[Assessment of the significance of dilated perivascular spaces and nocture arterial hypertension in the development of Alzheimer's disease]. / Otsenka znacheniya rasshirennykh perivaskulyarnykh prostranstv i nochnoi arterial'noi gipertenzii v razvitii bolezni Al'tsgeimera.

OBJECTIVE: To study the severity and localization of dilated perivascular spaces (DPVS), the levels of protein markers of amyloidosis and neurodegeneration in the cerebrospinal fluid (CSF) at different daily blood pressure (BP) profiles in patients with Alzheimer's disease (AD) and other types of cognitive impairment. MATERIAL AND METHODS: A total of 119 people, aged 53 to 92 years, including 55 patients with AD, 27 patients with vascular cognitive disorders (VCD), 19 patients with frontotemporal degeneration (FTD). All patients underwent BP monitoring for 24 hours using a standard oscillometric measurement method, lumbar puncture to assess Aß-42 and Aß-40 amyloid protein, total and phosphorylated tau protein in the CSF, magnetic resonance imaging tomography of the brain with subsequent assessment of the severity of expansion and localization of DPVS according to the G.M. Potter scale. RESULTS: In 58.3% of patients with AD, there is no adequate reduction in BP at night in comparison with patients with VCD (p<0.05). A significant degree of expansion of the DPVS turned out to be most typical for patients with AD: grade 3 was detected in 45.7% of patients, and the maximum, grade 4, was detected in 13.4%. At the same time, DPVSs were significantly more often detected in the group of subjects with insufficient reduction in diastolic BP (DBP) at night. A strong inverse correlation was established between the level of Aß-42 in the CSF and the variability of DBP at night (r= -0.92; p<0.05). The decrease in the level of Aß-42 in AD, especially at the prodromal stage, is directly related to the low variability of DBP at night, which is more characteristic of an insufficient decrease or increase in BP during night sleep. CONCLUSION: Patients with AD were characterized by an insufficient decrease in BP at night, which is associated with the severity and degree of maximum expansion of the DPVS. A decrease in the level of Aß-42 amyloid protein in the CSF strongly correlates with the variability of DBP at night.

A Novel Needle Mouse Model of Vascular Cognitive Impairment and Dementia.

Bilateral common carotid artery (CCA) stenosis (BCAS) is a useful model to mimic vascular cognitive impairment and dementia (VCID). However, current BCAS models have the disadvantages of high cost and incompatibility with magnetic resonance imaging (MRI) scanning because of metal implantation. We have established a new low-cost VCID model that better mimics human VCID and is compatible with live-animal MRI. The right and the left CCAs were temporarily ligated to 32- and 34-gauge needles with three ligations, respectively. After needle removal, CCA blood flow, cerebral blood flow, white matter injury (WMI) and cognitive function were measured. In male mice, needle removal led to ∼49.8% and ∼28.2% blood flow recovery in the right and left CCA, respectively. This model caused persistent and long-term cerebral hypoperfusion in both hemispheres (more severe in the left hemisphere), and WMI and cognitive dysfunction in ∼90% of mice, which is more reliable compared with other models. Importantly, these pathologic changes and cognitive impairments lasted for up to 24 weeks after surgery. The survival rate over 24 weeks was 81.6%. Female mice showed similar cognitive dysfunction, but a higher survival rate (91.6%) and relatively milder white matter injury. A novel, low-cost VCID model compatible with live-animal MRI with long-term outcomes was established.SIGNIFICANCE STATEMENT Bilateral common carotid artery (CCA) stenosis (BCAS) is an animal model mimicking carotid artery stenosis to study vascular cognitive impairment and dementia (VCID). However, current BCAS models have the disadvantages of high cost and incompatibility with magnetic resonance imaging (MRI) scanning due to metal implantation. We established a new asymmetric BCAS model by ligating the CCA to various needle gauges followed by an immediate needle removal. Needle removal led to moderate stenosis in the right CCA and severe stenosis in the left CCA. This needle model replicates the hallmarks of VCID well in ∼90% of mice, which is more reliable compared with other models, has ultra-low cost, and is compatible with MRI scanning in live animals. It will provide a new valuable tool and offer new insights for VCID research.

