18F-氟脱氧葡萄糖PET/CT在胰腺癌放疗中的应用

18F-氟脱氧葡萄糖PET/CT在胰腺癌的放疗中具有重要的应用价值。PET/CT较常规影像学检查能提高胰腺癌放疗前的诊断及分期准确性。在放疗过程中,以PET/CT检查为基础的靶区勾画能够准确地覆盖肿瘤组织及保护周围正常组织,同时可以按照其所提示的肿瘤代谢活性调整放疗计划。PET/CT还能够进行放疗的疗效评估及预后评判。相信随着研究的进展,18F-氟脱氧葡萄糖PET/CT将在胰腺癌放疗中发挥越来越重要的作用。     

耳鸣相关脑区改变PET/CT脑代谢及灌注显像的初步研究

目的：研究耳鸣相关脑区的代谢及血流灌注变化,确定主观性耳鸣与神经中枢的对应关系。方法应用18F-FDG/13N-NH3·H2O PET/CT脑显像,采用ROI技术对43例耳鸣患者及40名健康对照者的显像结果进行分析。结果18F-FDG PET/CT显像单侧葡萄糖代谢增高者共24例、32个脑区;左侧特定的脑区位于颞上回、颞中回、缘上回等;右侧特定的脑区位于颞上回、颞中回等。其中有24个（75%）区域伴血流灌注增高。18F-FDG PET/CT显像双侧葡萄糖代谢增高者共10例,左、右各10个脑区,非对称性分布,其中有18个（90%）区域伴血流灌注增高。5例耳鸣患者代谢低于正常,特定脑区位于右侧颞上回、颞中回,相应脑区血流灌注低于正常。18F-FDG及13N-NH3·H2O PET/CT显像脑区代谢及灌注改变与耳鸣的侧别无关。结论主观性耳鸣患者相关脑区的改变较广泛而不仅局限于听中枢,以糖代谢和血流灌注增高为主要表现,与耳鸣侧别无关;脑区葡萄糖代谢与脑血流灌注改变基本一致。     

18F-FDG PET/CT与18F-FDG PET/MRI在卵巢癌临床应用中的进展

卵巢癌是妇科恶性肿瘤中病死率最高的肿瘤。18F-FDG PET/CT在卵巢癌的诊断、分期、疗效及预后的评估上优于常规影像技术,可以指导临床采取有针对性的治疗方案,以获得更好的治疗效果。PET/MRI是最近几年继PET/CT后投入临床应用的另外一种多模态影像技术,因其多序列成像、软组织分辨率较高和辐射剂量较低,对卵巢癌的诊治具有独特的优势。笔者对18F-FDG PET/CT和18F-FDG PET/MRI在卵巢癌中的临床应用进行综述。     

中晚期食道癌PET/CT代谢体积变化与临床效果相关性研究

目的前瞻性探讨治疗前、中和治疗后采用PET/CT确定的同步放化疗中晚期食道癌原发肿瘤代谢体积(PTMV)的变化与预后的关系。方法2012年9月~2017年6月38例中晚期食道癌行放化疗患者,在治疗前、放疗后第3~4周、治疗后第6周行PET/CT检查。利用ROC寻找治疗前、中和治疗后PTMV的变化的最佳界值,将其分为高、低值组。Kaplan-Meier法生存分析并Log-rank法检验。结果全组患者中位OS时间为19.1个月(95%CI为8.1~30.1),1、2、3年OS率分别为63.2%、47.4%和31.6%。pre-PTMV、mid-PTMV、Post-PTMV、ΔPTMV和ΔPTMV2的阈值分别为80.68(cm^3)、58.75(cm^3)、53.90(cm^3)、-35.02%和-13.65%。但只有治疗后PTMV比治疗中PTMV缩小体积在13.65%者有较高的总生存率,而根据其余各项阈值进行分组的两组之间没有差异。结论对于行CRT的中晚期食道癌患者,治疗前、中和后PTMV的绝对值以及治疗后PTMV/治疗前PTMV的变化率与患者的预后无关,治疗后PTMV/治疗期间PTMV的变化率对判断食道癌的预后总生存期相关,这一指标可为食道癌的个体化治疗提供指导。     

核医学18F-FDG PET/CT报告书写规范

随着正电子发射计算机断层显像/计算机断层显像(positron emission tomography/computed tomography, PET/CT)临床应用的增加,氟-18标记氟代脱氧葡萄糖(flurodeoxyglucose,18F-FDG)PET/CT的诊断作用得到了临床的广泛认可.18F-FDG PE...     

