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1.
AJNR Am J Neuroradiol ; 44(7): 768-775, 2023 07.
Article in English | MEDLINE | ID: mdl-37348967

ABSTRACT

BACKGROUND AND PURPOSE: While brain iron dysregulation has been observed in several neurodegenerative disorders, its association with the progressive neurodegeneration in Niemann-Pick type C is unknown. Systemic iron abnormalities have been reported in patients with Niemann-Pick type C and in animal models of Niemann-Pick type C. In this study, we examined brain iron using quantitative susceptibility mapping MR imaging in individuals with Niemann-Pick type C compared with healthy controls. MATERIALS AND METHODS: A cohort of 10 patients with adolescent- and adult-onset Niemann-Pick type C and 14 age- and sex-matched healthy controls underwent 7T brain MR imaging with T1 and quantitative susceptibility mapping acquisitions. A probing whole-brain voxelwise comparison of quantitative susceptibility mapping between groups was conducted. Mean quantitative susceptibility mapping in the ROIs (thalamus, hippocampus, putamen, caudate nucleus, and globus pallidus) was further compared. The correlations between regional volume, quantitative susceptibility mapping values, and clinical features, which included disease severity on the Iturriaga scale, cognitive function, and the Social and Occupational Functioning Assessment Scale, were explored as secondary analyses. RESULTS: We observed lower volume in the thalamus and voxel clusters of higher quantitative susceptibility mapping in the pulvinar nuclei bilaterally in patients with Niemann-Pick type C compared with the control group. In patients with Niemann-Pick type C, higher quantitative susceptibility mapping in the pulvinar nucleus clusters correlated with lower volume of the thalamus on both sides. Moreover, higher quantitative susceptibility mapping in the right pulvinar cluster was associated with greater disease severity. CONCLUSIONS: Our findings suggest iron deposition in the pulvinar nucleus in Niemann-Pick type C disease, which is associated with thalamic atrophy and disease severity. This preliminary evidence supports the link between iron and neurodegeneration in Niemann-Pick type C, in line with existing literature on other neurodegenerative disorders.


Subject(s)
Iron , Niemann-Pick Disease, Type C , Humans , Brain/diagnostic imaging , Thalamus , Cognition , Magnetic Resonance Imaging/methods , Brain Mapping
2.
J Neurol Sci ; 432: 120088, 2022 Jan 15.
Article in English | MEDLINE | ID: mdl-34922179

ABSTRACT

INTRODUCTION: Determining disease severity and predicting prognosis in younger onset-dementia (YOD) remains challenging. Whether CSF biomarkers neurofilament light (NfL), tau and amyloidß 42 (Aß42) can help provide such information has been underexplored. METHODS: Patients with YOD and CSF analysis were identified. We compared baseline NfL, tau and Aß42 concentrations with contemporaneous Neuropsychiatry Unit Cognitive Assessment Tool (NUCOG) scores to assess their association with severity of cognitive impairment. Cognitive decline, as measured by longitudinal NUCOG assessment, was correlated against baseline biomarker levels to assess their utility in predicting the rate of cognitive decline. RESULTS: 78 patients with YOD (mean age = 56 years, SD = 8) and CSF analysis were identified. Dementia types included Alzheimer's disease, behavioural variant frontotemporal dementia, dementia not-otherwise-specified and other. Tau was associated with contemporaneous memory dysfunction (r = -0.556, 95% CI:[-0.702,-0.393], p < .001). 21 patients had longitudinal cognitive assessment up to 82 months from CSF sampling. NfL was associated with the rate of executive function decline (r = 0.755, 95% CI:[0.259,0.937], p < .001). Aß42 was associated with the rate of memory decline (r = -0.582, 95% CI:[-0.855,-0.274], p = .007) and rate of total NUCOG decline (r = -0.515, 95% CI: [-0.809, -0.227], p = .017). CONCLUSION: CSF tau is related to contemporaneous memory impairment in YOD. NfL and Aß42 levels are associated with the rate of executive function and memory decline, respectively, and may have a role in prognostication in YOD.