NOTCH3 variants are more common than expected in the general population and associated with stroke and vascular dementia: an analysis of 200 000 participants.

BACKGROUND: Cysteine-altering NOTCH3 variants identical to those causing the rare monogenic form of stroke, CADASIL (cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy), have been reported more common than expected in the general population, but their clinical significance and contribution to stroke and dementia risk in the community remain unclear. METHODS: Cysteine-altering NOTCH3 variants were identified in UK Biobank whole-exome sequencing data (N=200 632). Frequency of stroke, vascular dementia and other clinical features of CADASIL, and MRI white matter hyperintensity volume were compared between variant carriers and non-carriers. MRIs from those with variants were visually rated, each matched with three controls. RESULTS: Of 200 632 participants with exome sequencing data available, 443 (~1 in 450) carried 67 different cysteine-altering NOTCH3 variants. After adjustment for various covariates, NOTCH3 variant carriers had increased risk of stroke (OR: 2.33, p=0.0004) and vascular dementia (OR: 5.00, p=0.007), and increased white matter hyperintensity volume (standardised difference: 0.52, p<0.001) and white matter ultrastructural damage on diffusion MRI (standardised difference: 0.72, p<0.001). On visual analysis of MRIs from 47 carriers and 148 matched controls, variants were associated with presence of lacunes (OR: 5.97, p<0.001) and cerebral microbleeds (OR: 4.38, p<0.001). White matter hyperintensity prevalence was most increased in the anterior temporal lobes (OR: 7.65, p<0.001) and external capsule (OR: 13.32, p<0.001). CONCLUSIONS: Cysteine-changing NOTCH3 variants are more common in the general population than expected from CADASIL prevalence and are risk factors for apparently 'sporadic' stroke and vascular dementia. They are associated with MRI changes of small vessel disease, in a distribution similar to that seen in CADASIL.

An Assessment of the Relationship between Structural and Functional Imaging of Cerebrovascular Disease and Cognition-Related Fibers.

In order to assess the relationship between structural and functional imaging of cerebrovascular disease and cognition-related fibers, this paper chooses a total of 120 patients who underwent cerebral small vessel disease (CSVD) treatment at a designated hospital by this study from June 2013 to June 2018 and divides them into 3 groups according to the random number table method: vascular dementia (VaD) group, vascular cognitive impairment no dementia (VCIND) group, and noncognition impairment (NCI) group with 40 cases of patients in each group. Cognitive function measurement and imaging examination were performed for these 3 groups of patients, and the observation indicators of cognitive state examination (CSE), mental assessment scale (MAS), clock drawing test (CDT), adult intelligence scale (AIS), frontal assessment battery (FAB), verbal fluency test (VFT), trail making test (TMT), cognitive index (CI), white matter lesions (WML), third ventricle width (TVW), and frontal horn index (FHI) were tested, respectively. The results shows that the average scores of CSE, MAS, AIS, and VFT in the VaD and VCIND group are lower than those of the NCI group and the differences are statistically significant (P < 0.05); the average scores of FAB, TMT, and CI in the VaD group are higher than those of the VCIND group and the differences are also statistically significant (P < 0.05); the average scores of FHI and TVW in the VaD group are lower than those of the VCIND and NCI group with statistically significant differences (P < 0.05); the average scores of WML, CDT, and AIS in the VaD group are higher than those of the VCIND and NCI group with statistically significant differences (P < 0.05). Therefore, it is believed that the structural and functional imaging features of cerebrovascular disease are closely related to cognition-related fibers, and the incidence of white matter lesions is closely related to the degree of lesions and cognitive dysfunction of cerebral small vessel disease, in which a major risk factor for cognitive dysfunction in patients with small blood vessels is the severity of white matter lesions; brain imaging and neuropsychiatric function assessment can better understand the relationship between cerebrovascular disease and cognitive impairment. The results of this study provide a reference for the further research studies on the relationship between structural and functional imaging of cerebrovascular disease and cognition-related fibers.