PET在阿尔茨海默病中的应用和进展

阿尔茨海默病（AD）是老年痴呆的主要类型,约占痴呆病例的60%~80%。随着我国人口平均寿命的延长和老年人口数量的增加,AD的发病率不断提高,给社会及家庭带来巨大的经济负担,引起了国内外学者的高度重视。PET是一种先进的临床影像检查技术,在AD的诊断和研究中具有更高的灵敏度和准确率。笔者就近年来PET在AD中的应用和进展进行综述。     

MRI和PET显像在阿尔茨海默病早期诊断中的应用

阿尔茨海默病（AD）是一种最常见的进行性神经退行性疾病,严重威胁患者的生命和健康,早期诊断和干预可以减缓甚至逆转该疾病的病情进展。目前,MRI和PET显像已被应用于AD的诊断,其在AD的早期诊断方面均有独特的优势。笔者重点介绍了结构性MRI、功能性MRI和PET显像在AD早期诊断中的应用。     

PET/CT和MRI在多发性骨髓瘤中的应用与进展

多发性骨髓瘤（MM）是一种恶性B细胞肿瘤,其主要累及骨髓,部分也可出现髓外浸润。影像学检查是全面评估MM不可或缺的手段,X射线与CT对病灶的检出率低、定量能力差。PET/CT与MRI对MM的评估具有较大的价值,特别是18F-FDG及其他新型分子探针,全身扩散加权成像、动态增强MRI及水脂分离等MRI新技术。笔者就PET/CT及MRI在MM中的应用与进展进行综述。     

阿尔茨海默病PET正电子药物应用与研究进展

阿尔茨海默病（AD）严重危害人们的身心健康。伴随PET分子成像的发展,出现了一系列针对AD的正电子药物,其中匹兹堡化合物B（PIB）及其衍生物类PET正电子药物研究最为成熟,部分已获准应用于临床,在AD诊断与治疗方面显示出重要价值。随着人们对AD发生机制研究的不断深入,近年又相继出现了包括蛋白类、受体类以及肽类在内的更多种类AD相关PET正电子药物。该文就此类正电子药物的应用与研究进展做一综述。     

放射性核素标记的胆碱在PET/CT肿瘤显像中的应用

18F-FDG PET/CT可明显提高恶性肿瘤诊断的准确性,指导恶性肿瘤的分期与再分期,对患者治疗方案的选择产生了重要影响。其在全身许多肿瘤中的应用价值已获得认可,但还存在一些不足。随着正电子标记药物的不断研发,放射性核素标记的胆碱逐渐应用于临床。胆碱是细胞膜的重要组成成分,恶性肿瘤的胆碱代谢增高。近年来的研究表明,胆碱PET/CT在胶质瘤、头颈部肿瘤、肺癌、肝细胞肝癌、前列腺癌、膀胱肿瘤等的诊断、分期及复发检测等方面具有很好的应用价值,特别是对颅内病变的观察、高分化肝细胞肝癌的诊断、生物靶区勾画、复发病灶的定位等,在一定程度上弥补了18F-FDG PET/CT的不足。笔者回顾了放射性核素标记的胆碱（11C-胆碱和18F-胆碱）在肿瘤显像中的应用。     

脑血管重度狭窄患者脑代谢与脑血流损害特点初步研究

目的：探讨脑血管重度狭窄或闭塞患者脑葡萄糖代谢与脑血流灌注的受损特点。方法采用18F-FDG和13N-Ammonia PET联合脑显像,对33例缺血性脑血管病（ICVD）患者进行检查,获得同期脑葡萄糖代谢和脑血流灌注影像。经半定量分析,得到脑代谢减低率、脑血流减低率和脑代谢/脑血流比值。结果①共发现病灶121个,18F-FDG显像阳性率为91．7%,13N-Ammonia显像阳性率为78．5%。②ICVD病灶呈多灶性和不对称性分布。③根据两种影像的匹配性,将病灶分为两大类（5种类型）：匹配型（I型）病灶66个,占54．5%;不匹配型（II型-V型）病灶55个,占45．5%。④以脑代谢/脑血流比值为指标,匹配型病灶的比值为1．10±0．13;不匹配型病灶比值增高组的95%CI为1．28-1．56,比值减低组的95%CI为0．95-1．08。将脑代谢/脑血流比值1．1-1．3作为区分匹配型与不匹配型的标准。⑤以脑代谢减低率和脑血流减低率为指标,将66个匹配型病灶分为轻度、中度、重度受损3组,各组之间的脑代谢、脑血流减低率差异均有统计学意义（χ2=56．854和56．800,P均＜0．01）。其中,轻度受损病灶27个,占40．9%;中度受损病灶15个病灶,占22．7%;重度受损病灶24个,占36．4%。⑥4例单侧脑内病变者可见交叉性小脑失联络。结论脑血管重度狭窄患者脑代谢与脑血流的匹配关系明显受损,但其中存在着不同程度的脑代谢与脑血流损害;脑代谢-脑血流联合PET显像在脑血管重度狭窄患者脑损伤程度的评估中具有重要意义和应用价值。     

