双时相18F-FDG PET/CT显像诊断不同类型肝外胆管癌

目的 探讨双时相¹⁸F-FDG PET/CT显像诊断不同类型肝外胆管癌（EHCC）的价值。方法 回顾性分析71例疑诊EHCC并接受双时相¹⁸F-FDG PET/CT显像患者，根据PET/CT显像及病理结果将其分为结节型EHCC组（n=20）、非结节型EHCC组（n=34）及良性病变组（n=17），计算双时相PET/CT显像的诊断效能；比较双时相PET/CT显像中3组阳性显像病灶最大标准摄取值（SUV_max）、肿瘤SUV_mean/肝脏SUV_max（T/L）及滞留指数（RI）的差异，以ROC曲线比较各参数AUC，并分析其临界值。结果 早期¹⁸F-FDG PET/CT显像及延迟显像对非结节型EHCC的诊断灵敏度分别为70.59%（24/34）和73.53%（25/34）。显像阳性患者中，结节型EHCC组SUV_max、T/L均明显高于良性病变组（P均<0.05）。非结节型EHCC组SUV_max、T/L与良性病变组差异均无统计学意义（P均>0.05），但SUV滞留指数（RI_SUV）差异存在统计学意义（Z=-2.638，P=0.007），RI_SUV最佳诊断临界值为6.0%。联合应用早期SUV_max>3.1和RI_SUV>6.0%可明显提高对非结节型EHCC的诊断灵敏度和准确率。结论 双时相¹⁸F-FDG PET/CT显像有助于提高对非结节型EHCC的诊断效能。     

68Ga-DOTA-TATE与18F-FDG PET/CT对比显像用于神经内分泌肿瘤

目的 观察⁶⁸Ga-1,4,7,10-四氮杂环十二烷-1,4,7,10-四乙酸-D-苯丙氨酸1-酪氨酸3-苏氨酸8-OC（DOTA-TATE）和¹⁸F-FDG PET/CT显像用于神经内分泌肿瘤（NET）的临床价值。方法 回顾性分析39例疑似NET并先后接受⁶⁸Ga-DOTA-TATE和¹⁸F-FDG PET/CT显像患者,以组织病理学诊断结果为金标准,分析2种显像对NET的诊断效能,比较不同病理分级NET病灶的⁶⁸Ga-DOTA-TATE和¹⁸F-FDG最大标准摄取值（SUV_max）。结果 ⁶⁸Ga-DOTA-TATE PET/CT显像诊断NET的敏感度、特异度、阳性预测值（PPV）、阴性预测值（NPV）及准确率分别为96.55%（28/29）、80.00%（8/10）、93.33%（28/30）、88.89%（8/9）及92.31%（36/39）,¹⁸F-FDG PET/CT显像分别为82.76%（24/29）、100%（10/10）、100%（24/24）、66.67%（10/15）及87.18%（34/39）。39例中,29例获得病理分级,包括5例G1级、16例G2级和8例G3级 NET;其中G1级、G2级及G3级NET在⁶⁸Ga-DOTA-TATE PET/CT中的SUV_max分别为28.80（15.20,44.80）、10.55（5.98,22.93）及4.70（3.90,7.50）,3个级别差异具有统计学意义（H=9.06,P=0.01）;其在¹⁸F-FDG PET/CT中的SUV_max依次为3.10（2.38,5.85）、3.10（1.82,5.18）、7.10（1.70,9.93）,3个级别差异无统计学意义（H=2.19,P=0.34）。结论 ⁶⁸Ga-DOTA-TATE PET/CT显像用于诊断NET及分期的价值高于¹⁸F-FDG PET/CT,且其SUV_max与病理分级相关。     

