符合线路SPECT 3D采集的可行性研究

目的 分析符合线路SPECT（GE Millennium VH with Hawkeye）三维（3D）采集的可行性.方法 采用充满^18F溶液的圆柱体模型,用符合线路SPECT仪对模型分别行用隔栅（二维,2D）和没有隔栅的探头护板（3D）2种方式图像采集.首先进行X线透射扫描约10 min,获得横断层透射影像,然后进行符合探测采集10 min,获得发射扫描数据.根据横断层透射影像生成非均匀衰减校正图,用有序子集最大期望值迭代法（OSEM）加衰减校正进行发射影像重建.对获得的模型横断面图像进行处理,得到对比度、均匀性、空间分辨率、符合计数率等指标.结果 与2D采集相比,3D采集的单光子计数率提高2倍以上,符合计数率提高4倍以上,其“热区”对比度有所降低,但幅度较小,均匀性降低29%,空间分辨率差异无显著性.结论 3D符合采集可减少临床采集时间,其图像质量在正常剂量条件下与2D采集相比无明显降低,但在低剂量条件下,3D图像质量优于2D图像.     

肺部病变18F-FDGSPECT符合线路显像

目的:探讨18F-FDG SPECT符合线路显像对肺部病变的定性诊断价值。材料和方法:用双探头SPECT符合线路对肺部病变患者进行18F-FDG肿瘤代谢显像,分析检查结果并与CT进行比较。结果:48例肺部病变患者18F-FDG显像诊断结果为真阳性37例,真阴性7例,假阳性3例和假阴性1例。其诊断的准确率、灵敏度和特异性分别为91.7％,97.4％和70％。诊断准确率显著高于CT检查。结论:18F-FDG SPECT符合线路显像对肺部病变具有较高的定性诊断价值。     

良恶性肿瘤18F-FDG符合线路显像的临床价值

目的 评价18F-FDG符合线路显像检测良恶性肿瘤的诊断价值.方法 回顾性分析135例病变性质不明患者的18F-FDG符合线路显像结果,并与常规影像学检查结果进行对比分析.病变的确诊依据手术病理检查和临床随诊.结果 135例患者经病理学检查及随访结果最终确诊为恶性病变者86例(病灶数:95个),良性病变者49例(病灶数...     

肺良性病变~(18)F-FDG符合线路SPECT显像

目的　通过符合线路SPECT显像探讨肺部良性病变中18F 脱氧葡萄糖 (FDG)的摄取情况。方法　用双探头符合线路SPECT显像对肺部病变患者进行检查 ,观察各种病变摄取18F FDG的情况及其影像特征。结果　① 2 8例肺结核患者中 ,19例 (6 8% )显像阴性 ,9例 (32 % )显像阳性 ,其靶/非靶 (T/N)值为 1 7± 1 2 ,而肺癌的T/N值为 4 1± 2 4,两者差异有显著性。显像阳性的 9例结核菌素 (PPD)皮肤试验红斑平均直径为 16 2 (12～ 2 2 )mm ,显像阴性的 7例为 8 6 (0～ 15 )mm ,两者差异有显著性。② 8例结节病中 5例显像阳性 ,为新发现的活动期病例 ;3例显像阴性 ,为经治疗好转者。③炎症患者 18例 ,其中隐球菌病、支原体肺炎、霉菌病、机化性肺炎、肺脓肿及细菌性肺炎各 1例显像阳性。结论　肺良性病变18F FDG显像也会产生阳性。对显像特征进行分析能提高对肺癌诊断的特异性 ,也为诊治良性病变提供一些新思路。     

