Multiple chronic lacunes predicting early neurological deterioration and long-term functional outcomes according to TOAST classification in acute ischemic stroke.

INTRODUCTION: Studies regarding multiple chronic lacunes (MCLs) and clinical outcome according to stroke etiology are scarce. We sought to evaluate the association between MCL and short-term/long-term clinical outcomes according to stroke etiology. PATIENTS AND METHODS: We analyzed a prospectively collected stroke registry of acute ischemic stroke patients over 4 years. The enrolled patients were classified as having large artery atherosclerosis (LAA), small vessel occlusion (SVO), cardioembolic (CE) stroke, and other etiology. The early neurological deterioration (END) and favorable outcome at 3 months were assessed. RESULTS: A total of 1070 patients were enrolled. Patients with MCL had significantly more END compared to those without MCL both in total population (adjusted odds ratio (OR), 1.7; 95% confidence interval [CI], 1.1-2.5; p = 0.013*) and in the LAA group (adjusted OR, 2.3; 95% CI, 1.3-4.2, p < 0.006). Patients with MCL had a significantly lower OR for favorable outcome at 3 months compared to those without MCL both in total population (adjusted OR, 0.7; 95% CI, 0.5-1.0, p = 0.035) and in the LAA group (adjusted OR, 0.6; 95% CI, 0.3-1.0, p = 0.043). However, MCL was not associated with END or long-term functional outcome in patients with SVO, CE, or other etiology. CONCLUSIONS: The presence of MCL was an independent predictive factor for END as well as long-term poor functional outcome in acute ischemic stroke patients. These associations were only observed in patients with LAA, not in those with SVO, CE, or other etiology.

A clinical study of 288 patients with anterior cerebral artery infarction.

OBJECTIVE: Acute ischemic stroke in the territory of anterior cerebral artery (ACA) is uncommon. Therefore, large population studies evaluating ACA infarction are scarce. We sought to evaluate epidemiological and etiological characteristics of ACA infarction compared to other territorial infarctions. METHODS: We analyzed a prospectively collected stroke registry of all acute ischemic stroke patients for 19 years at two tertiary hospitals. We included patients with acute ischemic stroke caused by large vessel stenosis or occlusion including ACA, middle cerebral artery (MCA), posterior cerebral artery (PCA), and vertebrobasilar artery (VBA). RESULTS: A total of 4171 patients were enrolled. Patients with ACA infarction (N = 288) were significantly older with more females than those with MCA, PCA, or VBA infarction. There were more patients with history of prior ischemic stroke in the ACA infarction group than in other groups. The etiology of the ACA infarction was similar to those of the MCA, PCA and also the total population (66.7-71.8% of LAA and 17.9-20.9% of CE). When patients had prior ischemic stroke history, ACA infarction was more likely to be caused by LAA than MCA or PCA infarction (OR = 6.2, 95% CI 2.0-19.2, p = 0.002 and OR = 4.0, 95% CI 1.1-14.6, p = 0.038, respectively). CONCLUSIONS: Patients with ACA infarction had significantly more prior ischemic stroke than those with MCA, PCA, or VBA infarction. The etiology of ACA infarction in patients with prior ischemic stroke showed significantly more LAA than that of MCA or PCA infarction.

The Prevalence of Microembolic Signals in Transcranial Doppler Sonography With Bubble Test in Acute Ischemic Stroke.

OBJECTIVES: Transcranial Doppler ultrasound (TCD) is noninvasive and highly sensitive and specific for the diagnosis of patent foramen ovale (PFO). We evaluated the diagnostic implications of the TCD with a saline agitation test as a routine work-up for ischemic stroke patients. METHODS: A TCD bubble study was performed in all consecutive ischemic stroke patients as a routine work-up. We evaluated the prevalence of microembolic signals (MES) for each stroke etiology and the optimal number of MES for predicting the PFO-attributable stroke. RESULTS: Subjects (N = 499) with acute ischemic stroke were enrolled. A significant fraction of patients had MES during both normal respiration (5.7-44.4%) and the Valsalva maneuver (19.5-55.6%) across all stroke etiology categories. The optimal MES threshold for the diagnosis of PFO-attributable stroke confirmed by transesophageal echocardiography was 46 MES during the Valsalva maneuver (96% sensitivity and 95% specificity). Applying ≥46 MES during the Valsalva maneuver as a threshold effectively increased the ability to differentially diagnose PFO-attributable stroke from other etiologies. The number of MES during the Valsalva maneuver was negatively correlated with increasing age (r = -.108; P = .016). CONCLUSIONS: A significant fraction of patients had right to left shunt across all Trial of ORG 10172 in Acute Stroke Treatment etiologies. A threshold number of MES facilitated the differential diagnosis of PFO-attributable stroke from other etiologies, and the optimal threshold was 46 MES during the Valsalva maneuver.

