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Background Plasma glial fibrillary acidic protein (GFAP) has emerged as a promising biomarker in neurological disorders, but further evidence is required in relation to its usefulness for diagnosis and prediction of Alzheimer disease (AD). Methods Plasma GFAP was measured in participants with AD, non-AD neurodegenerative disorders, and controls. Its diagnostic and predictive value were analyzed alone or combined with other indicators. Results A total of 818 participants were recruited (210 followed). Plasma GFAP was significantly higher in AD than in non-AD dementia and non-demented individuals. It increased in a stepwise pattern from preclinical AD, through prodromal AD to AD dementia. It effectively distinguished AD from controls [area under the curve (AUC) > 0.97] and non-AD dementia (AUC > 0.80) and distinguished preclinical (AUC > 0.89) and prodromal AD (AUC > 0.85) from Aβ-normal controls. Adjusted or combined with other indicators, higher levels of plasma GFAP displayed predictive value for risk of AD progression (adjusted hazard radio= 4.49, 95%CI, 1.18–16.97, P = 0.027 based on the comparison of those above vs below average at baseline) and cognitive decline (standard-β=0.34, P = 0.002). Additionally, it strongly correlated with AD-related cerebrospinal fluid (CSF)/neuroimaging markers. Conclusions Plasma GFAP effectively distinguished AD dementia from multiple neurodegenerative diseases, gradually increased across the AD continuum, predicted the individual risk of AD progression, and strongly correlated with AD CSF/neuroimaging biomarkers. Plasma GFAP could serve as both a diagnostic and predictive biomarker for AD.

Background and ObjectivesTo investigate the relationship between baseline structural measurements of brain reserve and clinical progression in Parkinson disease (PD). To further provide a possible underlying mechanism for structural measurements of brain reserve in PD, we combined functional and transcriptional data and investigated their relationship with progression-associated patterns derived from structural measurements and longitudinal clinical scores.MethodsThis longitudinal study collected data from June 2010 to March 2019 from 2 datasets. The Parkinson's Progression Markers Initiative (PPMI) included controls and patients with newly diagnosed PD from 24 participating sites worldwide. Results were confirmed using data from the Huashan dataset (Shanghai, China), which included controls and patients with PD. Clinical symptoms were assessed with Movement Disorder Society–sponsored revision of the Unified Parkinson's Disease Rating Scale (MDS-UPDRS) scores and Schwab & England activities of daily living (ADL). Both datasets were followed up to 5 years. Linear mixed-effects (LME) models were performed to examine whether changes in clinical scores over time differed as a function of brain structural measurements at baseline.ResultsA total of 389 patients with PD (n = 346, age 61.3 ± 10.03, 35% female, PPMI dataset; n = 43, age 59.4 ± 7.3, 38.7% female, Huashan dataset) with T1-MRI and follow-up clinical assessments were included in this study. Results of LME models revealed significant interactions between baseline structural measurements of subcortical regions and time on longitudinal deterioration of clinical scores (MDS-UPDRS Part II, absolute β > 0.27; total MDS-UPDRS scores, absolute β > 1.05; postural instability–gait difficulty (PIGD) score, absolute β > 0.03; Schwab & England ADL, absolute β > 0.59; all p < 0.05, false discovery rate corrected). The interaction of baseline structural measurements of subcortical regions and time on longitudinal deterioration of the PIGD score was replicated using data from Huashan Hospital. Furthermore, the β-coefficients of these interactions recapitulated the spatial distribution of dopaminergic, metabolic, and structural changes between patients with PD and normal controls and the spatial distribution of expression of the α-synuclein gene (SNCA).DiscussionPatients with PD with greater brain resources (that is, higher deformation-based morphometry values) had greater compensatory capacity, which was associated with slower rates of clinical progression. This knowledge could be used to stratify and monitor patients for clinical trials.

