用ROC曲线法分析99Tcm-HL91肺肿瘤阳性显像的诊断效能

目的探讨半定量分析及接受器工作特性(ROC)曲线法在99Tcm-4,9-二氮-3,3,10,10-四甲基十二烷-2,11-二酮肟(HL91)肿瘤阳性显像鉴别肺部良恶性肿块中的价值.方法经CT检查发现肺部肿块的患者50例,均经活组织检查或手术病理检查证实.根据病理检查结果分为恶性组37例和良性组13例.术前行99Tcm-HL91 2 h、4 h平面显像及4 h断层显像,分别使用视觉判断法、半定量分析及ROC曲线法分析显像结果.结果①视觉判断法99Tcm-HL91显像的灵敏度、特异性和准确性分别为97.3%、69.2%和90.0%.②肿瘤/正常肺组织(T/N)比值半定量分析及ROC曲线法恶性组2 h、4 h平面显像及4 h断层显像T/N比值分别为1.52±0.19、1.73±0.28及2.84±0.97;良性组分别为1.20±0.16、1.24±0.20及1.52±0.40.各个时相的曲线下面积分别为0.909±0.056、0.945±0.039、0.953±0.034.从99Tcm-HL91断层显像ROC曲线的界值点找到1个界点(T/N=1.76),以其作为判断良、恶性的诊断阈值,灵敏度、特异性和准确性分别为100%、84.6%和96.0%.③视觉判断法与半定量分析法比较T/N比值半定量分析及ROC曲线法使诊断的灵敏度、特异性和准确性都有提高,尤其特异性.但两种方法间差异无显著性(P均＞0.05).结论半定量分析及ROC曲线法的诊断阈值可进一步提高99Tcm-HL91肺部肿瘤阳性显像的诊断效能.     

用99Tcm-HL91显像预测脑肿瘤放疗敏感性

目的应用99Tcm-4,9-二氮-3,3,10,10-四甲基十二烷-2,11-二酮肟(HL91)乏氧显像预测脑肿瘤放疗疗效.方法经临床确诊的30例未治疗的脑肿瘤患者,肘静脉注射99Tcm-HL91 740 MBq后进行早期(10 min)、中期(2 h)和晚期(4 h)显像.应用感兴趣区(ROI)技术勾画并分别测定早、中、晚期肿瘤部位放射性计数(T),以及对侧相应部位放射性计数(N),求出相应T/N比值.检查后患者接受放射治疗,4周后按WHO标准,在放疗科医师协助下进行放疗疗效评价,分为完全缓解(CR),部分缓解(PR),无变化(NC)和进展加重(PD),并与99Tcm-HL91显像结果比较.结果①30例脑肿瘤患者99Tcm-HL91显像早、中、晚各时相的T/N比值分别为1.453±0.292,1.532±0.299和1.607±0.305,各时相间差异均有显著性(P=0.000,双侧).②30例脑肿瘤患者中CR 0例,PR 15例,NC 6例,PD 1例,死亡或失访共8例;放疗有效组(CR+PR)与放疗无效组(NC+PD)99Tcm-HL91显像早、中和晚期相T/N比值分别为1.333±0.277与1.779±0.183,1.409 ±0.274与1.856±0.185和1.484±0.278与1.937±0.191,差异均有显著性(P=0.001,双侧).③受检者均未发现主观性不适和毒副作用.④99Tcm-HL91在鼻、口咽部有明显放射性摄取.结论99Tcm-HL91脑肿瘤显像可预测脑肿瘤的放疗敏感性,对鼻、口咽部肿瘤应用价值较低.     

小鼠恶性淋巴瘤99Tcm-HL91显像实验研究

目的验证乏氧显像剂99Tcm-4,9-二氮-3,3,10,10-四甲基十二烷-2,11-二酮肟(HL91)对IRM-2小鼠IRM-2-ML恶性淋巴瘤的探测作用.方法测定不同时间99Tcm-HL91在正常及荷瘤小鼠体内的分布,并进行平面显像.结果 99Tcm-HL91能选择性地浓集于肿瘤组织,且清除较慢.肿瘤/血液比值和肿瘤/肌肉比值均随时间延长而增加,2 h时分别为2.63±0.25和3.37±0.22,6 h时分别为3.51±0.17和6.44±0.29.平面显像中,肿瘤灶清晰可见.结论肯定了IRM-2-ML恶性淋巴瘤为实体肿瘤的结论,确证了99Tcm-HL91探测乏氧组织的作用.     