Subject(s)
Alzheimer Disease , Cognitive Dysfunction , Amyloid beta-Peptides , Biomarkers , Executive Function , Humans , Intermediate Filaments , Middle Aged , Neurofilament Proteins , Peptide Fragments , tau Proteins
3.
Eur J Nucl Med Mol Imaging ; 46(5): 1132-1138, 2019 May.
Article in English | MEDLINE | ID: mdl-30690666

ABSTRACT

PURPOSE: Niemann-Pick type C (NPC) is a cholesterol storage disease characterized by disruption in the endosomal-lysosomal transport system that leads to the accumulation of cholesterol and glycolipids in lysosomes. Developmental cognitive delay and progressive motor and cognitive impairment are characteristic of the disease. Tau accumulation has been reported in some NPC patients. We investigated the presence of tau and Aß-amyloid deposits in a group of NPC patients and for comparison in age-matched healthy controls (HC). METHODS: Eight NPC patients and seven HC were included in the study. Participants underwent tau imaging with 18F-AV1451 and amyloid imaging with 11C-PiB. Both 18F-AV1451 and 11C-PiB standardized uptake value ratios were generated using the cerebellar cortex as the reference region. Associations between imaging results, and clinical and neurocognitive parameters were assessed through nonparametric analyses. RESULTS: All participants were Aß-negative. Four NPC patients presented with high tau burden in the brain. A 21-year-old female patient and a 40-year-old male patient showed high neocortical tau burden in a pattern different from that observed in patients with Alzheimer's disease, while the same 40-year-old male patient, a 40-year-old female patient and a 50-year-old female patient showed high regional tau burden in the mesial temporal cortex. Spearman's correlation analysis showed an association between tau burden in the mesial temporal lobe and age (p = 0.022), and age at symptom onset (p = 0.009), and between frontotemporal tau and duration of symptoms (p = 0.027). There were no correlations between global and regional tau and cognitive parameters. CONCLUSION: Four of eight NPC patients showed tau deposition in the brain. The results of our exploratory study suggest that while tau deposits do not affect cognitive performance, tau deposits are associated with measures of disease onset and progression. Further studies in a larger cohort of NPC patients are needed to confirm these initial findings.


Subject(s)
Magnetic Resonance Imaging , Niemann-Pick Disease, Type C/diagnostic imaging , Niemann-Pick Disease, Type C/metabolism , tau Proteins/metabolism , Adolescent , Adult , Case-Control Studies , Female , Humans , Male , Middle Aged , Young Adult
4.
Psychol Med ; 48(1): 132-141, 2018 Jan.
Article in English | MEDLINE | ID: mdl-28625185

ABSTRACT

BACKGROUND: Cognitive deficits are a core feature of schizophrenia, and impairments in most domains are thought to be stable over the course of the illness. However, cross-sectional evidence indicates that some areas of cognition, such as visuospatial associative memory, may be preserved in the early stages of psychosis, but become impaired in later established illness stages. This longitudinal study investigated change in visuospatial and verbal associative memory following psychosis onset. METHODS: In total 95 first-episode psychosis (FEP) patients and 63 healthy controls (HC) were assessed on neuropsychological tests at baseline, with 38 FEP and 22 HCs returning for follow-up assessment at 5-11 years. Visuospatial associative memory was assessed using the Cambridge Neuropsychological Test Automated Battery Visuospatial Paired-Associate Learning task, and verbal associative memory was assessed using Verbal Paired Associates subtest of the Wechsler Memory Scale - Revised. RESULTS: Visuospatial and verbal associative memory at baseline did not differ significantly between FEP patients and HCs. However, over follow-up, visuospatial associative memory deteriorated significantly for the FEP group, relative to healthy individuals. Conversely, verbal associative memory improved to a similar degree observed in HCs. In the FEP cohort, visuospatial (but not verbal) associative memory ability at baseline was associated with functional outcome at follow-up. CONCLUSIONS: Areas of cognition that develop prior to psychosis onset, such as visuospatial and verbal associative memory, may be preserved early in the illness. Later deterioration in visuospatial memory ability may relate to progressive structural and functional brain abnormalities that occurs following psychosis onset.


Subject(s)
Cognition , Psychotic Disorders/psychology , Schizophrenia/physiopathology , Spatial Memory , Adolescent , Adult , Australia , Case-Control Studies , Cross-Sectional Studies , Female , Follow-Up Studies , Humans , Male , Psychiatric Status Rating Scales , Regression Analysis , Visual Perception , Young Adult
5.
AJNR Am J Neuroradiol ; 37(11): E79, 2016 Nov.
Article in English | MEDLINE | ID: mdl-27585703
6.
AJNR Am J Neuroradiol ; 37(5): 774-81, 2016 05.
Article in English | MEDLINE | ID: mdl-26744445

ABSTRACT

Visual hallucinations are relatively uncommon presentations in medical and psychiatric clinics, where they are generally regarded as a marker of possible underlying "organic" brain disease. Thus, patients with visual hallucinations are often referred for imaging of the brain. This article presents a pragmatic approach for the radiologist reviewing such imaging. Because conditions that can present with visual hallucinations are legion, a familiarity with the features of the hallucinations themselves, which can serve as clues to the underlying cause, can be helpful in interpreting such cases. We consider the nature of visual hallucinations and the mechanisms underlying their formation. We then provide a framework to guide the search for their cause, first in terms of focal lesions along the visual pathway and then global conditions affecting >1 region.