Background According to the new ‘AT(N)’ system, those with a normal amyloid biomarker but with abnormal tauopathy or biomarkers of neurodegeneration or neuronal injury, have been labeled suspected non-Alzheimer’s pathophysiology (SNAP). We aimed to estimate the long-term clinical and cognitive trajectories of SNAP individuals in non-demented elders and its comparison with individual in the Alzheimer’s disease (AD) pathophysiology using ‘AT(N)’ system. Methods We included individuals with available baseline cerebrospinal fluid (CSF) Aβ (A), CSF phosphorylated tau examination (T) and 18F-fluorodeoxyglucose PET or volumetric magnetic resonance imaging (N) from the Alzheimer's Disease Neuroimaging Initiative database. Longitudinal change in clinical outcomes are assessed using linear mixed effects models. Conversion risk from cognitively normal (CN) to cognitively impairment, and conversion from mild cognitive impairment (MCI) to dementia are assessed using multivariate Cox proportional hazard models. Results Totally, 366 SNAP individuals were included (114 A-T-N-, 154 A-T + N-, 54 A-T-N + and 44 A-T + N+) of whom 178 were CN and 188 were MCI. Compared with A-T-N-, CN elders with A-T + N-, A-T-N + and A-T + N + had a faster rate of ADNI-MEM score decline. Moreover, CN older individuals with A-T + N + also had a faster rate of decline in ADNI-MEM score than those with A-T + N- individuals. MCI patients with A-T + N + had a faster rate of ADNI-MEM and ADNI-EF decline and hippocampal volume loss compared with A-T-N- and A-T + N- profiles. CN older individuals with A-T + N + had an increased risk of conversion to cognitive impairment (CDR-GS ≥ 0.5) compared with A-T + N- and A-T-N-. In MCI patients, A-T + N + also had an increased risk of conversion to dementia compared with A-T + N- and A-T-N-. Compared with A-T + N-, CN elders and MCI patients with A + T + N- and A + T + N + had a faster rate of ADNI-MEM score, ADNI-EF score decline, and hippocampal volume loss. CN individuals with A + T + N + had a faster rate of ADNI-EF score decline compare with A-T + N + individuals. Moreover, MCI patients with A + T + N + also had a faster rate of decline in ADNI-MEM score, ADNI-EF score and hippocampal volume loss than those with A-T + N + individuals. Conclusions The findings from clinical, imaging and biomarker studies on SNAP, and its comparison with AD pathophysiology offered an important foundation for future studies.

Purpose TSPO PET with radioligand 18F-DPA714 is an emerging molecular imaging technique that reflects cerebral microglial activation and has been recently used in central nervous system diseases. In this study, we aimed to investigate the microglial activation pattern of anti–leucine-rich glioma-inactivated 1 (LGI1) protein autoimmune encephalitis (AIE) and to evaluate its correlation with clinical phenotypes. Methods Twenty patients with anti-LGI1 encephalitis from the autoimmune encephalitis cohort in Huashan hospital and ten with other AIE and non-inflammatory diseases underwent TSPO PET imaging were included in the current study. TSPO PET abnormalities in anti-LGI1 AIE were detected on a voxel basis using statistic parametric mapping analysis. Multiple correspondence analysis and hierarchical clustering were conducted for discriminate subgroups in anti-LGI1 AIE. Standardized uptake value ratios normalized to the cerebellum (SUVRc) were calculated for semiquantitative analysis of TSPO PET features between different LGI1-AIE subgroups. Results Increased distribution of 18F-DPA714 was identified in the bilateral hippocampus, caudate nucleus and frontal cortex in anti-LGI1 patients. Two subgroups of anti-LGI1 patients were distinguished based on the top seven common symptoms. Patients in cluster 1 had a high frequency of facio-brachial dystonic seizures than those in cluster 2 (p = 0.004), whereas patients in cluster 2 had a higher frequency of general tonic clonic seizures than those in cluster 1 (p < 0.001). Supplementary motor area and superior frontal gyrus showed higher 18F-DPA714 distribution in cluster 2 patients compared with those in cluster 1 (p = 0.024; p = 0.04, respectively). Conclusions Anti-LGI1 AIE has a distinctive molecular imaging pattern presented by TSPO PET scan. Different characteristics in LGI1-AIE subgroups indicate underlying mechanisms of microglia in pathogenesis and clinical phenotypes. Further studies are required for verifying its value in clinical application.

Previous studies with a limited sample size suggested more severe dopaminergic transporter (DAT) lesions in the striatum of progressive supranuclear palsy (PSP) than those in Parkinson's disease (PD) and multiple system atrophy-parkinsonism (MSA-P). However, few studies had taken various subtypes of PSP into consideration, making the reanalysis of DAT imaging in larger PSP cohort with various subtypes in need.To compare the dopaminergic lesion patterns of PSP with MSA-P and PD, and to explore the specific striatal subregional patterns of different PSP subtypes.The patients with PSP presented more severe DAT loss in the striatum than in PD and MSA-P, especially in caudate. In PSP, the subregional lesion was still more severe in putamen than in caudate, similar to that in PD and MSA-P. Among detailed subtypes, no significant difference was detected.The dopaminergic lesions were more severe in PSP, and no difference was detected among subtypes.