18F-AlF-NOTA-octreotide联合18F-FDG PET/CT显像用于神经内分泌瘤

目的 观察¹⁸F-AlF-NOTA-octreotide（¹⁸F-OCT）联合¹⁸F-FDG PET/CT显像用于神经内分泌瘤（NET）的临床价值。方法 回顾性分析21例同期接受¹⁸F-OCT和¹⁸F-FDG PET/CT显像并经病理学证实的NET患者,其中7例已接受原发瘤根治性切除术、2例原发灶不明;根据2010年WHO分级标准,将12例明确存在原发瘤者分为中/低级别组9例和高级别组3例,对比原发瘤及转移灶在2种显像中的阳性比例、摄取水平及治疗后影像学变化。结果 原发瘤大小与¹⁸F-FDG最大标准摄取值（SUV_max）显著相关（r=0.731,P<0.05）,但与¹⁸F-OCT无明显相关（r=0.311,P>0.05）。中/低级别组9例原发瘤中,8例¹⁸F-OCT显像阳性,SUV_max中位数为33.80（6.10,56.55）;7例¹⁸F-FDG显像阳性,SUV_max中位数3.80（1.40,8.80）（Z=-2.345,P<0.05）。高级别组3例原发瘤中,¹⁸F-FDG检出3例,¹⁸F-OCT 2例。¹⁸F-OCT联合¹⁸F-FDG PET/CT显像检测转移灶阳性比例高于单一。追踪观察1例胰腺NET术后肝脏多发转移患者,奥曲肽对其¹⁸F-OCT显像阳性病灶取得良好疗效。结论 ¹⁸F-OCT联合¹⁸F-FDG PET/CT显像可作为检测NET的辅助手段,并有望用于预估疗效。     

18F-FDG PET/CT诊断梗阻性黄疸的价值

目的 探讨¹⁸F-FDG PET/CT在梗阻性黄疸病因诊断中的价值。方法 28例梗阻性黄疸患者根据梗阻病因分为良性梗阻组（n=11）和恶性梗阻组（n=17）,对比分析两组患者¹⁸F-FDG PET/CT的显像特征、最大标准摄取值（SUV_max）水平;比较PET/CT、MRI诊断梗阻性黄疸的效能。结果 28例患者中,胆道无或轻度扩张15例（15/28,53.57%）,中-重度扩张13例（13/28,46.42%）。恶性梗阻组中,肝门胆管癌2例、胆总管癌5例、胰头癌6例、壶腹癌4例,其中14例¹⁸F-FDG PET/CT显像表现为梗阻部位近端高代谢结节。良性梗阻组中,胆道炎性狭窄7例,其中4例合并胆管结石,¹⁸F-FDG PET/CT显像6例表现为相应梗阻部位条片状或结节状轻度代谢增高;自身免疫性胰腺炎4例,¹⁸F-FDG PET/CT显像表现为胰腺多节段性多发条带状或结节状肿大,代谢普遍性增高。恶性梗阻组SUV_max（6.88±2.81）明显高于良性梗阻组SUV_max（4.20±1.70;t=3.143,P<0.05）。¹⁸F-FDG PET/CT、MRI诊断恶性梗阻性黄疸的敏感度为94.12%（16/17）和58.82%（10/17）,差异有统计学意义（χ²=4.086 5,P=0.043）,特异度为81.82%（9/11）和63.64%（7/11）,差异无统计学意义（χ²=0.229 2,P=0.632）,准确率为89.29%（25/28）和60.71%（17/28）,差异有统计学意义（χ²=4.666 7,P=0.031）。结论 ¹⁸F-FDG PET/CT对梗阻性黄疸的诊断具有重要价值,对临床治疗决策具有重要指导意义。     

