middle cingulate gyrus (1.91 ± 3.58 vs −1.34 ± 3.17, P = 0.002) among the nicergoline group. Our study demonstrated that nicergoline treatment combined with AChEI either better preserves or further improves cerebral perfusion in the temporal and cingulate cortices in patients with early AD compared to AChEI treatment alone. These results may indicate potential beneficial effects of nicergoline on brain functions in AD.

Cerebral blood flow and Alzheimer's disease-related biomarkers in cerebrospinal fluid in idiopathic normal pressure hydrocephalus.

Alzheimer's disease (AD) pathology is highly prevalent in patients with idiopathic normal pressure hydrocephalus (iNPH), and the presence of AD pathology may involve regional cerebral blood flow (rCBF). In this study, we examined the relationship between rCBF and AD-related biomarkers in the cerebrospinal fluid of iNPH patients. Patients with iNPH (n = 39) were classified into groups with (iNPH/AD+) (n=15) and without (iNPH/AD-) (n=24) high biomarker probability of AD (i.e. combined low amyloid β 42 and high total tau in the cerebrospinal fluid). rCBF was quantified in 17 regions of interest by N-isopropyl-p-[123 I]iodoamphetamine single-photon emission computed tomography with the autoradiography method. We compared rCBF between the iNPH/AD- and iNPH/AD+ groups at baseline using a t-test and then compared changes in rCBF after shunt surgery between the groups using a paired t-test and two-way repeated measures ANOVA. At baseline, there were no significant differences in rCBF between the groups in most regions apart from the putamen. After shunt surgery, a significant increase in rCBF in the putamen, amygdala, hippocampus, and parahippocampal gyrus was observed in iNPH/AD- patients. In iNPH/AD+ patients, no significant improvement in rCBF was observed in any region. In repeated measures analysis of variance, a significant group × shunt interaction was observed in the parietal lobe, frontal lobe, posterior cingulate cortex, precuneus, lateral temporal lobe, amygdala, hippocampus, parahippocampal gyrus, and putamen. Improvement in rCBF after shunt surgery in iNPH/AD+ patients may be poorer than that in iNPH AD- patients.

Chronic intracranial artery stenosis: Comparison of whole-brain arterial spin labeling with CT perfusion

PurposeTo evaluate the potential clinical value of Arterial spin-labeled (ASL) through comparison with computed tomography perfusion (CTP) in patients with chronic intracranial artery (middle cerebral artery, MCA) stenosis. MethodsTwenty-nine patients (14 female, average ages 62) were included in our study from October 2013 to August 2016. Relative cerebral blood flow (rCBF) in the MCA territory was calculated on both ASL and CTP. Patients were divided into three groups (mild, moderate and severe) based on their degree of MCA stenosis on DSA. The paired t-tests and Bland-Altman plots were used to evaluate the differences of rCBF between ASL and CTP. ResultsThere was a significant difference in rCBF between ASL and CTP for all patients (P < 0.001) and for those with severe MCA stenosis (P < 0.001). For patients with mild or moderate stenosis, there were no significant differences (P = 0.496 and 0.645, respectively). The 95% limits of agreement for all patients and those with severe stenosis were (−0.25, 0.41) and (−0.13, 0.56), respectively. For patients with mild or moderate stenosis, the values were (−0.21, 0.22) and (−0.20, 0.19). ConclusionCompared with CTP, ASL tended to overestimate the perfusion deficit in patients with severe chronic MCA stenosis. However, ASL is noninvasive, repeatable method and can be a promising clinical diagnostic tool to evaluate patients with intracranial stenosis.