Effectiveness of treatment with donepezil hydrochloride and changes in regional cerebral blood flow in patients with Alzheimer's disease

OBJECTIVE: The objective of this study was to elucidate the relationship between the effects of donepezil hydrochloride (donepezil) and cerebral blood flow, and to evaluate the usefulness of cerebral blood flow imaging in assessing and predicting treatment effectiveness. METHODS: The subjects were 29 outpatients (12 men and 17 women; age 50-82 years; mean age 69.2 years), who had received a diagnosis of Alzheimer's disease (AD). Efficacy was evaluated before donepezil administration; after 1 month, 3 months, and 6 months of drug administration; and at 1 year after completion of administration using the Japanese version of the Alzheimer's disease assessment scale-cognitive subscale (ADAS-cog), as a measure of cognitive function. The ADAS-cog has been frequently used to evaluate cognitive function in AD patients. Patients whose ADAS-cog scores improved by 3 or more points during the observation period were classified as responders, and those with no improvement were classified as nonresponders. (123)I-IMP was used for single photon emission computed tomography cerebral blood flow scintigraphy. RESULTS: On the basis of ADAS-cog score improvement, 22 of the 29 patients were responders (7 men and 15 women; age 50-82 years; mean age 69.0 years) and seven were nonresponders (5 men and 2 women; age 61-80 years; mean age 70.0 years). The results indicate that a difference in cerebral blood flow responsiveness after 1 month of treatment distinguishes responders from nonresponders. After 1 month, blood flow was significantly decreased in all regions of nonresponders, whereas significant increases in blood flow were seen in the anterior frontal lobe and parietal lobe of responders. At that time point, blood flow in the basal ganglion differed significantly between the two groups, indicating that this difference in responsiveness after 1 month of treatment may distinguish responders from nonresponders. CONCLUSIONS: In cognitive function testing, the group that exhibited a complete response showed improvement primarily in parameters reflecting frontal lobe function. Complete responders also showed significantly greater blood flow increases in the basal ganglion and thalamus early during the treatment period. This indicates that the drug responsiveness of the basal ganglion and thalamus affects frontal lobe function and distinguishes complete responders from patients who do not exhibit such a response.     

Assessment of cerebral perfusion with single-photon emission tomography in normal subjects and in patients with Alzheimer's disease: effects of region of interest selection

The shape, size and location of regions of interest (ROls) show considerable variability between single-photon emission tomography (SPET) studies in aging and Alzheimer's disease, but the possible influence on study results remains unknown. We compared three different ROIs in a SPET study with 60 controls and in 48 patients with probable Alzheimer's disease diagnosed according to the NINCDS-ADRDA criteria. Regional cerebral blood flow (rCBF) was assessed with SPET using technetium-99m d,l-hexamethylpropylene amine oxime (^99mTc-HMPAO), normalized to the mean activity in a cerebellar reference slice. The three different ROIs were: a multi-slice and a single-slice ROI with reference to the normal brain anatomy (using an anatomical atlas), and a rectangular (2×4 pixels) ROI in the frontal, temporal, temporoparietal and occipital cortices. No differences were observed for the means of rCBF values between the single-slice and multi-slice ROI's with reference to the normal anatomy, but some variability was present for individual comparisons. In contrast, significantly higher mean rCBF values were obtained with the single-slice rectangular ROls in all four regions for both patients and controls and considerable variability was shown for individual subjects. After analysis with multivariate logistic regression and receiver operator characteristic curves, the ability of SPET to discriminate between controls and Alzheimer patients was similar in the three methods for mild and moderate Alzheimer patients (Global Deterioration Scale = GDS of 3 and 4). However, with increasing dementia severity (GDS>4) the rectangular ROIs showed lower ability to discriminate between groups compared to the singleslice and multi-slice anatomically defined ROIs. This study suggests that results of rCBF assessment with SPET using ^99mTc-HMPAO in patients with severe Alzheimer's disease are influenced by the shape and size of the ROI.     