18F-FDG PET/CT利尿延迟显像膀胱放射性廓清效果的影响因素

目的 探讨¹⁸F-FDG PET/CT利尿延迟显像膀胱放射性廓清效果的影响因素。方法 回顾性收集85例盆腔利尿延迟显像患者的PET/CT资料,测量膀胱常规及利尿延迟显像最大标准化摄取值（SUV_max）,记录延迟时间;分析常规显像膀胱SUV_max、呋塞米注射途径（静脉注射或肌内注射）、延迟时间、年龄、性别因素对利尿延迟显像膀胱SUV_max的影响。结果 根据呋塞米注射途径不同,分为静脉注射组（n=34）和肌内注射组（n=51）,2组利尿延迟显像膀胱SUV_max分别为3.10（2.60,3.45）和2.90（2.30,3.90）,差异无统计学意义（Z=-0.894,P=0.372）;延迟显像时间分别为¹⁸F-FDG注射后（215.00±30.03）min和（198.43±25.19）min,差异有统计学意义（t=-2.655,P=0.010）。2组间年龄差异无统计学意义（t=1.150,P=0.253）,2组中不同性别患者间延迟显像膀胱SUV_max差异均无统计学意义（P均>0.05）。静脉注射组和肌内注射组利尿延迟显像膀胱SUV_max与延迟时间和患者年龄均无明显相关性。结论 注射¹⁸F-FDG后充分水化、应用呋塞米利尿,约180 min行盆腔延迟显像能显著降低膀胱放射性,患者年龄、性别、呋塞米注射途径对于膀胱放射性廓清效果无明显影响。     

18F-FDG PET/CT双时相显像定性诊断肺占位性病变

目的 探讨¹⁸F-FDG PET/CT双时相显像定性诊断肺占位性病变的价值。方法 回顾性分析235例接受¹⁸F-FDG PET/CT双时相显像的肺内占位性病变患者的临床和影像学资料,按照病理结果分为良性病变组（n=80）和恶性病变组（n=155）。比较2组早期和延迟显像中肺部病灶的最大标准摄取值（SUV_max）,计算SUV_max变化率 ;以ROC曲线分析早期及延迟期肺部病灶SUV_max、RI对肺部恶性病变的诊断效能。结果 恶性病变组早期及延迟期SUV_max均大于良性病变组（P均<0.001）,且2组延迟期SUV_max均大于早期（P均<0.001）。恶性病变组RI大于良性病变组（P<0.001）。ROC曲线分析结果显示,早期SUV_max、延迟期SUV_max、RI及三者联合诊断肺部恶性病变的AUC分别为0.645、0.697、0.722及0.727（P均<0.05）。结论 ¹⁸F-FDG PET/CT双时相显像可用于定性诊断肺占位性病变。     

组织细胞坏死性淋巴结炎18F-FDG PET/CT表现

目的 观察组织细胞坏死性淋巴结炎（HNL）¹⁸F-FDG PET/CT表现。方法 回顾性分析11例经病理证实HNL患者的¹⁸F-FDG PET/CT及临床表现,分区域选取¹⁸F-FDG摄取最高的病变淋巴结54枚,分析其最大径、位置与最大标准摄取值（SUV_max）的相关性。结果 11例HNL中,7例受累淋巴结呈全身性分布,4例仅颈部和/或腋窝淋巴结受累;11例颈部淋巴结均受累,9例腋窝淋巴结受累;受累淋巴结呈卵圆形,最大短径均<2.30 cm,密度多均匀,且无融合趋势;¹⁸F-FDG PET/CT显像见不同程度放射性摄取,SUV_max为1.22~23.34,中位SUV_max为5.56（2.37,9.87）。8例发热患者中,6例中轴骨摄取高于肝脏。淋巴结最大短径、最大长径均与SUV_max呈低度正相关（r=0.496,P<0.001;r=0.347,P=0.010）,所在位置与SUV_max无明显相关（r=0.019,P=0.892）。结论 HNL于¹⁸F-FDG PET/CT显像主要表现为全身多发淋巴结轻、中度肿大,颈部及腋窝淋巴结多受累及代谢增高,伴或不伴中轴骨代谢增高。¹⁸F-FDG PET/CT可用于评估HNL患者全身淋巴结受累、判断疾病活动度及辅助活检定位。     