双探头符合线路SPECT正电子显像衰减校正实验研究

目的 用Jaszczak模型及心肌模型检测及评价SPECT和正电子符合探测显像衰减校正在肿瘤和心肌显像中的应用效果.方法 用Jaszczak模型充满18F-脱氧葡萄糖(FDG)溶液,充分混匀,分别在Vertex Plus机型和Hawkeye机型上做模型图像的采集并进行图像重建.结果 Vertex Plus衰减校正后的图像质量明显改善,周边和深部的计数之差减少,深部的计数得到补偿.校正后的图像可以发现直径为9 mm的"冷"区,而7 mm的"冷"区则难以辨认,"热"区可以分辨到6 mm.Hawkeye衰减校正后的圆形"冷"区有较大的改善,校正前对直径在12 mm以下的"冷"区都无法显示,中央的"冷"区几乎与本底相似,难以分辨,周边的放射性与中央部分的放射性计数差距较大.校正后的图像可以发现5个"冷"区,而7 mm的"冷"区则难以辨认.结论 衰减校正的模型实验显示用137CS作为穿透射线方法的校正效果优于Hawkeye X线球管,不仅明显改变图像质量,而且可以明显改善空间分辨率,在"冷"区可以显示到直径9 mm,而"热"区则可以显示到6 mm.     

18F-FDG符合线路显像在乳腺癌诊断中的初步应用

目的研究18F-FDGSPECT/CT符合线路正电子显像在鉴别乳腺肿块性质和乳腺癌术前淋巴结转移分期中的应用价值。方法22例有乳腺肿块的女性患者行SPECT/CT符合线路18F-FDG显像,患者禁食6h以上,肘静脉注射18F-FDG185MBq～296MBq。静注60min后开始发射和X线CT透射扫描,然后进行符合线路PET连续采集30min。图像经X线衰减校正和有序子集最大期望值法(COSEM)叠代重建后,得到横断面、冠状面、矢状面三维断层图像及CT与FDGSPECT的融合图像。结果22例患者均通过手术切除治疗并获得病理结果。其中,乳腺癌16例,乳腺良性肿瘤6例。FDGSPECT诊断乳腺癌的敏感度、特异性和准确度分别是93.75%、100%和95.45%,明显高于乳腺X射线摄片。16例乳腺癌患者,15例FDGSPECT分期与临床手术分期一致。利用SPECT/CT仪所配备的定位CT,15例乳腺癌患者的病灶可准确定位。结论SPECT/CT符合线路18F-FDG显像在乳腺癌的诊断、转移灶定位以及临床分期方面具有重要的临床应用价值。     

双探头符合线路SPECT正电子显像衰减校正实验研究

Objective The photons from the body would be attenuated in their intensity by the soft tissue before they reach the detectors. Some of them lost more intensity than others when coming from the deeper body. Attenuation of the photons would distort the image, affect the image quality, and may lead to misdiagnosis. In this research the X-ray and γ-ray were used as transmission resources for accurate assess-ment of attenuation in each part of the body. The transmission data was used to correct the emission data from the body. Iteration algorithm was used for the reconstruction of attenuation corrected tomography ima-ges. Evaluate the efficacy of attenuation correction in duel head hybrid SPECT/coincidence PET systems (SPECT/PET) and SPECT using both the Jaszczak and the myocardial phantoms. Methods For PET phantom study, the Jaszczak phantom was filled with the aqueous solution of 18F-fluorodeoxyglucose (FDG) and was scanned with two hybrid SPECT/coincidence PET systems respectively (Vertex Plus, Netherlands Philips ADAC Company and Hawkeye, USA GE Company). The PET images were acquired and reconstruc-ted. Results The "cold" lesion, which the diameter was less than 12 mm of uncorrected image, could not be identified. But it, after correction, diameter 9 mm, would be recognized clearly, less than 7 mm would not be distinguished. Noncorrected image could only identify "hot" lesions which the diameter were 9, 12, 14, 18, 22 and 38 mm, while in the corrected image, not only it was much better, but also the "hot" le-sion of 6 mm was distinguished. In Hawkeye, the same situation, the corrected image of was improved obvi-ously; the disparity of counts between surrounding and deep center less, and the counts in deep center were compensated. There were only 3 round " cold" lesions could be recognized, the diameter: 14, 18 and 20 mm; all of them which diameter were less than 12 mm could not be distinguished. One in the center was al-most as background, and could not be identified. The radioactive accounts of surrounding and center were quite different. The corrected image 5 "cold" lesions could be found, 9, 12, 14, 18 and 20 mm, but7 mm could not be found. The noncorrected image, only 12, 14, 18, 22 and 38 mm " hot" lesions could be found, and by the surrounding, there was an arc shape "hot" lesion. But it could distinguish 9, 12, 14, 18, 22 and 38 mm "hot" lesions on the corrected image, and the image was much better than noncorrected one. Conclusions The corrected image of Vertex Plus was improved obviously with the disparity of counts between surrounding and deep center less, and the counts in deep center was compensated. The result of at-tenuation with phantom showed that 137Cs was better than CT in both image quality and spatial resolution.     