Subject(s)
Brain Diseases/diagnostic imaging , Brain/diagnostic imaging , Hallucinations/diagnostic imaging , Visual Pathways/diagnostic imaging , Female , Humans , Male , Neuroimaging
7.
Psychol Med ; 45(3): 515-27, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25077698

ABSTRACT

BACKGROUND: Whether there are differential effects of first-generation antipsychotics (FGAs) and second-generation antipsychotics (SGAs) on the brain is currently debated. Although some studies report that FGAs reduce grey matter more than SGAs, others do not, and research to date is limited by a focus on schizophrenia spectrum disorders. To address this limitation, this study investigated the effects of medication in patients being treated for first-episode schizophrenia or affective psychoses. METHOD: Cortical thickness was compared between 52 first-episode psychosis patients separated into diagnostic (i.e. schizophrenia or affective psychosis) and medication (i.e. FGA and SGA) subgroups. Patients in each group were also compared to age- and sex-matched healthy controls (n = 28). A whole-brain cortical thickness interaction analysis of medication and diagnosis was then performed. Correlations between cortical thickness with antipsychotic dose and psychotic symptoms were examined. RESULTS: The effects of medication and diagnosis did not interact, suggesting independent effects. Compared with controls, diagnostic differences were found in frontal, parietal and temporal regions. Decreased thickness in FGA-treated versus SGA-treated groups was found in a large frontoparietal region (p < 0.001, corrected). Comparisons with healthy controls revealed decreased cortical thickness in the FGA group whereas the SGA group showed increases in addition to decreases. In FGA-treated patients cortical thinning was associated with higher negative symptoms whereas increased cortical thickness in the SGA-treated group was associated with lower positive symptoms. CONCLUSIONS: Our results suggest that FGA and SGA treatments have divergent effects on cortical thickness during the first episode of psychosis that are independent from changes due to illness.


Subject(s)
Affective Disorders, Psychotic/drug therapy , Antipsychotic Agents/classification , Antipsychotic Agents/therapeutic use , Cerebral Cortex/anatomy & histology , Cerebral Cortex/drug effects , Schizophrenia/drug therapy , Adolescent , Adult , Case-Control Studies , Female , Humans , Magnetic Resonance Imaging , Male , Young Adult
8.
Psychol Med ; 44(3): 489-98, 2014 Feb.
Article in English | MEDLINE | ID: mdl-23659473

ABSTRACT

BACKGROUND: Grey matter volume and cortical thickness represent two complementary aspects of brain structure. Several studies have described reductions in grey matter volume in people at ultra-high risk (UHR) of psychosis; however, little is known about cortical thickness in this group. The aim of the present study was to investigate cortical thickness alterations in UHR subjects and compare individuals who subsequently did and did not develop psychosis. METHOD: We examined magnetic resonance imaging data collected at four different scanning sites. The UHR subjects were followed up for at least 2 years. Subsequent to scanning, 50 UHR subjects developed psychosis and 117 did not. Cortical thickness was examined in regions previously identified as sites of neuroanatomical alterations in UHR subjects, using voxel-based cortical thickness. RESULTS: At baseline UHR subjects, compared with controls, showed reduced cortical thickness in the right parahippocampal gyrus (p < 0.05, familywise error corrected). There were no significant differences in cortical thickness between the UHR subjects who later developed psychosis and those who did not. CONCLUSIONS: These data suggest that UHR symptomatology is characterized by alterations in the thickness of the medial temporal cortex. We did not find evidence that the later progression to psychosis was linked to additional alterations in cortical thickness, although we cannot exclude the possibility that the study lacked sufficient power to detect such differences.