口服与静脉注射对18F-NaF PET/CT骨显像中靶/本底比值的影响

目的 探讨口服与注射¹⁸F-NaF两种给药途径对PET/CT骨显像中靶/本底比值的影响。方法 选取20例接受¹⁸F-NaF PET/CT骨显像检查的患者,于静脉注射¹⁸F-NaF后1 h（A组）行全身PET/CT采集;间隔1天后口服相同剂量¹⁸F-NaF后1 h（B组）及2 h（C组）再次行全身PET/CT采集。记录各部位骨骼和肌肉最大标准化摄取比值（SUV_max）,以骨骼为靶组织、邻近肌肉为本底,计算骨骼SUV_max/肌肉SUV_max值（靶/本底比值）。比较3组各部位SUV_max及靶/本底比值差异。结果 20例中,2例退出研究,最终18例患者完成所有检查。与A组相比,B组15例可见胃部显像剂分布,3例未见;C组胃部均未见显影,但10例可见肠道显像剂分布,余8例未见。3组间竖脊肌和双侧臀大肌SUV_max差异均无统计学意义（P均>0.05）;3组间其他部位本底SUV_max及各部位靶组织SUV_max、靶/本底比值差异均有统计学意义（P均<0.05）,其中C组及A组各指标均高于B组（P均<0.05）,而C组与A组差异均无统计学意义（P均>0.05）。结论 口服¹⁸F-NaF后2 h采集PET/CT的图像质量和靶/本底比值与静脉注射¹⁸F-NaF相似。口服给药可用于临床日常工作,尤其适用于难以接受静脉注射者。     

18F-FDG PET/CT联合MR胰胆管造影多模态显像诊断良恶性梗阻性黄疸

目的 探讨¹⁸F-FDG PET/CT联合MR胰胆管造影（MRCP）多模态显像对良恶性梗阻性黄疸的诊断价值。方法 回顾性分析57例梗阻性黄疸患者的PET/CT与MRCP资料,根据最终诊断分为恶性梗阻组（n=31）和良性梗阻组（n=26）,分析¹⁸F-FDG PET/CT与MRCP特征及多模态联合显像的诊断效能。结果 恶性梗阻组中,胰胆管中重度扩张13例（13/31,41.94%）,良性梗阻组中,胰胆管中重度扩张1例（1/26,3.85%）,差异有统计学意义（P=0.047）。恶性梗阻组病灶最大标准摄取值（SUV_max）为10.54±6.69,高于良性组（3.78±1.68;P<0.001）。¹⁸F-FDG PET/CT和MRCP诊断恶性梗阻性黄疸的灵敏度为90.32%（28/31）和61.29%（19/31）,差异有统计学意义（P=0.046）;特异度为84.62%（22/26）和76.92%（20/26）,差异无统计学意义（P=0.725）;准确率为87.72%（50/57）和68.42%（39/57）,差异有统计学意义（P=0.013）。¹⁸F-FDG PET/CT联合MRCP多模态显像诊断恶性梗阻性黄疸的灵敏度、特异度和准确率分别为96.77%（30/31）、88.46%（23/26）和92.98%（53/57）,与¹⁸F-FDG PET/CT比较差异均无统计学意义（P均>0.05）,与MRCP比较,灵敏度、准确率差异有统计学意义（P=0.002、0.002）,特异度差异无统计学意义（P=0.463）。¹⁸F-FDG PET/CT联合MRCP、¹⁸F-FDG PET/CT、MRCP诊断良恶性梗阻性黄疸与最终诊断结果的一致性Kappa值分别为0.858、0.752及0.375。结论 ¹⁸F-FDG PET/CT联合MRCP多模态显像有利于提高梗阻性黄疸的诊断准确率,对诊断与临床治疗决策具有重要指导意义。     