The association between serum sodium level and tuberculous meningitis compared with viral and bacterial meningitis.

We evaluated the association between hyponatremia and tuberculous meningitis (TBM) with the aim of providing additional information for differential diagnosis from other types of infectious meningitis, especially viral meningitis (VM). Cross-sectional and longitudinal data involving 5026 participants older than 18 years were analyzed in the total population and a propensity-matched population. The initial and lowest sodium levels and longitudinal changes in TBM, bacterial meningitis (BM), and VM patients were compared. Participants in the TBM group were enrolled when they were diagnosed as possible, probable, or definite TBM according to the Marais' criteria. The initial serum sodium level was significantly lower in TBM patients than in BM and VM patients (136.9 ± 5.9 vs. 138.3 ± 4.7 mmol/L, p < 0.001 for TBM vs. BM, and 139.0 ± 3.1, p < 0.001 for TBM vs. VM), and it decreased significantly more steeply to lower levels in both the TBM and BM patients compared with VM patients. The lowest serum sodium level was in the order of TBM < BM < VM patients, and the change was statistically significant in all subgroups (131.8 ± 6.4, 133.1 ± 5.1, 137.4 ± 3.7, respectively, p < 0.001). Participants with lower serum sodium level were more likely to have a diagnosis of TBM rather than VM, and this association was more pronounced for the lowest sodium level than the initial sodium level [OR 4.6 (95% CI 2.4-8.8, p < 0.001)]. These findings indicate that baseline and longitudinal evaluation of serum sodium level can provide information for differential diagnosis of TBM from BM or VM.

Association Between Long-term Functional Outcome and Change in hs-CRP Level in Patients With Acute Ischemic Stroke.

BACKGROUND AND PURPOSE: Elevated high-sensitivity C-reactive protein (hs-CRP) has been suggested as a risk factor for ischemic stroke. However, the predictive value of hs-CRP for long-term outcomes is poorly defined. Therefore, we conducted this study to evaluate whether change in hs-CRP level plays a role in the prognostic value of long-term functional disability. METHODS: We studied 263 patients with acute ischemic stroke and 104 healthy controls (67.5±11.26 and 68.17±11.21 y, respectively). hs-CRP was measured on admission and on the seventh day of hospitalization. The patients were classified into 2 groups on the basis of difference in hs-CRP level from admission to the seventh day of hospitalization (group 1, hs-CRP on admission>the seventh hospital day; group 2, hs-CRP on admission

Electroencephalography in Predicting Short-Term Clinical Outcomes after Cardiac Arrest.

BACKGROUND: Early consciousness recovery after cardiac arrest (CA) is one of the most explicit and self-evident prognostic factors for clinical outcomes. We aimed to evaluate the prognostic value of electroencephalography (EEG) phenotypes according to the American Clinical Neurophysiology Society's Critical Care EEG classification for predicting early recovery after CA. METHODS: Consecutive patients admitted to the ICU after CA were enrolled. We analyzed Glasgow Coma Scale (GCS) score within 10 days after CA and evaluated mortality within 28 days according to EEG pattern subtype. RESULTS: Among the total of 71 patients, 9 had periodic discharges (PDs) EEG pattern, 4 had rhythmic delta activity (RDA), 8 had spike-and-wave (SW), 22 had low voltage, 5 had burst suppression, and 23 had other EEG patterns. Initial GCS scores, GCS scores 3 days after CA (or 3 days after targeted temperature management [TTM]), and 10 days after CA (or 10 days after TTM) were significantly different among EEG subtypes (p < 0.001, respectively) (Table 2). GCS scores were significantly higher in RDA and the other EEG group compared to the PDs, SW, low voltage, and burst suppression groups (p < 0.001). Significant group × time interactions were observed for the follow-up period between EEG phenotypes (p < 0.001) demonstrating the most increase in the other EEG pattern group. CONCLUSIONS: Consciousness states were significantly worse in the PDs, SW, burst suppression, and low-voltage groups compared to the RDA and the other EEG pattern within 10 days after CA. The degree of consciousness recovery differed significantly by EEG pattern subtype within 10 days.