Subject(s)
Parahippocampal Gyrus/pathology , Psychotic Disorders/pathology , Adolescent , Adult , Case-Control Studies , Data Interpretation, Statistical , Disease Progression , Disease Susceptibility/pathology , Female , Follow-Up Studies , Humans , Image Processing, Computer-Assisted/methods , Magnetic Resonance Imaging/methods , Male , Organ Size/physiology , Prodromal Symptoms , Risk Assessment , Young Adult
9.
Transl Psychiatry ; 3: e251, 2013 Apr 30.
Article in English | MEDLINE | ID: mdl-23632455

ABSTRACT

Prospective studies have suggested genetic variation in the neuregulin 1 (NRG1) and D-amino-acid oxidase activator (DAOA) genes may assist in differentiating high-risk individuals who will or will not transition to psychosis. In a prospective cohort (follow-up=2.4-14.9 years) of 225 individuals at ultra-high risk (UHR) for psychosis, we assessed haplotype-tagging single-nucleotide polymorphisms (htSNPs) spanning NRG1 and DAOA for their association with transition to psychosis, using Cox regression analysis. Two NRG1 htSNPs (rs12155594 and rs4281084) predicted transition to psychosis. Carriers of the rs12155594 T/T or T/C genotype had a 2.34 (95% confidence interval (CI)=1.37-4.00) times greater risk of transition compared with C/C carriers. For every rs4281084 A-allele the risk of transition increased by 1.55 (95% CI=1.05-2.27). For every additional rs4281084-A and/or rs12155594-T allele carried the risk increased ∼1.5-fold, with 71.4% of those carrying a combination of 3 of these alleles transitioning to psychosis. None of the assessed DAOA htSNPs were associated with transition. Our findings suggest NRG1 genetic variation may improve our ability to identify UHR individuals at risk for transition to psychosis.


Subject(s)
Carrier Proteins/genetics , Neuregulin-1/genetics , Polymorphism, Single Nucleotide/genetics , Psychotic Disorders/genetics , Adolescent , Adult , Carrier Proteins/physiology , Female , Genetic Predisposition to Disease/genetics , Genotype , Haplotypes/genetics , Heterozygote , Humans , Intracellular Signaling Peptides and Proteins , Male , Neuregulin-1/physiology , Proportional Hazards Models , Prospective Studies , Psychiatric Status Rating Scales , Risk Factors , Young Adult
10.
AJNR Am J Neuroradiol ; 34(7): 1334-40, 2013 Jul.
Article in English | MEDLINE | ID: mdl-23237858

ABSTRACT

BACKGROUND AND PURPOSE: Voxel-based analysis has suggested that deep gray matter rather than cortical regions is initially affected in adult Niemann-Pick type C. We sought to examine a range of deep gray matter structures in adults with NPC and relate these to clinical variables. MATERIALS AND METHODS: Ten adult patients with NPC (18-49 years of age) were compared with 27 age- and sex-matched controls, and subcortical structures were automatically segmented from normalized T1-weighted MR images. Absolute volumes (in cubic millimeters) were generated for a range of deep gray matter structures and were compared between groups and correlated with illness variables. RESULTS: Most structures were smaller in patients with NPC compared with controls. The thalamus, hippocampus, and striatum showed the greatest and most significant reductions, and left hippocampal volume correlated with symptom score and cognition. Vertex analysis of the thalamus, hippocampus, and caudate implicated regions involved in memory, executive function, and motor control. CONCLUSIONS: Thalamic and hippocampal reductions may underpin the memory and executive deficits seen in adult NPC. Volume losses in other subcortical regions may also be involved in the characteristic range of motor, psychiatric, and cognitive deficits seen in the disease.


Subject(s)
Brain/pathology , Magnetic Resonance Imaging/methods , Niemann-Pick Disease, Type C/pathology , Adolescent , Adult , Amygdala/pathology , Case-Control Studies , Caudate Nucleus/pathology , Cognition/physiology , Cohort Studies , Corpus Striatum/pathology , Cross-Sectional Studies , Executive Function/physiology , Female , Hippocampus/pathology , Humans , Image Enhancement/methods , Image Processing, Computer-Assisted/methods , Imaging, Three-Dimensional/methods , Male , Memory/physiology , Middle Aged , Motor Skills/physiology , Organ Size , Putamen/pathology , Thalamus/pathology , Young Adult
11.
Eur J Neurol ; 19(3): 462-7, 2012 Mar.
Article in English | MEDLINE | ID: mdl-22329857

