Chiung-Chih Chang

Effects of Long-Term Antiepileptic Drug Monotherapy on Vascular Risk Factors and Atherosclerosis.

Purpose:u2002 Long‐term therapy with antiepileptic drugs (AEDs) has been associated with metabolic consequences that lead to an increase in risk of atherosclerosis in patients with epilepsy. We compared the long‐term effects of monotherapy using different categories of AEDs on markers of vascular risk and the atherosclerotic process.

A comparative study of fused FDG PET/MRI, PET/CT, MRI, and CT imaging for assessing surrounding tissue invasion of advanced buccal squamous cell carcinoma.

Purpose: This study aimed to evaluate the diagnostic value of fused fluorodeoxyglucose positron emission tomography and magnetic resonance imaging (PET/MRI) compared with PET/computed tomography (CT), MRI, and CT in assessing surrounding tissue invasion of advanced buccal squamous cell carcinoma (BSCC). Materials and Methods: PET/CT and MRI were performed in 17 consecutive patients with suspected masticator space invasion of BSCC from CT images. Attenuation-corrected PET and head and neck MRI datasets were registered. For pathologic correlation, 4 regions of interest were examined, including the maxilla, mandible, pterygoid, and masseter muscle. The tumor maximal diameter, measured by different imaging modalities, was correlated with pathology results. Results: All PET/MRI fusions were verified as well matched using specific anatomic criteria. For pathology results, 1 patient had inflammation only, 1 had spindle cell cancer, and 15 had squamous cell cancer. Of 64 regions of interest, 20 (31.3%) harbored tumor invasion. The likelihood ratio was highest in fused PET/MRI (42.56) compared with PET/CT (25.02), MRI (22.94), and CT (8.6; all P < 0.05). The sensitivity and specificity of fused PET/MRI were also highest among the 4 modalities (90.0%/90.9%, 80.0%/84.1%, 80.0%/79.5%, and 55.0%/81.8%, respectively). The level of confidence was higher in fused PET/MRI or MRI than in PET/CT or CT (85.9%, 85.9%, 70.3%, 73.4%, respectively). The maximal lesion size was 3.0 to 6.0 cm in the pathology specimen. Regression analysis showed better agreement between fused PET/MRI and pathology results. Conclusions: Fused PET/MRI is more reliable for focal invasion assessment and tumor size delineation in advanced BSCC compared with PET/CT, MRI, and CT. PET/CT has the lowest confidence level, which may limit its use in the clinical setting.

Cerebrotendinous Xanthomatosis Patients With and Without Parkinsonism: Clinical Characteristics and Neuroimaging Findings

Parkinsonism in cerebrotendinous xanthomatosis (CTX) is rare. There are no published studies with imaging findings of dopamine transporter using 99mTc‐[2‐[[2‐[[[3‐(4‐chlorophenyl)‐8‐methyl‐8‐azabicyclo [3,2,1] oct‐2‐yl] methyl] (2‐mercaptoethyl) amino] ethyl] amino]‐ethanethiolato(3‐)‐N2,N2,S2,S2]oxo‐[1R‐(exo‐exo)] (99mTc‐TRODAT‐1) SPECT in CTX patients. This report is on the clinical details of five genetically‐proven CTX patients (two with and three without parkinsonism). Imaging findings using cranial magnetic resonance (MR) imaging and 99mTc‐TRODAT‐1 SPECT are also shown. Clinical correlation of neuroimaging findings and clinical presentations was made. A literature review of the clinical and neuroimaging features of eight CTX patients with parkinsonism reported in the English literature is also presented. The parkinsonian features of our two cases and the other eight reported cases occurred before the age of 50 years. The MR imaging study showed variable findings, in which, besides the common diffuse cerebral and cerebellar white matter lesions shown in CTX, several focal brain lesions were also noted. Of the focal lesions, substantia nigra abnormalities were seen only in the two cases with parkinsonism. The 99mTc‐TRODAT‐1 SPECT study showed different degrees of unilateral or bilateral abnormalities in the striatal binding in both visual and semiquantitative assessments. parkinsonism can be one of the neurologic presentations of CTX. Even though abnormal findings of the substantia nigra were detected in both of our CTX patients with parkinsonism, basal ganglion lesions have not been uniformly described in MR imaging findings of reported CTX patients with parkinsonism. 99mTc‐TRODAT‐1 SPECT study can be of value in the detection of striatal involvement, and the study results also suggest pre‐synaptic dopamine neuron involvement in CTX patients with parkinsonism.

