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1.
PURPOSE: When the cerebral metabolic rate of glucose (CMRglc) is to be measured, arterial blood sampling is usually required for fluorine-18 fluorodeoxyglucose (FDG) and positron emission tomography (PET) studies. However, blood sampling is inconvenient because it requires several staff members and is invasive for patients. METHODS: To assess cerebral glucose metabolism by a noninvasive and simplified method, the authors used the standardized uptake value (SUV), which requires no input function or blood sampling. The study participants included 18 healthy volunteers (4 men and 14 women; mean +/- SD age, 68.2+/-6.3 years), 18 patients with mild Alzheimer's disease (AD) (4 men and 14 women; mean +/- SD age, 68.8+/-7.3 years), and 18 patients with moderate AD (5 men and 13 women, mean +/- SD age, 69.5+/-8.5 years). Regional CMRglc and regional cerebral SUV were measured in the three groups using FDG PET, and the correlation between global CMRglc and global SUV was estimated. RESULTS: The correlation coefficients of global CMRglc and global SUV in the healthy volunteers, mild AD patients, and moderate AD patients were 0.82, 0.67, and 0.62, respectively. Compared with the healthy persons, the patients with mild AD showed significantly decreased CMRglc in the temporal, frontal, and parietal cortices, but they did not show significantly decreased SUV in any region. Patients with moderate AD had significantly decreased CMRglc in the temporal, frontal, occipital, parietal, and sensorimotor cortices and significantly decreased SUV in the temporal, frontal, occipital, and parietal cortices. CONCLUSION: The SUV would be useful as a semiquantitative index of cerebral glucose metabolism only in healthy persons or those with mild AD.  相似文献   

2.
Benign and malignant pulmonary lesions usually are differentiated by 18F-FDG PET with a semiquantitative 18F-FDG standardized uptake value (SUV) of 2.5. However, the frequency of malignancies with an SUV of <2.5 is significant, and pulmonary nodules with low 18F-FDG uptake often present diagnostic challenges. METHODS: Among 360 consecutive patients who underwent 18F-FDG PET to evaluate pulmonary nodules found on CT, we retrospectively analyzed 43 who had solid pulmonary lesions (excluding lesions with ground-glass opacity, infiltration, or benign calcification) with an SUV of <2.5. The uptake of 18F-FDG was graded by a visual method (absent, faint, moderate, or intense) and 2 semiquantitative methods (SUV and contrast ratio [CR]). Final classification was based on histopathologic findings or at least 6 mo of clinical follow-up. RESULTS: We found 16 malignant (diameter, 8-32 mm) and 27 benign (7-36 mm) lesions. When faint visual uptake was the cutoff for positive 18F-FDG PET results, the receiver-operating-characteristic (ROC) analysis correctly identified all 16 malignancies and yielded false-positive results for 10 of 27 benign lesions. Sensitivity was 100%, specificity was 63%, and the positive and negative predictive values were 62% and 100%, respectively. When an SUV of 1.59 was the cutoff for positive 18F-FDG PET results, the ROC analysis revealed 81% sensitivity, 85% specificity, and positive and negative predictive values of 77% and 89%, respectively. At a cutoff for positive 18F-FDG PET results of a CR of 0.29, the ROC analysis revealed 75% sensitivity, 82% specificity, and positive and negative predictive values of 71% and 85%, respectively. The areas under the curve in ROC analyses did not differ significantly among the 3 analyses (visual, 0.84; SUV, 0.81; and CR, 0.82). Analyses of intra- and interobserver variabilities indicated that visual and SUV analyses were quite reproducible, whereas CR analysis was poorly reproducible. CONCLUSION: These results suggested that for solid pulmonary lesions with low 18F-FDG uptake, semiquantitative approaches do not improve the accuracy of 18F-FDG PET over that obtained with visual analysis. Pulmonary lesions with visually absent uptake indicate that the probability of malignancies is very low. In contrast, the probability of malignancy in any visually evident lesion is about 60%.  相似文献   