Transcranial Direct Current Stimulation for the Treatment of Parkinson's Disease: Clinical and Regional Cerebral Blood Flow SPECT Outcomes.

BACKGROUND AND PURPOSE: Over the course of treatment for Parkinson's disease (PD), the clinical effects of dopaminergic medication diminish and side effects emerge. Therefore, searching for new therapeutic alternatives or complementary treatments is required. Transcranial direct current stimulation (tDCS) could potentially complement the current therapeutic armamentarium, but only a few studies have investigated the therapeutic effects of tDCS in PD. The present pilot study aimed to investigate the effects of repeated tDCS treatment on motor symptoms and regional cerebral blood flow (rCBF) in patients with PD using single photon emission computed tomography (SPECT). METHODS: Four patients with PD received tDCS to the dorsolateral prefrontal cortex two times per week (anode F3/cathode F4, 2 mA for 30 minutes) over a period of 12 months. Patients underwent brain SPECT scans and clinical motor evaluation at baseline and 12-month follow-up. For SPECT data, voxel-wise changes in rCBF were analyzed. RESULTS: There was no significant change of the motor severity scale, but the follow-up SPECT showed significant hyperperfusion in the left superior frontal gyrus medial segment and left superior parietal lobule compared to baseline (P < .001). CONCLUSIONS: This study shows that tDCS application may improve rCBF in the frontal and parietal lobes in patients with PD, suggesting beneficial effects of tDCS on brain function. Our results are preliminary and further large-scale studies are needed to confirm our findings.

Blood-brain barrier permeability assessed by perfusion computed tomography predicts hemorrhagic transformation in acute reperfusion therapy.

Hemorrhagic transformation (HT) is one of the most feared complications of acute recanalization therapies. The aim of this study was to evaluate whether blood-brain barrier permeability (BBBP) imaging can predict HT in the setting of acute recanalization therapy and to determine the sensitivity and specificity of BBBP for the prediction of HT according to the type of reperfusion therapy. We assessed a total of 46 patients who received recanalization therapy (intravenous (IV) recombinant tissue plasminogen activator (tPA), mechanical thrombectomy with a stent retriever or both) for acute ischemic stroke within the internal carotid artery or middle cerebral artery. BBBP above the threshold was significantly associated with HT after adjustment for confounding factors in all patients (OR 45.4, 95% CI 2.9~711.2, p = 0.007), patients who received IV tPA (OR 20.1, 95% CI 1.2-336.7, p = 0.037), and patients who received endovascular therapy (OR 47.2, 95% CI 1.9-1252.5, p = 0.022). The sensitivity and specificity of the initial BBBP measurement as a predictor of HT in the overall 46 patients were 80 and 71%, respectively. These values were 75 and 64% in only IV tPA group, 100 and 80% in only endovascular group, 77 and 67% in IV tPA with or without endovascular therapy group, and 86 and 76% in endovascular therapy with or without bridging IV tPA therapy group. Increased pretreatment BBBP values were significantly associated with HT after acute recanalization therapy. This correlation with HT was stronger in patients receiving endovascular mechanical thrombectomy than in patients receiving IV rtPA.

Prognostic Value of Serum D-Dimer in Noncardioembolic Ischemic Stroke.