Clinical characteristics of post-neurosurgical Klebsiella pneumoniae meningitis in adults and a clinical comparison to the spontaneous form in a Taiwanese population

A total of 46 patients (nine post-neurosurgical, 37 spontaneous) with adult bacterial meningitis (ABM) caused by Klebsiellapneumoniae infection were included in this study. The nine patients in the post-neurosurgical K. pneumoniae ABM group (seven male, two female) had a mean age of 48.9 years. Two patients in this group also had diabetes mellitus (DM) and one had liver disease. The most common presentation of patients in post-neurosurgical K. pneumoniae ABM group was fever (nine patients), followed by altered consciousness (seven patients) and hydrocephalus (six patients). With medical and/or surgical treatment, a mortality of 22.2% (2/9) occurred. Compared to patients who had spontaneous K. pneumoniae ABM, those with the post-neurosurgical form had a lower incidence of community-acquired infection, seizure and DM, but had a higher incidence of leukocytosis, hydrocephalus, cerebrospinal fluid leak and bacterial strains with extended-spectrum beta-lactamase. Univariate analysis found these clinical differences to be statistically significant, however they were not significant on multivariate analysis. This study reveals that there are clinical differences between the post-neurosurgical and spontaneous presentations of K. pneumoniae ABM.

Cortical metabolic and nigrostriatal abnormalities associated with clinical stage-specific dementia with Lewy bodies.

Purpose The aims of this study were to investigate the hypometabolic regions of FDG PET compared with the nigrostriatal dopamine pathway abnormalities in TRODAT-1 scan in patients with dementia with Lewy bodies (DLBs) at mild and dementia stages as well as to validate the correlation among networks being constructed with clinical data. Materials and Methods A total of 25 DLB patients were classified into 2 functional groups stratified by the Clinical Dementia Rating (CDR) Scale (CDR 0.5: n = 14, mild stage; CDR 1 or 2: n = 11, dementia stage) compared with 9 age-matched controls. Neuroimaging survey was applied using information derived from FDG PET by performing voxel-based analysis and a semiquantitative 99mTc-TRODAT-1 scan to correlate these results with the cognitive and Unified Parkinson’s Disease Rating Scale. Results Compared with normal database, the patients with mild stage showed hypometabolism in the temporal regions, anterior cingulate cortex, inferior orbital region, thalamus, and caudate nucleus. Although at the dementia stage, more extensive cortical hypometabolism involving occipital region were found. The dopamine transporter levels derived from TRODAT-1 scan had excellent discrimination in diagnosing DLB compared with age-matched normal controls (1.58 [0.2] and 1.84 [0.1], P < 0.01) but without significant differences between mild and dementia stages. The sophisticated cortical-brainstem networks by FDG PET and TRODAT-1 yielded good clinical correlation. Conclusions The networks yielded from FDG PET and TRODAT-1 revealed good correlation with clinical data and that nigrostriatal pathway abnormalities are preceded by typical occipital hypometabolism in mild stage of DLB. Dopamine transporter levels may serve as early diagnostic tool and FDG PET as staging indicator for DLB pathology.

Detection of gray matter damage using brain MRI and SPECT in carbon monoxide intoxication: a comparison study with neuropsychological correlation.

Purpose While lesion patterns in white matter have been extensively reported in the literature on carbon monoxide (CO) intoxication, reports on the effects on gray matter damage are less common. The aim of this study was to investigate regional damage patterns focusing on gray matter using 99mTc ethyl cysteinate dimer (ECD) brain single photon emission computed tomography (SPECT) and brain magnetic resonance imaging (MRI) with clinical correlation. Patients and Methods Thirty CO intoxication patients and 15 age-matched controls were enrolled for standard neuropsychological tests. Six regions of interest (ROI) were analyzed qualitatively and quantitatively in both SPECT and MRI. The patients were further grouped according to clinical dementia rating score. The sensitivity, specificity, and positive and negative predictive ratios related to dementia from both imaging modalities were further examined. Results In SPECT qualitative analysis, basal ganglia (n = 16) were the most common regions showing lower perfusion patterns. The basal ganglion and temporal, frontal, and parietal regions of the patients with dementia showed significantly lower perfusion patterns. MRI had a higher sensitivity while SPECT had a higher specificity and positive and negative predictive ratios in correlation with dementia among the ROI. The perfusion indices of the frontal, temporal, basal ganglion, and thalamus were inversely correlated with clinical severity (all P < 0.05). Conclusions Our findings suggest that a multiparametric neuroimaging approach may provide more information in revealing the anatomical and neurobehavioral results in patients after CO intoxication. The atrophy pattern seen in MRI may explain in part the possible mechanism of the hypoperfusion state seen in SPECT.

Tc99m-sestamibi thigh SPECT/CT images for noninvasive assessment of skeletal muscle injury in carbon monoxide intoxication with clinical and pathological correlation.