Background Pathogenic mutations in the TANK-binding kinase 1 (TBK1) gene have been associated with progressive supranuclear palsy (PSP)-like extrapyramidal symptoms, amyotrophic lateral sclerosis (ALS), as well as cognitive and behavioral alterations. However, the question as to whether TBK1 mutations may be associated with tau burden remains unanswered. Methods To investigate whether patients presenting with PSP-like extrapyramidal symptoms caused by TBK1 mutations have evidence of tau deposition as reflected by positive 18F-APN-1607 tau PET imaging findings. Four patients who showed PSP-like extrapyramidal symptoms, ALS, and cognitive/behavioral alterations were consecutively enrolled between August 2019 and August 2020. Patients underwent TBK1 gene sequencing and 18F-APN-1607 tau PET imaging. All PET images were interpreted in a blinded fashion with respect to genetic results. Brain structural changes were investigated with MRI, whereas 11C-CFT or 18F-DTBZ PET imaging was performed to identify dopaminergic degeneration. Results Pathogenic TBK1 mutations were identified in three of the four study patients. The three mutation carriers – but not the case without – showed positive 18F-APN-1607 binding in PSP-related regions, suggesting the presence of tau pathology. Mesencephalic atrophy (hummingbird sign) was observed in all TBK1 mutation carriers, and two of them also had evidence of frontotemporal atrophy. Dopaminergic degeneration was evident in all cases, regardless of TBK1 mutations. Conclusions Pathogenic TBK1 mutations in patients with PSP-like extrapyramidal symptoms are associated with positive 18F-APN-1607 tau PET imaging findings. Our data should prompt additional investigations on the potential role of tau accumulation in the pathogenesis of disease conditions associated with TBK1 mutations.

Frontotemporal lobar degeneration with tauopathy caused by MAPT (microtubule-associated protein tau) mutations is a highly heterogenous disorder. The ability to visualize and longitudinally monitor tau deposits may be beneficial to understand disease pathophysiology and predict clinical trajectories.The aim of this study was to investigate the cross-sectional and longitudinalSeven carriers of MAPT mutations (six within exon 10 and one outside of exon 10) and 15 healthy control subjects were included. All participants underwentAlthough the seven study patients had heterogenous clinical phenotypes, all showed a significantOur data represent a promising step in understanding the usefulness of

Additional file 1.

Supplemental material, 03_Supplementary_Material_20180929 for Preserved caudate function in young-onset patients with Parkinson’s disease: a dual-tracer PET imaging study by Yu-jie Yang, Jing-jie Ge, Feng-tao Liu, Zhen-yang Liu, Jue Zhao, Jian-jun Wu, Yilong Ma, Chuan-tao Zuo and Jian Wang in Therapeutic Advances in Neurological Disorders

This study aimed to characterize the clinical features and the related cerebral glucose metabolism pattern of cognitive impairments in Parkinson's disease (PD) with positron emission tomography (PET) imaging. We recruited 168 PD patients and 100 age‐matched healthy controls of similar education and gender distribution. All of those enrolled underwent clinical assessment including the unified Parkinson's disease rating scale motor score, Hoehn and Yahr scale, and comprehensive neuropsychological tests including domains of executive function, attention, memory, visuospatial function, and language. Demographics and the results of cognitive measures were compared between patients and healthy controls. Cognition status was classified as PD patients with dementia (PD‐D), PD patients with mild cognitive impairment (PD‐MCI), or PD patients with normal cognition (PD‐NC). In 53 PD patients who underwent (18)F‐fluorodeoxyglucose ((18)F‐FDG) PET imaging, correlations between Z‐score values of the different cognitive domains and cerebral (18)F‐FDG uptake were assessed using statistical parametric mapping (SPM8) corrected for age and motor severity. A total of 23.2% of PD patients were PD‐MCI and 8.9% were PD‐D. In the group of PD‐MCI, 96.3% showed multiple‐domain deficits, with executive function and attention impairment most predominantly involved. All the cognitive domain scores with the exception of language correlated with (18)F‐FDG metabolisms, primarily in posterior temporo‐parieto‐occipital association cortical areas. This study found that cognitive impairment in PD particularly encompasses frontal/executive deficits. Posterior cortical areas, containing multiple neurotransmitters and neural circuits, may play an important role in the pathogenesis of cognitive impairment in PD.

