Alterations in driving ability and their relationship with morphometric magnetic resonance imaging indicators in patients with amnestic mild cognitive impairment and Alzheimer's disease

BACKGROUND

Drivers with dementia are at a higher risk of motor vehicle accidents. The characteristics of driving behaviour of patients with mild cognitive impairment (MCI) and Alzheimer's disease (AD) have not been fully elucidated. We investigated driving ability and its relationship with cognitive function and magnetic resonance imaging (MRI) morphometry indicators.

METHODS

The driving abilities of 19 patients with AD and 11 with amnestic MCI (aMCI) were evaluated using a driving simulator. The association between each driving ability parameter and the Mini-Mental State Examination (MMSE) score or voxel-based specific regional analysis system for AD (VSRAD) was assessed.

RESULTS

Patients with AD made a significantly higher number of operational errors than those with aMCI in attention allocation in the complex task test (P = 0.0008). The number of operational errors in attention allocation in the complex task test significantly and negatively correlated with MMSE scores in all participants (r = -0.4354, P = 0.0162). The decision time in the selective reaction test significantly and positively correlated with the severity and extent of medial temporal structural atrophy (r = 0.4807, P = 0.0372; r = 0.4862, P = 0.0348; respectively).

CONCLUSION

An increase in the operational errors for attention allocation in the complex task test could be a potential indicator of progression from aMCI to AD. Atrophy of the medial temporal structures could be a potential predictor of impaired judgement in driving performance in aMCI and AD. A driving simulator could be useful for evaluating the driving abilities of individuals with aMCI and AD.

Superficial small cerebellar infarcts in cerebral amyloid angiopathy on 3 T MRI: A preliminary study

BACKGROUND

Strictly superficial cerebellar microbleeds and cerebellar superficial siderosis have been considered markers of advanced cerebral amyloid angiopathy (CAA), but there are few studies on cerebellar ischemic lesions in CAA. We investigated the presence of superficial small cerebellar infarct (SCI) ≤15 mm and its relation to magnetic resonance imaging (MRI) markers in patients with probable CAA.

METHODS

Eighty patients with probable CAA were retrospectively evaluated. The presence of superficial SCIs was examined, along with cerebellar microbleeds and cerebellar superficial siderosis, using 3-T MRI. Lobar cerebral microbleeds, cortical superficial siderosis (cSS), enlargement of the perivascular space in the centrum semiovale, and white matter hyperintensity were assessed and the total CAA-small vessel disease (SVD) score was calculated.

RESULTS

Nine of the 80 patients (11.3%) had a total of 16 superficial SCIs. By tentatively defining SCI <4 mm as cerebellar microinfarcts, 8 out of 16 (50%) superficial SCIs corresponded to cerebellar microinfarcts. The total CAA-SVD score was significantly higher in patients with superficial SCIs (p = 0.01). The prevalence of cSS (p = 0.018), cortical cerebral microinfarct (p = 0.034), and superficial cerebellar microbleeds (p = 0.006) was significantly higher in patients with superficial SCIs. The number of superficial cerebellar microbleeds was also significantly higher in patients with superficial SCIs (p = 0.001).

CONCLUSIONS

Our results suggest that in patients with CAA, superficial SCIs (including microinfarcts) on MRI may indicate more severe, advanced-stage CAA. These preliminary findings should be verified by larger prospective studies in the future.

A multicenter, single-arm, phase II clinical trial of adrenomedullin in patients with cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy

Background

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL), the most common form of hereditary cerebral small vessel disease (SVD), currently lacks disease-modifying treatments. Adrenomedullin (AM), a vasoactive peptide with angiogenic, vasodilatory, anti-inflammatory, and anti-oxidative properties, shows potential effects on the neuro-glial-vascular unit.

Objective

The AdrenoMedullin for CADASIL (AMCAD) study aims to assess the efficacy and safety of AM in patients with CADASIL.

Sample size

Overall, 60 patients will be recruited.

Methods

The AMCAD is a multicenter, investigator-initiated, single-arm phase II trial. Patients with a confirmed CADASIL diagnosis, based on NOTCH3 genetic testing, will receive an 8-h AM treatment (15 ng/kg/min) for 14 days following a baseline assessment (from day 1 to day 14). Follow-up evaluations will be performed on days 15, 28, 90, and 180.

Study outcomes

The primary endpoint is the cerebral blood flow change rate in the frontal cortex, evaluated using arterial spin labeling magnetic resonance imaging, from baseline to day 28. Summary statistics, 95% confidence intervals, and a one-sample t-test will be used for analysis.

Conclusion

The AMCAD study aims to represent the therapeutic potential of AM in patients with CADASIL, addressing an unmet medical need in this challenging condition.

Clinical Trial Registration

jRCT 2,051,210,117 (https://jrct.niph.go.jp/en-latest-detail/jRCT2051210117).

Super Formula for Soluble C-Type Lectin-Like Receptor 2 × D-Dimer in Patients With Acute Cerebral Infarction

Acute cerebral infarction (ACI) includes atherosclerotic and cardiogenic ACI and involves a thrombotic state, requiring antithrombotic treatment. However, the thrombotic state in ACI cannot be evaluated using routine hemostatic examinations. Plasma soluble C-type lectin-like receptor 2 (sCLEC-2) and D-dimer levels were measured in patients with ACI. Plasma sCLEC-2 and D-dimer levels were significantly higher in patients with ACI than in those without it. The sCLEC-2 × D-dimer formula was significantly higher in patients with ACI than in those without it. A receiver operating characteristic curve showed a high sensitivity, area under the curve, and odds for diagnosing ACI in the sCLEC-2 × D-dimer formula. Although the sCLEC-2 and D-dimer levels were useful for the differential diagnosis between cardiogenic and atherosclerotic ACI, the sCLEC-2 × D-dimer formula was not useful. sCLEC2 and D-dimer levels are useful for the diagnosis of ACI and the sCLEC2 × D-dimer formula can enhance the diagnostic ability of ACI, and sCLEC2 and D-dimer levels may be useful for differentiating between atherosclerotic and cardioembolic ACI.

Efficacy and Safety of Cilostazol in Mild Cognitive Impairment: A Randomized Clinical Trial

Importance

Recent evidence indicates the efficacy of β-amyloid immunotherapy for the treatment of Alzheimer disease, highlighting the need to promote β-amyloid removal from the brain. Cilostazol, a selective type 3 phosphodiesterase inhibitor, promotes such clearance by facilitating intramural periarterial drainage.

Objective

To determine the safety and efficacy of cilostazol in mild cognitive impairment.

Design, Setting, and Participants

The COMCID trial (A Trial of Cilostazol for Prevention of Conversion from Mild Cognitive Impairment to Dementia) was an investigator-initiated, double-blind, phase 2 randomized clinical trial. Adult participants were registered between May 25, 2015, and March 31, 2018, and received placebo or cilostazol for up to 96 weeks. Participants were treated in the National Cerebral and Cardiovascular Center and 14 other regional core hospitals in Japan. Patients with mild cognitive impairment with Mini-Mental State Examination (MMSE) scores of 22 to 28 points (on a scale of 0 to 30, with lower scores indicating greater cognitive impairment) and Clinical Dementia Rating scores of 0.5 points (on a scale of 0, 0.5, 1, 2, and 3, with higher scores indicating more severe dementia) were enrolled. The data were analyzed from May 1, 2020, to December 1, 2020.

Interventions

The participants were treated with placebo, 1 tablet twice daily, or cilostazol, 50 mg twice daily, for up to 96 weeks.

Main Outcomes and Measures

The primary end point was the change in the total MMSE score from baseline to the final observation. Safety analyses included all adverse events.

Results

The full analysis set included 159 patients (66 [41.5%] male; mean [SD] age, 75.6 [5.2] years) who received placebo or cilostazol at least once. There was no statistically significant difference between the placebo and cilostazol groups for the primary outcome. The least-squares mean (SE) changes in the MMSE scores among patients receiving placebo were -0.1 (0.3) at the 24-week visit, -0.8 (0.3) at 48 weeks, -1.2 (0.4) at 72 weeks, and -1.3 (0.4) at 96 weeks. Among those receiving cilostazol, the least-squares mean (SE) changes in MMSE scores were -0.6 (0.3) at 24 weeks, -1.0 (0.3) at 48 weeks, -1.1 (0.4) at 72 weeks, and -1.8 (0.4) at 96 weeks. Two patients (2.5%) in the placebo group and 3 patients (3.8%) in the cilostazol group withdrew owing to adverse effects. There was 1 case of subdural hematoma in the cilostazol group, which may have been related to the cilostazol treatment; the patient was successfully treated surgically.