双探头符合线路SPECT正电子显像衰减校正实验研究

Objective The photons from the body would be attenuated in their intensity by the soft tissue before they reach the detectors. Some of them lost more intensity than others when coming from the deeper body. Attenuation of the photons would distort the image, affect the image quality, and may lead to misdiagnosis. In this research the X-ray and γ-ray were used as transmission resources for accurate assess-ment of attenuation in each part of the body. The transmission data was used to correct the emission data from the body. Iteration algorithm was used for the reconstruction of attenuation corrected tomography ima-ges. Evaluate the efficacy of attenuation correction in duel head hybrid SPECT/coincidence PET systems (SPECT/PET) and SPECT using both the Jaszczak and the myocardial phantoms. Methods For PET phantom study, the Jaszczak phantom was filled with the aqueous solution of 18F-fluorodeoxyglucose (FDG) and was scanned with two hybrid SPECT/coincidence PET systems respectively (Vertex Plus, Netherlands Philips ADAC Company and Hawkeye, USA GE Company). The PET images were acquired and reconstruc-ted. Results The "cold" lesion, which the diameter was less than 12 mm of uncorrected image, could not be identified. But it, after correction, diameter 9 mm, would be recognized clearly, less than 7 mm would not be distinguished. Noncorrected image could only identify "hot" lesions which the diameter were 9, 12, 14, 18, 22 and 38 mm, while in the corrected image, not only it was much better, but also the "hot" le-sion of 6 mm was distinguished. In Hawkeye, the same situation, the corrected image of was improved obvi-ously; the disparity of counts between surrounding and deep center less, and the counts in deep center were compensated. There were only 3 round " cold" lesions could be recognized, the diameter: 14, 18 and 20 mm; all of them which diameter were less than 12 mm could not be distinguished. One in the center was al-most as background, and could not be identified. The radioactive accounts of surrounding and center were quite different. The corrected image 5 "cold" lesions could be found, 9, 12, 14, 18 and 20 mm, but7 mm could not be found. The noncorrected image, only 12, 14, 18, 22 and 38 mm " hot" lesions could be found, and by the surrounding, there was an arc shape "hot" lesion. But it could distinguish 9, 12, 14, 18, 22 and 38 mm "hot" lesions on the corrected image, and the image was much better than noncorrected one. Conclusions The corrected image of Vertex Plus was improved obviously with the disparity of counts between surrounding and deep center less, and the counts in deep center was compensated. The result of at-tenuation with phantom showed that 137Cs was better than CT in both image quality and spatial resolution.     