Brain pathology identification using computer aided diagnostic tool: A systematic review.

Computer aided diagnostic (CAD) has become a significant tool in expanding patient quality-of-life by reducing human errors in diagnosis. CAD can expedite decision-making on complex clinical data automatically. Since brain diseases can be fatal, rapid identification of brain pathology to prolong patient life is an important research topic. Many algorithms have been proposed for efficient brain pathology identification (BPI) over the past decade. Constant refinement of the various image processing algorithms must take place to expand performance of the automatic BPI task. In this paper, a systematic survey of contemporary BPI algorithms using brain magnetic resonance imaging (MRI) is presented. A summarization of recent literature provides investigators with a helpful synopsis of the domain. Furthermore, to enhance the performance of BPI, future research directions are indicated.

Clinical utility of serum hepcidin and iron profile measurements in Alzheimer's disease.

OBJECTIVES: There are no generally accepted serum biomarkers for Alzheimer's disease (AD). We investigated the clinical usefulness of measuring the serum hepcidin levels and iron profile in patients with AD. MATERIALS & METHODS: The iron profile and hepcidin levels were measured in patients with AD (N = 70), minimal cognitive impairment (MCI, N = 39), and vascular dementia (VD, N = 25) and normal controls (N = 124). General cognitive tests were performed, and the relationships between cognition and hepcidin levels or the iron profile were assessed. RESULTS: Patients with AD had higher hepcidin values than those with MCI and VD and normal controls (median value: 39.00 vs. 30.81, 32.52, and 5.51 ng/ml, respectively, P < 0.001), and these differences were found in both men and women. The total iron-binding capacity was significantly lower in the AD group than in any other groups (308.0 vs. 332.0, 329.0, and 330.5 µg/dl, respectively, P = 0.018), and serum iron levels were lower in the AD group than controls (79.1 vs. 107.2 µg/dl, P = 0.007). Hepcidin levels were statistically significantly correlated with the clinical dementia rating (CDR, P = 0.040) with a Pearson's correlation coefficient of 0.253, and the patients with AD with a CDR value >1 had significantly higher hepcidin values than those with a CDR value of 1 (65.26 vs. 23.49 ng/ml, P = 0.020). CONCLUSION: The measurement of serum hepcidin levels and the iron profile in patients with early manifestations of cognitive functional loss might aid in the diagnosis of AD and the assessment of disease severity when combined with other diagnostic parameters.

IL-1α and IL-6 predict vascular events or death in patients with cerebral small vessel disease-Data from the SHEF-CSVD study.

PURPOSE: The natural clinical course of cerebral small vessel disease (CSVD) was not thoroughly described. The aim of this single center cohort study was to establish biochemical predictors of vascular events and death in CSVD patients during a 24-month follow-up. PATIENTS AND METHODS: A total of 130 functionally independent patients with marked MRI features of CSVD and recent lacunar stroke (n = 52,LS), vascular Parkinsonism (n = 28,VaP) or dementia (n = 50,VaD) were prospectively recruited. Serum markers of endothelial dysfunction, inflammation and hemostasis were determined at baseline. The primary outcome was defined as occurrence of death or any vascular events during the observation. RESULTS: The mean age was 72 ± 8.1 years, and 37.6% of the patients were women. The mean follow-up time was 22.3 ± 4.3 months, and 84.6% of patients had extensive white matter lesions on baseline MRI. The overall mortality rate was 6.9%, and vascular events or death occurred in 27% of the patients. Kaplan-Meier survival curves revealed no significant differences between CSVD groups (log rank p = 0.49). Cox regression analysis revealed that IL-1α (HR 1.4; 95%CI 1.09-1.8), IL-6 (1.4;1.1-2.2), hs-CRP (1.1;1.06-1.9), homocysteine (1.4;1.1-1.8), fibrinogen (1.4;1.05-2), and d-dimer (2.7;1.6-4.5) were significantly associated with the primary outcome. IL-1α (1.3;1.07-1.8), IL-6 (1.4;1.02-2.2), d-dimer (2.8;1.6-5) and homocysteine (1.4;1.1-1.8) remained significant after adjusting for age, sex and CSVD radiological markers. CONCLUSIONS: Our study demonstrated the important prognostic role of various circulation markers of inflammation in individuals with different clinical signs and radiological markers of CSVD. The strongest association occurred between IL-1α, IL-6 and recurrent stroke, other vascular events and death.