Purpose: Muscle weakness has been repeatedly reported in patients with carbon monoxide (CO) intoxication. In animal models, CO intoxication has been linked with mitochondrial electron transport dysfunction. The objectives of the present study were to use Tc-99m sestamibi thigh single-photon emission computed tomography/computed tomography (SPECT/CT) to evaluate the mitochondrial status in patients with CO intoxication, correlate this with clinical parameters, and compare with age-matched controls. Material and Methods: A total of 25 patients with delayed sequelae after CO intoxication (range: 1–60 months) and 17 sex- and age-matched healthy volunteers underwent Tc-99m sestamibi thigh SPECT/CT. Cognitive evaluation and muscle power according to medical research council (MRC) grading were collected. Both visual scoring from planar images and automatic volumetric analysis were used to rate the Tc-99m sestamibi uptake level. Results: The visual scores showed that 14 patients (56.0%) were scored as moderate-to-severe decrement. Volumetric analysis showed that a significant Tc99m-sestamibi uptake decrement was found in the CO intoxication group as compared with the controls, and 16 patients (64.0%) had uptakes below 1 standard deviation of the control group. In the CO group, the muscle power but not the cognitive evaluation correlated with Tc-99m sestamibi uptake in muscles. The decrement of muscle Tc99m-sestamibi uptake was related to mitochondria swelling, increased mitochondrial numbers, and type II muscle atrophy in 1 patient. Conclusions: In this study, we demonstrated that patients with CO intoxication sustained defective mitochondrial metabolism in skeletal muscles as revealed by a decrement in Tc-99m sestamibi uptake either by visual or semiquantification of thigh SPECT/CT. Tc-99m sestamibi scanning provided noninvasive measurement of mitochondrial injury in muscles after CO intoxication and the correlation with clinical parameters was good.

Central nervous system involvement in hepatocellular carcinoma: clinical characteristics and comparison of intracranial and spinal metastatic groups.

From January 1993 to December 2006 we analyzed the clinical characteristics of patients with hepatocellular carcinoma (HCC) with central nervous system (CNS) metastasis at the Kaohsiung Chang Gung Memorial Hospital, Taiwan. Forty-six patients with HCC and CNS metastasis were identified, of whom 36 had intracranial metastasis and 10 had spinal metastasis. The clinical presentations, laboratory data and imaging studies were collected and analyzed. The age at the time of HCC diagnosis ranged from 34 to 78 years; CNS metastasis occurred between 0 and 85 months after diagnosis and death followed between 0 and 93 months later. The Glasgow Coma Scale (GCS) score at the time of CNS metastasis ranged from 7 to 15 and the Child-Pugh score at diagnosis of HCC ranged from 5 to 15. Patients with spinal metastasis had a higher GCS score and lower Child-Pugh score at diagnosis. None of the serum biochemical studies showed unique abnormalities. From the data currently available, intracranial metastasis is the most common site of CNS metastasis of HCC. Advances in treating and diagnosing HCC have improved patient outcomes remarkably; however, CNS metastasis continues to have a grave prognosis. Without a specific biomarker for predicting CNS involvement in HCC, a high index of suspicion for the diagnosis should be maintained, particularly in HCC hyperendemic areas such as Taiwan.

99mTc-sestamibi thigh SPECT/CT imaging for assessment of myopathy in cerebrotendinous xanthomatosis with histopathological and immunohistochemical correlation.

Purpose The aim of this study was to determine the effectiveness of using 99mTc-sestamibi thigh SPECT/CT imaging for evaluating myopathy in cerebrotendinous xanthomatosis (CTX). Patients and Methods Four genetically proven CTX patients (Family I, Cases I-1 and I-2; Family II, Cases II-1 and II-2) were included. They all underwent muscle biopsies for histopathologic and ultrastructural studies. Immunohistochemical staining for vinculin expression was also performed. 99mTc-sestamibi thigh SPECT/CT imaging was conducted on all 4 CTX patients, and both visual interpretation and muscle-to-background (M/B) ratio count were applied for assessment. Correlation analysis of the imaging findings and results of the ultrastructural and immunohistochemical studies was done. Results In the 99mTc-sestamibi thigh SPECT/CT imaging study, all 4 CTX cases had abnormal scores of visual interpretation and M/B ratios. The ultrastructural features of the skeletal muscle of the 4 CTX cases showed mitochondrial and membrane system abnormalities, with increased depositions of metabolites. They also had abnormal increases in vinculin expression after immunohistochemical staining of the skeletal muscle. Conclusions This is the first report on the use of 99mTc-sestamibi thigh SPECT/CT imaging to assess the mitochondrial status of CTX. The imaging findings may have a correlation with the ultrastructural and immunohistochemical findings on skeletal muscle. Although the 99mTc-sestamibi thigh SPECT/CT imaging is not specific for CTX, this noninvasive in vivo assessment can be an important tool for the detection and follow-up study of skeletal muscle involvement in CTX.