ABSTRACT

BACKGROUND AND PURPOSE: Niemann-Pick disease type C (NPC) is a progressive neurovisceral disorder associated with dystonia, ataxia and a characteristic gaze palsy. Neuropathological studies have demonstrated brainstem atrophy associated with neuronal inclusions and loss, and neurofibrillary tangles, although it is not known whether this pathology can be detected in vivo or how these changes relate to illness variables, particularly ocular-motor changes. Our aim was to utilize a method for brainstem atrophy, validated in progressive supranuclear palsy (PSP), in a group of adult patients with NPC, and explore its relationship to illness variables and ocular-motor functioning. METHODS: We calculated the midbrain and pontine area, and pontine-to-midbrain ratio (PMR) from midsagittal images of 10 adult patients with NPC and 27 age- and gender-matched controls. Measures were correlated with illness variables, and measures of horizontal saccadic functioning. RESULTS: Pontine-to-midbrain ratio was 14% higher in the NPC group, but this difference was not significant. However, PMR showed a significant positive correlation with duration of illness and a measure of illness severity. Furthermore, PMR was significantly negatively correlated with saccadic peak velocity and gain, and self-paced saccadic performance. CONCLUSIONS: Pontine-to-midbrain ratio was increased in adult patients with NPC compared to controls, although not to the same degree as previously described in PSP, which also presents with significant gaze palsy. These changes were driven predominantly by progressive midbrain atrophy. The strong correlation with illness and ocular-motor variables suggests that it may be a useful marker for illness progression in NPC.


Subject(s)
Brain Stem/pathology , Niemann-Pick Disease, Type C/pathology , Saccades/physiology , Adolescent , Adult , Brain Stem/physiopathology , Disease Progression , Female , Humans , Image Interpretation, Computer-Assisted , Magnetic Resonance Imaging , Male , Middle Aged , Niemann-Pick Disease, Type C/complications , Niemann-Pick Disease, Type C/physiopathology , Young Adult
12.
Psychiatriki ; 22(2): 120-31, 2011.
Article in Greek | MEDLINE | ID: mdl-21888185

ABSTRACT

The aim of this study is to compare the volumes of hippocampus, amygdala and subgenual prefrontal cortex among patients with melancholic depression, patients with psychotic depression and normal controls. Thirty nine patients with a diagnosis of major depression (22 with melancholic and 17 with psychotic subtype) and 18 normal controls were included in the study. Hippocampal, amygdala, anterior and posterior subgenual cortex volumes were measured by manual tracings on magnetic resonance volumetric images and compared across the 3 groups. We identified larger amygdala volumes and smaller left anterior subgenual cortex volumes in both patient groups compared to controls. There were no differences in hippocampal, right anterior and posterior subgenual cortex volumes across the 3 groups. In conclusion, melancholic and psychotic depression were not differentiated regarding the volumes of the hippocampus, the amygdala, and anterior and posterior subgenual cortex, even though amygdala volumes and left anterior subgenual cortex volume of both patient groups were differentiated compared to controls.


Subject(s)
Affective Disorders, Psychotic/diagnosis , Brain/pathology , Depressive Disorder, Major/diagnosis , Image Processing, Computer-Assisted/methods , Magnetic Resonance Imaging/methods , Adult , Affective Disorders, Psychotic/pathology , Aged , Amygdala/pathology , Cerebral Cortex/pathology , Corpus Callosum/pathology , Depressive Disorder, Major/pathology , Dominance, Cerebral/physiology , Female , Hippocampus/pathology , Humans , Male , Middle Aged , Organ Size/physiology , Reference Values
13.
AJNR Am J Neuroradiol ; 32(7): 1340-6, 2011 Aug.
Article in English | MEDLINE | ID: mdl-21596811

ABSTRACT

BACKGROUND AND PURPOSE: Variable alterations to the structure of the corpus callosum have been described in adults with NPC, a neurometabolic disorder known to result in both white and gray matter pathology. This study sought to examine the structure of the callosum in a group of adult patients with NPC and compared callosal structure with a group of matched controls, and to relate callosal structure with state and trait illness variables. MATERIALS AND METHODS: Nine adult patients with NPC were matched to control subjects (n = 26) on age and sex. The corpus callosum was segmented from the midsagittal section of T1-weighted images on all subjects, and total area, length, bending angle, and mean thickness were calculated. In addition, 39 regional thickness measures were derived by using a previously published method. All measures were compared between groups, and analyzed alongside symptom measures, biochemical parameters, and ocular-motor measures. RESULTS: The callosal area and mean thickness were significantly reduced in the patient group, and regional thickness differences were greatest in the genu, posterior body, isthmus, and anterior splenium. Global callosal measures correlated significantly with duration of illness and symptom score, and at trend level with degree of filipin staining. Measures of reflexive saccadic peak velocity and gain, and self-paced saccades, correlated strongly with total callosal area. CONCLUSIONS: Callosal structure and size reflect both state and trait markers in adult NPC, and they may be useful biomarkers to index both white and gray matter changes that reflect illness severity and progression.