Objectives By observing and evaluating the clinical curative effect systematically of electrical acupuncture (EA) on Tianshu (ST 25) on diarrhea-predominant irritable bowel syndrome (D-IBS), to make it benefit for the application and spread of EA on Tianshu (ST 25) on D-IBS.

Background A number of hereditary neurological diseases display indistinguishable features at the early disease stage. Parkinsonian symptoms can be found in numerous diseases, making it difficult to get a definitive early diagnosis of primary causes for patients with onset of parkinsonism. The accurate and early diagnosis of the causes of parkinsonian patients is important for effective treatments of these patients. Methods We have identified a Chinese family (82 family members over four generations with 21 affected individuals) that manifested the characterized symptoms of parkinsonism and was initially diagnosed as Parkinson’s disease. We followed up with the family for two years, during which we carried out clinical observations, Positron Emission Tomography-Computed Tomography neuroimaging analysis, and exome sequencing to correctly diagnose the case. Results During the two-year follow-up period, we performed comprehensive medical history collection, physical examination, and structural and functional neuroimaging studies of this Chinese family. We found that the patient exhibited progressive deteriorated parkinsonism with Parkinson disease-like neuropathology and also had a good response to the initial levodopa treatment. However, exome sequencing identified a missense mutation, N279K, in exon 10 of MAPT gene, verifying that the early parkinsonian symptoms in this family are caused by the genetic mutation for hereditary frontotemporal lobar dementia. Conclusions For the inherited parkinsonian patients who even show the neuropathology similar to that in Parkinson’s disease and have initial response to levodopa treatment, genetic identification of the molecular basis for the disease is still required for defining the early diagnosis and correct treatment.

Background: Deafferentation pain secondary to brachial plexus avulsion, spinal cord injury, and other peripheral nerve injuries is often refractory to conventional treatments. Stimulation of the primary motor cortex (M1) has been proven to be an effective treatment for intractable deafferentation pain. The mechanisms underlying the attenuation of deafferentation pain by motor cortex stimulation remain hypothetical. Objectives: The purpose of this case report is to: (1) summarize a case in which a patient suffering chronic intractable deafferentation pain for 25 years underwent rTMS treatment over M1, (2) describe the evidence from PET imaging, and (3) reveal a possible relief mechanism with cortical plasticity. Study design: Case report. Setting: University hospital. Results: This patient had successful pain control with no transient or lasting side effects. The pain relief remained stable for at least one week. At the end of the 20-day procedure, pain relief was obtained according to the Visual Analog Scale (VAS) (-34.6%) and the McGill Pain Questionnaire (MPQ) (-31.6%). In the PET/CT scans, the glucose metabolism was significantly reduced contralaterally to the pain side in the anterior cingulate cortex (ACC), insula, and caudate nucleus. There was no statistically significant difference in any other cortical area. Limitations: Single case of a patient with long-term intractable deafferentation pain having a PET study. Conclusion: This study implies that a single session of 20 Hz rTMS over the motor cortex could reduce the pain level in patients suffering from long-term, intractable deafferentation pain. The stimulation of the M1 induces deactivation in the ACC, insula, and caudate nucleus. The changes in these pain-related regions may mirror an adaptive mechanism to pain relief after rTMS treatment. Key words: Neuropathic pain management, deafferentation pain, transcranial magnetic stimulation, motor cortex stimulation, cortical plasticity, positron emission tomography

To study the influence of the audio-visual block (AB) on the brain glucose metabolism of idiopathic tinnitus patients.The brain positron emission tomography (PET) test was performed on one chronic idiopathic tinnitus patient under audio-visual block and non-block (NB) conditions respectively. The visual analysis and statistical parameter mapping (SPM) analysis were both used to detect the brain glucose metabolism difference under AB and NB conditions.Under NB conditions, significant hyperactivity was detected at auditory and visual cortex on both sides of the brain. However, this phenomenon was not shown under AB conditions. Instead, a hyperactivity of brain was presented in the left Wernicke's area.The generation of chronic idiopathic tinnitus probably has no relationship with the auditory cortex abnormity. Wernicke's area might be involved in the central perception of tinnitus.

