18F-FDG PET-CT对裸鼠鼻咽癌移植瘤放疗疗效的早期评估及与Ki67表达的相关性研究

Objective To investigate the value of 18F-FDG PET-CT scans on early assessing the therapeutic effects on human nasopharyngeal carcinoma (NPC) xenograft in nude mice after radiotherapy,and preliminarily analyze the relation of 18F-FDG PET-CT scans and the positive expression rate of Ki67, and provide a basis for further clinical studies. Methods Fifteen xenograft nude mice of NPC were randomly divided into three groups (5 nude mice per group). Control group: all mice immediately executed after the 18F-FDG PET-CT scans and taken pathology; 6 Gy radiotherapy group: all mice took 18F-FDG PET-CT scans before and 1 d after receiving 6 Gy irradiation, and were killed immediately to take pathology; 12 Gy radiotherapy group: all mice received 12 Gy irradiation (6 Gy each time, totally 2 times). They took 18F-FDG PET-CT scans before radiotherapy, after receiving the first 6 Gy irradiation, 2 d and 6 d after receiving 12 Gy irradiation respectively ,and then were executed to take pathology after the last scan. The expression of Ki67 in xenografts of different groups was detected and the relation between their changes and T/NT were analyzed.Results ①For 12 Gy radiotherapy group, the average T/NT ratios of the NPC xenograft of pre-radiotherapy, after the first 6 Gy irradiation, 2 d and 6 d after 12 Gy radiotherapy were 2.17±0.31, 1.68±0.42, 1.41±0.40,and 0.70±0.12, respectively. The average T/NT ratios were not statistically difference before and after the first 6 Gy irradiation. The average T/NT ratio of 2 d after radiotherapy decreased significantly than pre-radiotherapy (t=2.80, P<0.05) and after the first 6 Gy irradiation (t=3.14, P<0.05); The average T/NT ratio of 6d after radiotherapy was decreased seriously than 2 d after radiotherapy(t=3.49, P<0.05, compared with preradiotherapy t=8.01, P<0.01). ② The positive expression rates of Ki67 of NPC xenograft markedly decreased after receiving irradiation. There were significant differences in the positive expressions of Ki67 between different group s(F=21.95, P<0.01).The positive expression of Ki67 in the 12 Gy radiotherapy group decreased significantly compared with the control group (t=7.145, P<0.01) and the 6 Gy radiotherapy group (t=2.384, P<0.05). The positive expression of Ki67 in the 6 Gy radiotherapy group was less than the control group, also have statistical significance(t=4.320, P<0.01).③There was no correlation between the T/NT ratio of NPC xenograft and the positive expression of Ki67. ④Positive correlation was found between the variance of T/NT ratio and the variance of the positive expression of Ki67 of NPC xenograft (r=0.532, P<0.05).Conclusions 18F-FDG PET-CT imaging has an important value on early assessing the therapeutic effects of NPC xenograft in nude mice after radiotherapy, and the 6th day after radiotherapy is an appropriate time point.18F-FDG PET-CT imaging can reflect the variance of the positive expression of Ki67 of NPC, and yet indirectly reflect the sensitivity of NPC to radiotheraphy.     

不同校正方法对SPECT/CT心肌灌注显像结果的影响

目的探讨不同校正方法对SPECT/CT心肌灌注显像图像质量及半定量结果的影响。资料与方法回顾性分析60例99Tcm-甲氧基异丁基异腈(99Tcm-MIBI)运动负荷及静息心肌灌注显像患者,均进行CT衰减校正(CTAC)和双能窗散射校正(SC)。分别重建CTAC、SC、CTAC+SC以及无衰减校正和散射校正(NOC)图像。利用靶心图获得不同校正状态左心室各壁段的放射性计数百分比,以及运动负荷和静息图像灌注缺损半定量评分,比较不同校正状态下缺血心肌图像质量和半定量结果的差异。结果运动负荷显像左心室心尖部、下后壁、间壁、侧壁放射性计数百分比在不同校正方法间差异有统计学意义(P均<0.05)。负荷总体灌注不足率、负荷灌注总评分、静息-负荷差异总评分在不同校正方法间差异有统计学意义(P均<0.05),其在SC图像中明显高于NOC图像(P均<0.05),在CTAC+SC图像中明显高于CTAC图像(P均<0.01)。目测比较SC图像缺血心肌的稀疏程度明显高于NOC图像,CTAC+SC图像明显高于CTAC图像,其中以CTAC+SC图像对缺血部位的显示最为清晰。比较不同校正状态缺血心肌放射性分布评分,缺血程度为3分的比例在SC图像中明显高于NOC图像(X^2=4.953,P=0.026),在CTAC+SC图像中明显高于CTAC图像(X^2=7.216,P=0.007)。结论不同校正状态下左心室缺血心肌图像质量及半定量结果出现明显差异,SC能显著改善缺血心肌的显示,尤其在CTAC图像中更为显著。     

心肌断层显像心肺摄取比值与核素心室造影左心功能的对比分析

【目的】探讨核素心肌断层显像时利用心肺摄取比值评价左心功能的价值。【方法】用99mTc甲氧基异丁基异腈( MIBI) 和99mTc红细胞(RBC) 对21 例健康对照者,42 例冠心病心功能正常者和43 例冠心病心功能受损者分别进行心肌断层显像和平衡法门控核素心室造影。从静息心肌断层显像的左前位像和平衡法门控核素心室造影。从静息心肌断层显像的左前位像(LAO12°) 中测出心肺计数比值(HIR) ,从门控核素心室造影中计算出左心室射血分数(LVER) 、左心室最大充盈率(LVPFR) 、左心室最大射血率(LVPER) 。【结果】健康对照组和冠心病心功能正常组的HLR 均高于冠心病心功能受损组( P < 0 .01) ;健康对照组和冠心病心功能正常组的HLR 差异无显著性( P > 0 .5) 。【结论】心肌断层显像时HLR 在反映冠心病患者心功能方面具有明确的实用价值。     

