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121.
Preliminary assessment of fluorine-18 fluorodeoxyglucose positron mission tomography in patients with bladder cancer 总被引:5,自引:1,他引:4
Shigeru Kosuda Paul V. Kison Robert Greenough H. Barton Grossman Richard L. Wahl 《European journal of nuclear medicine and molecular imaging》1997,24(6):615-620
The purpose of this study was to assess the feasibility of imaging of bladder cancer with fluorine-18 fluorodeoxyglucose positron emission tomography (FDG-PET) scanning. We studied 12 patients with histologically proven bladder cancer who had undergone surgical procedures and/or radiotherapy. Retrograde irrigation of the urinary bladder with 1000–3710 ml saline was performed during nine of the studies. Dynamic and static PET images were obtained, and standardized uptake value images were reconstructed. FDG-PET scanning was true-positive in eight patients (66.7%), but false-negative in four (33.3%). Of 20 organs with tumor mass lesions confirmed pathologically or clinically, 16 (80%) were detected by FDG-PET scanning. FDG-PET scanning detected all of 17 distant metastatic lesions and two of three proven regional lymph node metastases. FDG-PET was also capable of differentiating viable recurrent bladder cancer from radiation-induced alterations in two patients. In conclusion, these preliminary data indicate the feasibility of FDG-PET imaging in patients with bladder cancer, although a major remaining pitfall is intense FDG accumulation in the urine.
Present address: Department of Radiology, National Defense Medical College, 3-2 Namiki, Tokorozawa 359, Japan 相似文献
122.
颞下颌关节的三维有限元法研究 总被引:1,自引:0,他引:1
本研究利用颞下颌关节CT扫描资料和计算机图像分析处理技术以及三维有限元方法相结合建立了髁状突的三维有限元模型,结果表明,此方法在技术上是可行的并将有助于颞下颌关节的临床和基础研究。 相似文献
123.
MRI demonstration and CT correlation of the brain in patients with idiopathic intracerebral calcification 总被引:2,自引:0,他引:2
Twenty-two patients aged 36–63 years were diagnosed as having Fahr's syndrome on the basis of the presence on CT of unexpected extensive calcification of the basal ganglia. Even when associated with calcification of other brain areas, the main diagnostic criterion remained basal ganglia calcification larger than 800 mm2. Normal values of parathormone, serum calcium and phosphorus excluded hypercalcaemia and hypoparathyroidism. Mitochondrial CNS disease was excluded clinically. MRI and repeated CT and neurological examination were performed in all of the patients. The patients were divided into two groups: neurologically asymptomatic (group 1) and neurologically symptomatic (group 2). T2-weighted sequences demonstrated hyperintense areas in all of the patients involving the white and the grey matter of the brain. In group 1 the hyperintense lesions were significantly smaller than in group 2. The neurological symptoms correlated better with the hyperintensities on T2-weighted MR images than with the calcification demonstrated on CT. Hyperintensities in T2-weighted MRI and the areas shown by CT to have calcification had different locations. In 15 patients with dementia, the white matter of the entire centrum semiovale was bilaterally hyperintense. In another 3 patients with hemiparesis, hyperintense areas in the internal capsule, contralateral to the side of hemiparesis, were demonstrated in the T2-weighted sequence. The hyperintense T2 signals may reflect a slowly progressive, metabolic or inflammatory process in the brain which subsequently calcifies and are probably responsible for the neurological deficit observed. 相似文献
124.
Fluorine-18-fluorodeoxyglucose positron emission tomography for preoperative parathyroid imaging in primary hyperparathyroidism 总被引:5,自引:3,他引:2
Pierre Melon Andre Luxen Etienne Hamoir Michel Meurisse 《European journal of nuclear medicine and molecular imaging》1995,22(6):556-558
Fluorine-18 fluorodeoxyglucose (FDG) positron emission tomography (PET) imaging was performed in seven consecutive patients with primary hyperparathyroidism to preoperatively locate parathyroid adenomas. Foci of FDG accumulation corresponding to abnormal parathyroid tissue were observed in two out of nine surgically excised parathyroid adenomas. It was concluded that FDG PET imaging demonstrated a too low sensitivity for systematic preoperative detection and localization of parathyroid glands causing primary hyperparathyroidism. 相似文献
125.
DANCHIN N.; HAOUZI A.; AMOR M.; KARCHER G.; BRUNOTTE F.; JUILLIERE Y.; CUILLIERE M.; VILLEMOT J.P.; PERNOT C.; GILGENKRANTZ J.M.; BERTRAND A.; CHERRIER F. 《European heart journal》1988,9(4):454-457
Of 46 consecutive patients who underwent percutaneous transluminalcoronary angioplasty (PTCA) from April 1980 to August 1982 andwho had a satisfactory angiographic result six months later,one died of cancer and 41 had a detailed evaluation with exercisesingle-photon emission computed tomography (SPECT, 40 patients)or repeat coronary angiography (one patient), 4878 monthsafter the procedure. During follow-up, two patients had recurrentangina due to progression of coronary artery disease requiringa second PTCA procedure of another coronary artery; one of themlater had a limited myocardial infarction in an area suppliedby the vessel initially dilated. At follow-up, only one patienthad definite angina. All but one patient had a negative exercisetest. Myocardial perfusion during exercise in the PTCA-relatedarea, assessed by SPECT, was normal in 90% of the patients andshowed a limited defect due to reversible ischaemia in the remainingfour (10%). It is concluded that patients with a less than 50%stenosis six months after PTCA show sustained improvement intheir functional status and myocardial perfusion, four to sixyears after the procedure suggesting continued patency of thecoronary artery. 相似文献
126.