双探头符合线路SPECT正电子显像衰减校正实验研究

Objective The photons from the body would be attenuated in their intensity by the soft tissue before they reach the detectors. Some of them lost more intensity than others when coming from the deeper body. Attenuation of the photons would distort the image, affect the image quality, and may lead to misdiagnosis. In this research the X-ray and γ-ray were used as transmission resources for accurate assess-ment of attenuation in each part of the body. The transmission data was used to correct the emission data from the body. Iteration algorithm was used for the reconstruction of attenuation corrected tomography ima-ges. Evaluate the efficacy of attenuation correction in duel head hybrid SPECT/coincidence PET systems (SPECT/PET) and SPECT using both the Jaszczak and the myocardial phantoms. Methods For PET phantom study, the Jaszczak phantom was filled with the aqueous solution of 18F-fluorodeoxyglucose (FDG) and was scanned with two hybrid SPECT/coincidence PET systems respectively (Vertex Plus, Netherlands Philips ADAC Company and Hawkeye, USA GE Company). The PET images were acquired and reconstruc-ted. Results The "cold" lesion, which the diameter was less than 12 mm of uncorrected image, could not be identified. But it, after correction, diameter 9 mm, would be recognized clearly, less than 7 mm would not be distinguished. Noncorrected image could only identify "hot" lesions which the diameter were 9, 12, 14, 18, 22 and 38 mm, while in the corrected image, not only it was much better, but also the "hot" le-sion of 6 mm was distinguished. In Hawkeye, the same situation, the corrected image of was improved obvi-ously; the disparity of counts between surrounding and deep center less, and the counts in deep center were compensated. There were only 3 round " cold" lesions could be recognized, the diameter: 14, 18 and 20 mm; all of them which diameter were less than 12 mm could not be distinguished. One in the center was al-most as background, and could not be identified. The radioactive accounts of surrounding and center were quite different. The corrected image 5 "cold" lesions could be found, 9, 12, 14, 18 and 20 mm, but7 mm could not be found. The noncorrected image, only 12, 14, 18, 22 and 38 mm " hot" lesions could be found, and by the surrounding, there was an arc shape "hot" lesion. But it could distinguish 9, 12, 14, 18, 22 and 38 mm "hot" lesions on the corrected image, and the image was much better than noncorrected one. Conclusions The corrected image of Vertex Plus was improved obviously with the disparity of counts between surrounding and deep center less, and the counts in deep center was compensated. The result of at-tenuation with phantom showed that 137Cs was better than CT in both image quality and spatial resolution.     

双探头符合线路SPECT正电子显像衰减校正实验研究

Objective The photons from the body would be attenuated in their intensity by the soft tissue before they reach the detectors. Some of them lost more intensity than others when coming from the deeper body. Attenuation of the photons would distort the image, affect the image quality, and may lead to misdiagnosis. In this research the X-ray and γ-ray were used as transmission resources for accurate assess-ment of attenuation in each part of the body. The transmission data was used to correct the emission data from the body. Iteration algorithm was used for the reconstruction of attenuation corrected tomography ima-ges. Evaluate the efficacy of attenuation correction in duel head hybrid SPECT/coincidence PET systems (SPECT/PET) and SPECT using both the Jaszczak and the myocardial phantoms. Methods For PET phantom study, the Jaszczak phantom was filled with the aqueous solution of 18F-fluorodeoxyglucose (FDG) and was scanned with two hybrid SPECT/coincidence PET systems respectively (Vertex Plus, Netherlands Philips ADAC Company and Hawkeye, USA GE Company). The PET images were acquired and reconstruc-ted. Results The "cold" lesion, which the diameter was less than 12 mm of uncorrected image, could not be identified. But it, after correction, diameter 9 mm, would be recognized clearly, less than 7 mm would not be distinguished. Noncorrected image could only identify "hot" lesions which the diameter were 9, 12, 14, 18, 22 and 38 mm, while in the corrected image, not only it was much better, but also the "hot" le-sion of 6 mm was distinguished. In Hawkeye, the same situation, the corrected image of was improved obvi-ously; the disparity of counts between surrounding and deep center less, and the counts in deep center were compensated. There were only 3 round " cold" lesions could be recognized, the diameter: 14, 18 and 20 mm; all of them which diameter were less than 12 mm could not be distinguished. One in the center was al-most as background, and could not be identified. The radioactive accounts of surrounding and center were quite different. The corrected image 5 "cold" lesions could be found, 9, 12, 14, 18 and 20 mm, but7 mm could not be found. The noncorrected image, only 12, 14, 18, 22 and 38 mm " hot" lesions could be found, and by the surrounding, there was an arc shape "hot" lesion. But it could distinguish 9, 12, 14, 18, 22 and 38 mm "hot" lesions on the corrected image, and the image was much better than noncorrected one. Conclusions The corrected image of Vertex Plus was improved obviously with the disparity of counts between surrounding and deep center less, and the counts in deep center was compensated. The result of at-tenuation with phantom showed that 137Cs was better than CT in both image quality and spatial resolution.     