Conclusions and Relevance

In this randomized clinical trial, cilostazol was well tolerated, although it did not prevent cognitive decline. The efficacy of cilostazol should be tested in future trials.

Trial Registration

ClinicalTrials.gov Identifier: NCT02491268.

A brief overview of a mouse model of cerebral hypoperfusion by bilateral carotid artery stenosis

Vascular cognitive impairment (VCI) refers to all forms of cognitive disorder related to cerebrovascular diseases, including vascular mild cognitive impairment, post-stroke dementia, multi-infarct dementia, subcortical ischemic vascular dementia (SIVD), and mixed dementia. Among the causes of VCI, more attention has been paid to SIVD because the causative cerebral small vessel pathologies are frequently observed in elderly people and because the gradual progression of cognitive decline often mimics Alzheimer's disease. In most cases, small vessel diseases are accompanied by cerebral hypoperfusion. In mice, prolonged cerebral hypoperfusion is induced by bilateral carotid artery stenosis (BCAS) with surgically implanted metal micro-coils. This cerebral hypoperfusion BCAS model was proposed as a SIVD mouse model in 2004, and the spreading use of this mouse SIVD model has provided novel data regarding cognitive dysfunction and histological/genetic changes by cerebral hypoperfusion. Oxidative stress, microvascular injury, excitotoxicity, blood-brain barrier dysfunction, and secondary inflammation may be the main mechanisms of brain damage due to prolonged cerebral hypoperfusion, and some potential therapeutic targets for SIVD have been proposed by using transgenic mice or clinically used drugs in BCAS studies. This review article overviews findings from the studies that used this hypoperfused-SIVD mouse model, which were published between 2004 and 2021.

Pulvinar quantitative susceptibility mapping predicts visual hallucinations post-deep brain stimulation in Parkinson's disease

PURPOSE

We have reported the relationship between low pulvinar nuclei (PN) intensity in susceptibility-weighted imaging and the appearance of visual hallucinations and cognitive function. The aim of the study was to examine the changes in the quantitative susceptibility mapping (QSM) in patients with Parkinson's disease (PD) who underwent deep brain stimulation (DBS) and verify whether the PN susceptibility value (SV) on QSM can predict visual hallucination and cognitive changes after DBS.

METHODS

This study examined 24 patients with PD who underwent DBS along with QSM imaging on magnetic resonance imaging (MRI). All MRIs were performed within 3 months before surgery. The PN SV was further assessed based on the QSM. Then, associations were examined among cognitive changes, hallucination, and PN SV. The cognitive function of the patient was compared immediately before surgery and at 1 year postoperatively.

RESULTS

Visual hallucinations were observed in seven patients during the follow-up period. The PN SV was ≥0.045 ppm in nine patients with PD, and six of them had visual hallucinations, whereas only one of 15 patients with PD with SV of <0.045 ppm had visual hallucinations (Fisher's exact test, p = .0037).

CONCLUSIONS

The SV of >0.045 ppm at the PN in QSM in patients with PD may provide useful information suggesting visual hallucination and cognitive deterioration after DBS treatment.

Magnetic resonance imaging and neuropsychological findings for predicting of cognitive deterioration in memory clinic patients

Objective

The severity of cerebral small vessel disease (SVD) on magnetic resonance imaging (MRI) has been assessed using hypertensive arteriopathy SVD and cerebral amyloid angiopathy (CAA)-SVD scores. In addition, we reported the modified CAA-SVD score including cortical microinfarcts and posterior dominant white matter hyperintensity. Each SVD score has been associated with cognitive function, but the longitudinal changes remain unclear. Therefore, this study prospectively examined the prognostic value of each SVD score, imaging findings of cerebral SVD, and neuropsychological assessment.

Methods

This study included 29 patients diagnosed with mild cognitive impairment or mild dementia at memory clinic in our hospital, who underwent clinical dementia rating (CDR) and brain MRI (3D-fluid attenuated inversion recovery, 3D-double inversion recovery, and susceptibility-weighted imaging) at baseline and 1 year later. Each SVD score and neuropsychological tests including the Mini-Mental State Examination, Japanese Raven's Colored Progressive Matrices, Trail Making Test -A/-B, and the Rivermead Behavioral Memory Test were evaluated at baseline and 1 year later.

Results

Twenty patients had unchanged CDR (group A), while nine patients had worsened CDR (group B) after 1 year. At baseline, there was no significant difference in each SVD score; after 1 year, group B had significantly increased CAA-SVD and modified CAA-SVD scores. Group B also showed a significantly higher number of lobar microbleeds than group A at baseline. Furthermore, group B had significantly longer Japanese Raven's Colored Progressive Matrices and Trail Making test-A times at baseline. After 1 year, group B had significantly lower Mini-Mental State Examination, Japanese Raven's Colored Progressive Matrices, and Rivermead Behavioral Memory Test scores and significantly fewer word fluency (letters).

Conclusion

Patients with worsened CDR 1 year after had a higher number of lobar microbleeds and prolonged psychomotor speed at baseline. These findings may become predictors of cognitive deterioration in patients who visit memory clinics.

Identifying and Characterizing People with Dementia Not Accessing the Japanese Community-Based Integrated Care System Using Health Insurance Claims Data

Objective In the Japanese Community-Based Integrated Care System (CBICS), access to formal care services is based on voluntary consultations mainly from the families of people with dementia (PWD). The problem is that some people need services but do not consult their municipalities for various reasons. The purpose of this study is to examine the possibility of using health insurance claims data to identify and characterize these PWD. Methods Using health insurance claims data, we selected PWD prescribed with anti-dementia drugs. Of them, excluding those with a usage history of long-term care insurance services or other formal services, facility residents and deaths, we identified PWD not accessing the CBICS. We conducted a visit survey on their status, home care environment and reasons for not accessing services, a proposal for using services and a one-year follow-up. Result Based on the data of 1,809 late-stage elderly who resided in the Tamaki-cho, a town in Mie Prefecture, Japan, for a 2-month period, 16 PWD not accessing the CBICS were identified, and 15 PWD and their families participated in this study. Ten were men and 13 were physically and cognitively relatively independent. All lived with a family caregiver and refused services. Ten families needed but had not accessed the services due to refusal by PWD and other reasons. As a result, seven of these PWD started using long-term care insurance services or dementia prevention services. Conclusion PWD not accessing the CBICS can be identified using health insurance claims data. The results proved that the municipality has a cost-effective way of providing their services to PWD and their families, even if they have never consulted voluntarily.

The Detection of Hypercoagulability in Patients with Acute Cerebral Infarction Using a Clot Waveform Analysis

A few studies concerning hypercoagulable states have sufficiently been reported in patients with acute cerebral infarction (ACI), as ACI is generally considered to be caused by platelet activation. Clot waveform analyses (CWA) for activated partial thromboplastin time (APTT) and small amount of tissue factor FIX activation assay (sTF/FIXa) were examined in 108 patients with ACI, 61 patients without ACI, and 20 healthy volunteers. CWA-APTT and CWA-sTF/FIXa showed that the peak heights were significantly higher in ACI patients without anticoagulant therapy than in healthy volunteers. Absorbance exceeding 78.1 mm on the 1^st DPH in the CWA-sTF/FIXa showed the highest odds ratio for ACI. The peak heights were significantly lower in the CWA-sTF/FIXa of ACI patients receiving argatroban therapy than in those of ACI patients without anticoagulant therapy. CWA can suggest a hypercoagulable state in ACI patients and may be useful for monitoring the need for anticoagulant therapy.

Association between behavioral and psychological symptoms and cerebral small vessel disease MRI findings in memory clinic patients

Objectives

Cerebral small vessel disease (SVD) is commonly observed among elderly individuals with cognitive impairment and has been recognized as a vascular contributor to dementia and behavioral and psychological symptoms (BPS), however, the relationship between BPS and SVD burden remains unclear.