BACKGROUND: Although D-dimer levels are significantly associated with cardioembolic infarction, the significance of D-dimer levels in relation to the severity and functional outcomes of other stroke subtypes, such as lacunar and large artery atherosclerosis infarction, remains unclear. The purpose of this study was to evaluate whether elevated initial D-dimer levels are significantly and cross-sectionally associated with poor functional outcomes at each time point during a 9-month follow-up period. We also investigated the significance of D-dimer levels in longitudinal temporal changes of functional outcomes in these patients. METHODS: We recruited 146 patients with lacunar infarction and 161 patients with large artery atherosclerosis infarction who were consecutively admitted to our hospital after acute stroke. Serum D-dimer levels were evaluated initially and the modified Rankin scale were measured initially and at 1-, 3-, 6-, and 9-month follow-up visits. RESULTS: Patients with higher D-dimer levels had significantly worse initial functional outcomes, and these worse outcomes were maintained throughout the 9-month follow-up period compared with the low D-dimer group. However, regardless of stroke subtype, D-dimer levels did not influence long-term changes in functional outcomes over the 9-month follow-up period. CONCLUSION: This study suggests that elevated D-dimer levels can be used as a surrogate marker for poor functional outcomes only during the acute stage. Further evaluation of serum D-dimer levels could provide a helpful predictive marker for stroke prognosis.

Serum D-dimer Levels Are Proportionally Associated with Left Atrial Enlargement in Patients with an Acute Ischemic Stroke due to Non-valvular Atrial Fibrillation.

Objective Left atrial enlargement (LAE) may predispose individuals to blood stasis in atrial fibrillation (AF), and thus play a crucial role in thrombogenesis. The D-dimer level is one of the surrogate markers for a hypercoagulable state and reflects thrombus formation in AF. Since the D-dimer level reflects hypercoagulability as well as thrombus and fibrin burdens, LAE could be associated with a D-dimer elevation. However, no studies have explored this association or which factors contribute to increases in the D-dimer levels in patients with AF. Therefore, we assessed whether the serum D-dimer levels are related to the left atrial volume index (LAVI) or other vascular risk factors and also evaluated the association between the D-dimer levels and the initial stroke severity. Methods Ninety-eight consecutive patients with an acute ischemic stroke and non-valvular AF (NVAF) who were anticoagulation-naïve were enrolled, and all patients were stratified into moderate-to-severe and mild neurologic deficit groups using the National Institutes of Health Stroke Scale on admission. The association between the initial serum D-dimer levels and the LAVI was evaluated in all enrolled patients, and the serum D-dimer levels were compared between the two groups. Results The patients were classified into two groups according to the severity of the neurologic deficit. In a partial correlation coefficient analysis adjusted for confounding factors, an increase in the initial serum D-dimer levels was significantly associated with LAVI (r=0.286; p=0.027). A linear regression analysis showed that a history of peripheral artery disease was the factor most strongly associated with the serum D-dimer level (t=3.90, p<0.001), followed by LAVI (t=2.37, p=0.021) and a history of congestive heart failure (t=2.16, p=0.035). The D-dimer levels were higher in the moderate-to-severe neurologic deficit group than in the mild deficit group, but this difference was not statistically significant (4.5±7.1 vs. 1.6±2.6 mg/L, p=0.068). Conclusion The serum D-dimer levels were significantly associated with LAE in anticoagulation-naïve patients with an acute ischemic stroke and NVAF.

Alteration patterns of brain glucose metabolism: comparisons of healthy controls, subjective memory impairment and mild cognitive impairment.

BACKGROUND: Some groups have focused on the detection and management of subjective memory impairment (SMI) as the stage that precedes mild cognitive impairment (MCI). However, there have been few clinical studies that have examined biomarkers of SMI to date. PURPOSE: To investigate the differences in glucose metabolism as a prodromal marker of dementia in patients with SMI, MCI, and healthy controls using brain F-18 fluoro-2-deoxyglucose positron emission tomography (FDG-PET). MATERIAL AND METHODS: Sixty-eight consecutive patients with SMI, 47 patients with MCI, and 42 age-matched healthy subjects were recruited. All subjects underwent FDG-PET and detailed neuropsychological testing. FDG-PET images were analyzed using the statistical parametric mapping (SPM) program. RESULTS: FDG-PET analysis showed glucose hypometabolism in the periventricular regions of patients with SMI and in the parietal, precentral frontal, and periventricular regions of patients with MCI compared with healthy controls. Interestingly, hypometabolism on FDG-PET was noted in the parietal and precentral frontal regions in MCI patients compared to SMI patients. CONCLUSION: The results suggest that hypometabolism in the periventricular regions as seen on FDG-PET may play a role as a predictive biomarker of pre-dementia, and the extension of reduced glucose metabolism into parietal regions likely reflects progression of cognitive deterioration.

Relationship between the hs-CRP as non-specific biomarker and Alzheimer's disease according to aging process.

