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N Hirono

Publications and source records attributed to N Hirono.

At least 19 recordsLinked to original sources
PubMed2003

Striatal infarcts mimicking frontotemporal dementia: a case report.

We described a patient with bilateral striatal infarcts, in whom stereotyped and disinhibited behaviors were insidiously emerged over 2 years mimicking frontotemporal dementia (FTD). A positron emission tomography with 18-fluorodeoxy glucose showed a hypometabolism in the frontal lobes, basal ganglia, and thalami. The peculiar behavioral alterations remained unchanged for the following 7 years, suggesting that the disease is not degenerative but of vascular origin. A disruption of the fronto-subcortical circuits at the level of the striatum or the anterior thalamic peduncle is attributable to the FTD-like behavioral and cognitive syndrome.

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PubMed2002

The effect of APOE epsilon4 allele on cerebral glucose metabolism in AD is a function of age at onset.

BACKGROUND: Although the APOE epsilon4 allele is a well-known risk factor for developing AD, the impact of the epsilon4 allele on clinical manifestations in patients with AD is still controversial. One possible reason for this controversy is that previous studies did not consider the effect of patient age at symptom onset. OBJECTIVE: To investigate the possible impact of patient age at onset of AD on the effect of APOE genotype on regional cerebral glucose metabolism (rCMRglc). METHODS: The authors compared rCMRglc between probable AD patients (based on criteria of the National Institute of Neurologic Disease and Stroke/AD and Related Disorders Association) with APOE epsilon4/4 and APOE epsilon3/3 alleles in early-onset (< or =65 years old) and late-onset (>65 years old) groups. In each group, the patients with APOE epsilon4/4 and APOE epsilon3/3 alleles were comparable for age at onset, age at examination, sex, disease duration, education level, and severity of dementia. RESULTS: In the early-onset group, the patients with the APOE epsilon4/4 genotype showed a significant decrease of rCMRglc in the medial temporal lobe and a significant increase of rCMRglc in the inferior parietal and posterior temporal cortices as compared with those patients with the APOE epsilon3/3 genotype. In the late-onset group, there were no significant differences in the rCMRglc pattern between the patients with APOE epsilon4/4 and APOE epsilon3/3 alleles. CONCLUSIONS: The current findings indicate that the impact of the APOE epsilon4 genotype on cerebral glucose metabolism of patients with AD may be a function of age at symptom onset.

Age of Onset↗
PubMed2001

Apolipoprotein E epsilon 4 and the pattern of regional brain atrophy in Alzheimer's disease.

BACKGROUND: Although the APOE epsilon 4 allele increases the risk of developing AD, the effects of the epsilon 4 allele on brain atrophy in clinical AD patients are controversial. OBJECTIVE: To investigate a possible relationship between the genetic variants of APOE and brain atrophy in patients with AD. METHODS: Using MRI-based volumetry techniques, the authors compared the volumes of the hippocampal formation, amygdaloid complex, and whole brain in probable AD patients (based on criteria of the National Institute for Neurological and Communicative Disorders and Stroke/Alzheimer's Disease and Related Disorders Association) with different APOE alleles. One group (n = 46) had the epsilon 3/3 allele, one group (n = 46) had the epsilon 3/4 allele, and one group (n = 46) had the epsilon 4/4 allele. The three groups were matched for age, sex, disease duration, education level, and severity of dementia represented by their score of the Mini-Mental State Examination. A possible difference in pattern of cognitive deficits with dose of the APOE epsilon 4 allele was also examined. RESULTS: The normalized hippocampal volume was correlated with the number of APOE epsilon 4 alleles (r = -0.285, p = 0.0007). The amygdalar volume was also correlated with the number of APOE epsilon 4 alleles (r = -0.178, p = 0.037). The number of APOE epsilon 4 alleles was positively correlated with the whole-brain volume (r = 0.185, p = 0.030). It was also correlated with Wechsler Adult Intelligence Scale-Revised performance IQ (r = 0.203, p = 0.017) and with Wechsler Memory Scale-Revised attention/concentration score (r = 0.191, p = 0.025). CONCLUSIONS: Different patterns of regional brain atrophy were found among patients of different APOE genotypes. The effect of APOE epsilon 4 allele on the brains of AD patients may have regional specificity.