对比18F-NOTA-FAPI-04与18F-FDG PET/CT显像诊断腹膜转移癌

目的 对比¹⁸F-成纤维细胞激活蛋白抑制剂(FAPI)-04与¹⁸F-FDG PET/CT诊断腹膜转移癌(PC)的价值。方法 前瞻性纳入42例疑诊PC患者行全身¹⁸F-1,4,7-三氮杂环壬烷-N,N'',N″-三乙酸(NOTA)-FAPI-04和¹⁸F-FDG PET/CT检查,以病理学结果为金标准,比较2种显像的PC指数(PCI)、病灶最大标准摄取值(SUV_max)及靶-背景比(TBR)差异;绘制受试者工作特征曲线,评估2种显像诊断PC效能。结果 42例中,病理确诊31例PC。¹⁸F-NOTA-FAPI-04诊断PC的敏感度、特异度和准确率分别为93.55%、72.73%和88.10%,¹⁸F-FDG PET/CT分别为74.19%、54.55%和69.05%,前者的敏感度及准确率均高于后者(P均＜0.05);以前者所获PCI、所测PC的SUV_max、TBR均高于后者(P均＜0.001)。分别以2.31及2.52 为FAPI-SUV_max、FDG-SUV_max的截断值,¹⁸F-NOTA-FAPI-04及¹⁸F-FDG PET/CT诊断PC的曲线下面积(AUC)分别为0.839及0.630,差异有统计学意义(P=0.002);分别以1.60及0.73为FAPI-TBR、FDG-TBR的截断值,¹⁸F-NOTA-FAPI-04及¹⁸F-FDG PET/CT诊断PC的AUC分别为0.856及0.604,差异亦有统计学意义(P=0.005)。结论 ¹⁸F-NOTA-FAPI-04 PET/CT诊断PC较¹⁸F-FDG PET/CT更具优势。     

Radiosynthesis and Preclinical Evaluation of an α2A-Adrenoceptor Tracer Candidate, 6-[18F]Fluoro-marsanidine

Purpose

The α₂-adrenoceptors mediate many effects of norepinephrine and epinephrine, and participate in the regulation of neuronal, endocrine, cardiovascular, vegetative, and metabolic functions. Of the three receptor subtypes, only α_2A and α_2C are found in the brain in significant amounts. Subtype-selective positron emission tomography (PET) imaging of α₂-adrenoceptors has been limited to the α_2C subtype. Here, we report the synthesis of 6-[¹⁸F]fluoro-marsanidine, a subtype-selective PET tracer candidate for α_2A-adrenoceptors, and its preclinical evaluation in rats and mice.

Procedures

6-[¹⁸F]Fluoro-marsanidine was synthesized using electrophilic F-18 fluorination with [¹⁸F]Selectfluor bis(triflate). The tracer was evaluated in Sprague Dawley rats and in α_2A-knockout (KO) and wild-type (WT) mice for subtype selectivity. In vivo PET imaging and ex vivo brain autoradiography were performed to determine the tracer distribution in the brain. The specificity of the tracer for the target was determined by pretreatment with the subtype-non-selective α₂-agonist medetomidine. The peripheral biodistribution and extent of metabolism of 6-[¹⁸F]fluoro-marsanidine were also analyzed.

Results

6-[¹⁸F]Fluoro-marsanidine was synthesized with [¹⁸F]Selectfluor bis(triflate) in a radiochemical yield of 6.4?±?1.7 %. The molar activity was 3.1 to 26.6 GBq/μmol, and the radiochemical purity was >?99 %. In vivo studies in mice revealed lower uptake in the brains of α_2A-KO mice compared to WT mice. The results for selectivity were confirmed by ex vivo brain autoradiography. Blocking studies revealed reduced uptake in α_2A-adrenoceptor-rich brain regions in pretreated animals, demonstrating the specificity of the tracer. Metabolite analyses revealed very rapid metabolism of 6-[¹⁸F]fluoro-marsanidine with blood-brain barrier-permeable metabolites in both rats and mice.

Conclusion

6-[¹⁸F]Fluoro-marsanidine was synthesized and evaluated as a PET tracer candidate for brain α_2A-adrenoceptors. However, rapid metabolism, extensive presence of labeled metabolites in the brain, and high non-specific uptake in mouse and rat brain make 6-[¹⁸F]fluoro-marsanidine unsuitable for α_2A-adrenoceptor targeting in rodents in vivo.