Methods

We prospectively recruited 42 patients with mild cognitive impairment (MCI) or mild dementia from the memory clinic in our hospital, who were assigned to either a clinical dementia rating (CDR) of 0.5 or 1.0, respectively. The presence of BPS was determined through interviews with caregivers. The patients underwent brain MRI and three types of SVD scores, total, cerebral amyloid angiopathy (CAA), and modified CAA, were assigned. Patients were also evaluated through various neuropsychological assessments.

Results

The CDR was significantly higher in patients with BPS (p = 0.001). The use of antihypertensive agents was significantly higher in patients without BPS (p = 0.038). The time taken to complete trail making test set-A was also significantly longer in patients with BPS (p = 0.037). There was no significant difference in total SVD and CAA-SVD score (p = 0.745, and 0.096) and the modified CAA-SVD score was significantly higher in patients with BPS (p = 0.046). In addition, the number of total CMBs and lobar CMBs was significantly higher in patients with BPS (p = 0.001 and 0.001). Receiver operating characteristic curves for BPS showed that for modified CAA-SVD, a cutoff score of 3.5 showed 46.7% sensitivity and 81.5% specificity. Meanwhile, for the total number of cerebral microbleeds (CMBs), a cut-off score of 2.5 showed 80.0% sensitivity and 77.8% specificity and for the number of lobar CMBs, a cut-off score of 2.5 showed 73.3% sensitivity and 77.8% specificity.

Conclusion

Overall, patients with BPS showed worse CDRs, reduced psychomotor speed, higher modified CAA-SVD scores, larger numbers of total and lobar CMBs. We propose that severe modified CAA scores and higher numbers of total and lobar CMBs are potential risk factors for BPS in patients with mild dementia or MCI. Therefore, by preventing these MRI lesions, the risk of BPS may be mitigated.

Deep Brain Stimulation in a Patient with Parkinson's Disease and Cortical Superficial Siderosis

Cortical superficial siderosis (cSS) is a rare condition that is regarded as a potential magnetic resonance marker of cerebral amyloid angiopathy (CAA). We describe the case of a 68-year-old man with cSS and Parkinson's disease (PD) who subsequently exhibited incidental microhemorrhages, which were only detected on magnetic resonance imaging (MRI), at one week after deep brain stimulation (DBS) surgery. cSS is now considered to be a significant risk factor for CAA and future bleeding. Therefore, because DBS surgery is invasive and may increase the risk of intracerebral hemorrhage, the procedure should be performed carefully when managing patients with PD and CAA.

Imaging Characteristics for Predicting Cognitive Impairment in Patients With Cerebral Autosomal Dominant Arteriopathy With Subcortical Infarcts and Leukoencephalopathy

Objectives

Patients with cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) show various clinical symptoms, including migraine, recurrent stroke, and cognitive impairment. We investigated the associations between magnetic resonance imaging (MRI) markers of small vessel disease and neuropsychological tests and identified the MRI characteristics for predicting cognitive impairment in patients with CADASIL.

Methods

Subjects included 60 CADASIL patients diagnosed with genetic tests and registered in the Japanese CADASIL REDCap database between June 2016 and December 2020. Patient information including clinical data, modified Rankin Scale (mRS); MRI findings of small vessel disease including periventricular and deep white matter lesions (WML), lacunar infarcts, and cerebral microbleeds (CMBs); and neuropsychological tests, including the Japanese version of the Mini-Mental State Examination (MMSE), the Japanese version of the Montreal Cognitive Assessment (MoCA-J), and the Frontal Assessment Battery (FAB), were evaluated.

Results

Data from 44 CADASIL patients were eligible for this study, compared between patients with and without dementia. Regarding the neuroimaging findings, the Fazekas score of periventricular and deep WML was higher in patients with dementia (periventricular, p = 0.003; deep, p = 0.009). The number of lacunar infarcts was higher in patients with dementia (p = 0.001). The standardized partial regression coefficient (SPRC) in MoCA-J was 0.826 (95% CI, 0.723-0.942; p = 0.005) for the number of CMBs. The SPRC in MMSE was 0.826 (95% CI, 0.719-0.949; p = 0.007) for the number of CMBs. The SPRC for FAB decreased significantly to 0.728 (95% CI, 0.551-0.960; p = 0.024) for the number of lacunar infarcts. Receiver operating characteristic (ROC) curves for dementia showed that in the number of lacunar infarcts, a cut-off score of 5.5 showed 90.9% sensitivity and 61.1% specificity. For the number of CMBs, a cut-off score of 18.5 showed 45.5% sensitivity and 100% specificity.

Conclusion

The characteristic MRI findings were that CADASIL patients with dementia had severe WML, both periventricular and deep, and a larger number of lacunar infarcts than those without dementia. The risk of dementia may be associated with ≥ 6 lacunar infarcts, ≥19 CMBs, or a Fazekas scale score of 3 in periventricular and deep WML.

Endothelial expression of human amyloid precursor protein leads to amyloid β in the blood and induces cerebral amyloid angiopathy in knock-in mice

The deposition of amyloid β (Aβ) in blood vessels of the brain, known as cerebral amyloid angiopathy (CAA), is observed in most Alzheimer's disease (AD) patients. Compared with the pathology of CAA in humans, the pathology in most mouse models of AD is not as evident, making it difficult to examine the contribution of CAA to the pathogenesis of AD. On the basis of biochemical analyses that showed blood levels of soluble amyloid precursor protein (sAPP) in rats and mice were markedly lower than those measured in human samples, we hypothesized that endothelial APP expression would be markedly lower in rodents, and subsequently generated mice that specifically express human wild type APP (APP770) in endothelial cells. The resulting EC-APP770⁺ mice exhibited increased levels of serum Aβ and sAPP, indicating that endothelial APP makes a critical contribution to blood Aβ levels. Even though aged EC-APP770⁺ mice did not exhibit Aβ deposition in the cortical blood vessels, crossing these animals with APP knock-in mice (App^NL-F/NL-F) led to an expanded CAA pathology, as evidenced by increased amounts of amyloid accumulated in the cortical blood vessels. These results highlight an overlooked interplay between neuronal and endothelial APP in brain vascular Aβ deposition. We propose that these EC-APP770⁺:App^NL-F/NL-F mice may be useful to study the basic molecular mechanisms behind the possible breakdown of the blood-brain barrier upon administration of anti-Aβ antibodies.

High Mobility Group A1 Regulates Transcription Levels of Oligodendrocyte Marker Genes in Cultured Oligodendrocyte Precursor Cells

Oligodendrocyte precursor cells (OPCs) serve as progenitor cells of terminally differentiated oligodendrocytes. Past studies have confirmed the importance of epigenetic system in OPC differentiation to oligodendrocytes. High mobility group A1 (HMGA1) is a small non-histone nuclear protein that binds DNA and modifies the chromatin conformational state. However, it is still completely unknown about the roles of HMGA1 in the process of OPC differentiation. In this study, we prepared primary OPC cultures from the neonatal rat cortex and examined whether the loss- and gain-of-function of HMGA1 would change the mRNA levels of oligodendrocyte markers, such as Cnp, Mbp, Myrf, and Plp during the process of OPC differentiation. In our system, the mRNA levels of Cnp, Mbp, Myrf, and Plp increased depending on the oligodendrocyte maturation step, but the level of Hmga1 mRNA decreased. When HMGA1 was knocked down by a siRNA approach, the mRNA levels of Cnp, Mbp, Myrf, and Plp were smaller in OPCs with Hmga1 siRNA compared to the ones in the control OPCs. On the contrary, when HMGA1 expression was increased by transfection of the Hmga1 plasmid, the mRNA levels of Cnp, Mbp, Myrf, and Plp were slightly larger compared to the ones in the control OPCs. These data may suggest that HMGA1 participates in the process of OPC differentiation by regulating the mRNA expression level of myelin-related genes.

Cerebral Microbleeds With Atrial Fibrillation After Ablation Therapy

Background

The prevalence of cerebral microbleeds (CMBs) is significantly higher in patients with atrial fibrillation (AF) than in those without AF. CMBs in patients with AF have been reported to be primarily of the lobar type, but the exact cause of this remains unknown. We investigated the possibility that hemorrhagic transformation of embolic microinfarction can account for de novo lobar CMBs.