Vascular Endothelial Growth Factor remains unchanged in cerebrospinal fluid of patients with Alzheimer's disease and vascular dementia.

BACKGROUND: Increasing evidence suggests that cerebral vascular dysfunction is associated with the early stages of Alzheimer's disease (AD). Vascular endothelial growth factor (VEGF) is one of the key players involved in the development and maintenance of the vasculature. Here, we hypothesized that VEGF levels in cerebrospinal fluid (CSF) may be altered in AD patients with vascular involvement, characterized by the presence of microbleeds (MB), and in vascular dementia (VaD) patients compared to controls. METHODS: VEGF levels were determined by electrochemilumiscence Meso Scale Discovery (MULTI-SPOT Assay System) in CSF from age-matched groups of controls with subjective cognitive decline (n = 21), AD without MB (n = 25), AD with MB (n = 25), and VaD (n = 21) patients. RESULTS: The average level of VEGF in the different groups was 2.8 ± 1 pg/ml CSF. Adjusted for age and gender, no significant differences were detected between groups (p > 0.5). However, we detected a significant correlation between the concentration of VEGF in the CSF and age (r = 0.22, p = 0.03). In addition, males (n = 54) revealed higher VEGF levels in their CSF compared to females (n = 38) (males = 3.08 ± 0.769 pg/ml (mean ± SD), females = 2.6 ± 0.59; p = 0.006), indicating a gender-related regulation. CONCLUSION: Our study suggests that VEGF levels in the CSF do not reflect the cerebral vascular alterations in either AD or VaD patients. The observed associations of VEGF with age and gender may indicate that VEGF reflects normal aging and that males and females may differ in their aging process.

Role of inflammatory and hemostatic biomarkers in Alzheimer's and vascular dementia - A pilot study from a tertiary center in Northern India.

INTRODUCTION: A reliable plasma biomarker in differentiating between Alzheimer's disease (AD) and Vascular dementia (VaD) is the need of the hour, in most memory clinics. Even though there is no disease modifying treatment, it is important to know the type of dementia for both symptomatic treatment and prognostication. METHODS: Neuropsychological assessment, MRI brain, FDG-PET brain and CSF biomarkers of AD (Aß42 and total tau) were used for establishing the diagnosis of Mild Cognitive Impairment (MCI), AD or VaD. RESULTS: 68 diagnosed patients of AD/MCI/VaD were included. FDG PET brain, plasma fibrinogen, d dimer, IL6 and CRP were done in all 68 patients while 48 patients underwent CSF biomarker analysis. Sixteen patients had MCI, of which 11 were MCI-AD and 5 were MCI-VaSC. There were 41 patients with AD (Mild AD-9, Mod AD-23, Severe AD-9) and 11 patients with VaD. Alzheimer group (MCI-AD and AD) and Vascular group (MCI VaSC & VaD) consisted of 52 and 16 patients respectively. Alzheimer and Vascular groups did not exhibit significant difference in IL6 and CRP levels. Plasma fibrinogen levels were significantly higher in VaD and vascular group as compared to Alzheimer group. But MCI-VaSC was not significantly different from MCI-AD. Plasma d dimer levels were significantly higher in all vascular subgroups compared to Alzheimer subgroups except between MCI-VaSC and MCI-AD. CONCLUSION: Hemostatic biomarkers were higher in Vascular group compared to Alzheimer group whereas there was no difference in inflammatory biomarkers. But the sensitivity and specificity of fibrinogen and d-dimer were not high enough for routine clinical use. Further studies in a larger sample are required to confirm these results.