目的:探讨巨大浆膜下子宫肌瘤(giant subserous hysteromyoma,GSH)的CT与MRI表现,以期提高诊断水平。方法:回顾性分析15例GSH的CT平扫、增强扫描及14例MRI平扫1、0例增强扫描表现并与手术病理结果对照。结果:5例CT表现呈非均匀实性的GSH在增强后内部呈多个大小不等的结节状改变,其间可见分隔结构,4例呈非均匀实性的GSH增强后呈"漩涡状"混杂密度,3例GSH瘤体边缘见低密度带。MRI T1WI所有肌瘤表现为等、低信号,T2WI表现为低或混杂信号,5例瘤体内部为结节状改变,其间可见高信号分隔结构,7例瘤体边缘见低信号带。结论:GSH的CT与MRI表现有一定的特征性,具有较高的诊断价值。 相似文献
127.
目的:探讨喉部CT仿真内窥镜(CT virtual endoscopy,CTVE)的成像质量及其影响因素。方法:对84例喉部螺旋CT扫描者行CTVE成像,根据喉腔内部结构、病灶、黏膜皱襞的显示情况和有无伪影将CTVE图像分为3级,分别比较CTVE技术在不同的扫描层厚、重建层厚及阈值的情况下图像质量的优劣。结果:CT原始扫描层厚为2mm、3mm分别与5mm、8mm的CTVE图像质量相比较,有显著性差异(P<0.05);重建层厚为2mm、3mm与5mm相比较,均有显著性差异(P<0.05);阈值为 -800— -600HU与阈值为-300HU相比较,有显著性差异(P<0.05)。结论:不同的CT原始扫描层厚、重建层厚及阈值对CTVE图像的质量影响有明显差异。选用合适的原始扫描参数及重建参数,可以提高CTVE图像的质量,对喉部疾病的诊断很有帮助。 相似文献
128.
目的 探讨X线、CT及血管造影对原发性十二指肠恶性肿瘤的诊断价值及鉴别诊断。资料与方法 回顾分析经手术和/或病理证实的46例原发性十二指肠恶性肿瘤的l临床及影像学资料,46例全部作过十二指肠气钡双对比造影,并有13例作低张十二指肠插管造影;28例作CT检查;11例作数字减影血管造影。结果 胃十二指肠双对比造影及低张十二指肠插管诊断十二指肠癌24例;平滑肌肉瘤6例;恶性淋巴瘤4例。诊断总符合率为73.91%(34/46)。误诊率为17.39%(8/46),漏诊率为8.7%(4/46)。CT检查28例,确诊十二指肠癌4例,平滑肌肉瘤7例。误诊为腹腔脓肿2例,平滑肌瘤6例,腹腔恶性肿瘤9例。诊断符合率为39.29%(11/28),误诊率为60.71%(17/28)。血管造影11例,9例检出病变,6例确诊为十二指肠恶性肿瘤,3例误为良性肿瘤,2例未发现明显肿瘤血管。确诊率为54.55%(6/11),误、漏诊率分别为27.27%(3/11)、18.18%(2/11)。结论 胃十二指肠气钡双对比造影是发现十二指肠恶性肿瘤最简单易行的方法,它和胃镜配合能得到病理学诊断。低张十二指肠插管造影对重度肠腔狭窄或阻塞患者显示病变范围起补充作用。CT能显示管外型恶性肿瘤的软组织块影及管壁破坏和有无淋巴结肿大。血管造影能根据血供来源明确钡餐难发现、CT仅显示与肠管无明显联系的平滑肌肉瘤,并可进行栓塞IE血治疗。 相似文献
129.
130.
阻塞性肺病呼气末肺残气量的CT评价 总被引:1,自引:0,他引:1
目的:探讨呼气末高分辨率CT(HRCT)对阻塞性肺病(OLD)患者的肺残气量的评估价值.方法:对有肺功能检测结果的13名健康志愿者与14例OLD患者行吸气与呼气末HRCT扫描,测量吸气与呼气状态下肺CT值,并目测呼气末HRCT扫描时肺残气量的范围.结果:所有的OLD与8名健康志愿者都有肺内空气残余,但OLD的范围明显增大.OLD患者在吸气与呼气时肺CT值变化及残气量分数与健康者明显不同,且与肺功能密切相关(P<0.01).结论:呼气末HRCT可用于评估OLD患者肺残气量并可诊断这类疾病.肺CT值的测量与肺残气量的评估是两种有价值的分析方法. 相似文献