Department of Hand Surgery, Huashan Hospital, Fudan University, 12 Wulumuqi Middle Road, Shanghai 200040, China Department of Radiology, Huashan Hospital, Fudan University, 12 Wulumuqi Middle Road, Shanghai 200040, China PET Center, Huashan Hospital, Fudan University, 12 Wulumuqi Middle Road, Shanghai 200040, China State Key Laboratory of Medical Neuroscience, Fudan University, 138, Yi Xue Road, Shanghai 200032, China

Peripheral nerve injury in a limb usually causes intrahemispheric functional reorganization of the contralateral motor cortex. Recently, evidence has been emerging for significant interhemispheric cortical plasticity in humans, mostly from studies of direct cortical damage. However, in this study, a long-range interhemispheric plasticity was demonstrated in adults with brachial plexus avulsion injury (BPAI) who had received a contralateral cervical nerve transfer, and this plasticity reversed the BPAI-induced intrahemispheric cortical reorganization.In this study, 8 adult male patients with BPAI were studied using PET scanning.The results indicated that the right somatomotor cortices, which may contribute to the control of the injured limb before brachial plexus deafferentation, still played an important role when patients with BPAI tried to move their affected limbs, despite the fact that the contralateral C-7 nerve transfer had been performed and the peripheral output had changed dramatically. Such findings are consistent with the results of the authors' previous animal study.The brain may try to restore the control of an injured limb to its original cortex area, and a complicated change of peripheral pathway also can induce long-range interhemispheric cortical reorganization in human motor cortex.

The objective of this study was to evaluate the incidence of incidental parotid masses with conventional whole-body ¹⁸F-deoxyglucose (FDG) PET/CT and assess the ability of PET/CT to characterize these unexpected parotid lesions.Fifty eight incidental findings of parotid masses with routine FDG PET/CT whole-body scan were reviewed in this retrospective analysis, which were selected from the patients without any known or suspected parotid disease in our PET center, from June 2005 to May 2009. 51 cases were operated or underwent a biopsy after a short-term PET/CT study; the remaining 7 cases had a follow-up. Parotid mass that showed both noncontrast CT (irregular shape and blurry border) and PET malignant features (high FDG uptake, SUV(max)3.0) was considered as positive for malignancy. Correlation of FDG PET/CT with histology or follow-up outcome was performed.Fifty eight unexpected findings of parotid masses accounted for 0.3% of the total cases in 4 years, including 11 (19.0%) malignant tumors and 47 (81.0%) benign lesions. 13 lesions manifested single nodule with malignant CT features and intense FDG activity, of which 6 were proved to be malignant; thus, sensitivity and positive predictive values were 54.5% (6 of 11) and 46.2% (6 of 13), respectively. 45 lesions showed either single nodule with benign CT features, or a low FDG uptake (SUV(max) ≤ 3.0), of which 40 were true negatives; therefore, specificity and negative predictive values were 85.1% (40 of 47) and 88.9% (40 of 45), respectively. All parotid masses except 9 benign and 1 malignant showed a high FDG uptake. Compared with SUV only, combined interpretation of PET and CT results displayed a lower sensitivity (90.9-54.5%), but a higher specificity (19.1-85.1%) and a higher overall accuracy.Whole-body FDG-PET/CT at the time of surveying the entire body condition is helpful for detecting the asymptomatic parotid masses. Combined noncontrast CT is an essential evidence for improving the diagnostic accuracy of FDG-PET/CT for parotid masses.

This retrospective study evaluated the diagnostic accuracy of 2-(F18)-fluoro-2-deoxy-D-glucose-positron emission tomography ((18)F-FDG-PET)/computed tomography (PET/CT) in the preoperative diagnosis of metastatic mediastinal and hilar lymph node in patients with non-small-cell lung cancer (NSCLC).A total of 39 patients received preoperative (18)F-FDG PET/CT and the postoperative biopsy. We compared preoperative PET/CT scan results with corresponding intraoperative histopathalogic findings in 39 NSCLC patients. The sensitivity, specificity, accuracy, positive and negative predictive value of (18)F-FDG PET/CT were assessed.Histopathologic examination confirmed metastasis in 57 out of the 208 excised lymph nodes; 23 of the 57 nodes were mediastinal and hilar lymph nodes. The sensitivity, specificity, accuracy, positive predictive value and negative predictive value of PET/CT in the preoperative diagnosis of mediastinal lymph node metastasis in NSCLC patients were 65%, 96.8%, 92%, 78.5% and 90%, respectively.PET/CT scan showed good accuracy in the preoperative diagnosis of mediastinal and hilar lymph node metastasis in the patients with NSCLC. We recommend that PET/CT scanning be used as a first-line evaluation tool for tumor diagnosis, therapy evaluation and follow-up.