3.
Prognostic value of the standardized uptake value in esophageal cancer   总被引:1,自引:0,他引:1  
OBJECTIVE: On PET, the level of tissue glycolysis can be quantified by the accumulation of fluorine-18-fluorodeoxyglucose expressed as the standardized uptake value (SUV). The aims of this study were to investigate the relation between SUV and the stage of disease and whether SUV can be used to predict resectability and survival in patients with esophageal cancer. CONCLUSION: SUV can be used to predict resectability; however, SUV is not an independent factor that can be used to assess survival in patients with esophageal cancer.  相似文献   

4.
A threshold method to improve standardized uptake value reproducibility   总被引:5,自引:0,他引:5  
Although standardized uptake values (SUV) are widely used to quantify the uptake of 18F-fluorodeoxyglucose (18F-FDG) in tumours, there are systematic differences in the way this index is applied by different investigators. The aims of this study were to compare the effects of using maximum or mean region counts in the calculation of SUV and to investigate an alternative technique based on a fixed fraction of the maximum counts. Simulated PET projections of the thorax were generated together with spherical lesions that varied in diameter from 1.6 to 4.8 cm with uptake values of 2, 4 and 8. The lesion SUVs were determined using either the maximum (SUVmax) or mean count (SUVmean) values found in regions circumscribing the lesion. In addition, average values were calculated that only included region pixels that exceeded a selected fraction of maximum value (SUV0.6max or SUV0.75max). These methods were also applied to six clinical 18F-FDG PET studies with a total of 12 lesions. The SUVs for these lesions were determined independently by four observers. Decreases with respect to SUVmax of 57%, 23% and 14% were found for SUVmean, SUV0.6max and SUV0.75max approaches respectively in the simulation study. The variation in SUVmean with region size was 35%, while the SUV0.6max and SUV0.75max was less than 3%. Similar results were obtained for the clinical data. We conclude that the proposed technique produces SUVs that are essentially independent of lesion region size and shape. It is expected that this will provide a more stable and reliable result than current approaches.  相似文献   

5.
标准摄取值对肺良恶性病变的诊断价值   总被引:3,自引:0,他引:3  
目的:探讨肺18F-脱氧葡萄糖(FDG)PET显像标准摄取值(SUV)对肺良恶性病变的诊断价值。方法:18F-FDG PET显像肺内占位性病灶患者,用感兴趣区法计算病灶SUV,随访其手术病理检查,穿刺检查以及治疗转归等结果,比较综合临床诊断,不同SUV阈值对肺占位性病灶的诊断效果。结果:综合诊断66个肺部占位性病变的总灵敏度为94.5%,特异性为81.8%,不同SUV阈值的诊断效能均低地此水平,结论:18F-FDG PET对肺占位性病灶具有较高的诊断价值,综合诊断较单一SUV诊断具有更好效果。  相似文献   

6.
目的 分析嗜铬细胞瘤18 F-FDG PET/CT显像SUVmax与血浆游离甲氧基肾上腺素(MN)、甲氧基去甲肾上腺素(NMN)及131I-间位碘代苄胍(MIBG) SPECT显像间的关系,探讨18F-FDG PET/CT在诊断嗜铬细胞瘤和预测嗜铬细胞瘤恶性程度中的价值.方法 采用回顾性研究方法,收集经18F-FDG PET/CT检查且手术病理证实为嗜铬细胞瘤的患者19例,按其生物学行为分为良性组(n=11)与恶性组(n=8),查询PET/CT检查前后血MN、NMN及131 I-MIBG SPECT的检查结果,利用SPSS 17.0软件行两独立样本t检验,并绘制ROC曲线,探讨嗜铬细胞瘤SUVmax的特点,比较分析各检查之间的关系.结果 (1)11例良性嗜铬细胞瘤(BPCC)与8例恶性嗜铬细胞瘤(MPCC)PET/CT显像均为阳性;MPCC的SUVmax(19.40±7.39)明显大于BPCC的SUVmax (7.44±4.47),t=-4.40,P<0.01;用约登指数法,确定SUVmax=8.85为判断嗜铬细胞瘤良恶性的分界值,其灵敏度、特异性和准确性分别为8/8、81.8%(9/11)、89.5% (17/19);异位嗜铬细胞瘤SUVmax为19.75±8.64,明显高于肾上腺嗜铬细胞瘤SUVmax (9.12±5.83),t=-3.18,P<0.05;初发与复发的嗜铬细胞瘤SUVmax间差异无统计学意义(t=-1.68,P>0.05).(2)MN阴性病例SUVmax( 13.57±8.61)明显高于MN阳性病例SUVmax (6.63±2.42),t =2.70,P<0.05;NMN阴性与阳性的病例SUVmax间差异无统计学意义(t=-0.93,P>0.05).(3)7例同期行18F-FDG PET/CT与131I-MIBG SPECT患者中,3例BPCC,其中2例MIBG显像阳性,4例MPCC MIBG显像均为阴性;7例PET/CT显像均为阳性.结论 对于血MN与MIBG检查为阴性、但临床疑为嗜铬细胞瘤患者,FDG PET/CT可作为辅助诊断手段,减少漏诊率.  相似文献   