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PubMed2000

Visuoperceptual impairment in dementia with Lewy bodies.

BACKGROUND: In dementia with Lewy bodies (DLB), vision-related cognitive and behavioral symptoms are common, and involvement of the occipital visual cortices has been demonstrated in functional neuroimaging studies. OBJECTIVES: To delineate visuoperceptual disturbance in patients with DLB in comparison with that in patients with Alzheimer disease and to explore the relationship between visuoperceptual disturbance and the vision-related cognitive and behavioral symptoms. DESIGN: Case-control study. SETTING: Research-oriented hospital. PATIENTS: Twenty-four patients with probable DLB (based on criteria of the Consortium on DLB International Workshop) and 48 patients with probable Alzheimer disease (based on criteria of the National Institute of Neurological and Communicative Disorders and Stroke-Alzheimer's Disease and Related Disorders Association) who were matched to those with DLB 2:1 by age, sex, education, and Mini-Mental State Examination score. MAIN OUTCOME MEASURES: Four test items to examine visuoperceptual functions, including the object size discrimination, form discrimination, overlapping figure identification, and visual counting tasks. RESULTS: Compared with patients with probable Alzheimer disease, patients with probable DLB scored significantly lower on all the visuoperceptive tasks (P<.04 to P<.001). In the DLB group, patients with visual hallucinations (n = 18) scored significantly lower on the overlapping figure identification (P = .01) than those without them (n = 6), and patients with television misidentifications (n = 5) scored significantly lower on the size discrimination (P<.001), form discrimination (P = .01), and visual counting (P = .007) than those without them (n = 19). CONCLUSIONS: Visual perception is defective in probable DLB. The defective visual perception plays a role in development of visual hallucinations, delusional misidentifications, visual agnosias, and visuoconstructive disability charcteristic of DLB.

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PubMed2000

Left frontotemporal hypoperfusion is associated with aggression in patients with dementia.

BACKGROUND: Aggressive behavior is common in patients with dementia. Temporolimbic and prefrontal cortical lesions can produce pathological aggression; however, involvement of these structures has not been established in aggressive patients with dementia. OBJECTIVE: To study the relation between regional brain perfusion and aggressive behavior in patients with dementia. METHODS: We compared the pattern of regional cerebral perfusion determined with technetium Tc 99m-labeled hexamethylpropelene amineoxime single photon emission computed tomography in 2 groups of 10 patients with dementia with and without aggression, that were comparable for demographic factors, severity of cognitive impairments, and other behavioral symptoms as measured by the Neuropsychiatric Inventory. RESULTS: Patients with aggression revealed significant (P<.001) hypoperfusion in the left anterior temporal cortex; additional bilateral dorsofrontal and right parietal cortex were also found to be significantly hypoperfused. CONCLUSION: These results indicated an association between aggression and decreased perfusion in the left anterior temporal cortex. Arch Neurol. 2000.

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PubMed2000

Interrater reliability of the short-memory questionnaire in a variety of health professional representatives.

A study was performed to assess interrater reliability of the Japanese version of the Short-Memory Questionnaire (SMQ), which is an easily-administered, informant-based scale of cognitive function. The subjects were 18 consecutive patients with Alzheimer's disease who were outpatients of Department of Neuropsychiatry in Ehime University School of Medicine and their principal caregivers. One neuropsychiatrist (NP) administered the SMQ, and all sessions were videotaped. Then one nurse (Ns), one clinical psychologist (CP), one occupational therapist (OT), and one neurologist (NL) from another institution viewed the videotape and performed reassessments independently. Interrater reliability between the NP and Ns, CP, OT, or NL were all extremely good. Interrater reliability between the Ns and CP, between the Ns and OT, between the Ns and NL, between the CP and OT, between the CP and NL, and between the OT and NL were also extremely good. The SMQ is a convenient, quantitative scale, and in this study it showed good interrater reliability between personnel from different fields. Therefore, it is a very useful test for everyday medical consultations and for clinical research.