乳腺癌^18F-FDG PET／CT标准化摄取值与P53表达关系的研究

目的探讨^18F-脱氧葡萄糖（FDG）PET／CT的最大标准化摄取值（SUVmax）与乳腺癌P53表达之间的关系。方法回顾性分析PET／CT诊断的乳腺癌患者,且计算病灶最大SUV（SUVmax）;所有病例均手术后病理证实且进行免疫组化检查（P53检测）。结果118例乳腺癌患者中,P53阳性组占64．4％;P53阳性组与P53阴性组的年龄之间差别不具有统计学意义;P53阳性乳腺癌患者组平均SUVmax为5．06±1．47;而P53阴性乳腺癌患者组平均SUV—max为3．16±0．69,组间SUVmax比较差异具有统计学意义。本试验ROC曲线显示,SUVmax诊断P53表达正确率受试者工作特征（Receiver operating characteristic,ROC）曲线的曲线下面积达0．910±0．028,用SUVmax诊断P53表达具有统计学意义（P=0．000）;根据ROC曲线发现SUV分界值为3．785,其诊断敏感性为85．5％,特异性为81．0％。结论利用^18F-FDGPET／CT显像的SUVmax早期评价乳腺癌P53表达情况可作为一种新的评价方法,初步认为,将SUVmax〉3．785作为乳腺癌P53表达的一个分界值有一定的科学意义。     

心肌断层显像心肺摄取比值与核素心室造影左心功能的对比分析

目的：探讨核素心肌断层显像时利用心肺摄取比值评价左心功能的价值。方法：用＾９９ｍ＾Ｔｃ－甲氧基异丁基异腈（ＭＩＢＩ）和＾９９ｍＴｃ－红细胞（ＲＢＣ）对２１例健康对照者，４２例冠心病心功能正常者和４３例冠心病心功能受损者分别进行心肌断层显像和平衡法阂控核素心室造影。从请息心肌断层显像的左前位像和平衡法门控核素心室造影。从静息心肌断层显像的左前位像（ＬＡＯ１２°）中测出心肺计数比值（ＨＩＲ），从门控核     

201Tl定量门控心肌灌注体层显像与99mTc-红细胞门控心血池显像测定左心室射血分数的对比研究

目的 探讨201Tl定量门控心肌灌注体层显像与99mTc-红细胞门控心血池显像测量左心室射血分数(LVEF)的相关性.方法 72例受检者接受201Tl静息门控心肌灌注体层显像,用AUTOQUANT 4.21软件测量LVEF,并与24 h内的静息99mTc-红细胞平衡法门控心血池显像结果进行比较.结果 ①门控心肌灌注体层显像与门控心血池显像测量LVEF值的结果呈明显正相关(r=0.554,P=-0.000),两种方法无统计学差别(t=1.194,P＞0.05).②不同疾病组之间两种测量方法无统计学差异(P值均大于0.05).③门控心肌灌注体层显像及门控心血池显像测量的LVEF值分别为(64.68±10.77)%和(62.46±8.99)%,门控心肌灌注体层显像测量的LVEF值要比门控心血池显像高出3.55%.结论 201Tl门控心肌灌注体层显像与99mTc-红细胞门控心血池显像测量LVEF值的相关性好且结果准确,但门控心肌灌注体层显像的LVEF测量值要稍高于门控心血池显像.     

抗人肝癌188Re-免疫磁性纳米微粒的生物学分布和肿瘤细胞抑制实验

目的探讨抗人肝癌188Re-免疫(Hepama-1)磁性纳米微粒免疫学活性、体内生物学分布、肝靶向性及抑瘤作用。方法对比188ReO4-、188Re-Hepama-1、188Re-磁性纳米微粒,研究尾静脉注射188Re-免疫磁性纳米微粒后4h、24h在昆明小鼠体内的分布情况;在肝区外加磁场及无磁场状态下,研究新西兰大白兔体内的肝磁靶向性;采用溴化四甲基唑法,研究4种188Re标记物对肝癌细胞株SMMC-7721的抑制效果。结果188Re-免疫磁性纳米微粒在肝内摄取量最大;在磁区肝组织放射活性较非磁区肝组织明显增加,二者的放射活性比值为1.87;对肝癌细胞株SMMC-7721半数抑制放射性活度仅为188ReO4-的1/4左右。结论188Re-磁性纳米微粒具有良好的磁感应性能、免疫活性及明显的肝靶向性。     

18F-FDG PET/CT显像诊断甲状腺癌复发和转移的价值

^18F-脱氧葡萄糖（FDG）PET显像对诊断甲状腺癌术后甲状腺球蛋白（Tg）水平升高患者有较大价值.笔者对21例血清Tg水平升高而疑甲状腺癌复发患者行PET/CT显像,并与^131I全身显像比较,现将结果报道如下.     

PET性能测量——2001版NEMA标准

2001版“PET性能测量”的NEMA(美国电器制造商协会)标准是对1994年版本NEMA标准的修订，使之适合于各类PET(正电子发射体层显像)仪的质量保证和验收测量。内容主要包括以下几个部分：(1)定义、符号和参考出版物；(2)总论；(3)空间分辨率；(4)散射因子、计数丢失和随机符合测量；(5)灵敏度；(6)精确性：计数丢失和随机符合校正；(7)图像质量、衰减和散射校正精确性。