BACKGROUND: Microglia are involved in immune surveillance in intact brains and become activated in response to inflammation and neurodegeneration. Microglia have different functions, neuroprotective or neurotoxic, according to aging in patients with PD. The clinical effect of microglia in patients with Alzheimer's disease (AD) is poorly defined. This prospective study was conducted to investigate the clinical effects of microglia according to the aging process in newly diagnosed AD. METHODS: We examined 532 patients with newly diagnosed AD and 119 healthy controls, and the differences in hs-CRP between these groups were investigated. The patients with AD were classified into 3 subgroups according to age of newly diagnosed AD to investigate the relationship between hs-CRP and the aging process in newly diagnosed AD. RESULTS: There was significantly higher serum high-sensitivity C-reactive protein (hs-CRP), levels in patients with AD compared with healthy controls. A post-hoc analysis of the 3 AD subgroups showed no significant differences in serum hs-CRP level between each group. CONCLUSION: We assumed that neuroinflammation play a role in the pathogenesis of AD, but found no clinical evidence that microglia senescence underlies the microglia switch from neuroprotective in young brains to neurotoxic in aged brains. To clarify the role of microglia and aging in the pathogenesis of AD, future longitudinal studies involving a large cohort are required.

Association between serum haptoglobin and the pathogenesis of Alzheimer's disease.

OBJECTIVE: Haptoglobin (Hpg) is known to have several functional properties, including antioxidant and anti-inflammatory activities. In addition, it has been shown that the pathogenesis of neurodegenerative disorders, such as Alzheimer's disease (AD), involves inflammation as well as oxidative stress. However, evidence suggesting an association between the serum Hpg level and AD is lacking. Therefore, we conducted this study in order to investigate whether serum Hpg is associated with AD. METHODS: We compared the serum Hpg levels of 121 patients with newly diagnosed AD, 58 patients with Parkinson's disease (PD) and 43 healthy controls. We also evaluated the relationship between the severity of cognitive impairment in patients with AD and the serum Hpg level. RESULTS: The mean serum Hpg level of the patients with AD was significantly higher than that of the healthy controls (p=0.042), although it was not significant different from that observed in the PD group (p=0.613). We also found a significant positive association between the serum Hpg level and the severity of cognitive impairment, as measured using several neuropsychological tests, in the patients with AD. The odds ratio (95% confidence interval) of the patients with AD grouped according to the Hpg level was 2.417 (95% confidence interval=1.134-5.149). CONCLUSION: We observed a significantly higher mean serum Hpg level among the patients with AD compared to the healthy controls. These results support the hypothesis that oxidative stress and neuroinflammatory reactions play a role in the pathogenesis of AD.

Changes in regional brain glucose metabolism measured with F-18-FDG-PET in essential tremor.

BACKGROUND: There is growing evidence that essential tremor (ET) is a multiple-system disorder. Previous PET studies in ET typically have measured brain oxygen consumption and cerebral blood flow. PURPOSE: To compare ET patients with control subjects to investigate any regional change in cerebral glucose metabolism through statistical parametric mapping (SPM) analysis of F-18-fluorodeoxyglucose positron emission tomography (F-18-FDG-PET). MATERIAL AND METHODS: We studied 17 patients with ET (17 men; mean age, 67.3 ± 4.8 years) and age-sex matched normal subjects. All subjects underwent FDG-PET imaging, and evaluated severity of tremor symptoms was measured as score on the Fahn-Tolosa-Marin rating scale (FTM). We also evaluated detailed the medical history and neurological examinations in all patients. RESULTS: The mean age of tremor onset was 57.6 ± 12.9 years and the mean FTM score was 15.1 ± 4.9. Brain FDG-PET analysis demonstrated hypometabolism in the medial frontal lobe, medial temporal lobe, and the precuneus of parietal lobe. However, there was no significant difference of glucose metabolism in the cerebellum. CONCLUSION: We propose that motor symptom of ET are caused by electrophysiological disturbances within cortical-cerebellar networks, rather than degenerative process of cerebellum, because the metabolism of the cerebellum was normal at rest. Furthermore, the abnormal glucose metabolism in the cerebral regions that do not mainly participate in motor function suggest that these regions may play a role as early markers of non-motor manifestations.