Methods

A total of 101 patients who underwent ablation therapy for AF were prospectively registered, and 72 patients completed the assessment with MRI 6 months after catheter ablation. Brain MRI, including diffusion-weighted imaging (DWI) and susceptibility-weighted imaging (SWI), were examined at 1–3 days (baseline) and 6 months after catheter ablation. We quantitatively evaluated the spatial and temporal distribution of embolic microinfarctions and de novo CMBs.

Results

Of the 101 patients, 68 were enrolled in this study. Fifty-nine patients (86.8%) showed embolic microinfarctions on baseline DWI immediately after catheter ablation. There were 137 CMBs in SWI, and 96 CMBs were of the lobar type. Six months later, there were 208 CMBs, including 71 de novo CMBs, and 60 of 71 (84.5%) were of the lobar type. Of the 71 de novo CMBs, 56 (78.9%) corresponded to the location of previous embolic microinfarctions found on baseline DWI. The platelet count was significantly lower and hematocrit/hemoglobin and Fazekas score were higher in the group with de novo CMBs than in the group without de novo CMBs.

Conclusion

De novo CMBs frequently appeared after catheter ablation therapy. Our results suggest that embolic microinfarction can cause lobar CMBs.

Miller Fisher syndrome following BNT162b2 mRNA coronavirus 2019 vaccination

Background

The coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), began in late 2019. One of the vaccines approved against COVID-19 is the BNT162b2 mRNA COVID-19 vaccine (Pfizer/BioNTech).

Case presentation

We present the case of a 71-year-old man with no history of the SARS-CoV-2 infection or any recent viral or bacterial illnesses who presented with bilateral oculomotor palsy and limb ataxia after BNT162b2 mRNA COVID-19 vaccination. The diagnosis of Miller Fisher syndrome (MFS) was established based on physical examination, brain magnetic resonance imaging (MRI), cerebrospinal fluid analysis (CSF), and positron emission tomography (PET). There was no evidence of other predisposing infectious or autoimmune factors, and the period from COVID-19 vaccination to the appearance of neurological symptoms was similar to that of other vaccines and preceding events, such as infection.

Conclusion

Guillain–Barré syndrome (GBS) and its variants after COVID-19 vaccination are extremely rare. Note that more research is needed to establish an association between MFS and COVID-19 vaccines. In our opinion, the benefits of COVID-19 vaccination largely outweigh its risks.

Long-term MRI changes in a patient with Kelch-like protein 11-associated paraneoplastic neurological syndrome

BACKGROUND AND PURPOSE

The aim of this study was to identify the long-term radiological changes, autoantibody specificities, and clinical course in a patient with kelch-like protein 11 (KLHL11)-associated paraneoplastic neurological syndrome (PNS).

METHODS

Serial brain magnetic resonance images were retrospectively assessed. To test for KLHL11 autoantibodies, longitudinal cerebrospinal fluid (CSF) and serum samples were screened by Phage-display ImmunoPrecipitation and Sequencing (PhIP-Seq). Immunohistochemistry was also performed to assess for the presence of KLHL11 in the patient's seminoma tissue.

RESULTS

A 42-year-old man presented with progressive ataxia and sensorineural hearing loss. Metastatic seminoma was detected 11 months after the onset of the neurological symptoms. Although immunotherapy was partially effective, his cerebellar ataxia gradually worsened over the next 8 years. Brain magnetic resonance imaging revealed progressive brainstem and cerebellar atrophy with a "hot-cross-bun sign", and low-signal intensity on susceptibility-weighted imaging (SWI) in the substantia nigra, red nucleus and dentate nuclei. PhIP-Seq enriched for KLHL11-derived peptides in all samples. Immunohistochemical staining of mouse brain with the patient CSF showed co-localization with a KLHL11 commercial antibody in the medulla and dentate nucleus. Immunohistochemical analysis of seminoma tissue showed anti-KLHL11 antibody-positive particles in cytoplasm.

CONCLUSIONS

This study suggests that KLHL11-PNS should be included in the differential diagnosis for patients with brainstem and cerebellar atrophy and signal changes not only on T2-FLAIR but also on SWI, which might otherwise be interpreted as secondary to a neurodegenerative disease such as multiple system atrophy.

Brain magnetic resonance imaging and cognitive alterations after ablation in patients with atrial fibrillation

Catheter ablation is an important non-pharmacological intervention for atrial fibrillation (AF), but its effect on the incidence of asymptomatic cerebral emboli and long-term effects on cognitive function remain unknown. We prospectively enrolled 101 patients who underwent AF ablation. Brain magnetic resonance imaging (MRI) (72 patients) and neuropsychological assessments (66 patients) were performed 1–3 days (baseline) and 6 months after ablation. Immediately after ablation, diffusion-weighted MRI and 3-dimensional double inversion recovery (3D-DIR) detected embolic microinfarctions in 63 patients (87.5%) and 62 patients (86.1%), respectively. After 6 months, DIR lesions disappeared in 41 patients. Microbleeds (MBs) increased by 17%, and 65% of the de novo MBs were exactly at the same location as the microinfarctions. Average Mini-Mental State Examination scores improved from 27.9 ± 2.4 to 28.5 ± 1.7 (p = 0.037), and detailed neuropsychological assessment scores showed improvement in memory, constructional, and frontal lobe functions. Ejection fraction, left atrial volume index and brain natriuretic peptide level improved from baseline to 3–6 months after ablation. Despite incidental microemboli, cognitive function was preserved 6 months after ablation.

Cerebral Embolism Associated with Calcified Amorphous Tumor: A Review of Cerebral Infarction Cases

Calcified amorphous tumor (CAT) is a non-neoplastic tumor composed of calcified nodules consisting of amorphous fibrous material, and it may eventually cause cerebral infarction (CI). We experienced a 67-year-old woman with CAT who had recurrent CI. After excision of the CAT, the CI did not show recurrence. A review of previous papers on CI due to CAT in Pubmed revealed that 7 of 13 studies originated in Japan and that CI can occur even with small CAT. Surgical treatment is recommended to prevent CI recurrence, especially when CAT is accompanied by mitral annular calcification or has marked mobility.

Repurposing bromocriptine for Aβ metabolism in Alzheimer's disease (REBRAnD) study: randomised placebo-controlled double-blind comparative trial and open-label extension trial to investigate the safety and efficacy of bromocriptine in Alzheimer's disease with presenilin 1 (PSEN1) mutations

INTRODUCTION

Alzheimer's disease (AD) is one of the most common causes of dementia. Pathogenic variants in the presenilin 1 (PSEN1) gene are the most frequent cause of early-onset AD. Medications for patients with AD bearing PSEN1 mutation (PSEN1-AD) are limited to symptomatic therapies and no established radical treatments are available. Induced pluripotent stem cell (iPSC)-based drug repurposing identified bromocriptine as a therapeutic candidate for PSEN1-AD. In this study, we used an enrichment strategy with iPSCs to select the study population, and we will investigate the safety and efficacy of an orally administered dose of bromocriptine in patients with PSEN1-AD.

METHODS AND ANALYSIS

This is a multicentre, randomised, placebo-controlled trial. AD patients with PSEN1 mutations and a Mini Mental State Examination-Japanese score of ≤25 will be randomly assigned, at a 2:1 ratio, to the trial drug or placebo group (≥4 patients in TW-012R and ≥2 patients in placebo). This clinical trial consists of a screening period, double-blind phase (9 months) and extension phase (3 months). The double-blind phase for evaluating the efficacy and safety is composed of the low-dose maintenance period (10 mg/day), high-dose maintenance period (22.5 mg/day) and tapering period of the trial drug. Additionally, there is an open-labelled active drug extension period for evaluating long-term safety. Primary outcomes are safety and efficacy in cognitive and psychological function. Also, exploratory investigations for the efficacy of bromocriptine by neurological scores and biomarkers will be conducted.

ETHICS AND DISSEMINATION

The proposed trial is conducted according to the Declaration of Helsinki, and was approved by the Institutional Review Board (K070). The study results are expected to be disseminated at international or national conferences and published in international journals following the peer-review process.

TRIAL REGISTRATION NUMBER

jRCT2041200008, NCT04413344.