99Tcm-HL91乏氧显像在鼻咽癌治疗中的应用

目的探讨99Tcm-4,9-二氮-3,3,10,10-四甲基十二烷-2,11-二酮肟(HL91)SPECT/CT乏氧断层显像在鼻咽癌(NPC)治疗中的临床应用价值.方法38例NPC患者按常规进行鼻咽、颈部99Tcm-HL91断层显像;并对病灶的靶/非靶组织放射性比值(T/N)进行半定量分析;其中16例NPC患者在放疗前、后均行99Tcm-HL91乏氧显像;同时对16例患者按乏氧靶区调整放疗剂量,行后程三维适形放疗(3DCRT).结果NPC患者乏氧断层显像检查阳性率约为82%;99Tcm-HL91乏氧显像对NPC诊断的灵敏度、特异性、准确性分别为82%、78%、87%;放疗前鼻咽、颈部乏氧病灶的T/N分别为2.37±1.13、2.17±1.08,两者比较差异无显著性(P＞0.05).16例NPC患者在放疗前、后NPC病灶的T/N平均值分别为2.21±1.05、1.29±0.39,两者比较差异有显著性(P＜0.001);NPC病灶的乏氧状态与其对放疗的响应密切相关,相关系数r为0.532,P＜0.01.NPC 3DCRT的近期疗效优于常规放疗,肿瘤局部控制率较高,急性放射毒性较轻.结论99Tcm-HL91乏氧显像可监测NPC病灶的乏氧状态,指导NPC的3DCRT;NPC乏氧靶区3DCRT可提高其放疗疗效,减轻急性放射毒性.     

99Tcm-HL91显像用于骨转移瘤的诊断

目的 探讨乏氧显像剂99Tcm-4,9-二氮-3,3,10,10-四甲基十二烷-2,11-二酮肟(HL91)在骨转移瘤诊断中的应用价值.方法 27例骨痛患者,其中19例经病理检查证实为骨转移瘤(未行放化治疗),8例为骨良性病变.所有患者均行99Tcm-亚甲基二膦酸盐(MDP)显像,2 d后注射99Tcm-HL91740 MBq,注射4 h后依据99Tcm-MDP显示的病灶进行断层显像,利用感兴趣区(ROI)技术,计算肿瘤与对侧正常组织的放射性(T/N)比值.采用SPSS 11.0软件进行t检验.结果 19例骨转移患者99Tcm-MDP显像提示的85处病灶,有79处99Tcm-HL91显像呈异常放射性浓聚;经病理检查或临床证实的8例骨良性疾病中,99Tcm-MDP显像提示的12处病灶99Tcm-HL91显像全部呈阴性.HL91断层显像骨转移组和骨良性疾病组的T/N比值分别为1.877±0.288和0.735±0.236,差异有统计学意义(t=13.065,P＜0.05).肺癌、前列腺癌骨转移病灶的T/N比值分别为1.915±0.344和1.825±0.175,2种病理类型间差异无统计学意义(t=1.378,P＞0.05).结论 99Tcm-HL91显像在骨骼良恶性病变的鉴别中可能有一定价值.     

非小细胞肺癌放疗中99Tcm-HL91 SPECT乏氧显像研究

目的通过99Tcm-4,9-二氮-3,3,10,10-四甲基十二烷-2,11-二酮肟(HL91)系列乏氧显像研究非小细胞肺癌放疗前、中和后乏氧的变化.方法拟接受三维适形放疗的非小细胞肺癌患者20例,放疗前1～2 d、放疗过程中(接受30～40 Gy照射)和放疗后1～2 d分别行99Tcm-HL91 SPECT显像.利用感兴趣区(ROI)技术计算肿瘤/对侧相应部位放射性计数比值(T/N),分析放疗不同时期肿瘤乏氧的变化.结果放疗前、中和后显像的T/N(4 h)分别为1.56±0.19,1.40±0.12和1.29±0.13,差异有显著性(P=0.01).结论该实验为研究人体肿瘤再氧合提供了有价值的信息.     