Patterns of Brain Iron Accumulation in Vascular Dementia and Alzheimer's Dementia Using Quantitative Susceptibility Mapping Imaging.

BACKGROUND: Emerging evidence suggests that the excessive accumulation of iron in subcortical and deep gray matter has been related to dementia. However, the presence and pattern of iron accumulation in vascular dementia (VaD) and Alzheimer's disease (AD) are rarely investigated. OBJECTIVE: To examine and compare the pattern and presence of brain iron accumulation of VaD and AD using quantitative susceptibility mapping (QSM). MATERIALS AND METHODS: Twelve patients with VaD, 27 patients with AD, and 18 control subjects were recruited in this institutional review-board approved study. Susceptibility maps were reconstructed from a three-dimensional multiecho spoiled gradient-echo sequence. Four regions of interest were drawn manually on QSM images, namely the globus pallidus, putamen, caudate nucleus, and pulvinar nucleus of the thalamus. Comparisons of patient demographics, and iron concentrations among the VaD, AD, and control subjects were assessed using analysis of variance and post-hoc analyses. The relationships of age and cognitive state with susceptibility values were assessed using partial correlation analysis. RESULTS: In VaD and AD, overall susceptibility values were higher than those of control subjects. A significant difference in susceptibility values was found in the putamen and caudate nucleus (p <  0.001 and p = 0.002, respectively). However, susceptibility values did not differ between VaD and AD. Age and cognitive deficit severity were not related to susceptibility values in the VaD and AD groups. CONCLUSION: Increased iron deposition in the putamen and caudate nucleus in VaD and AD patients was not associated with age or the severity of cognitive deficits. Further evaluations are needed to determine the temporal changes in iron load and their diagnostic role in dementia pathology.

Impaired attention function based on the Montréal Cognitive Assessment in vascular dementia patients with frontal hypoperfusion: The Osaki-Tajiri project.

We previously reported that the Montréal Cognitive Assessment (MoCA) was effective in the evaluation of cerebrovascular diseases. We also demonstrated that the test was effective for screening for very mild vascular dementia (VaD) in the community. Herein, we examined the effectiveness of MoCA in the assessment of patients with VaD in an outpatient clinic. Forty-four patients with VaD (National Institute of Neurological Disorders and Stroke-Association Internationale pour la Recherche et l'Enseignement en Neurosciences [NINDS-AIREN] criteria) and 58 patients with Alzheimer's disease (AD) (National Institute of Neurological and Communicative Disorders and Stroke-Alzheimer's Disease and Related Disorders Association [NINCDS-ADRDA] criteria) were compared with 67 non-demented control subjects. All were outpatients at the Tajiri Memory Clinic, Osaki-Tajiri, northern Japan. All underwent 1.5 Tesla MRI and ethyl cysteinate dimer (ECD) single photon emission computed tomography (SPECT) examinations. The SPECT images were used to classify the VaD patients into two subgroups, those with frontal hypoperfusion (F-VaD) and those without frontal hypoperfusion. The frontal hypoperfusion pattern was defined as the "P2" pattern of the Sliverman classification, with or without focal hypometabolism in other areas, based on the agreement of three neurologists who were blinded to the results of the neuropsychological examinations. Total scores and attention subscores on the MoCA were lower in the F-VaD group compared with other groups. Our results suggest that the MoCA attention subscale can detect VaD participants, particularly those with frontal hypoperfusion.