不同组织学类型肺癌患者大脑静息葡萄糖代谢改变研究

目的 探讨不同组织学类型肺癌患者大脑静息葡萄糖代谢改变特点.方法 回顾性分析100例未经治疗的原发性肺癌患者全身18F-FDG PET/CT检查资料.肺癌组织学类型均经穿刺或手术病理明确,根据不同组织学类型将患者分为腺癌（42例）、鳞癌（37例）、小细胞肺癌（21例）3组.将50名健康体检者作为对照,采用统计参数地形图分析软件分析每组患者PET脑代谢显像资料,采用两样本t检验比较3组患者脑代谢改变的差异.结果 3组患者脑PET显像均表现为区域性大脑静息葡萄糖代谢降低,主要分布在左侧额叶上中回及双侧颞叶上、中、下回,小细胞肺癌组还可见右侧顶下小叶及海马区受累.小细胞肺癌组低代谢脑区面积（体素数3848）大于腺癌组（体素数1436）（t=14.33,P＜0.05）和鳞癌组（体素数1397）（t=10.07,P＜0.05）,腺癌组与鳞癌组之间差异无统计学意义（t=0.764,P＞0.05）.结论 肺癌患者大脑静息葡萄糖代谢改变与其组织学类型有一定相关性.脑代谢降低区多涉及精神情感功能区,PET脑显像有望为肺癌患者出现的精神情感障碍症状提供客观的分子影像学依据和可能的评价指标.     

Artificial neural networks that use single-photon emission tomography to identify patients with probable Alzheimer's disease

Single-photon emission tomographic (SPET) images using technetium-99m labelled hexamethylpropylene amine oxime were obtained from 97 patients diagnosed as having Alzheimer's disease, as well as from a comparison group of 64 normal subjects. Multiple linear regression was used to predict subject type (Alzheimer's vs comparison) using scintillation counts from 14 different brain regions as predictors. These results were disappointing: the regression equation accounted for only 33.5% of the variance between subjects. However, the same data were also used to train parallel distributed processing (PDP) networks of different sizes to classify subjects. In general, the PDP networks accounted for substantially more (up to 95%) of the variance in the data, and in many instances were able to distinguish perfectly between the two subjects. These results suggest two conclusions. First, SPET images do provide sufficient information to distinguish patients with Alzheimer's disease from a normal comparison group. Second, to access this diagnostic information, it appears that one must take advantage of the ability of PDP networks to detect higher-order nonlinear relationships among the predictor variables.     

Regional cerebral glucose consumption measured by positron emission tomography in patients with Wilson's disease

Using positron emission tomography (PET), the regional cerebral metabolic rate of glucose consumption (rCMRGlc) was measured in 14 patients with Wilson's disease (WD) and 23 normal subjects. In WD patients, cerebellar, striatal and — to a lesser extent — cortical and thalamic rCMRGIc were significantly decreased compared with controls. Striatal rCMRGIc was significantly reduced in those 4 patients who had recently started decoppering therapy as compared with striatal rCMRGlc measured in those 10 patients with longer duration of medication. Caudate rCMRGlc correlated significantly with various signs of extrapyramidal dysfunction. Cerebellar, thalamic and cortical rCMRGlc correlated significantly with the severity of pyramidal signs. These data indicate that the PET measurement of rCMRGIc may be a useful tool to evaluate cerebral involvement in WD and to monitor the response to treatment. Offprint requests to: T. Kuwert     

The diagnostic value of PET/CT in recurrence and distant metastasis in breast cancer patients and impact on disease free survival

Aim of work

To detect the diagnostic value of PET/CT in breast cancer patients. We compared the performance of PET/CT with that of conventional imaging in detection of recurrence and distant metastasis and evaluated the impact PET/CT results have on disease free survival.

Materials and methods

We retrospectively studied 50 patients with breast cancer with clinical suspicion of recurrent or metastatic lesion and who underwent PET/CT and conventional imaging procedures. The imaging results were retrospectively compared with histopathology and clinical follow-up as a reference standard.

