White matter changes in 80 mild cognitive impairment patients using magnetic resonance imaging

BACKGROUND： Many studies have suggested that one possible etiology of mild cognitive impairment is small vessel cerebrovascular disease, which is associated with small subcortical infarcts and white matter abnormalities. These white matter changes have been detected as white matter hyperintensity （WMH） using magnetic resonance imaging. WMH may be associated with frontal lobe dysfunction. OBJECTIVE： To examine white matter changes in mild cognitive impairment patients of different subtypes, and to evaluate the correlation between white matter changes and neuropsychological characteristics, demographic information, vascular risk factors, and mild cognitive impairment subtypes. DESIGN, TIME AND SETTING： The neurophysiological, comparison study was performed at the Department of Neurology Memory Clinic, Ulsan University Hospital, South Korea, between March 2007 and March 2008. PARTICIPANTS： Out of a total of 83 subjects with clinically diagnosed mild cognitive impairment at the out-patient clinic, 3 subjects with severe WMH were excluded. A total of 80 subjects were included in this study. No patients suffered from cognitive impairment induced by neurological diseases, mental disorders, or somatic diseases. In accordance with magnetic resonance imaging results, the patients were assigned to two subtypes： 56 subjects without WMH and 24 subjects with WMH. METHODS： All patients were subjected to a standard neuropsychological battery using the Korean version of the Mini-Mental State Examination, Clinical Dementia Rating, and comprehensive Seoul Neuropsychological Screening Battery. The Clinical Dementia Rating reflected general cognitive function of patients. Results from the Seoul Neuropsychological Screening Battery reflected attention, language function, visuospatial function, verbal memory, nonverbal memory, long-term memory, and frontal/executive function. Magnetic resonance imaging was used to map changes in the brain. MAIN OUTCOME MEASURES： The association between various white matter changes and neuropsychological characteristics, demographic information, vascular risk factors, and mild cognitive impairment subtypes was measured, based primarily on neuropsychological profiles using statistical methods. RESULTS： WMH was significantly associated with neuropsychological characteristics in MCI patients （P 〈 0.05 or P 〈 0.01）, in particular with frontal/executive dysfunction. WMH was significantly correlated with age （P = 0.022） and vascular risk factors （P = 0.006）, independent of gender and MCI subtypes. CONCLUSION： WMH was significantly associated with frontal/executive dysfunction in mild cognitive impairment.

Association between scrub typhus encephalitis and diffusion tensor tractography detection of Papez circuit injury:A case report

BACKGROUND It is difficult to restore the cognitive functions of patients with impaired cognition caused by brain injury.Diffusion tensor imaging can visualize the integrity of neural tracts in the white matter(WM)three-dimensionally.It is unclear whether encephalitis following scrub typhus damages the WM.For the first time,we aimed to report diffusion tensor tractography(DTT)findings in a chronic patient with cognitive impairment following scrub typhus encephalitis,which revealed injury to the Papez circuit of the WM.CASE SUMMARY A 70-year-old male patient was affected by encephalitis caused by scrub typhus that occurred 23 years ago.He had poor cognition and his clinical examination findings were as follows:Mini-Mental Status Examination score,14;and handgrip strength(right/left,kg),32.3/31.3.DTT revealed serious injuries of the left thalamocingulate tract and right mammillothalamic tract in the Papez circuit,and a partial injury of the anterior part of the fornix.CONCLUSION Using DTT,we found a relationship between cognitive impairment and the integrity of the Papez circuit following scrub typhus.

Comparative effectiveness of combined antiplatelet treatments in acute minor ischaemic stroke

Background No study has thoroughly compared the effectiveness of combined antiplatelet treatments(other than clopidogrel–aspirin)versus clopidogrel–aspirin or aspirin alone for early secondary prevention in acute ischaemic stroke.Methods We identified patients with acute,minor,non-cardiogenic ischaemic stroke treated with aspirin alone,clopidogrel–aspirin or other combination treatment.Propensity scores considering the inverse probability of treatment weighting were used to adjust for baseline imbalances.The primary outcome was the composite of all strokes(ischaemic or haemorrhagic),myocardial infarction and all-cause mortality at 3 months.Results Among 12234 patients(male:61.9%;age:65.5±13 years)who met the eligibility criteria,aspirin,clopidogrel–aspirin and other combination treatments were administered in 52.2%,42.9%and 4.9%of patients,respectively.In the crude analysis,the primary outcome event at 3 months occurred in 14.5%of the other combination group,14.4%of the aspirin group and 13.0%of the clopidogrel–aspirin group.In the weighted Cox proportional hazards analysis,the 3-month primary outcome event occurred less frequently in the clopidogrel–aspirin group than in the other combination group(weighted HR:0.82(0.59–1.13)),while no association was found between the aspirin group(weighted HR:1.04(0.76–1.44))or other combination group and the 3-month primary outcome.Conclusion Other combined antiplatelet treatment,compared with aspirin alone or clopidogrel–aspirin,was not associated with reduced risks of primary composite vascular events or recurrent stroke during the first 3 months after stroke.Therefore,the results suggest that other combination treatments,particularly the cilostazol-based combination,may not be effective alternatives for clopidogrel–aspirin to prevent early vascular events in patients with acute minor stroke.Further exploration in clinical trials will be needed.