Diffusion tensor imaging changes correlate with cognition better than conventional MRI findings in patients with subcortical ischemic vascular disease.

BACKGROUND/AIMS: To investigate whether diffusion tensor imaging (DTI) is more sensitive than conventional MRI at detecting cognitive deterioration in patients with subcortical ischemic vascular disease (SIVD). METHODS: Forty-two SIVD patients had a diagnosis of no cognitive impairment (NCI), vascular cognitive impairment/no dementia or vascular dementia (VaD). Whole-brain DTI histography and routine MRI were performed on these participants. RESULTS: There were significant differences between cognitively impaired patients and NCI subjects in mean diffusivity and fractional anisotropy in either whole-brain white matter (WBWM) or in normal-appearing white matter (NAWM). All DTI indices within either WBWM or NAWM were found to be significantly correlated with both the attention-executive and memory measures in SIVD subjects. Lacune numbers and T2-weighted lesions correlated only with attention-executive measures, whereas hippocampal volumes correlated only weakly with memory measures. Whole-brain gray matter volumes correlated with Z scores for all cognitive domains but language. After VaD patients had been excluded from the analysis, cognitive measures remained significantly correlated with some of the DTI indices, but not with conventional MRI findings. CONCLUSIONS: Compared with conventional MRI, whole-brain DTI is a more reliable and sensitive technique for the early detection of cognitive impairment in SIVD patients.

Cerebroretinal microangiopathy with calcifications and cysts: demonstration of radiological progression.

Cerebroretinal microangiopathy with calcifications and cysts is a rare entity with progressive calcifications, enhancing subcortical cysts, and leukoencephalopathy. We present the oldest reported woman with this disorder, with 10 years of imaging documenting progression. This reveals (1) more profound white matter involvement than that previously reported and (2) growth and shrinkage of cysts over time, which may suggest a more complex pathogenesis than that previously theorized.

Vascular characteristics of patients with dementia.

Arterial beta stiffness index is a potential risk factor for increased stroke occurrence. Vascular component appears to be significant in both Alzheimer's disease (AD) and vascular dementia (VAD). We aimed to further explore vascular characteristics of patients with both types of cognitive decline using non-invasive neurosonological methods. There were 38 patients; 16 diagnosed with AD and 22 with VAD. Vascular risk factors were assessed and ultrasound measurements on common carotid artery (CCA) were performed using Aloka ProSound ALPHA 10 with 13 MHz linear probe. Among AD patients there were 5 with arterial hypertension (AH), 3 with atrial fibrillation (AF), 2 with diabetes mellitus (DM), 6 with hyper lipidemia and 1 smoker. Nineteen VAD patients had AH, 6 had AF, 12 had hyper lipidemia and one was diabetic. We found no statistically significant differences between groups regarding average body mass index (BMI), blood pressure, pulse pressure, intima-media thickness (IMT), CCA diameter or arterial beta stiffness indices. However, the trend of BMI increase, slight blood and pulse pressure decrease, CCA diameter increase and beta stiffness index increase was noted in VAD patients. Even though there was no significant difference found among two explored subgroups of patients with dementia, there was a tendency of greater systolic and diastolic diameters noted in VAD as well as greater stiffness, especially when measured in the right CCA. This indicates that VAD patients may have more prominent vascular changes that may help differentiate the type of dementia and further monitor these individuals. Further studies on a larger number of patients are needed support this evidence.

Higher level gait disorders in subcortical chronic vascular encephalopathy: a single photon emission computed tomography study.