Neuromelanin-sensitive magnetic resonance imaging in disease differentiation for parkinsonism or neurodegenerative disease affecting the basal ganglia

INTRODUCTION

Several reports have shown that neuromelanin-sensitive magnetic resonance imaging (NMI) using 3T magnetic resonance imaging is useful for the differential diagnosis of Parkinson's disease (PD), progressive supranuclear palsy (PSP), and other neurological diseases. However, the number of cases in previous studies has been insufficient. We aimed to determine the relationship between NMI and severity of PD and related disorders, and thereby establish the diagnostic utility of NMI for diagnosing neurological diseases.

METHODS

We enrolled 591 patients (531 subjects after removal of duplicates) with parkinsonism who underwent NMI. The contrast ratio of the locus coeruleus (LC-CR) and the area of the substantia nigra pars compacta (SNc) were analyzed in each patient.

RESULTS

The patients' clinical diagnoses were as follows: 11 patients in the disease control group (DCG), 244 patients with PD, 49 patients with PSP, and 19 patients with multiple system atrophy with predominant parkinsonism. Additionally, some patients were diagnosed with dementia with Lewy bodies, vascular parkinsonism, and drug-induced parkinsonism. SNc in the patients with PD and PSP was significantly smaller than that in DCG. LC-CR in the patients with PD was lower than that in DCG; furthermore, LC-CR in the patients with PD was significantly lower than that in the patients with PSP. We found that an area under the receiver-operating characteristic curve, indicating diagnostic efficacy, of 0.85 for LC-CR is a promising biomarker for differentiating PD from PSP.

CONCLUSION

NMI effectively contributes to differentiating neurodegenerative diseases, such as PD and PSP.

Micro-MRI improves the accuracy of clinical diagnosis in cerebral small vessel disease

Even with postmortem pathological examination, only limited information is provided of the foci of in vivo clinical information. Cerebral small vessel disease, which is associated with ageing, dementia and stroke, highlights the difficulty in arriving at a definitive diagnosis of the lesions detected on in vivo radiological examination. We performed a radiological−pathological comparative study using ex vivo MRI to examine small cerebral lesions. Four patients with small vessel disease lesions detected on in vivo MRI were studied. Exact pathological findings of in vivo MRI-detected lesions were revealed. The ischaemic lesion after 17 days from onset showed positivity for peroxiredoxin, cluster of differentiation 204 and glial fibrillary acidic protein, indicating sterile inflammation and neuroprotective reaction. Cortical microinfarcts beneath the cortical superficial siderosis were associated with inflammation from the superficial layer in a patient with cerebral amyloid angiopathy; in this patient, a bilinear track-like appearance of the cortical superficial siderosis on the ex vivo MRI was compatible with iron deposition on the pia matter and within cortical layers II–III. An in vivo MRI-detected cerebral microbleed was revealed to be heterogeneous. An in vivo MRI-detected cerebral microbleed was revealed to be a venous angioma. Furthermore, a neuropathologically confirmed embolic cerebral microbleed was firstly detected using this method. Our results suggest that in vivo MRI-detected lobar cerebral microbleeds can be caused by non-cerebral amyloid angiopathy aetiologies, such as microembolism and venous angioma. Venous angioma and embolic microbleeds may mimic cerebral amyloid angiopathy markers on in vivo MRI. To clarify the clinical importance of these lesions, we should investigate their rate and frequency in a large cohort of healthy individuals and patients with cardiac risk factors. Thus, we provide evidence that ex vivo micro-MRI improves the clinical diagnosis of small vessel diseases.

Investigation of hypertensive arteriopathy-related and cerebral amyloid angiopathy-related small vessel disease scores in patients from a memory clinic: a prospective single-centre study

Objective

The severity of cerebral small vessel disease (SVD) is assessed through neuroimaging findings, including hypertensive arteriopathy (HA)-SVD and cerebral amyloid angiopathy (CAA)-SVD. HA-SVD and CAA-SVD have been collectively estimated as total scores: the HA-SVD and CAA-SVD scores, respectively. Previous reports suggest that HA-SVD scores are associated with cognitive function; however, the relationship between CAA-SVD scores and cognitive function remains unclear. Therefore, we examined the association between CAA-SVD scores and cognitive function. Furthermore, we developed a modified CAA-SVD score considering cortical microinfarcts and posterior dominant white matter hyperintensities, which are imaging findings of CAA, and examined the association between these scores and cognitive function in the same patient group.

Design

Prospective study.

Setting

Single centre study from a memory clinic.

Participants

Subjects were diagnosed with mild cognitive impairment (MCI) or mild dementia in our memory clinic between February 2017 and July 2019 and underwent clinical dementia rating scale and brain MRI assessment. A total of 42 patients (aged 75.3±9.12 years) were registered prospectively.

Primary and secondary outcome measures

We evaluated intellectual function, memory, frontal lobe function and constructional ability. Furthermore, the relationship between each score and cognitive function was examined.

Results

The CAA-SVD score showed significant associations with cognitive function (R²=0.63, p=0.016), but the HA-SVD score did not (R²=0.41, p=0.35). The modified CAA-SVD score was also significantly associated with cognitive function (R²=0.65, p=0.008).

Conclusion

Cognitive function is associated with the CAA-SVD score, and more efficiently with the modified CAA-SVD score, in memory clinic patients. Although we have not validated the weighting of the modified CAA-SVD score, these scores can be a predictor of cognitive deterioration in patients with MCI and mild dementia.

Biphasic roles of pentraxin 3 in cerebrovascular function after white matter stroke

Recent clinical studies suggest that pentraxin 3 (PTX3), which is known as an acute-phase protein that is produced rapidly at local sites of inflammation, may be a new biomarker of disease risk for central nervous system disorders, including stroke. However, the effects of PTX3 on cerebrovascular function in the neurovascular unit (NVU) after stroke are mostly unknown, and the basic research regarding the roles of PTX3 in NVU function is still limited. In this reverse translational study, we prepared mouse models of white matter stroke by vasoconstrictor (ET-1 or L-Nio) injection into the corpus callosum region to examine the roles of PTX3 in the pathology of cerebral white matter stroke. PTX3 expression was upregulated in GFAP-positive astrocytes around the affected region in white matter for at least 21 days after vasoconstrictor injection. When PTX3 expression was reduced by PTX3 siRNA, blood-brain barrier (BBB) damage at day 3 after white matter stroke was exacerbated. In contrast, when PTX3 siRNA was administered at day 7 after white matter stroke, compensatory angiogenesis at day 21 was promoted. In vitro cell culture experiments confirmed the inhibitory effect of PTX3 in angiogenesis, that is, recombinant PTX3 suppressed the tube formation of cultured endothelial cells in a Matrigel-based in vitro angiogenesis assay. Taken together, our findings may support a novel concept that astrocyte-derived PTX3 plays biphasic roles in cerebrovascular function after white matter stroke; additionally, it may also provide a proof-of-concept that PTX3 could be a therapeutic target for white matter-related diseases, including stroke.

Association between cortical microinfarcts and total small vessel disease burden in cerebral amyloid angiopathy on 3-Tesla magnetic resonance imaging

BACKGROUND AND PURPOSE

Cortical microinfarcts (CMIs) are frequently found in the brains of patients with advanced cerebral amyloid angiopathy (CAA) at autopsy. The small vessel disease (SVD) score for CAA (i.e., the CAA-SVD score) has been proposed to evaluate the severity of CAA-associated vasculopathic changes by a combination of magnetic resonance imaging (MRI) markers. The aim of this study was to examine the association between total CAA-SVD score and features of CMIs on in vivo 3-Tesla MRI.

METHODS

Eighty patients with probable CAA were retrospectively analyzed. Lobar cerebral microbleeds, cortical superficial siderosis, enlargement of perivascular space in the centrum semiovale and white matter hyperintensity were collectively assessed, and the total CAA-SVD score was calculated. The presence of CMI was also examined.

RESULTS

Of the 80 patients, 13 (16.25%) had CMIs. CMIs were detected more frequently in the parietal and occipital lobes. A positive correlation was found between total CAA-SVD score and prevalence of CMI (ρ = 0.943; p = 0.005). Total CAA-SVD score was significantly higher in patients with CMIs than in those without (p = 0.009). In a multivariable logistic regression analysis, the presence of CMIs was significantly associated with total CAA-SVD score (odds ratio 2.318 [95% confidence interval 1.228-4.376]; p = 0.01, per each additional point).

CONCLUSIONS

The presence of CMIs with a high CAA-SVD score could be an indicator of more severe amyloid-associated vasculopathic changes in patients with probable CAA.