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PubMed2000

Validity of the Short-Memory Questionnaire in vascular dementia.

PURPOSE: To determine whether the Short-Memory Questionnaire (SMQ) being administered by caregivers to patients with Alzheimer's disease (AD) is also valid when given to patients with vascular dementia (VaD). METHODS: Subjects were 58 patients with VaD, 26 patients with cerebrovascular disorders free of cognitive deficit (CVD) and 62 healthy controls. All subjects received the Mini-Mental State Examination (MMSE), and their primary caregivers (or family members with same household) received the SMQ. RESULTS: In the VaD patients, the SMQ score was highly correlated with the MMSE score. When 39/40 was defined as a cutoff point based on the results of previous study, the SMQ properly classified 55 of the 58 VaD patients and 61 of the 62 controls, but only about half of the 26 CVD patients, as cases. CONCLUSION: The SMQ, a simple quantitative rating test for memory disturbance, is useful for the assessment and screening of VaD patients as well as AD patients, although careful attention should be paid to the assessment of CVD patients.

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PubMed2000

A diagnostic method for suspected Alzheimer's disease using H(2)15O positron emission tomography perfusion Z score.

We developed cerebral perfusion Z score map (Z map) images using H(2)15O and positron emission tomography (PET), and examined their use in diagnosing Alzheimer's disease (AD). Cerebral blood flow (CBF) images were obtained using the PET and H(2)15O autoradiographic method. The best region for normalising the CBF value to remove individual variantion was determined. Then CBF images were transformed to Talairach's standard space, and each pixel value of an individual's image set was normalized to the mean value of the sensorimotor area. Based on the CBF images of 20 normal volunteers, normative mean and standard deviation (SD) CBF images were constructed. Then, each pixel value of the axial CBF images in 28 patients with probable AD and 10 further normal volunteers was converted to a Z score (Z = [normal mean--individual value]/normal SD). A Z map, showing pixels exceeding a threshold of Z score > 2 on MRI of standardised anatomical space was demonstrated. These 38 Z maps were interpreted by four radiologists. When regions in the temporoparietal area were found with Z scores > 2, the subject was diagnosed as having AD. A receiver operating characteristic (ROC) analysis was performed to compare the conventional CBF images and Z maps. The diagnostic performance of the Z map was superior to that of visual inspection of conventional CBF images (mean areas under the ROC curve of the four radiologists were 0.946 and 0.584, respectively). These results indicate that a Z map obtained in this way is superior to conventional PET for diagnosing AD.

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PubMed2000

Disturbances of spatial vision and object vision correlate differently with regional cerebral glucose metabolism in Alzheimer's disease.

There is evidence of two neuronal systems for visual cognition which are referred to as spatial vision and object vision. We subjected 49 patients with mild-to-moderate probable Alzheimer's disease (AD) to tasks associated with these two types of visual cognition. Visual counting was employed as a task to assess visuospatial recognition. Identification of overlapping figures and discrimination of visual forms were used as visuoperceptual tasks that require an ability to recognize objects. Regional cerebral glucose metabolism (rCMRglc) of the subjects was also determined by positron emission tomography. Multivariate statistics controlling for the confounding factors assessed the correlation between the task performances and the rCMRglc. The visual counting score significantly correlated with the metabolic rate of the bilateral inferior parietal lobules. On the other hand, the scores of the visuoperceptual tasks significantly correlated with the metabolic rate of the right middle temporal gyrus and the right inferior parietal lobule. The present study showed that visuospatial disturbance was related to bilateral parietal metabolism, and that visuoperceptual disturbance was related to right temporo-parietal metabolism in patients with mild-to-moderate AD.

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PubMed2000

Fall-related injuries in dementia with Lewy bodies (DLB) and Alzheimer's disease.