     

Venous Admixture During Exercise in Sitting Position

Abstract

Introduction. The aim of this study was to establish a radio synthesis of ^99mTc-HYNIC-lactadherin for in vivo studies and to perform biodistribution analysis studies in mice, comparing ^99mTc-HYNIC-lactadherin to ^99mTc-HYNIC-annexin V. Methods. The radiochemical purity of ^99mTc-HYNIC-lactadherin was optimized by varying the amount of SnCl₂ in the synthesis. Furthermore, the need for bovine serum albumin (BSA) as a stabilizing agent was evaluated by following the stability by radiochemical purity measurement with and without the addition of BSA. A total of 24 mice were assigned to groups of 15 and nine mice, respectively. The animals were sacrificed at different time points; 10 min, 60 min, and 180 min. Results. The synthesis of ^99mTc-HYNIC-lactadherin for in vivo studies has been optimized to give a stable product without addition of BSA and with a radiochemical purity of more than 95%. Approximately 60% of the injected dose of ^99mTc-HYNIC-lactadherin was found in the liver and 4–5% could be assigned to kidneys. In contrast, ^99mTc-HYNIC-annexin V distributes with around 13% and 45% of the injected dose in liver and kidneys, respectively. Over the experimental period (10–180 min) only small distributional changes were observed for both probes. Conclusion. In conclusion, the biodistribution of ^99mTc-HYNIC-lactadherin, a potential new tracer for in vivo quantification of apoptosis, was evaluated. The small renal uptake of ^99mTc-HYNIC-lactadherin makes it possible to image apoptosis in the kidneys, but the high liver clearance may be a disadvantage during myocardial perfusion.     

基于七甲川菁构建并初步评估双模态PET/近红外荧光探针

目的 基于七甲川菁染料MHI148构建新型PET/近红外荧光(NIRF)双模态探针，并初步评估其用于肿瘤模型小鼠成像的能力。方法 采用双功能螯合剂DOTA修饰MHI148构建MHI148-DOTA,对其光物理、光热性能进行表征；以放射性核素⁶⁸Ga标记MHI148-DOTA,合成探针⁶⁸Ga-MHI148,测定其放射化学纯度及稳定性。建立小鼠乳腺癌4T1及人脑胶质母细胞瘤U-87MG皮下瘤模型，以⁶⁸Ga-MHI148探针对其进行小动物PET显像，观察成像效果及该探针在小鼠体内的生物分布。结果 MHI148-DOTA光物理及光热性能优异。以之构建的探针⁶⁸Ga-MHI148放射化学纯度>99%,稳定性良好；小动物PET成像可清晰显示肿瘤，肿瘤摄取随时间延长而逐渐升高，6 h时U-87MG及4T1肿瘤/肌肉摄取比值分别为4.55±0.20及8.08±2.26;⁶⁸Ga-MHI148小鼠体内主要分布于血液、肺、肝及肾脏。结论 成功构建的双模态⁶⁸Ga-M...     

罗萨伊-多尔夫曼病18F-FDG PET/CT表现

目的 观察罗萨伊-多尔夫曼病(RDD)¹⁸F-FDG PET/CT表现。方法 纳入6例活检病理确诊RDD患者，分析其¹⁸F-FDG PET/CT及其他常规影像学检查资料，观察RDD ¹⁸F-FDG PET/CT表现特点。结果 本组6例RDD中，1例为皮肤原发病变，3例为淋巴结内+结外病变，2例仅有淋巴结内病变；最常见的结外受累部位为骨(n=3),其次为鼻咽/鼻腔及鼻窦(n=2);PET/CT示其均呈FDG高摄取，最大标准摄取值为4.3～16.5。结论 RDD病灶¹⁸F-FDG PET/CT表现为FDG高摄取。     

Application of a Rapid, Simple, and Accurate Adenovirus-Based Method to Compare PET Reporter Gene/PET Reporter Probe Systems

Purpose

This study aims to use a simple, quantitative method to compare the HSV1sr39TK/¹⁸?F-FHBG PET reporter gene/PET reporter probe (PRG/PRP) system with PRGs derived from human nucleoside kinases.

Procedures

The same adenovirus vector is used to express alternative PRGs. Equal numbers of vectors are injected intravenously into mice. After PRP imaging, quantitative hepatic PET signals are normalized for transduction by measuring hepatic viral genomes.

Results

The same adenovirus vector was used to express equivalent amounts of HSV1sr39TK, mutant human thymidine kinase 2 (TK2-DM), and mutant human deoxycytidine kinase (dCK-A100VTM) in mouse liver. HSV1sr39TK expression was measured with ¹⁸?F-FHBG, TK2-DM and dCK-A100VTM with ¹⁸?F-L-FMAU. TK2-DM/¹⁸?F-L-FMAU and HSV1sr39TK/¹⁸?F-FHBG had equivalent sensitivities; dCK-A100VTM/¹⁸?F-L-FMAU was twice as sensitive as HSV1sr39TK/¹⁸?F-FHBG.