Effect of air pollution on acute heart failure hospitalization differ across specific heart failure populations

Introduction

Several report showed the association between ambient air pollution including particular matter under 2.5um (PM2.5) and increasing rate of hospitalization for heart failure. However, these report analyzed mainly cross-sectional, epidemiological data, thus the reports regarding association between vulnerability to PM2.5 and specific populations in acute heart failure (AHF) were scarce.

Purpose

1. To analyze the association between air pollution and rate of hospitalization for AHF

2. To analyze whether the vulnerability to air pollution differ between specific populations in AHF. Methods

A case-cross over analysis was conducted to 4980 consecutive patients registered for multicenter acute heart failure registry in 2017 in our city Japan. This registry enrolled patients transferred to cardiovascular care unit (80 institutions) via emergency medical services across our city area. Logistic regression analysis were conducted to estimate percentage changes in the rate of acute heart failure hospitalization associated with per 1μg/m3 PM2.5 concentration increase. We also conducted subgroup analysis for patients stratified by age, gender, comorbidities, left ventricular ejection fraction, and clinical scenario.

Results

An increase in 1 μg/m3 PM2.5 concentration corresponded to 2.9% (95% CI 1.2–4.6%) increase in AHF hospitalization. Patients with age younger than 75, without prior heart failure hospitalization, without history of hypertension, without anemia, and with reduced ejection fraction were more susceptible to increase in PM2.5 concentration (Figure).

Conclusions

Increase in PM2.5 concentration was associated with increased rate of AHF hospitalization. Effect of PM2.5 may differ across specific AHF subpopulations.

Figure 1

Funding Acknowledgement

Type of funding source: Other. Main funding source(s): Tokyo Metropolitan Government

A Nationwide Survey and Multicenter Registry-Based Database of Cerebral Autosomal Dominant Arteriopathy With Subcortical Infarcts and Leukoencephalopathy in Japan

Objectives

Clinical characteristics of cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) include migraine, recurrent stroke, white matter lesions, and vascular dementia. CADASIL is one of the most common hereditary cerebral small vessel diseases. Clinical presentation of CADASIL varies and a racial gap may exist between the Asian and Caucasian populations. This is the first nationwide epidemiological survey which aimed to elucidate the clinical features of CADASIL in Japan. Moreover, the registration database of CADASIL was constructed.

Methods

Subjects included CADASIL patients who visited the hospitals (totally 1,448 hospitals) certified by the Japanese Society of Neurology and/or Japan Stroke Society in 2016. This study consisted of a two-step survey; patients with CADASIL were identified genetically by the first questionnaire, and their clinical features were assessed by the second questionnaire. Selected 6 hospitals registered the data of all CADASIL patients using a Research Electronic Data Capture (REDCap) system for the second questionnaire.

Results

Based on the criteria, 88 patients (50 male and 38 female) with CADASIL were enrolled. The mean age of symptom onset was 49.5 years. Sixteen (18.2%) patients had an elderly onset (>60 years). Thirteen patients (13.6%) had history of migraine with aura and 33 patients (37.5%) had vascular risk factor(s). From among the 86 patients who were examined using magnetic resonance imaging, abnormal deep white matter lesions were detected in 85 patients (98.8%), WMLs extending to anterior temporal pole in 73 patients (84.9%), and cerebral microbleeds in 41 patients (47.7%). Anti-platelet therapy was received by 65 patients (73.9%). Thirty-eight patients (43.2%) underwent treatment with lomerizine hydrochloride. Thirty-four different mutations of NOTCH3 were found in exons 2, 3, 4, 5, 6, 8, 11, 14, and 19. Most of the mutations existed in exon 4 (n = 44, 60.3%). The prevalence rate of CADASIL was 1.20 to 3.58 per 100,000 adults in Japan.

Conclusion

This questionnaire-based study revealed clinical features and treatment status in Japanese CADASIL patient, although it may not be an exhaustive search. We have constructed the REDCap database for these CADASIL patients.

HTRA1-Related Cerebral Small Vessel Disease: A Review of the Literature

Cerebral autosomal recessive arteriopathy with subcortical infarcts and leukoencephalopathy (CARASIL) is clinically characterized by early-onset dementia, stroke, spondylosis deformans, and alopecia. In CARASIL cases, brain magnetic resonance imaging reveals severe white matter hyperintensities (WMHs), lacunar infarctions, and microbleeds. CARASIL is caused by a homozygous mutation in high-temperature requirement A serine peptidase 1 (HTRA1). Recently, it was reported that several heterozygous mutations in HTRA1 also cause cerebral small vessel disease (CSVD). Although patients with heterozygous HTRA1-related CSVD (symptomatic carriers) are reported to have a milder form of CARASIL, little is known about the clinical and genetic differences between the two diseases. Given this gap in the literature, we collected clinical information on HTRA1-related CSVD from a review of the literature to help clarify the differences between symptomatic carriers and CARASIL and the features of both diseases. Forty-six symptomatic carriers and 28 patients with CARASIL were investigated. Twenty-eight mutations in symptomatic carriers and 22 mutations in CARASIL were identified. Missense mutations in symptomatic carriers are more frequently identified in the linker or loop 3 (L3)/loop D (LD) domains, which are critical sites in activating protease activity. The ages at onset of neurological symptoms/signs were significantly higher in symptomatic carriers than in CARASIL, and the frequency of characteristic extraneurological findings and confluent WMHs were significantly higher in CARASIL than in symptomatic carriers. As previously reported, heterozygous HTRA1-related CSVD has a milder clinical presentation of CARASIL. It seems that haploinsufficiency can cause CSVD among symptomatic carriers according to the several patients with heterozygous nonsense/frameshift mutations. However, the differing locations of mutations found in the two diseases indicate that distinct molecular mechanisms influence the development of CSVD in patients with HTRA1-related CSVD. These findings further support continued careful examination of the pathogenicity of mutations located outside the linker or LD/L3 domain in symptomatic carriers.

Myasthenia gravis with anti-muscle-specific tyrosine kinase antibodies during therapy for multiple myeloma: a case report

BACKGROUND

The onset of myasthenia (MG) gravis with anti-muscle-specific tyrosine kinase (MuSK) antibodies most commonly peaks in the fourth decade of life, and MG with MuSK antibodies (MuSK-MG) rarely coexists with a malignant tumor. To date, MuSK-MG has not been reported in multiple myeloma (MM).

CASE PRESENTATION

A 60-year-old male with MM who was receiving treatment with bortezomib and thalidomide presented diplopia, ptosis, and limb weakness. A diagnosis of MM with Bence-Jones proteinuria was established when he was 56 years old, and he received chemotherapy with four courses of bortezomib and dexamethasone. Although he received thalidomide as maintenance therapy, it was discontinued a year before hospital admission because of sensory neuropathy as a side effect. Six months before hospital admission, he developed mild diplopia. One month before admission, his chemotherapy was interrupted because of viral infection and fatigability. Then he developed neck weakness and bilateral ptosis. A diagnosis of MuSK-MG was made based on neurological and serological examinations. According to the previous relevant literature, this is the first report of MuSK-MG in a patient with MM.

CONCLUSIONS

In patients with MM, the possibility of co-existing of autoimmune disease, including MuSK-MG, should be considered. This case emphasizes the need to still consider testing for anti-MuSK antibodies in older MM patients where there is clinical suspicion for possible MG despite negative anti-acetylcholine receptor antibodies and lacking classic MuSK MG phenotype at onset.

Clinical Features and Experimental Models of Cerebral Small Vessel Disease

Cerebral small vessel disease (SVD) refers to a group of disease conditions affecting the cerebral small vessels, which include the small arteries, arterioles, capillaries, and postcapillary venules in the brain. SVD is the primary cause of vascular cognitive impairment and gait disturbances in aged people. There are several types of SVD, though arteriolosclerosis, which is mainly associated with hypertension, aging, and diabetes mellitus, and cerebral amyloid angiopathy (CAA) comprise most SVD cases. The pathology of arteriolosclerosis-induced SVD is characterized by fibrinoid necrosis and lipohyalinosis, while CAA-associated SVD is characterized by progressive deposition of amyloid beta (Aβ) protein in the cerebral vessels. Brain magnetic resonance imaging (MRI) has been used for examination of SVD lesions; typical lesions are characterized by white matter hyperintensity, lacunar infarcts, enlargement of perivascular spaces (EPVS), microbleeds, cortical superficial siderosis (cSS), and cortical microinfarcts. The microvascular changes that occur in the small vessels are difficult to identify clearly; however, these consequent image findings can represent the SVD. There are two main strategies for prevention and treatment of SVD, i.e., pharmacotherapy and lifestyle modification. In this review, we discuss clinical features of SVD, experimental models replicating SVD, and treatments to further understand the pathological and clinical features of SVD.