Subject(s)
Corpus Callosum/pathology , Diffusion Tensor Imaging , Niemann-Pick Disease, Type C/pathology , Adolescent , Adult , Anatomic Landmarks/pathology , Disease Progression , Female , Humans , Leukoencephalopathies/pathology , Male , Middle Aged , Neurons/pathology , Severity of Illness Index , Young Adult
14.
Dement Geriatr Cogn Disord ; 29(6): 516-22, 2010.
Article in English | MEDLINE | ID: mdl-20523051

ABSTRACT

BACKGROUND/AIMS: Only a limited number of cognitive screening tools are available for the Persian-speaking population, and we sought to translate and validate the Neuropsychiatry Unit Cognitive Assessment Tool (NUCOG), a multidimensional cognitive screening tool. METHODS: We used multiple language specialists to translate and then back-translate the NUCOG, and administered the Persian language NUCOG and Mini-Mental State Examination (MMSE) to 184 individuals: 60 controls and 124 patients, 33 of whom had dementia, 30 non-dementing neurological disorders and 61 a psychiatric illness. RESULTS: The NUCOG outperformed the MMSE in differentiating the patient groups and controls. The 'profile' across the 5 NUCOG domains differentiated dementia subgroups such as senile dementia of the Alzheimer type (SDAT), frontotemporal dementia and mild cognitive impairment (MCI). Psychiatric patients with psychosis and posttraumatic stress disorder were more impaired than patients with affective disorders. The NUCOG reliably differentiated controls from patients with MCI (at 86.5/100, sensitivity of 83.3% and specificity of 87.5%) and SDAT (at 75/100, sensitivity and specificity of 100%) patients from controls. CONCLUSIONS: The Persian language NUCOG appears to perform strongly in an unselected population, reliably differentiating patients with dementia from controls, and detecting cognitive impairment in a range of clinical disorders.


Subject(s)
Cognition Disorders/diagnosis , Dementia/diagnosis , Diagnostic Techniques, Neurological , Neuropsychological Tests , Case-Control Studies , Central Nervous System Diseases/diagnosis , Cognition , Cross-Cultural Comparison , Dementia/classification , Diagnosis, Differential , Humans , Iran , Reference Values , Reproducibility of Results , Sensitivity and Specificity , Translations
15.
Neurology ; 75(1): 49-56, 2010 Jul 06.
Article in English | MEDLINE | ID: mdl-20484681

ABSTRACT

OBJECTIVE: Niemann-Pick disease type C (NPC) is a progressive neurovisceral disorder with disrupted intracellular cholesterol metabolism that results in significant alterations to neuronal and axonal structure. Adult patients present with ataxia, gaze palsy, impaired cognition, and neuropsychiatric illness, but the neural substrate has not been well-characterized in vivo. Our aim was to investigate a well-characterized sample of adults with confirmed NPC for gray and white matter abnormalities. METHODS: We utilized a combination of optimized voxel-based morphometry of T1-weighted images and tract-based spatial statistics of diffusion tensor images to examine gray matter volume and white matter structural differences in 6 adult patients with NPC and 18 gender- and age-matched controls. RESULTS: Patients with NPC demonstrated bilateral gray matter reductions in large clusters in bilateral hippocampus, thalamus, superior cerebellum, and insula, in addition to smaller regions of inferoposterior cortex. Patients demonstrated widespread reductions in fractional anisotropy in major white matter tracts. Subsequent analysis of measures of axial and radial diffusivity suggest that these changes are contributed to by both impaired myelination and altered axonal structure. CONCLUSIONS: Findings in gray matter areas are broadly consistent with human and animal studies of selective vulnerability of neuronal populations to the neuropathology of NPC, whereas more widespread white matter changes are consistent with the hypothesis that disrupted myelination and axonal structure predate changes to the neuronal cell body. These findings suggest that volumetric analysis of gray matter and diffusion tensor imaging may be useful modalities for indexing illness stage and monitoring response to emerging treatment.