Conclusions

The human PRG/PRP sensitivities are comparable and/or better than HSV1sr39TK/¹⁸?F-FHBG. However, for clinical use, identification of the best PRP substrate for each enzyme, characterization of probe distribution, and consequences of overexpressing nucleoside kinases must be evaluated.     

Synthesis and Ex Vivo Autoradiographic Evaluation of Ethyl-��-d-galactopyranosyl-(1,4��)-2��-deoxy-2��-[18F]fluoro-��-d-glucopyranoside��A Novel Radioligand for Lactose-Binding Protein: Implications for Early Detection of Pancreatic Carcinomas with PET

Introduction

Previous studies demonstrated that the lactose-binding protein (hepatocellular carcinoma?Cintestine?Cpancreas and pancreatitis-associated proteins (HIP/PAP)) is upregulated >130 times in peritumoral pancreatic tissue as compared to normal pancreatic tissue. Therefore, we developed a new radiolabeled ligand of HIP/PAP, the ethyl-??-d-galactopyranosyl-(1,4??)-2??-deoxy-2??-[¹⁸F]fluoro-??-d-glucopyranoside (Et-[¹⁸F]FDL) for noninvasive imaging of pancreatic carcinoma using positron emission tomography and computerized tomography (PET/CT).

Methods

The novel precursor and radiolabeling methods for synthesis of Et-[¹⁸F]FDL produced no isomers; the average decay-corrected radiochemical yield was 68%, radiochemical purity >99%, and specific activity >74 GBq/µmol. The radioligand properties of Et-[¹⁸F]FDL were evaluated using an ex vivo autoradiography and immunohistochemistry in pancreatic tissue sections obtained from mice-bearing orthotopic pancreatic tumor xenografts.

Results and Discussion

Et-[¹⁸F]FDL binding to peritumoral pancreatic tissue sections strongly correlated with HIP/PAP expression (r?=?0.81) and could be completely blocked by treatment with 1 mM lactose.

Conclusion

These results suggest that Et-[¹⁸F]FDL is a promising agent which should be evaluated for detection of early pancreatic carcinomas by PET/CT imaging.     

核素凋亡显像评价小鼠肝细胞凋亡

目的将凋亡显像剂99mTc-HYNIC-Annexin V用于肝细胞凋亡小鼠动物模型显像,以评价其用于显示凋亡的可行性。方法通过双功能螯合剂HYNIC偶联Annexin V后99mTc标记,鉴定99mTc-HYNIC-Annexin V标记率、放化纯和稳定性。取正常昆明小鼠随机分为正常对照组及应用anti-Fas抗体处理后肝细胞凋亡组,注射显像剂后不同时间行SPECT显像,考察显像剂在小鼠体内分布及排泄情况,应用感兴趣区(region of interest,ROI)技术比较正常组及凋亡组显像图像中肝脏/前臂比值。取两组动物肝脏组织HE染色进行病理学分析,Hoechst33258染色检测凋亡。结果99mTc-HYNIC-Annexin V标记率可达(96.32±2.08)%,放化纯度达到(96.90±2.27)%,标记物体外稳定。正常小鼠体内显像剂从肾脏排泄,肝脏仅有少量分布。凋亡组肝脏有明显显像剂浓聚,不同时间下肝脏/前臂的比值均高于正常小鼠。HE染色及Hoechst33258染色提示凋亡组有大量肝细胞凋亡。结论研究制备的凋亡显像剂99mTc-HYNIC-Annexin V可以活体显示发生凋亡的肝脏,用于在体凋亡显像,有望成为一种有良好临床应用前景的凋亡显像剂。     