7.

Purpose

FDG PET/CT is an excellent tool to detect melanoma metastases and also allows quantification of FDG uptake using standardized uptake value (SUV). The aim of this study was to prospectively investigate the potential prognostic value of SUV for disease-free survival (DFS) and disease-specific survival (DSS) for patients with stage IIIB melanoma.

Methods

From November 2003 to March 2008, all consecutive patients were included in the present study. Inclusion criteria were: palpable, histology- or cytology-proven lymph node metastases of melanoma, and referred to the University Medical Centre Groningen for FDG PET and CT examination. Patients without distant metastases were evaluated. Multivariable survival analysis was performed to determine whether SUV was associated with DFS and DSS (Cox proportional hazard analysis).

Results

In 80 patients (without distant metastases, 65?%) SUV could be measured. Overall 5-year DFS was 41?% (95% CI 26–56?%) and 24?% (95% CI 12–38?%) in patients with a low and high SUVmean (p?=?0.02), respectively. Overall 5-year DSS was 48?% (95% CI 31–62?%) and 30?% (95% CI 17–45?%) in patients with a low and high SUVmean (p?=?0.04), respectively. In the multivariable analysis, SUVmean was associated with DFS (hazard ratio 1.7; p?=?0.048), but was not associated with DSS (hazard ratio 1.6; p?=?0.1). The number of positive nodes, extranodal growth and gender were also associated with survival.

Conclusion

FDG uptake in clinically overt nodal melanoma metastases is inversely associated with DFS. Univariate analysis showed an association with DSS. However, after adjustment for potential confounders this association was no longer significant. If these findings are confirmed in larger studies, SUVmean could potentially be used (in addition to the number of positive nodes, tumour size and extranodal growth) as a factor in deciding on adjuvant systemic treatment.  相似文献   

8.
To reduce the variability of the standardized uptake value (SUV) which is widely used to evaluate 2-[18F]fluoro-2-deoxy-d-glucose (FDG) uptake by neoplasms, net influx constant (Ki) was derived from SUV. The relationship Ki=SUV·kp·V 0, where k p is the plasma clearance rate and V 0 is the initial distribution volume of FDG, was utilized. A total of 71 plasma input functions were measured up to 60 min after intravenous injection of FDG in 55 patients and were analysed to obtain k p and V 0. SUV and V 0 were calculated based on either body weight or body surface area. To validate the Ki estimation, another group of eight patients with squamous cell carcinoma of the head and neck was included. Parametric images of the net influx constant were obtained by Patlak graphical analysis of dynamic positron emission tomography (PET) data and measured plasma input function. V 0 based on body weight was 0.1627±0.0329 (ml/g) and showed a weak negative correlation with body weight (y=0.23356–0.00138x, r=0.591). V 0 based on body surface area was 5540±871 (ml/m2) and had no significant correlation with body weight. k p at 50 min post injection was 0.03272±0.00243 (1/min), and had no correlation with the plasma glucose concentration. A highly significant positive correlation was noted between true Ki and estimated Ki based on both body weight (y=0.0033+1.0371x, r 2=0.897), and body surface area (y=0.0033+1.0351x, r 2=0.926). Ki, a better indicator of FDG uptake by tumour than SUV, is derivable non-invasively. Quantification of FDG uptake by Ki will aid standardization of diagnostic criteria of FDG PET oncology. Received 1 December 1997 and in revised form 9 February 1998  相似文献   