BACKGROUND: the so-called higher level gait disorders include several types of gait disorders in which there are no major modifications in strength, tone, sensitivity, coordination and balance. Brain activation sites related to walking have been investigated using SPECT in humans. The aim of the study was to investigate brain activation during walking in subjects with high-level gait disorders due to chronic subcortical vascular encephalopathy. SUBJECTS: twelve patients with a chronic vascular encephalopathy were enrolled in the study. Seven subjects had apraxic gait while in the other five the gait was normal. All patients had undergone a recent cerebral magnetic resonance that revealed diffused chronic ischemic lesions within the white matter. METHODS: all 12 patients underwent a regional cerebral blood flow (rCBF) brain SPECT study with (99m)Tc-Bicisate on two separate days and under two different conditions: at rest (baseline) and while walking (functional). RESULTS: the rCBF increase induced by the treadmill test (functional-baseline), bilaterally in the medial frontal gyrus and in the anterior lobes of the cerebellum, resulted significantly (P < 0.001) lower in patients with gait apraxia versus those without it. CONCLUSIONS: this study of the brain with SPECT records the areas of perfusion deficit that appear in apraxic subjects when they walk, compared with the recordings obtained with the same investigation performed at rest.

Comparison of Alzheimer's disease with vascular dementia and non-dementia using specific voxel-based Z score maps.

OBJECTIVE: We investigated the ability to discriminate between Alzheimer's disease (AD) and vascular dementia (VaD), and between AD and non-dementia using the program "easy Z score imaging system" (eZIS) developed by Matsuda et al., for the diagnosis of very early AD. METHODS: Of 201 patients, we investigated 12 patients with AD, 10 with VaD, and 9 with non-dementia, who underwent brain perfusion single-photon emission computed tomography by technetium-99m ethyl cysteinate dimer (99mTc-ECD) between February 2005 and September 2006. The sensitivity and specificity of the indicators of specific volume of interest (VOI) analysis, namely, severity, extent, and ratio were evaluated for the distinction of AD from VaD and non-dementia. RESULTS: There was a significant difference in all the criteria for severity, extent, and ratio between AD and non-dementia cases and in the ratio between AD and VaD. Between AD and non-dementia, the sensitivity and specificity of severity were 100% and 45%, respectively, using the cutoff value of 1.19. When using the cutoff value of 14.2 for extent, the sensitivity and specificity were both 100%. Using the cutoff value of 2.22 for ratio, the sensitivity of 42% and specificity of 100% were demonstrated. When comparing AD with VaD, using the cutoff value of 2.22 for ratio, the sensitivity and specificity were 42% and 100%, respectively. Using the cutoff value of 1.5 for ratio, the sensitivity and specificity between AD and VaD were 92% and 80%, respectively, thereby showing the best results. CONCLUSIONS: The specific VOI analysis program of AD using specific voxel-based Z score maps is not influenced by interobserver differences among radiologists and is useful to discriminate AD from VaD and non-dementia. However, the setting of the cutoff value at each institution and comparison with original and eZIS images are suggested to distinguish better AD from VaD.

Differentiation of early-stage Alzheimer's disease from other types of dementia using brain perfusion single photon emission computed tomography with easy Z-score imaging system analysis.

INTRODUCTION: We performed brain perfusion single photon emission computed tomography (SPECT) to evaluate computer-assisted automated discrimination of early Alzheimer's disease (AD) from other types of dementia using the easy Z-score imaging system (eZIS). SUBJECTS AND METHODS: eZIS analysis of brain perfusion SPECT images was used in patients with early AD, vascular dementia (VD), mixed dementia (VD + AD), frontotemporal dementia (FTD), dementia with Lewy bodies (DLB), and normal controls. Significant changes in regional cerebral blood flow (rCBF) in the volume of interest were assessed in the posterior cingulate gyrus, precuneus and parietal cortices; the severity and extent of decreases in rCBF and the ratio of the extent of the decrease in rCBF to the decrease in whole-brain blood flow (rCBF ratio) were determined. RESULTS: The severity of the decrease in rCBF in AD patients was significantly greater than in VD and FTD patients and controls. The extent of the decrease in rCBF in AD patients was significantly greater than in FTD patients and controls. The rCBF ratio in AD patients was higher than in VD and FTD patients and controls. CONCLUSION: The eZIS indices, especially the rCBF ratio, may be useful in establishing the differential diagnosis between early-stage AD and FTD or VD, but the differentiation of AD from VD + AD or DLB remains difficult.