Subject(s)
Cerebral Cortex/pathology , Nerve Fibers, Myelinated/pathology , Niemann-Pick Disease, Type C/pathology , Adolescent , Adult , Cross-Sectional Studies , Diffusion Tensor Imaging/methods , Female , Humans , Male , Young Adult
16.
Asian J Psychiatr ; 3(4): 186-9, 2010 Dec.
Article in English | MEDLINE | ID: mdl-23050885

ABSTRACT

The Neuropsychiatry Unit Cognitive Screening Instrument (NUCOG) provides more detailed screening of cognition than most commonly available tools and was selected for translation into and validation in Bahasa Malaysia (Malay language). It was first translated to Malay, then back-translated to English until changes made were comparable to the original English version. The Malay-translated NUCOG and the Malay version of the Mini-Mental State Examination (MMSE) were delivered to Malay-speaking subjects (n=24). The Malay NUCOG version was then validated by correlating scores against the Malay version of the MMSE and the data tested for reliability of the tool. The Malay version of the NUCOG proved to be a valid (r=0.98, p<0.001) and internally consistent (Cronbach's α=0.76) tool to assess cognitive function and this multi-dimensional cognitive screening instrument is likely to be valuable in the cognitive assessment of neuropsychiatric patients in Malay.

17.
J Inherit Metab Dis ; 32 Suppl 1: S221-6, 2009 Dec.
Article in English | MEDLINE | ID: mdl-19609713

ABSTRACT

We describe the differential presentation of schizophrenia-like psychosis in two siblings with the 'variant' biochemical presentation of adult Niemann-Pick disease type C. The male sibling presented with psychosis at age 16 years and cognitive and motor disturbance at age 25 years, whereas his elder sister, sharing the same mutation but showing less severe biochemical, neuroimaging and ocular motor parameters, presented with a similar schizophrenia-like illness with associated cognitive and motor disturbance at age 31 years. Their illness onset, course and response to treatment mirrors the sex dimorphism seen in schizophrenia, and is suggestive of an interaction between the neurobiology of their metabolic disorder and sex differences in neurodevelopment.


Subject(s)
Niemann-Pick Disease, Type C/genetics , Niemann-Pick Disease, Type C/psychology , Schizophrenia/genetics , Adolescent , Adult , Carrier Proteins/genetics , Female , Humans , Intracellular Signaling Peptides and Proteins , Male , Membrane Glycoproteins/genetics , Mutation , Niemann-Pick C1 Protein , Niemann-Pick Disease, Type C/complications , Schizophrenia/drug therapy , Schizophrenia/etiology , Schizophrenic Psychology , Sex Characteristics , Siblings , Young Adult
18.
Br J Psychiatry ; 194(4): 298-305, 2009 Apr.
Article in English | MEDLINE | ID: mdl-19336778

ABSTRACT

BACKGROUND: Few studies have investigated the relationship between schizophrenia and frontotemporal dementia. AIMS: To investigate this relationship through a clinicopathological investigation of young-onset frontotemporal dementia and a review of the case literature. METHOD: Cases of young-onset frontotemporal dementia were identified within the local brain bank. The clinical course and pathological findings were collated. For the literature review, cases of frontotemporal dementia identified through Medline were selected according to defined criteria. The demographic, clinical, pathological and genetic characteristics of cases presenting with a psychotic illness were identified. RESULTS: In the case series, 5 of 17 patients with frontotemporal dementia had presented with a psychotic illness (schizophrenia/schizoaffective disorder n=4, bipolar disorder n=1) an average of 5 years prior to the dementia diagnosis. Patients with schizophrenia exhibited changes consistent with TDP-43 and ubiquitin-positive frontotemporal dementia. In the cases review, a third of patients aged 30 years or under and a quarter of those aged 40 years or under had been diagnosed with psychosis at presentation. CONCLUSIONS: Patients with young-onset frontotemporal dementia may be diagnosed with a psychotic illness years before the dementia diagnosis is made. These findings have implications for clinicians and for our further understanding of the neurobiology of psychotic illness.