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11.
目的 探讨三维平均CT值和PET/CT最大标准化摄取值(SUVmax)对磨玻璃密度结节(GGN)型肺腺癌侵袭性的预测价值.方法 回顾性分析经手术病理证实的81例表现为GGN的肺腺癌,均行PET/CT和HRCT检查.在病变最大直径的CT横断面上测量其平均直径(最大径和垂直径的均值);逐层手动描绘出GGN的轮廓,计算GGN的三维平均CT值;记录18 F-脱氧葡萄糖(18F-FDG) PET/CT的SUVmax.按照病理类型分为浸润前病变、微浸润腺癌、浸润性腺癌3组,并统计3组间肿瘤大小、三维平均CT值及SUVmax之间是否有统计学差异.结果 浸润前病变、微浸润腺癌和浸润性腺癌的肿瘤大小分别为(10.53士4.3)mm、(11.6±6.07)mm、(20.3士9.0)mm;三维平均CT值分别为(-568.59士128.7) HU、(-522士100.51)HU、(-321.9±165.2)HU;SUVmax分别为0.15±0.43、0.00±0.00、2.51±2.61,3组间差异有明显统计学意义(F值分别为11.06、18.624、9.06,P<0.001).受试者工作特征曲线(ROC)显示,肿瘤大小、三维平均CT值、SUVmax的诊断价值中等,曲线下面积(AUC)分别为0.855、0.867、0.895.三者分别取最佳临界值11.5 mm、-486 HU、0.95,其相对应的诊断浸润性病变的敏感度分别为91.5%、83.1%、79.7%;特异度分别为68.2%、77.3%、95.5%.结论 肿瘤大小、三维平均CT值、SUVmax是判断GGN型腺癌侵袭性的重要预测因子.  相似文献   

12.
目的 分析良恶性腹腔积液患者18 F-FDG PET/CT显像特点,探讨腹腔积液SUV对不明原因腹腔积液的辅助诊断价值.方法 回顾性分析首次18 F-FDG PET/CT检查前病因不明、但随访诊断明确的腹腔积液患者55例,其中男24例,女31例,年龄23~82(平均54.8)岁;良性腹腔积液19例,恶性腹腔积液36例.测定良恶性腹腔积液的SUV,并计算其与正常肝脏SUV的比值(T/NT).比较PET/CT肿瘤定位诊断、腹腔积液代谢判定及细胞学检查三者的诊断效能.采用两样本t检验、x2检验或确切概率法分析数据.结果 恶性腹腔积液患者18F-FDG PET/CT显像示腹腔积液代谢升高,MIP图像呈肝脾“淹没征”.恶性腹腔积液的SUVmax及SUVmax.分别为1.78±0.65和1.37±0.38,良性腹腔积液的相应值分别为1.11 ±0.36和0.72±0.22,前者明显高于后者(t=4.13、6.82,均P<0.05).恶性腹腔积液的T/NT值明显高于良性腹腔积液(基于SUVmax的T/NT值:0.64±0.20与0.48±0.12,t=3.27;基于SUVmean.的T/NT值:0.68±0.17与0.38±0.10,t=7.21,均P<0.05).根据腹腔积液代谢诊断恶性腹腔积液的灵敏度、特异性及准确性分别为75.0%(27/36)、94.7%(18/19)和81.8%(45/55),其灵敏度及准确性明显高于腹腔积液细胞学检查[44.4%(16/36)与63.6%(35/55);X2=6.98和4.58,均P<0.05],其特异性明显高于PET/CT肿瘤定位诊断[63.2% (12/19)X2=5.70,P<0.05].结论 腹腔积液代谢升高对恶性腹腔积液的辅助诊断具有重要价值,18 F-FDG PET/CT阅片分析应密切结合腹腔积液SUV及与肝脏的T/NT值,以进一步提高对不明原因腹腔积液的良恶性鉴别诊断效率.  相似文献   