18F-FDG符合线路显像对食管癌术后复发转移的诊断价值

目的 探讨^18F-脱氧葡萄糖（FDG）符合线路显像对食管癌术后复发转移的诊断价值。方法 对29例临床怀疑复发转移的食管鳞状细胞癌术后患者行^18F-FDG符合线路显像，计算其诊断复发转移灶的灵敏度、特异性和准确性，并与CT诊断结果比较。结果 29例患者中符合线路显像真阳性19例，真阴性6例，假阳性、假阴性各2例，其诊断食管癌术后复发转移的灵敏度、特异性和准确性分别为90．5％（19／21例）、75．0％（6／8例）和86．2％（25／29例）；而CT诊断的灵敏度、特异性和准确性分别为71．4％（15／21例）、87．5％（7／8例）和75．9％（22／29例）。在符合线路显像与CT检查均阳性的13例患者中，CT检出病灶20个；而符合线路显像检出27个，比CT多检出的病灶包括食管癌复发，锁骨上、纵隔和肺门淋巴结及骨转移。结论 ^18F-FDG符合线路显像对食管癌术后复发转移的诊断具有较高的临床价值，尤其在临床疑有复发转移而常规影像学检查阴性时有重要意义。     

双探头符合探测图像的噪声分析

目的分析双探头符合探测图像的噪声成分。方法采用Hawkeye双探头SPECT仪及东芝模型，对7种活度进行采集重建图像，测量^18F-脱氧葡萄糖(FDG)均匀分布区域像素均值及标准差，对数据进行曲线拟合。结果噪声分为3个成分：成分1与信号强度成正比，由随机符合造成；成分2与信号强度的平方根成正比，由放射性统计涨落造成；成分3与信号强度无关。图像的信噪比平方与计数成二次．线性关系，随计数增加信噪比增加，但其速度逐渐缓慢，达最大值后开始降低。结论符合探测图像噪声的平方与计数成二次一线性关系。与单光子显像相比，其噪声中增加了与信号强度成正比的随机符合噪声部分。     

衰减校正在18F-FDG SPECT显像中的价值

目的评价衰减校正(AC)在18F-脱氧葡萄糖(FDG) SPECT显像中的临床价值.方法对病理检查证实的36例恶性肿瘤和4例良性肿物患者进行18F-FDG SPECT显像,进行迭代法重建AC和非衰减校正(NAC),并计算两者的肿瘤与本底比值(T/B).28例正常人进行了胸部18F-FDG SPECT显像.将左室心肌分为9个节段,用5分法(0正常;1分轻度减少;2分中度减少;3分明显减少;4分缺损)对AC与NAC图像的各心肌节段进行评分.结果 36例恶性肿瘤患者中34例AC与NAC均诊断为恶性,两者均检出55个病灶,2例(6%)AC与NAC均为假阴性,4例良性病变AC与NAC均为阴性.肺部肿瘤T/B在AC后增加(P<0.01),肺外肿瘤T/B AC后降低(P<0.05),不同部位肿瘤T/B在AC与NAC间呈显著正相关(P<0.01).AC对病变的解剖位置、周围组织受累情况及深部病变显示更加清晰.全部28例心肌显像者的左室前、后间壁,下、后壁在NAC影像均出现明显放射性衰减伪影,AC后显著改善(P<0.01);17例(60.7%)心尖、6例(21.4%)前壁心尖段放射性分布在AC后有轻度减低(P<0.01);AC后平均左室总分由NAC时的10.82±2.14下降为3.64±2.23(P<0.01).结论 AC虽未能增加肿瘤检出率,但可更清晰地显示肿瘤的位置、范围以及深部病灶,并可显著改善心肌衰减伪影,具有一定的临床价值.     

衰减校正在18F-FDG符合线路显像中的价值

目的评价衰减校正(AC)在^18F-脱氧葡萄糖(FDG)符合线路显像中的价值。方法对圆柱体模型行^18F-FDG符合线路显像，进行AC和非衰减校正(NAC)图像视觉分析和半定量分析比较。结果AC图像在均匀度和空间分辨率等方面均优于NAC图像，并消除了NAC图像中的形变现象。结论AC可明显改善图像质量。     