Cortical Microinfarcts Detected by 3-Tesla Magnetic Resonance Imaging

Background and Purpose—

Cortical microinfarcts (CMIs) are small ischemic lesions found in cerebral amyloid angiopathy (CAA) and embolic stroke. This study aimed to differentiate CMIs caused by CAA from those caused by microembolisms, using 3-Tesla magnetic resonance imaging.

Methods—

We retrospectively investigated 70 patients with at least 1 cortical infarct <10 mm on 3-dimensional double inversion recovery imaging. Of the 70 patients, 43 had an embolic stroke history (Emboli-G) while 27 had CAA-group. We compared the size, number, location, and distribution of CMIs between groups and designed a radiological score for differentiation based on the comparisons.

Results—

CAA-group showed significantly more lesions <5 mm, which were restricted to the cortex ( P <0.01). Cortical lesion number was significantly higher in Emboli-G than in CAA-group (4 versus 2; P <0.01). Lesions in CAA-group and Emboli-G were disproportionately located in the occipital lobe ( P <0.01) and frontal or parietal lobe ( P =0.04), respectively. In radiological scoring, ≥3 points strongly predicted microembolism (sensitivity, 63%; specificity, 92%) or CAA (sensitivity, 63%; specificity, 91%). The areas under the receiver operating characteristic curve were 0.85 and 0.87 for microembolism and CAA, respectively.

Conclusions—

Characteristics of CMIs on 3T-magnetic resonance imaging may differentiate CMIs due to CAA from those due to microembolisms.

Abstract TP229: Cerebral Venous Thrombosis Caused by Congenital Thrombophilia in Japan

Background: Cerebral venous thrombosis is an uncommon type of stroke that sometimes affects young to middle-aged patients. Various conditions can cause CVT, including drugs, infection, dehydration, pregnancy, malignancies, and acquired and congenital thrombophilia. Hereditary thrombophilia caused by genetic mutation, such as antithrombin, protein C (PC) and protein S (PS), requires warning about the risk and signs of thrombosis recurring. Because CVT itself is a rare disease, it’s sometimes difficult to diagnosis the hereditary thrombophilia in each case. This study describes the clinical features and causes related to CVT in Japan, and elucidates the characteristics of CVT caused by hereditary thrombophilia.

Methods: We enrolled 40 patients (24 males, 16 females, age: 18-81 years) diagnosed CVT confirmed by either magnetic resonance venography, enhanced computed tomography, or angiography. Demographic data and clinical features were recorded and compared.

Results: Eleven patients (6 males, 5 females, age: 27-71 years) were diagnosed CVT due to congenital thrombophilia, and the other twenty-nine patients (18 males, 11 females, age: 18-81 years) were not. Congenital thrombophilia included five patients with PS gene mutation, three with PC gene mutation, two with antithrombin gene mutation, and one alpha fibrinogen gene mutation. Although we failed to detect a significant statistical difference between congenital thrombophilia patients and others with regards to age, sex, symptoms, vein of occlusion, d-dimer levels, activity levels of PS and PC were significantly decreased in congenital thrombophilia patients.

Discussion: Cerebral venous thrombosis in Japanese patients is frequently associated PS or PC gene mutations. This study showed CVT caused by congenital thrombophilia had low activity of PS and PC. Clinicians should aware the presence of PS or PC gene mutations during the treatment of CVT and check the PS and PC activity.

Abstract TP213: Diagnostic Score to Differentiate the Etiology of Cortical Microinfarcts on 3-Tesla MRI

Background and Purpose: Cortical microinfarcts (CMIs) are small ischemic lesions found in cerebral amyloid angiopathy (CAA) patients, which are also associated with embolic stroke. This study aimed to differentiate cortical microinfarcts caused by CAA from those caused by microembolism, using 3-tesla magnetic resonance imaging.

Methods: We retrospectively investigated 119 patients with at least 1 cortical infarct <10 mm on 3D double inversion recovery imaging. Forty-three patients with an embolic stroke history were included as the emboli group (Emboli-G) and 27 patients with CAA were included as the CAA group (CAA-G), based on the modified Boston criteria. We compared the size, number, location, and distribution of CMIs between groups to assess CMI etiology. Using this information, we designed a radiological diagnostic score, which incorporated data on the location, size, distribution, and numbers of CMIs.

Results: CAA-G patients showed significantly more lesions <5 mm, which were restricted to the cortex (p<0.01). Cortical lesion number was significantly higher in Emboli-G than in CAA-G patients (4 vs 2; p<0.01). The diameter of cortical lesions was significantly larger in Emboli-G than in CAA-G patients (3.8 mm vs 3.0 mm; p<0.01). Lesions in CAA-G and Emboli-G patients were disproportionately located in the occipital lobe (p<0.01) and frontal or parietal lobe (p=0.04), respectively. In diagnostic scoring, a score of ≥3 points strongly predicted microembolism (sensitivity, 63%; specificity, 92%) or CAA (sensitivity, 63%; specificity, 91%). The area under the curve was 0.85 and 0.87 for microembolism and CAA, respectively.

Conclusions: Our radiological diagnostic score may be a powerful tool for differentiating the etiology of CMIs.

Symptomatic Characteristics of Parkinson's Disease Induced by Neuroleptic Drugs, Based on a Functional Neuroimaging Diagnosis

Objective When patients take neuroleptics, the distinction between Parkinson's disease (PD) and drug-induced parkinsonism (DIP) based solely on clinical features can become difficult. At present, ¹²³I-FP-CIT SPECT (DAT-SPECT) and ¹²³I-metaiodobenzylguanidine (MIBG) myocardial scintigraphy are widely used to supplement the differential diagnosis of parkinsonism. This study assessed the clinical symptoms and neurological findings in the patients suspected of having DIP based on DAT-SPECT findings. Methods Twenty-three patients (11 men, 12 women, age: 52-81 years old) presenting with DIP were recruited. All patients underwent neurological examinations, including brain magnetic resonance imaging and DAT-SPECT. Patients who showed abnormal DAT-SPECT results underwent MIBG myocardial scintigraphy. Results Eleven patients showed a reduction in the ligand uptake on DAT-SPECT (DAT-positive group), and nine of these patients showed a low delayed heart-to-mediastinum (H/M) ratio on MIBG myocardial scintigraphy. The remaining 12 patients showed normal results on DAT-SPECT (DAT-negative group). All patients in the DAT-positive group had asymmetric motor symptoms, whereas only 4 in the DAT-negative group exhibited this clinical feature (p=0.001). A detailed medical history showed that 7 of the 11 patients in the DAT-positive group had prodromal symptoms for PD. However, only 1 patient in the DAT-negative group exhibited these symptoms (p= 0.009). Although two patients in the DAT-negative group showed poor improvement, they showed a normal H/M ratio on MIBG and no response to levodopa. Conclusion The patients in the DAT-positive group might have prodromal symptoms that were worsened by neuroleptic drugs. The results of detailed history-taking and neurological findings seem to indicate cases of compromised dopaminergic transmission before the administration of neuroleptic drugs.

Hypertensive Arteriopathy and Cerebral Amyloid Angiopathy in Patients with Cognitive Decline and Mixed Cerebral Microbleeds

BACKGROUND

Hypertensive arteriopathy (HA) and cerebral amyloid angiopathy (CAA) may contribute to the development of mixed cerebral microbleeds (CMBs). Recently, the total small vessel disease (SVD) scores for HA and CAA were proposed, which are determined by a combination of MRI markers to reflect overall severity of these microangiopathies.

OBJECTIVE

We investigated whether or not total HA-SVD and CAA-SVD scores could be used to predict overlap of HA and CAA in patients with mixed CMBs.