Repeated falls are reported as one of the clinical characteristics in dementia with Lewy bodies (DLB). We examined the incidence of fall-related injuries in 561 dementia patients with various clinical diagnoses, including DLB and Alzheimer's disease (AD), in a ward established for dementia research. The incidence of fall-related injuries was significantly higher in DLB patients (10.7%) than in AD patients (1.1%) (P < 0.001). The high incidence in those patients with DLB cannot be attributed to Parkinsonism because none of the DLB patients with injuries showed extrapyramidal sign. Our observations suggest that patients with a clinical diagnosis of DLB have a high risk of fall-related injuries, even though they do not show Parkinsonism. An appropriate clinical discrimination between DLB and AD is recommended to manage and prevent fall-related injuries.

Accidental Falls↗
PubMed2000

Corticobasal degeneration: evaluation of cortical atrophy by means of hemispheric surface display generated with MR images.

PURPOSE: To determine the characteristics of cortical atrophy in corticobasal degeneration and Alzheimer disease by using a hemispheric surface display generated with magnetic resonance (MR) images. MATERIALS AND METHODS: The magnitude and extent of cortical atrophy were evaluated with MR hemispheric surface display and volumetric measurement in three groups: 17 patients with corticobasal degeneration, 17 matched patients with Alzheimer disease, and 17 matched healthy control subjects. RESULTS: The extent and magnitude of cortical atrophy were larger in the group with corticobasal degeneration than in the group with Alzheimer disease. The parasagittal and paracentral regions were significantly more atrophic in patients with corticobasal degeneration than in patients with Alzheimer disease (P <.05). The mean hemispheric-to-total intracranial volume ratios were significantly smaller in the patients with corticobasal degeneration (61%) and those with Alzheimer disease (64%) than in control subjects (69%). Asymmetry of hemispheric volume was significantly larger in the group with corticobasal degeneration than in the control group. CONCLUSION: The extent of cortical atrophy in corticobasal degeneration is more widespread than was previously thought. Parasagittal and paracentral atrophy is a distinctive feature of corticobasal degeneration and distinguishes it from Alzheimer disease.

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PubMed2000

Effect of the apolipoprotein E epsilon4 allele on white matter hyperintensities in dementia.

BACKGROUND AND PURPOSE: The clinical significance of the apoE epsilon4 allele in white matter changes in patients with dementia has been a subject of debate. We studied the association between the apoE epsilon4 allele and white matter hyperintensities (WMHs) before and after control for (1) potential vascular risk factors and (2) the presence of lacunar infarcts in patients with dementia. METHODS: The subjects were 131 patients with dementia who had either Alzheimer's disease or vascular dementia, or a combination of these 2 types of dementia, with or without WMHs, lacunar infarcts, or both. The association of the epsilon4 allele with WMHs was examined before and after control for age, sex, duration of symptoms, education level, severity of dementia, presence of lacunar infarcts, and potential vascular risk factors, including hypertension, diabetes mellitus, lipid disorders, smoking habit, drinking habit, and cardiac diseases. RESULTS: WMHs were observed in 73 (55.7%) of the patients. Neither the number of apoE epsilon4 alleles nor their presence was significantly associated with WMHs before or after control for the potential confounding factors. Multiple logistic regression analyses revealed that age, the presence of hypertension, and the presence of lacunar infarcts were independently associated with WMHs. CONCLUSIONS: The apoE epsilon4 allele was not associated with WMHs in patients with dementia. The fact that WMHs were significantly associated with hypertension and lacunar infarcts may indicate an ischemic origin of WMHs.

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PubMed2000

Impact of white matter changes on clinical manifestation of Alzheimer's disease: A quantitative study.