符合线路显像与PET显像中SUV的比较研究

目的比较符合线路显像标准摄取值(SUV)与PET显像的SUV。方法用双探头符合显像仪及PET对模型显像，分别采用不同的重建算法重建，测定图像上热灶的SUV。结果对直径小于30mm热灶，相同大小时，PET、得到的SUV高于符合线路显像；无论对PET还是符合线路显像，随热灶大小增加SUV增加；SUV与重建算法有关；选取的感兴趣区(ROI)越大，获得的SUV越小；由PET图像获得的热灶SUV可见，当热灶大于2倍的系统分辨率时，SUCmax接近热灶的真实值(SUVmax)。结论符合线路显像的SUV低于PET显像；病灶大小、重建算法、ROI大小均影响SUV。     

18F-FDG符合线路显像在胃肠间质瘤诊治中的价值

目的 探讨18 F-FDG符合线路显像在胃肠间质瘤(GIST)良恶性鉴别及其治疗后复发监测的价值.方法 回顾性分析22例经免疫组织化学证实为GIST患者,共行28例次18F-FDG符合线路显像.13例术前显像,9例术后显像,9例中2例临床予药物治疗过程中分别行4次显像.用ROI技术计算良恶性病变/正常组织放射性比值(T/B).术前良恶性病例组间T/B比较采用两样本比较t检验,并将T/B与GIST危险度分级进行等级相关分析.结果 13例术前显像呈高摄取者10例(T/B＞2.0),低摄取3例(T/B≤2.0);病理检查证实:18F-FDG高摄取10例均为恶性(高度或中度危险),低摄取良性3例(极低或低危险度).恶性组患者T/B为5.050±2.315,与良性患者的1.533±0.503相比,差异有统计学意义(t=4.464,P＜0.001);T/B与GIST危险度分级间存在相关性(r=0.819,P＜0.01);9例术后显像者复发或转移5例,FDG均呈高摄取,T/B均＞2.2.结论 18F-FDG符合线路显像在原发GIST良恶性的鉴别及治疗后复发或转移灶的监测中有一定应用价值.     

^18F-FDG符合线路显像在胸腺上皮肿瘤诊断中的应用价值

目的探讨^18F-脱氧葡萄糖（FDG）符合线路显像在胸腺上皮肿瘤（TET）诊断中的价值。方法回顾性分析37例TET患者的^18F—FDG符合线路显像结果,图像分析采用视觉分析及半定量方法[肿瘤／正常肺组织放射性比值（TLR）]。按WHO TET病理学分类结果将患者分成3组（高生存率组,包括A、AB、B1型;中生存率组,包括B2、B3型;低生存率组,包括胸腺癌）;同时将^18F—FDG显像结果与增强CT影像进行对比,TLR与免疫组织化学检查所测Ki67标记指数（细胞增殖指标）进行相关性分析。组间TLR比较采用方差分析。结果（1）^18F—FDG符合线路显像阳性率91．9％（34／37）;（2）3个不同生存率组TLR间差异有统计学意义（高、中、低生存率组TLR依次为：1．42±0．27,2．13±0．74,3．00±1．19,F=9．99,P〈0．05）;（3）TLR与Ki67标记指数有明显相关性（r=0．613,P=0．002）;（4）^18F-FDG显像发现2例增强CT未发现的病灶,病灶分别位于前胸壁和右锁骨上淋巴结;（5）共有4例伴发重症肌无力。结论^18F—FDG符合线路显像有助于WHO TET病理学分类和发现更多的TET侵犯、转移灶;可以用^18F—FDG在TET的浓聚程度反映细胞的增殖活力。     

胸部模型~(18)F-FDG双探头符合显像实验研究

目的　评价18F 脱氧葡萄糖 (FDG)双探头符合线路显像对肺部结节的探测效果。方法用胸部模型作双探头符合显像。结果　符合计数率足够时 ,衰减校正 (AC)和非衰减校正 (NOAC)均能见到≥ 11mm的球体 ,AC的靶 /本底 (T/B)比值小于NOAC ,大结节的T/B值比小结节高。增大T/B值则结节的分辨率提高。随着符合计数率的减低 ,NOAC仅能发现≥ 15mm的球体 ,而AC能发现所有的球体。结论　符合计数率适当时产生的图像最佳 ,AC比NOAC能发现更小的结节。