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The aim this study was to evaluate potential additional information of pulmonary angiography in patients with suspected pulmonary embolism and non-diagnostic lung scan findings. In a series of 150 patients who underwent pulmonary angiography for suspected venous thromboembolism, the images for potential alternative diagnoses other than pulmonary embolism were evaluated. All patients had non-diagnostic lung scan findings. Angiography was performed both by conventional and by digital subtraction angiography techniques. Images were evaluated by at least two experienced readers. Angiograms were scored for both presence or absence of pulmonary embolism, as well as other diagnoses. Pulmonary embolism was proven in 40 patients (27 %) and excluded in 105 patients (70 %), whereas non-interpretable images were obtained in 5 patients (3 %). A range of alternative diagnoses were detected by angiography: atelectasis (n = 24), pleural effusion (n = 15), pneumonia (n = 11), emphysematous bullae (n = 8), neoplasm (n = 3), atrial septum defect (n = 2), chronic thromboembolism (n = 1), and other diagnoses (n = 3). Overall, only 54 patients (36 %) had completely normal angiograms. Although pulmonary angiography remains the reference method for the diagnosis of pulmonary embolism, one has to be aware of other, often unexpected, but equally important findings which could influence the management of the patient. This aspect of pulmonary angiography has been insufficiently emphasized in the literature. Received: 2 April 1998; Revision received: 22 July 1998; Accepted: 4 November 1998  相似文献   

15.
18F-FDG代谢显像标准摄取值的影响因素   总被引:1,自引:1,他引:0  
18F-FDG(18F-氟代脱氧葡萄糖)代谢显像在肿瘤、心肌存活及某些中枢神经系统疾病的研究、诊断中有着独特的临床应用价值,18F-FDG SUV(标准化摄取值)既能间接反映组织葡萄糖代谢率,又是一种简便快捷的临床常用影像半定量分析方法,但其影响因素众多,其中包括患者的身高、体重、血糖及胰岛素水平、显像时间以及感兴趣区的设置等,因此,临床应用过程中应注意对SUV测定的标准化.  相似文献   

16.

Purpose

To determine whether the relative metabolic activity of pelvic or para-aortic LN compared with that of primary tumor measured by preoperative [18F]FDG PET/CT scan has prognostic value in patients with endometrioid endometrial carcinoma.

Methods

We retrospectively reviewed patients with endometrioid endometrial carcinoma who underwent preoperative [18F]FDG PET/CT scans. Prognostic values of PET/CT-derived metabolic variables such as maximum standardized uptake value (SUV) of the primary endometrial carcinoma (SUVTumor) and LN (SUVLN), and the LN-to-endometrial carcinoma SUV ratio (SUVLN / SUVTumor) were assessed.

Results

Clinico-pathological data, imaging data, and treatment results were reviewed for 107 eligible patients. Median post-surgical follow-up was 23 months (range, 6–60), and 7 (6.5%) patients experienced recurrence. Regression analysis showed that SUVLN / SUVTumor (P < 0.001), SUVLN (P = 0.003), International Federation of Gynecology and Obstetrics (FIGO) stage (P = 0.006), and tumor grade (P = 0.011) were risk factors of recurrence. Multivariate regression analysis revealed that FIGO stage (P = 0.034) was the independent risk factor of recurrence. SUVLN / SUVTumor showed significant correlation with FIGO stage (P < 0.001), LN metastasis (P < 0.001), lymphovascular space invasion (P < 0.001), recurrence (P = 0.001), tumor grade (P < 0.001), and deep myometrial invasion of tumor (P = 0.022). Patient groups categorized by SUVLN / SUVTumor showed significant difference in progression-free survival (Log-rank test, P = 0.001).

Conclusions

Preoperative SUVLN / SUVTumor measured by [18F]FDG PET/CT was significantly associated with recurrence, and may become a novel prognostic factor in patients with endometrioid endometrial carcinoma.
  相似文献   