This study aimed to evaluate the prognostic value of 2-[18F]fluoro-2-deoxy-D-glucose (18F-FDG) uptake determined by positron emission tomography (PET) in patients with non-small cell lung cancer (NSCLC) in relation to disease stage and/or tumor histology. A retrospective review of 144 patients with newly diagnosed lung cancer undergoing PET imaging was performed. Differences in survival were compared by univariate and multivariate analyses. Univariate analysis identified three prognostic factors: stage, lesion size and the standardized 18F-FDG uptake value. The latter was a better prognostic predictor in lung cancer patients with early-stage disease than in those at advanced stages. Multivariate analysis revealed that the most important prognostic factors were tumor-node-metastasis (TNM) stage and the standardized 18F-FDG uptake value. Patients with standardized uptake values (SUVs) >8 had a 2.5 times higher mortality rate than those with values ≤8. A one-unit increase in SUV corresponded with a 7% increase in the hazard of death. SUVs provided stronger prognostic stratification in patients with adenocarcinoma than in those with squamous cell carcinoma (SCC). Furthermore, the best choice of prognostic predictor differed between the two types of lung cancer: the SUV was best for SCC, while TNM stage was most significant for adenocarcinoma. In conclusion, 18F-FDG uptake in primary lung lesions is an independent prognostic predictor in patients with NSCLC, especially those with adenocarcinoma or early-stage disease. Further stratification of patients with the same TNM stage based on SUVs may allow for the modification of individual treatment strategies, resulting in improved outcome.

The scholars at home and abroad pay great attention to the studies of specificities of acupoints, but the studies were superficial and non-systemic because of lacking to application of modern sciences and technology. There are not persuasive conclusive achievements for the specificities of acupoints and the key factors influencing the effect of acupuncture. The study of the specificities of acupoints should be concentrate on the diseases for which acupuncture and moxibustion are effective. And multiple modern sciences and techniques should be adopted to resolve the key problems about biological and physical characteristics, pathological response, effects and law of compatibility of acupoints usually selected for the diseases, and then to create the model of the theory about the specificities of acupoints and to richen and develop the theory of the specificity of acupoints.

To investigate the FDG uptake characteristics, the factors affecting 18F-FDG uptake and the extra CT diagnostic value of 18F-FDG PET/CT scan in the malignant tumor with false negative 18F-FDG PET image.The data of PET/CT image in 17 patients with various kinds of cancers were reviewed and analyzed by visual observation and semi-quantity analysis ( SUV). The results were compared with the CT and histopathological diagnosis, respectively.Of 6 well-differentiated HCC patients confirmed by histopathological diagnosis, one had two lesions in the right lobe of the liver. One of these two lesions showed low FDG uptake on 18F-FDG PET scan and low density on CT scan. The other one was not shown on either 18F-FDG PET or plain CT scan. But on enhanced CT scan, these two lesions were found to be inhomogeneous with high density at arterial phase. The false negative 18F-FDG PET images of one gastric signet ring cell carcinoma in the gastric fundus with right adnexa metastasis, 3 renal cell carcinoma, one greater omentum and peritoneal metastatic adenocarcinoma and one well-differentiated prostate cancer were caused by normal physical uptake in the digestive tract or FDG retention in the urinary system due to normal excretion. The size of three metastases was smaller than or equal to 1 cm in diameter, however, two primary lesions of these metastases showed high FDG uptake and only one was negative on either 18F-FDG PET or CT scan. In this series, 68.8% of the primary tumors and 66.7% of metastases were found to show abnormal density on CT scan, and 31. 2% of the primary tumors and 33. 3% of metastases were not detectable on either PET or CT images.False negative 18F-FDG PET in malignant tumor may be correlated with the pathologic type, differentiation degree and the lesion size. Combining CT information with PET or paying attention to the scan methods during 8 F-FDG PET examination may reduce the rate of false negative 18F-FDG PET diagnosis in various kinds of malignant tumors.