18F-FDG PET/CT诊断多发性骨髓瘤

目的 探讨18F-FDG PET/CT对多发性骨髓瘤(MM)的诊断价值.方法 MM患者20例,均于治疗前进行18F-FDG PET/CT全身显像.所有PET、CT及PET/CT融合图像均通过融合软件进行帧对帧对比分析.肿瘤病灶根据穿刺活组织病理学检查、多种影像学检查和临床随访结果 诊断.结果 19例18F-FDG PET/CT检出阳性病灶(95.00%),SUV为2.81±0.98(1.30～6.00), 共检出病灶303处,其中PET有222处表现为18F-FDG摄取增高(73.27%),CT检出268处灶状溶骨性改变(88.45%).PET和CT同时检出的病灶为187处(61.72%);PET检出而同机CT未检出的病灶35处(11.55%);同机CT检出而PET未检出病灶81处(26.73%).结论 18F-FDG PET/CT对于MM的诊断及评价全身累及范围具有一定价值.     

(2S, 4R)-4-[18F]Fluoroglutamine for In vivo PET Imaging of Glioma Xenografts in Mice: an Evaluation of Multiple Pharmacokinetic Models

Purpose

The glutamine analogue (2S, 4R)-4-[¹⁸F]fluoroglutamine ([¹⁸F]FGln) was investigated to further characterize its pharmacokinetics and acquire in vivo positron emission tomography (PET) images of separate orthotopic and subcutaneous glioma xenografts in mice.

Procedures

[¹⁸F]FGln was synthesized at a high radiochemical purity as analyzed by high-performance liquid chromatography. An orthotopic model was created by injecting luciferase-expressing patient-derived BT3 glioma cells into the right hemisphere of BALB/cOlaHsd-Foxn1^nu mouse brains (tumor growth monitored via in vivo bioluminescence), the subcutaneous model by injecting rat BT4C glioma cells into the flank and neck regions of Foxn1^nu/nu mice. Dynamic PET images were acquired after injecting 10–12 MBq of the tracer into mouse tail veins. Animals were sacrificed 63 min after tracer injection, and ex vivo biodistributions were measured. Tumors and whole brains (with tumors) were cryosectioned, autoradiographed, and stained with hematoxylin-eosin. All images were analyzed with CARIMAS software. Blood sampling of 6 Foxn1^nu/nu and 6 C57BL/6J mice was performed after 9–14 MBq of tracer was injected at time points between 5 and 60 min then assayed for erythrocyte uptake, plasma protein binding, and plasma parent-fraction of radioactivity to correct PET image-derived whole-blood radioactivity and apply the data to multiple pharmacokinetic models.

Results

Orthotopic human glioma xenografts displayed PET image tumor-to-healthy brain region ratio of 3.6 and 4.8 while subcutaneously xenografted BT4C gliomas displayed (n?=?12) a tumor-to-muscle (flank) ratio of 1.9?±?0.7 (range 1.3–3.4). Using PET image-derived blood radioactivity corrected by population-based stability analyses, tumor uptake pharmacokinetics fit Logan and Yokoi modeling for reversible uptake.

Conclusions

The results reinforce that [¹⁸F]FGln has preferential uptake in glioma tissue versus that of corresponding healthy tissue and fits well with reversible uptake models.

     

原发性干燥综合征继发肺淀粉样变性影像学表现以及文献复习

目的 结合回顾文献分析原发性干燥综合征（pSS）继发肺淀粉样变性（PA）的CT及¹⁸F-FDG PET/CT表现。方法 回顾性收集4例经病理证实的pSS继发PA患者,均接受胸部CT检查,其中1例接受全身¹⁸F-FDG PET/CT检查;结合文献分析pSS继发PA的CT及¹⁸F-FDG PET/CT表现。结果 4例胸部CT均表现为双肺多发结节或团块,病灶最大径3~36 mm、中位最大径13 mm,CT值15~410 HU、中位CT值65 HU,部分伴钙化（3/4）;并均见肺囊腔样病变（4/4）。¹⁸F-FDG PET/CT示部分结节¹⁸F-FDG摄取轻度升高。结论 pSS继发PA的CT表现具有一定特征性;结合¹⁸F-FDG PET/CT有助于与肿瘤性病变相鉴别。