17.
The aim of this study was to evaluate the usefulness of measuring the standardized uptake value (SUV) in primary brain tumors on fluorine-18 fluorodeoxyglucose (FDG) positron emission tomography (PET) scans. Two groups of patients were studied. Whole-brain glucose cerebral metabolic rates (wCMRs) and SUVs were obtained in 20 normal subjects. Twenty-seven patients with histology-proven malignant primary CNS tumors (high-grade gliomas n=22, primitive neuroectodermal tumors n=3, ependymomas n=2) were also studied. The degree of FDG uptake was assessed by visual inspection and thereafter regions of interest were placed over the lesion, the contralateral cortex and white matter and the whole brain. Average (avg) and maximum (max) pixel values were determined in each site. Based on these measurements, SUV, tumor to cortex (T/C) and tumor to white matter (T/WM) activity ratios were calculated. There was no correlation between wCMRs (4.55±0.36 mg min–1 100 g–1) and wSUVs (5.41±0.43) in the normal subjects (r=0.18, P=0.45). In the second group,17 lesions were described as definitely and seven as probably malignant. However, SUVs in these tumors and in the contralateral cortex were not significantly different. Although the SUVs were generally higher in the tumor than in the contralateral white matter, there was a significant overlap between the values. The range of the SUVs was wide: 2.54–11.8 for the tumors, 2.98–9.96 for the cortex and 1.87–6.76 for the white matter. SUVs in the normal cortex were negatively correlated with blood glucose level at the time of the injection. SUVs in the whole brain and in the cortex were lower in patients previously treated by irradiation, even months after completion of the treatment. No correlation was detectable between any of the SUVs and the age of the patients, tumor type, time post injection, use of dexamethasone, patient weight, dose injected and visual score. With cutoff levels of 1.5 for T max/WM and 0.6 for T max/C, the sensitivity of the activity ratios was 74% and 96% respectively. In conclusion, SUVs do not correlate with CMRs across subjects and appear to be of limited value in characterizing brain tumors. Visual assessment and measurement of the activity ratios currently remain the most reliable methods of analysis.  相似文献   

18.
The aim of this study was to evaluate the usefulness of measuring the standardized uptake value (SUV) in primary brain tumors on fluorine-18 fluorodeoxyglucose (FDG) positron emission tomography (PET) scans. Two groups of patients were studied. Whole-brain glucose cerebral metabolic rates (wCMRs) and SUVs were obtained in 20 normal subjects. Twenty-seven patients with histology-proven malignant primary CNS tumors (high-grade gliomas n=22, primitive neuroectodermal tumors n=3, ependymomas n=2) were also studied. The degree of FDG uptake was assessed by visual inspection and thereafter regions of interest were placed over the lesion, the contralateral cortex and white matter and the whole brain. Average (avg) and maximum (max) pixel values were determined in each site. Based on these measurements, SUV, tumor to cortex (T/C) and tumor to white matter (T/WM) activity ratios were calculated. There was no correlation between wCMRs (4.55+/-0.36 mg min(-1) 100 g(-1)) and wSUVs (5.41+/-0.43) in the normal subjects (r=0.18, P=0.45). In the second group, 17 lesions were described as definitely and seven as probably malignant. However, SUVs in these tumors and in the contralateral cortex were not significantly different. Although the SUVs were generally higher in the tumor than in the contralateral white matter, there was a significant overlap between the values. The range of the SUVs was wide: 2.54-11.8 for the tumors, 2.98-9.96 for the cortex and 1.87-6.76 for the white matter. SUVs in the normal cortex were negatively correlated with blood glucose level at the time of the injection. SUVs in the whole brain and in the cortex were lower in patients previously treated by irradiation, even months after completion of the treatment. No correlation was detectable between any of the SUVs and the age of the patients, tumor type, time post injection, use of dexamethasone, patient weight, dose injected and visual score. With cutoff levels of 1.5 for T max/WM and 0.6 for T max/C, the sensitivity of the activity ratios was 74% and 96% respectively. In conclusion, SUVs do not correlate with CMRs across subjects and appear to be of limited value in characterizing brain tumors. Visual assessment and measurement of the activity ratios currently remain the most reliable methods of analysis.  相似文献   

19.
目的:探讨单纯标准摄取值(SUV)及综合判断在肺内占位病变诊断中的价值。方法:行PET检查并经病理检查证实的肺部占位病变患者共80例,对其PET显像结果进行分析。结果:单纯SUV诊断的准确性、灵敏度、特异性分别为72.5%,76.0%,65.0%;综合判断的准确性、灵敏度、特异性分别为88.8%,90.0%,84.6%。结论:依据SUV结合临床资料进行综合判断,可显著提高PET显像鉴别肺部良恶性病变的准确性。  相似文献   

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