BACKGROUND AND PURPOSE: There have been conflicting results involving the clinical significance of white matter changes in patients with Alzheimer's disease (AD). We studied the association between the volume of white matter hyperintensities (WMHs) on T2-weighted images and cognitive, neurological, and neuropsychiatric symptoms. METHODS: The subjects were 76 AD patients who had WMHs but no obvious cerebrovascular diseases. We quantified the volume of WMHs by using fast-fluid-attenuated inversion recovery images and whole brain atrophy by using 3D spoiled gradient-echo images. Effects of WMHs and brain atrophy on dementia severity, cognitive function, neuropsychiatric disturbances, and neurological findings were examined. RESULTS: Whole brain atrophy was significantly associated with dementia severity and cognitive disturbances, as well as with grasp reflex and some kinds of neuropsychiatric disturbances. After we controlled for the effects of brain atrophy, duration of symptoms, and demographic factors, we found that WMH volume was not associated with global cognitive disturbances or dementia severity but was significantly associated with urinary incontinence, grasp reflex, and aberrant motor behaviors. Brain atrophy and WMH volume were not significantly correlated either before or after controlling for age, sex, education, and duration of symptoms. WMH volume was associated with hypertension, but brain atrophy was not positively correlated with any vascular risk factors. CONCLUSIONS: Our results support the hypothesis that WMHs in AD patients are superimposed phenomena of vascular origin. WMHs contribute to specific neurological and neuropsychiatric manifestations but not to global cognitive impairment, which is more closely associated with brain atrophy.

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PubMed2000

Impact of emotion on memory. Controlled study of the influence of emotionally charged material on declarative memory in Alzheimer's disease.

BACKGROUND: In an earlier study we showed that a powerful emotional experience (the Kobe earthquake) reinforced memory retention in patients with Alzheimer's disease, but we could not control factors other than the emotional impact of the earthquake. AIMS: To test our previous findings in a controlled experimental study. METHOD: Recall tests consisting of two short stories were administered to 34 patients with Alzheimer's disease and 10 normal subjects. The two stories were identical except for one passage in each story: one was emotionally charged (arousing story) and the other (neutral story) was not. RESULTS: In both groups, the emotionally charged passage in the arousing story was remembered better than the counterpart in the neutral story. In addition, the extent of the memory improvement was similar in the subjects and in the controls. CONCLUSIONS: The results provide further evidence that emotional arousal enhances declarative memory in patients with Alzheimer's disease, and give a clue to the management of people with dementia.

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PubMed1999

Regional cerebral blood flow difference between dementia with Lewy bodies and AD.

The authors studied 14 patients with dementia with Lewy bodies (DLB), 14 patients with AD, and 14 healthy control subjects with N-isopropyl-p-[123I]iodoamphetamine SPECT. Comparison with the statistical parametric mappings revealed that relative cerebral blood flow was lower in the occipital lobes and higher in the right medial temporal lobe in the DLB group than in the AD group. Decreased occipital perfusion and relatively well preserved medial temporal perfusion are features that distinguish DLB from AD.

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PubMed1999

Visual hallucinations and regional cerebral metabolism in dementia with Lewy bodies (DLB).

To investigate the neurobiological bases of visual hallucinations in dementia with Lewy bodies (DLB), regional cerebral glucose metabolism was compared among three patient groups; DLB with visual hallucinations, DLB without visual hallucinations and Alzheimer's disease (AD) without visual hallucinations. The regional metabolism was significantly lower in both DLB groups than in the AD group in the primary visual area and the posterior temporal, parietal and lateral occipital association areas. The hypometabolism in the right posterior temporal and parietal areas was significantly milder in DLB with visual hallucinations than in DLB without hallucinations. The hypometabolism in the primary visual cortex and the relatively preserved metabolism in the right temporoparietal association cortices may be associated with the occurrence of visual hallucinations in DLB patients.

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PubMed1999

Neuropsychiatric aspects of dementia with Lewy bodies.

Neuropsychiatric symptoms are prominent clinical features of dementia with Lewy bodies (DLB). Visual hallucinations have been reported to be particularly common. Auditory hallucinations, delusions, and depression also may be characteristic to DLB. Misidentification delusions may be more common than with other types of delusional syndromes. Supersensitivity to neuroleptic drugs is common, making treatment of these symptoms difficult, and newer, atypical compounds have been recommended. However, supersensitive reactions to these medicines have been reported. Patients with DLB, especially those with visual hallucinations, are reported to have a marked cholinergic deficit, and cholinergic drugs may be beneficial in reducing the neuropsychiatric symptoms.

Antipsychotic Agents↗