Subject(s)
Dementia/pathology , Schizophrenia/pathology , Adult , Age of Onset , DNA-Binding Proteins/genetics , Dementia/diagnosis , Female , Humans , Immunohistochemistry , Male , Middle Aged , Mutation/genetics , Regression Analysis , Schizophrenia/diagnosis , Young Adult , tau Proteins/metabolism
19.
Neurology ; 72(12): 1083-6, 2009 Mar 24.
Article in English | MEDLINE | ID: mdl-19307542

ABSTRACT

BACKGROUND: The autosomal recessive disorder Niemannn-Pick type C (NPC) presents in adulthood with psychosis or cognitive deficits associated with supranuclear gaze palsies. While saccadic innervation to the extraocular muscles is generated in the brainstem, the frontal lobes play an integral role in the initiation of volitional saccades and the suppression of unwanted reflexive saccades. No study has examined the frontally driven volitional control of saccadic eye movements in NPC. OBJECTIVE: To examine self-paced and antisaccades as well as reflexive saccades in adult patients with NPC, a disorder known to affect brainstem and frontal cortical function. METHODS: Three biochemically confirmed adult patients with NPC were compared with 10 matched controls on horizontal saccadic and antisaccadic measures using an infrared limbus eye tracker. Patients' cholesterol esterification and filipin staining, Mini-Mental State performance, and NPC symptom level were rated. RESULTS: Reflexive saccade latency ranged from shorter to longer than normal, reflexive saccade gain was reduced, asymptotic peak velocity was reduced, fewer self-paced saccades were generated, and increased errors on antisaccades were made by patients compared to controls. Patients with more severe biochemical, cognitive, and symptom deficits performed most poorly on brainstem and frontal ocular motor measures. Paradoxically, less severe illness was associated with an abnormally reduced saccadic latency. CONCLUSIONS: Ocular motor measures provide an index of disease severity in Niemannn-Pick type C (NPC) and may be a useful adjunct for monitoring the illness progress and medication response. Reduced saccadic latency may result from inadequate fixation input from abnormally functioning frontal eye fields in NPC.


Subject(s)
Brain Stem/physiopathology , Frontal Lobe/physiopathology , Niemann-Pick Disease, Type C/complications , Niemann-Pick Disease, Type C/physiopathology , Ocular Motility Disorders/etiology , Ocular Motility Disorders/physiopathology , Saccades/physiology , Adult , Biomarkers/analysis , Biomarkers/metabolism , Brain Stem/metabolism , Cholesterol/analysis , Cholesterol/metabolism , Disease Progression , Esterification/genetics , Female , Filipin/analysis , Filipin/metabolism , Frontal Lobe/metabolism , Humans , Male , Neurologic Examination , Neuropsychological Tests , Niemann-Pick Disease, Type C/metabolism , Ocular Motility Disorders/diagnosis , Predictive Value of Tests , Psychomotor Performance/physiology , Reaction Time/physiology , Reflex, Abnormal/physiology , Severity of Illness Index
20.
Mol Psychiatry ; 14(10): 976-86, 2009 Oct.
Article in English | MEDLINE | ID: mdl-18607377

ABSTRACT

Schizophrenia is associated with structural brain abnormalities, but the timing of onset and course of these changes remains unclear. Longitudinal magnetic resonance imaging (MRI) studies have demonstrated progressive brain volume decreases in patients around and after the onset of illness, although considerable discrepancies exist regarding which brain regions are affected. The anatomical pattern of these progressive changes in schizophrenia is largely unknown. In this study, MRI scans were acquired repeatedly from 16 schizophrenia patients approximately 2 years apart following their first episode of illness, and also from 14 age-matched healthy subjects. Cortical Pattern Matching, in combination with Structural Image Evaluation, using Normalisation, of Atrophy, was applied to compare the rates of cortical surface contraction between patients and controls. Surface contraction in the dorsal surfaces of the frontal lobe was significantly greater in patients with first-episode schizophrenia (FESZ) compared with healthy controls. Overall, brain surface contraction in patients and healthy controls showed similar anatomical patterns, with that of the former group exaggerated in magnitude across the entire brain surface. That the pattern of structural change in the early course of schizophrenia corresponds so closely to that associated with normal development is consistent with the hypothesis that a schizophrenia-related factor interacts with normal adolescent brain developmental processes in the pathophysiology of schizophrenia. The exaggerated progressive changes seen in patients with schizophrenia may reflect an increased rate of synaptic pruning, resulting in excessive loss of neuronal connectivity, as predicted by the late neurodevelopmental hypothesis of the illness.


Subject(s)
Brain/pathology , Magnetic Resonance Imaging , Schizophrenia/pathology , Adolescent , Adult , Atrophy , Brain Mapping , Case-Control Studies , Female , Humans , Longitudinal Studies , Magnetic Resonance Imaging/methods , Male , Organ Size
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