Resting regional brain activity and functional connectivity varies with resting blood pressure but not muscle sympathetic nerve activity in normotensive humans

IntroductionMean arterial pressure (MAP) is tightly controlled by the brain, with the rostroventrolateral medulla (RVLM) ‐ the final output nucleus for muscle sympathetic nerve activity (MSNA) ‐ playing a particularly important role. The aim of this study was to investigate the relationships between regional cerebral blood flow (rCBF) ‐ a proxy marker of neural activity ‐ and MAP and MSNA in young, healthy normotensive subjects.MethodsPseudocontinuous arterial spin labeling (pCASL) and functional magnetic resonance imaging (fMRI) of the brain were performed immediately following a recording of MSNA and BP in 31 normotensive subjects (13 females, 18 males; mean±SE age: 23.3±3.8 y). Subjects were divided into groups with lower (78.8±1.1 mmHg, n=15) and higher (95.9±1.6 mmHg, n=16) MAP, as well as lower (7.5±0.8 bursts/min, n=16) and higher (22.3±1.9 bursts/min, n=15) MSNA.ResultsRegional cerebral blood flow correlated positively with resting MAP in the RVLM and dorsolateral pons, as well as in the insular, prefrontal and cingulate cortices. Furthermore, functional connectivity analysis revealed that the insular and prefrontal cortices displayed greater resting connectivity within the RVLM in the group with lower MAP, but not in the group with higher MAP. However, no significant differences in rCBF were found when subjects were divided on the basis of MSNA.ConclusionsThese results suggest that small differences in resting MAP are associated with significant differences in resting activity and functional connectivity within brain regions known to contribute to cardiovascular control. It remains to be seen how these relationships are affected in hypertensive individuals.Support or Funding InformationNational Health &amp; Medical Research Council of Australia (GTN1100040)This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Quantitative Changes in Cerebral Perfusion during Urinary Urgency in Women with Overactive Bladder.

Purpose To quantitatively measure changes in cerebral perfusion in select regions of interest in the brain during urinary urgency in women with overactive bladder (OAB) using arterial spin labeling (ASL). Methods Twelve women with OAB and 10 controls underwent bladder filling and rated urinary urgency (scale 0–10). ASL fMRI scans were performed (1) in the low urgency state after voiding and (2) high urgency state after drinking oral fluids. Absolute regional cerebral blood flow (rCBF) in select regions of interest was compared between the low and high urgency states. Results There were no significant differences in rCBF between the low and high urgency states in the control group. In the OAB group, rCBF (mean ± SE, ml/100 g/min) increased by 10–14% from the low to the high urgency state in the right anterior cingulate cortex (ACC) (44.56 ± 0.59 versus 49.52 ± 1.49, p < 0.05), left ACC (49.29 ± 0.85 versus 54.02 ± 1.46, p < 0.05), and left insula (50.46 ± 1.72 versus 54.99 ± 1.09, p < 0.05). Whole-brain analysis identified additional areas of activation in the right insula, right dorsolateral prefrontal cortex, and pons/midbrain area. Conclusions Urinary urgency is associated with quantitative increase in cerebral perfusion in regions of the brain associated with processing emotional response to discomfort.

Cognitive impairment and neurovascular function in patients with severe steno-occlusive disease of a main cerebral artery

ObjectivePatients with severe steno-occlusive disease of a main cerebral artery may demonstrate cognitive impairment without identification of causative lesions on magnetic resonance imaging. We investigated whether cognitive impairment in these patients is associated with regional cerebral blood flow (rCBF), leukoaraiosis, risk factors of atherosclerosis and cerebrovascular reserve (CVR), which shows so-called clinical neurovascular function. MethodsIn 65 patients with severe steno-occlusive disease of an internal carotid artery or a middle cerebral artery (MCA) and no cerebral infarction (CI), we examined cognitive function with COGNISTAT, grades of leukoaraiosis, and CBF and CVR as calculated by iodine-123-N-isopropyl-p-iodoamphetamine single photon emission computed tomography and blood data. We compared such values of the left and right sided diseases. rCBF and CVR on the affected side were compared to other side. ResultsLogistic regression analysis revealed that CVR correlated with cognitive impairment. There was no significant difference in rCBF, CVR, or COGNISTAT score when comparing the left and right sided diseases. There were good correlations between CBF or CVR of the ipsilateral MCA area and ipsilateral and contralateral other areas. ConclusionCognitive impairment is associated with CVR in the whole brain. Nonselective widespread neurovascular mild dysfunction can be a reason for cognitive impairment in patients with severe steno-occlusive disease of a main cerebral artery and no CI.