METHODS

Fifty-three subjects with mixed CMBs were retrospectively analyzed. MRI markers (CMBs, lacunes, perivascular space, white matter hyperintensity [WMH] and cortical superficial siderosis [cSS]) were assessed. The HA-SVD score and CAA-SVD score were obtained for each subject. Anterior or posterior WMH was also assessed using the age-related white matter changes scale.

RESULTS

The two scores were positively correlated (ρ= 0.449, p < 0.001). The prevalence of lobar dominant CMB distribution (p < 0.001) and lacunes in the centrum semiovale (p < 0.001) and the severity of WMH in the parieto-occipital lobes (p = 0.004) were significantly higher in the high CAA-SVD score group. cSS was found in four patients with high CAA-SVD score who showed lobar-dominant CMB distribution and severe posterior WMH.

CONCLUSION

Mixed CMBs are mainly due to HA. Assessing both two scores may predict the overlap of HA and CAA in individuals with mixed CMBs. Patients with a high CAA-SVD score may have some degree of advanced CAA, especially when lobar predominant CMBs, severe posterior WMH, lobar lacunes, or cSS are observed.

Reversible splenial lesion in a patient with new-onset refractory status epilepticus (NORSE)

New-onset refractory status epilepticus (NORSE) is a rare neurological emergency condition with poor prognosis. A 30-year-old male suddenly had tonic-clonic convulsions seven days after a preceding fever and diarrhea. MRI showed a reversible splenial lesion, and he developed refractory multifocal and generalized seizures in spite of anticonvulsant medication. He was diagnosed with NORSE and received a combination treatment with immunotherapy and targeted temperature management (TTM), which effectively decreased his seizures. This case suggests that even for patients with reversible splenial lesions, NORSE should be considered, and that treatment with immunotherapy and TTM may be effective.

•

New-onset refractory status epilepticus (NORSE) can present with a reversible splenial lesion.

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Targeted temperature management and immunotherapy are useful for the treatment of a patient with NORSE who has a high fever.

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Arterial spin labeling on MRI showed increased blood flow, assumed to be due to the persistent seizure activity.

MEFV gene mutations in neuro-Behçet's disease and neuro-Sweet disease

Mediterranean fever (MEFV) gene mutations are associated with familial Mediterranean fever (FMF). Recent studies have suggested that MEFV gene mutations may act as disease modifiers in neuro‐Behçet's (NBD) disease and neuro‐Sweet disease (NSD). We investigated MEFV genes and clinical features in 17 patients with NBD or NSD. MEFV gene mutations were frequently observed (70.6%). Headaches and exertional leg pain were associated with MEFV gene mutations (P < 0.05). Moreover, higher frequency of white matter lesions without sites predilection (P < 0.05) and non‐parenchymal lesions (P < 0.05) were also observed. MEFV gene mutations may be associated with particular findings and lesion sites.

Invasive Salmonella Enteritidis infection complicated by bacterial meningitis and vertebral osteomyelitis shortly after influenza A infection in an immunocompetent young adult

Non-typhoidal Salmonella usually manifests as a self-limited acute gastroenteritis but may also cause severe invasive infections almost exclusively among children or immunosuppressed patients. A previously healthy 22-year-old man developed high fever with coma, multiple organ failure and shock. He had visited another hospital complaining of fever 2 days previously and was diagnosed with a common cold. No obvious site of infection was identified by radiology and a rapid test for influenza A virus was positive, indicating possible influenza-associated encephalopathy. However, blood as well as CSF culture yielded Salmonella enterica serotype Enteritidis. Therefore, the patient was considered to be suffering from bacterial meningitis with septic shock concomitant with influenza infection. Antiviral drugs and therapy for septic shock were initiated. He stabilized relatively quickly and his mental status dramatically improved. The patient denied preceding gastrointestinal symptoms, but mentioned that he received positive fecal Salmonella species culture results without medical intervention about 3 months previously. His laboratory values showed marked improvement but his elevated inflammatory markers and fever were sustained. On the 17th day of hospitalization, he complained of back pain and MRI showed lumbar vertebral osteomyelitis. This case indicates that (i) invasive Salmonella infection can be developed even in previously healthy adults; (ii) chronic carriage of Salmonella is a predisposing factor to development of invasive infections, and influenza infection may contribute to such "breakthrough infections"; (iii) attention to manifestation of metastatic extra-intestinal foci even after resolution of sepsis is necessary.

Microbleeds after Carotid Artery Stenting: Small Embolism May Induce Cerebral Microbleeds

Background

Since the advent of magnetic resonance imaging technology, cerebral microbleeds can be diagnosed in vivo. However, the underlying mechanism of cerebral microbleed formation is not fully understood.

Objectives

This study aimed to identify the factors associated with cerebral microbleeds after carotid artery stenting (CAS).

Method

We retrospectively examined 125 patients who underwent CAS for carotid stenosis. Cerebral microbleeds were investigated using T2*-weighted gradient-echo (GRE) imaging before and after CAS. We analyzed the possible association of new microbleeds with the following risk factors: the number of baseline microbleeds and ischemic cerebral lesions, the occurrence of cerebral hyperperfusion syndrome, and new ischemic cerebral lesions after CAS.

Results

Baseline cerebral microbleeds were detected in 53 patients (42.4%). New cerebral microbleeds after CAS were observed in 13 of 125 patients (10.4%) and were exclusively associated with new ischemic lesions but not with other risk factors. No patient showed a merged image of a new cerebral microbleed on GRE imaging or a new ischemic lesion on diffusion-weighted imaging. Lobar and deep microbleeds were noted in 12/13 (92.3%) and 1 patient (7.7%), respectively. Of 12 patients with new microbleeds, 10 (76.9%) and 2 (15.4%) had a new microbleed in the ipsilateral and contralateral hemispheres, respectively.

Conclusions

We found that new cerebral microbleeds developed after CAS and that these might be associated with new ischemic lesions, mostly in the territory of the treated carotid artery. We speculate that these microbleeds result from the deoxygenation of hemoglobin in the embolus or, alternatively, small hemorrhagic transformation of ischemic lesions.

Vertebral artery dissection associated with familial Mediterranean fever and Behçet's disease

Vertebral artery dissection and recurrent meningitis are rare complications in Behçet's disease. Behçet's disease may be associated with familial Mediterranean fever. Here, we describe a 52‐year‐old woman with severe headache who exhibited recurrent meningitis and vertebral artery dissection. Cerebrospinal fluid showed high levels of interleukin‐6. Magnetic resonance imaging revealed right vertebral artery dissection. The patient had three heterozygous mutations in the familial Mediterranean fever gene (MEFV) gene. She fulfilled criteria for diagnosis of Behçet's disease and familial Mediterranean fever. In conclusion, mutations of the MEFV gene may cause neuro‐inflammatory disorders and cerebrovascular disorders by reducing anti‐inflammatory activity of pyrin.

Differential roles of epigenetic regulators in the survival and differentiation of oligodendrocyte precursor cells

During development or after brain injury, oligodendrocyte precursor cells (OPCs) differentiate into oligodendrocytes to supplement the number of oligodendrocytes. Although mechanisms of OPC differentiation have been extensively examined, the role of epigenetic regulators, such as histone deacetylases (HDACs) and DNA methyltransferase enzymes (DNMTs), in this process is still mostly unknown. Here, we report the differential roles of epigenetic regulators in OPC differentiation. We prepared primary OPC cultures from neonatal rat cortex. Our cultured OPCs expressed substantial amounts of mRNA for HDAC1, HDAC2, DNMT1, and DNMT3a. mRNA levels of HDAC1 and HDAC2 were both decreased by the time OPCs differentiated into myelin-basic-protein expressing oligodendrocytes. However, DNMT1 or DNMT3a mRNA level gradually decreased or increased during the differentiation step, respectively. We then knocked down those regulators in cultured OPCs with siRNA technique before starting OPC differentiation. While HDAC1 knockdown suppressed OPC differentiation, HDAC2 knockdown promoted OPC differentiation. DNMT1 knockdown also suppressed OPC differentiation, but unlike HDAC1/2, DNMT1-deficient cells showed cell damage during the later phase of OPC differentiation. On the other hand, when OPCs were transfected with siRNA for DNMT3a, the number of OPCs was decreased, indicating that DNMT3a may participate in OPC survival/proliferation. Taken together, these data demonstrate that each epigenetic regulator has different phase-specific roles in OPC survival and differentiation.