Results

PET/CT detected distant metastases with a sensitivity of 97% and a specificity of 93%. In contrast, the sensitivity and specificity of combined conventional imaging procedures were 75% and 73%, respectively, disease-free survival was significantly shorter in the 34 M1-PET/CT patients than in the 14 M0-PET/CT patients (log-rank P = 0.002) also PET/CT detected recurrence in 1 patient with equivocal mammographic findings.

Conclusion

In breast cancer, PET/CT is superior to conventional imaging procedures for detection of recurrence, distant metastases and PET/CT can be used to improve prediction of the clinical outcome of breast cancer patients.     

18F-FDG图像糖代谢定量分析中的输入函数及集总常数

LC(集总常数)是FDG(氟代脱氧葡萄糖)与葡萄糖的代谢率之比.不仅在不同的组织中LC有不同的值,而且在同一组织中,生理状态的变化也会引起LC变化.重点介绍了几种组织中的LC值以及LC的计算方法.另外,还介绍了几种获取输入函数的简化方法.     

HMPAO SPET and FDG PET in Alzheimer's disease and vascular dementia: comparison of perfusion and metabolic pattern

Positron emission tomography (PET) of ¹⁸F-2-fluoro-2-shirlyD-glucose (FDG) and single-photon emission tomography (SPET) of ^99mTc-hexamethyl-propylene amine oxime (HMPAO) were performed under identical resting conditions within 3 h in 20 patients with probable Alzheimer's disease (AD), 12 patients with vascular dementia (VD) and 13 normal persons. In the temporoparietal association cortex similar impairment of relative regional cerebral glucose metabolism (rCMRGI) and relative HMPAO uptake (rCBF) was found. In addition PET showed hypometabolism in the occipital association cortex. The functional pattern was condensed to a ratio of regional values of association areas divided by regional values of structures that are typically less affected by AD. In normals this ratio was significantly related to age for PET metabolic data (r = –0.66, P = 0.01). The ratio was significantly lower in AD than in VD and controls for both rCMRGI and rCBF. In AD only, the metabolic ratio was related to severity of dementia (r = 0.54, P = 0.003) and age (r = 0.64, P = 0.003). Metabolic differences between normals and AD patients were less obvious in old age. In contrast, there were no significant correlations between the perfusion ratio and severity of dementia or age. Comparing the metabolic and perfusion ratio by receiver operating characteristic curves, PET differentiated AD from normals only marginally better than SPET. Differentiation between AD and VD was much better achieved by PET. Our results suggest that both PET and SPET can distinguish AD patients from controls, whereas for differentiation between AD and VD SPET is of little value.     

Dipyridamole-induced increased glucose uptake in patients with single-vessel coronary artery disease assessed with PET

BACKGROUND: The aim of this study was to determine the relationship between vasodilatation-induced ischemia and poststress glucose uptake. Coronary vasodilators may induce myocardial ischemia due to coronary steal through collateral circulation or transmural blood flow redistribution with diminished subendocardial perfusion. Myocardial ischemia can be demonstrated by increased glucose uptake as previously shown in patients with exercise-induced ischemia. METHODS AND RESULTS: We studied 11 patients with single-vessel disease and no history of myocardial infarction. Five patients had no collateral circulation, and 6 had angiographic evidence of collateral vessels. We measured myocardial blood flow (MBF) and glucose uptake at baseline and after the administration of dipyridamole (0.56 mg/kg) with positron emission tomography, using O-15 water and fluorine 18 deoxyglucose (FDG) as perfusion and glucose tracers. MBF at baseline was 0.82 +/- 0.13 mL/g/min in normal areas and 0.80 +/- 0.15 mL/g/min in areas supplied by stenotic arteries. MBF during dipyridamole was 2.05 +/- 0.66 and 1.19 +/- 0.66 mL/g/min in normal areas and areas with stenotic arteries, respectively (P < or = .001). FDG uptake at baseline was 1.36 +/- 0.55 in normal areas and 1.57 +/- 0.62 in areas supplied by stenotic arteries. FDG uptake after dipyridamole infusion was 1.79 +/- 1.1 and 4.04 +/- 0.84 in normal areas and areas with stenotic arteries, respectively (P < or =.001). MBF and FDG uptake were not different between patients with collateral circulation and those without collateral circulation. CONCLUSIONS: Increased myocardial glucose uptake was consistently observed after dipyridamole administration in those areas with diminished coronary vasodilatory capacity. The similar MBF and FDG findings in patients with and without collateral circulation may indicate that transmural blood flow redistribution appears to be a possible mechanism of dipyridamole-induced myocardial ischemia.