To measure the changes of regional cerebral metabolism rate of glucose (rCMRglc) in patients with Alzheimer's disease (AD) and explore their value to diagnosis of AD.10 patients with AD who met the diagnostic criteria of DSM-IV and 10 normal controls (NC) were assessed with (18)F-2-fluoro-deoxy-D-glucose positron emission tomography (PET).The two groups were matched in age, gender and education. The mean total scores of the mini-mental status examination (MMSE) were 16.5 +/- 6.1 for AD and 28.7 +/- 1.6 for NC. The mean total memory quotient of Wechsler Memory Scales (MQ) were 32.3 +/- 19.6 for AD and 93.1 +/- 9.0 for NC. Comparing to NC, the AD groups showed statistically significant decline of rCMRglc in frontal lobe, temporal lobe and the hippocampal formation with decreased rates ranged from 3.3% to 28.4% (P0.05, P0.01). The hypo-metabolism was more salient in the regions of upper and middle frontal gyri, middle temporal gyrus, orbital gyrus and anterior cingulate gyrus, in which areas the metabolism decreased over 20% compared to NC. The hypo-metabolism was correlated to the severity of dementia. Discriminant analysis demonstrated that the variables of right inferior temporal gyrus, left upper temporal gyrus, left hippocampus and right insular lobe were entered into the discriminant functions and the total discriminant accuracy reached 100%.(18)F-FDG PET is a very sensitive tool in measurement of the changes of rCMRglc in patients with AD. The findings show a frontal-temporal type of metabolism in AD patients and suggest that hypo-metabolism in hippocampal formation and temporal lobe is helpful in early detection of AD.

Local relapse,tumor residue, and whole body metastases of nasopharyngeal carcinoma (NPC) after radiotherapy were mainly confirmed by CT, MRI, SPE/CT, and PET examinations. This study was to discuss the value of F-18-fluoro-2-deoxy-d-glucose positron emission tomography/computed tomography (PET/CT) in detecting suspected recurrence or tumor residue, and whole body metastases of NPC after radiotherapy.PET/CT were performed on 38 NPC patients 3-36 months after radiotherapy. The images of PET/CT, CT, and PET were observed. PET standardized uptake value (SUV) was calculated, and SUV of2.5 was considered as positive. The Patients were divided into 4 groups by diagnosis: (1) no recurrence/residue, and no whole body metastases; (2) with recurrence/residue, but no whole body metastases; (3) no recurrence/residue, but with whole body metastases; (4) with both recurrence/residue and whole body metastases. Diagnoses of all patients were referred to the proved follow-up clinical information. The following-up time was 6-10 months.The sensitivity, and specificity of PET/CT (100%,and 89.5%) were better than that of CT alone (77.8%, and 84.2%), a litter better than that of PET alone (100%, and 80.0%).FDG-PET scan is a better tool than CT alone for the detection of recurrene or residue, and whole body metastases of NPC, a litter better than PET alone. PET/CT may provide valuable information for judging whether the focus is metastasis.

To study the different effect of needling at different meridian points (MP) on different cerebral functional regions by using positron emission tomography and cerebral function tracer 18F-fluorodeoxy glucose to observe the effect of electro-acupuncture (EA) stimulation at Yin MP or Yang MP on local cerebral glucose metabolism in 30 healthy volunteers.The thirty subjects were randomly divided into 2 groups, the 12 subjects in the Yang MP group treated by needling at Hegu (LI4), Quchi (LI11), Zusanli (St36) and Shangjuxu (St37), the 18 subjects in the Yin MP group treated by needling at Neiguan (Pc6), Chize (Lu5), Sanyinjiao (Sp6) and Yinlingquan (Sp9). All the needling was conducted at one side of body.After needling at Yang MP, the cerebral glucose metabolism was elevated in bilateral cross region of frontal lobe and temporal lobe, parietal lobe, thalamus and basal ganglia, and in contralateral cerebellum and hippocampus. After needling at Yin MP, the cerebral glucose metabolism was lowered in bilateral cross region of frontal and temporal lobe, contralateral temporal lobe, cerebellum and thalamus, and was elevated in homolateral hippocampus and caudate nucleus.Under physiological condition, the regulatory effects of acupuncture on central nervous system would be different when needling at different MP.