Early detection of subjective memory impairment in Parkinson's disease using cerebral perfusion SPECT.

Cognitive dysfunction is a common feature of Parkinson's disease (PD). Recent research has focused on the detection and management of subjective memory impairment (SMI) as the stage that precedes mild cognitive impairment (MCI). Nevertheless, few clinical studies have biomarkers of SMI in PD. Therefore, this study was designed to investigate differences in perfusion brain SPECT between PD with SMI (PD+SMI) and PD without SMI (PD-SMI) to identify a potential prodromal biomarker of progression to dementia in patients with PD. In this study, 30 PD patients with SMI and 24 PD patients without SMI have been recruited. All subjects underwent perfusion brain SPECT and neuropsychological testing. Brain SPECT images were analyzed by using the SPM program and comparing between patients with PD+SMI and PD-SMI. The PD+SMI and PD-SMI groups did not differ in any neuropsychological tests, except for MMSE. Despite a significant difference in MMSE scores, all scores of both groups were in the normal range. Brain SPECT analysis of PD+SMI patients showed hypoperfusion in the frontal and inferior temporal regions, anterior cingulate and thalamus compared with PD-SMI patients. This pilot study investigated the role of decreased brain perfusion SPECT findings in PD+SMI patients compared with PD-SMI patients as a predictive biomarker of pre-dementia as the stage that precedes MCI in PD. Larger, prospective studies are warranted for further investigation of the pathophysiology of neuronal systems during cognitive decline.

Brain SPECT can differentiate between essential tremor and early-stage tremor-dominant Parkinson's disease.

There are no confirmatory or diagnostic tests or tools to differentiate between essential tremor (ET) and tremor in idiopathic Parkinson's disease (PD). Although a number of imaging studies have indicated that there are differences between ET and PD, the functional imaging study findings are controversial. Therefore, we analyzed regional cerebral blood flow (CBF) by perfusion brain single-photon emission computed tomography (SPECT) to identify differences between ET and tremor-dominant Parkinson's disease (TPD). We recruited 33 patients with TPD, 16 patients with ET, and 33 healthy controls. We compared the severity of tremor symptoms by comparing the Fahn-Tolosa-Marin rating scale (FTM) score and the tremor score from Unified Parkinson's Disease Rating Scale (UPDRS) between TPD and ET patients. Subjects were evaluated by neuropsychological assessments, MRI and perfusion SPECT of the brain. Total FTM score was significantly higher in ET patients than TPD patients. However, there was no significant difference in FTM Part A scores between the two patient groups, while the scores for FTM Part B and C were significantly higher in ET patients than TPD patients. Brain SPECT analysis of the TPD group demonstrated significant hypoperfusion of both the lentiform nucleus and thalamus compared to the ET group. Brain perfusion SPECT may be a useful clinical method to differentiate between TPD and ET even during early-phase PD, because the lentiform nucleus and thalamus show differences in regional perfusion between these two groups during this time period. Additionally, we found evidence of cerebellar dysfunction in both TPT and ET.

Early diagnosis of Alzheimer's disease and Parkinson's disease associated with dementia using cerebral perfusion SPECT.

BACKGROUND: Since patterns of cognitive dysfunction in mild Parkinson's disease associated with dementia (PDD) are similar to those in mild Alzheimer's disease (AD), it is difficult to accurately differentiate between these two types of dementia in their early phases using neuropsychological tests. The purpose of the current study was to investigate differences in cerebral perfusion patterns of patients with AD and PDD at the earliest stages using single photon emission computed tomography (SPECT). METHODS: We consecutively recruited 31 patients with mild PDD, 32 patients with mild probable AD and 33 age-matched healthy subjects. All subjects underwent (99m)Tc-hexamethylpropyleneamine oxime perfusion SPECT and completed general neuropsychological tests. RESULTS: We found that both mild PDD and AD patients showed distinct hypoperfusion in frontal, parietal and temporal regions, compared with healthy subjects. More importantly, hypoperfusion in occipital and cerebellar regions was observed only in mild PDD. CONCLUSION: The observation of a significant decrease in cerebral perfusion in occipital and cerebellar regions in patients with mild PDD is likely useful to differentiate between PDD and AD at the earliest stages.