SPECT revealed cortical dysfunction in a patient who had genetically definite megalencephalic leukoencephalopathy with subcortical cysts.

We describe the findings on single photon emission computed tomography (SPECT) in a patient who had genetically definite megalencephalic leukoencephalopathy with subcortical cysts. Technetium-99m-ethyl cysteinate dimer SPECT revealed hypoperfusion in the cerebral white matter, which had shown high signal intensity on magnetic resonance imaging (MRI) T2 images. Hypoperfusion was also unexpectedly found in the frontal cortices, which showed no abnormalities on MRI. This frontal abnormality corresponded clinically to a low score on the frontal assessment battery. Decreased GABA receptor density as suggested by (123)I-Iomazenil SPECT provided further evidence of cortical neuron dysfunction. Although confirmation must await future larger-scale SPECT and functional studies, our findings suggest that SPECT can be used to non-invasively monitor in vivo cortical function in this disease.

Neuroradiological findings in vascular dementia.

INTRODUCTION: There are multiple diagnostic criteria for vascular dementia (VaD) that may define different populations. Utilizing the criteria of the National Institute of Neurological Disorders and Stroke and Association Internationale pour la Recherche et l'Enseignement en Neurosciences (NINDS-AIREN) has provided improved consistency in the diagnosis of VaD. The criteria include a table listing brain imaging lesions associated with VaD. METHODS: The different neuroradiological aspects of the criteria are reviewed based on the imaging data from an ongoing large-scale clinical trial testing a new treatment for VaD. The NINDS-AIREN criteria were applied by a centralized imaging rater to determine eligibility for enrollment in 1,202 patients using brain CT or MRI. RESULTS: Based on the above data set, the neuroradiological features that are associated with VaD and that can result from cerebral small-vessel disease with extensive leukoencephalopathy or lacunae (basal ganglia or frontal white matter), or may be the consequence of single strategically located infarcts or multiple infarcts in large-vessel territories, are illustrated. These features may also be the consequence of global cerebral hypoperfusion, intracerebral hemorrhage, or other mechanisms such as genetically determined arteriopathies. CONCLUSION: Neuroimaging confirmation of cerebrovascular disease in VaD provides information about the topography and severity of vascular lesions. Neuroimaging may also assist with the differential diagnosis of dementia associated with normal pressure hydrocephalus, chronic subdural hematoma, arteriovenous malformation or tumoral diseases.

Patterns of single photon emission tomography (SPECT) among patients with dementia in the memory clinic at Siriraj Hospital.

OBJECTIVE: The authors hypothesized that there is a pattern difference in cerebralperfusion of the 99-Technitium L, L-ethyl cysteinate dimer Single Photon Emission Computer Tomography (99-Tc ECD SPECT) between mild and moderate to severe dementia. MATERIAL AND METHOD: The authors reported a retrospective study in the Memory Clinic, Siriraj Hospital between January 2001 and October 2003 including only patients with Alzheimer's disease, vascular dementia, and mixed dementia. Clinical dementia rating (CDR) was used to document dementia severity. Patterns of hypoperfusion were classified into no definite hypoperfusion, regional hypoperfusion, and diffused hypoperfusion. RESULTS: One hundred and seven patients were included in the present study. Only mean Thai Mental State Examination (TMSE) score was different between the two groups. There was no significant correlation between pattern of hypoperfusion in brain SPECT and severity of dementia. CONCLUSION: The authors cannot demonstrate the pattern of hypoperfusion of 99-Tc ECD SPECT among patients' difference in dementia severity.