Psychosis in Machado-Joseph Disease: Clinical Correlates, Pathophysiological Discussion, and Functional Brain Imaging. Expanding the Cerebellar Cognitive Affective Syndrome.

Machado-Joseph disease (MJD) is the most common spinocerebellar ataxia worldwide with a broad range of clinical manifestations, but psychotic symptoms were not previously characterized. We investigated the psychiatric manifestations of a large cohort of Brazilian patients with MJD in an attempt to characterize the presence of psychotic symptoms. We evaluated 112 patients with clinical and molecular diagnosis of MJD from February 2008 to November 2013. Patients with psychotic symptoms were referred to psychiatric evaluation and brain perfusion single-photon emission computed tomography (SPECT) analysis. A specific scale-Positive and Negative Syndrome Scale (PANSS)-was used to characterize psychotic symptoms in MJD patients. We also performed an autopsy from one of the patients with MJD and psychotic symptoms. Five patients presented psychotic symptoms. Patients with psychotic symptoms were older and had a late onset of the disease (p < 0.05). SPECT results showed that MJD patients had significant regional cerebral blood flow (rCBF) decrease in the cerebellum bilaterally and vermis compared with healthy subjects. No significant rCBF differences were found in patients without psychotic symptoms compared to patients with psychotic symptoms. The pathological description of a patient with MJD and psychotic symptoms revealed severe loss of neuron bodies in the dentate nucleus and substantia nigra. MJD patients with a late onset of the disease and older ones are at risk to develop psychotic symptoms during the disease progression. These clinical findings may be markers for an underlying cortical-cerebellar disconnection or degeneration of specific cortical and subcortical regions that may characterize the cerebellar cognitive affective syndrome.

CT Perfusion Dynamics of Intracranial Tuberculomas.

To study perfusion characteristics of intracranial tuberculomas and analyze changes with anti tubercular treatment. Nineteen patients of histologically proven intracranial tuberculomas were included in the study of which 9 were not on antitubercular treatment and ten were on antitubercular treatment (6 patients on treatment for less than 2 months and 4 were more than 6 months). All patients underwent CT perfusion (CTP) and CTP parameters like rCBV and rCBF were obtained from entire lesion, center and capsule of lesions and compared. CTP parameters like rCBF and rCBV were significantly low in all the three ROIs in the group not on treatment compared to that of on treatment ; rCBF and rCBV of entire lesion (p=0.018 and p=0.005 respectively), capsule (p=0.045 and p=0.010 respectively) and center of the lesion (p=0.020 and p=0.009) respectively). Tuberculomas on antitubercular treatment of more than six months showed reduced rCBF and rCBV in entire lesion (p=0.01 & p=0.01 respectively), capsule (p=0.04 & p=0.03 respectively) and center (p=0.08 & p=0.05 respectively) compared to those on treatment for less than two months. Similarly tuberculomas on treatment for six months did not show significant difference in rCBF and rCBV compared to tuberculomas who were not on treatment. Tuberculomas on treatment for less than two months showed statistically increased rCBF and rCBV in entire lesion (p=0.01 & p=0.04 respectively), capsule (p=0.03 & p=0.01 respectively) and center (p= 0.03 &=0.01) compared to those not on treatment. Intracranial tuberculomas not on treatment and those on treatment for around six months show low perfusion and tuberculomas on treatment for less than two months show high perfusion. These findings suggest that serial perfusion profiles of tuberculomas on treatment could possibly be seen as surrogate markers of response to treatment.