An FP-CIT PET comparison of the difference in dopaminergic neuronal loss in subtypes of early Parkinson's disease.

BACKGROUND: Patients with tremor-dominant Parkinson's disease (PD) have slower disease progression, show less cognitive decline, and have more favorable outcomes than patients with non-tremor PD. However, the pathophysiology of PD tremor remains unclear. Whether there are differences in nigrostriatal dopaminergic dysfunction between the two PD subtypes is unknown. PURPOSE: To evaluate the differences in regional dopamine transporter (DAT) density in the brain between different subtypes of early PD using FP-CIT PET/CT. MATERIAL AND METHODS: We recruited 43 patients with PD (21 tremor-dominant PD [TP] and 22 non-tremor-dominant PD [NTP]) and 18 age-matched healthy controls. All patients with PD underwent FP-CIT PET/CT imaging and evaluated Parkinsonian motor severity by using the Hoehn and Yahr stage and Part III of the Unified Parkinson's Disease Rating Scale (UPDRS). We also compared tremor and non-tremor symptoms with motor phenotype scores between two subtypes of PD. RESULTS: All patients with PD demonstrated a significantly decreased FP-CIT uptake in the putamen compared to healthy controls. Differences in putamen FP-CIT uptake versus caudate nucleus FP-CIT uptake in PD showed putamen uptake was significantly more impaired than that in the caudate nucleus. However, there was no significant difference in FP-CIT uptake in the striatum between both PD groups at the same early stage of disease. CONCLUSION: We suggest that differential of DAT uptake in the striatum did not allow for a reliable separation of subtypes into tremor-dominant and non-tremor-dominant, especially in the early stages of PD. Therefore, we assumed that many systems besides the nigrostriatal dopaminergic system are involved in the generation of tremors in PD.

Differences in cerebral perfusion according to phenotypes of essential tremor: brain perfusion SPECT study using SPM analysis.

Essential tremor (ET) is one of the most common movement disorders. However, few studies regarding the differences of pathophysiology according to phenotypes of ET have been reported. We investigated whether a functional difference occurs between ET with only a limb tremor (L-ET) and ET with only a head tremor (H-ET). We recruited 13 patients with L-ET, 10 patients with H-ET, and 33 healthy subjects. We compared the severity of tremor symptoms using the Fahn-Tolosa-Marin rating scale (FTM) to compare L-ET with H-ET. All subjects underwent magnetic resonance imaging and perfusion SPECT of the brain. The total score of FTM was significantly higher in the L-ET than in the H-ET. However, Part A in FTM did not show significant differences between the two ET groups. A brain perfusion SPECT analysis demonstrated no significant difference between L-ET and H-ET, but a regional perfusion of subjects with ET compared with healthy subjects showed hypoperfusion in the insular, cingulate gyrus, frontal lobe, and cerebellum. In conclusion, we suggested that cerebellar dysfunction might be involved in the pathogenesis of ET. In addition, we assumed that ET has the same pathogenesis in the origin of the disease, regardless of the clinical difference of ET.

Is neuroinflammation involved in the development of dementia in patients with Parkinson's disease?

OBJECTIVE: High-sensitivity C-reactive protein (hs-CRP) is an extremely sensitive systemic marker of inflammation and tissue damage, and increased levels of hs-CRP are strongly associated with inflammatory reactions. Microglia-mediated neuroinflammation has been hypothesized to play an important role in the pathogenesis of idiopathic Parkinson's disease (PD). However, the clinical value of the hs-CRP level in patients with PD is poorly defined. Therefore, we conducted this study to analyze the differences in the hs-CRP levels in PD patients with and without dementia. METHODS: We examined 72 PD patients without dementia (PDwoD) and 45 PD patients with dementia (PDD), as well as 84 control subjects. We investigated the differences in the hs-CRP and fibrinogen levels between these three groups. RESULTS: The mean hs-CRP and fibrinogen values were not significantly different between the PDwoD and PDD groups; however, these two groups had significantly higher mean hs-CRP and fibrinogen values than the control group. CONCLUSION: It is known that inflammation plays a role in the pathogenesis of PD and dementia. However, based on the results of this study, we cautiously speculate that although neuroinflammation plays a role in the development of neurodegenerative diseases, including PD and dementia, it may be unrelated to the pathogenesis of dementia in patients with PD.