肺肿瘤99Tcm-N(NOEt)2SPECT显像与P-糖蛋白和增殖细胞核抗原表达的关系

目的探讨肺肿瘤99Tcm-氮-二(N-乙基-N-乙氧基二硫代氨基甲酸盐)[N(NOEt)2]SPECT显像病变部位与对侧对应正常肺组织放射性比值(T/N)与术后病理组织中P-糖蛋白(P-gp)和肿瘤增殖细胞核抗原(PCNA)表达间的关系.方法对22例(20例为术前未经药物治疗的肺癌,2例为肺良性病变)患者进行手术,取肿瘤标本,经常规石蜡切片,用免疫组织化学技术检测病变组织P-gp和PCNA表达,并与术前99Tcm-N(NOEt)2 SPECT显像T/N比值对比.结果22例患者中,20例肺恶性肿瘤99Tcm-N(NOEt)2 SPECT显像均表现为异常放射性浓聚,T/N比值为1.29±0.04;2例肺良性病变99Tcm-N(NOEt)2显像T/N比值为1.08±0.13,其中1例为假阳性.22例患者除1例肺腺癌仅P-gp表达阴性外,其余患者P-gp、PCNA均呈阳性表达.22例患者99Tcm-N(NOEt)2SPECT延迟显像T/N比值与术后病理组织中P-gp和PCNA表达程度均无关(r值分别为0.123和-0.145,P均＞0.05,双侧),且病理组织中P-gp与PCNA表达程度也无关(r=0.062,P＞0.05,双侧).结论肿瘤细胞摄取99Tcm-N(NOEt)2与其P-gp和PCNA表达程度无关.     

99Tcm-HL91乏氧显像在甲状腺结节良恶性鉴别诊断中的应用

目的 评价99Tcm4,9-二氮-3,3,10,10-四甲基十二烷-2,11-二酮肟(HL91)对甲状腺结节良恶性鉴别诊断的临床价值.方法 对58例经触诊或超声检查存在甲状腺结节的患者进行99Tcm-HL91甲状腺早期(10 min)及延迟(4 h)平面显像,应用感兴趣区(ROI)技术计算靶/非靶(T/N)比值并进行比较.组间比较采用成组设计两样本均数t检验,率的比较用χ2检验.结果 患者均经手术或细针穿刺病理检查,其中21例为甲状腺癌,37例为甲状腺良性结节.99Tcm-HL91显像诊断甲状腺癌的灵敏度、特异性和准确性分别为85.7%,94.6%和91.4%,不同甲状腺癌病理类型的显像灵敏度差异无统计学意义(χ2=0.778,P＞0.05),但结节越大灵敏度越高.甲状腺癌与甲状腺良性结节组早期及延迟相T/N比值分别为1.07±0.04,1.25±0.03和0.92±0.10,0.91±0.12,组间在10 min时T/N比值差异无统计学意义(t=1.900,P＞0.05),4 h时T/N比值差异有统计学意义(t=3.885,P＜0.001).结论 用99Tcm-HL91乏氧显像判断甲状腺结节的良恶性有一定的临床价值,显像时间以4 h为佳.     

非小细胞肺癌99Tcm-HL91显像与恶性程度、HIF-1α表达的相关性

目的 探讨非小细胞肺癌^99Tc^m-4,9-二氮-3,3,10,10-四甲基十二烷-2,11-二酮肟（HL91）显像与其恶性程度、乏氧诱导因子-1α（HIF-1α）表达的关系.方法 35例非小细胞肺癌患者,注射^99Tc^m-HL91后4 h进行胸部前后位、后前位平面及断层显像,利用感兴趣区（ROI）技术,计算肿瘤与对侧正常组织（T/N）的放射性比值.所有患者均行组织病理学检查,标本行HE染色、免疫组织化学染色.结果 ^99Tc^m-HL91平面显像：35例非小细胞肺癌患者中30例显像阳性;断层显像：33例显像阳性.定量分析：4 h断层像T/N比值明显高于平面像（t=10.619,P=0.000）;HL91显像的T/N比值与肺癌细胞恶性程度相关（r=0.626,P=0.000）,鳞癌、腺癌之间的T/N比值差异无显著性（t=0.981,P=0.330）.HIF-1α主要表达于肺癌细胞胞核及胞质,肿瘤间质细胞也可见少量表达,肿瘤坏死区周围及肿瘤浸润边缘部的癌细胞HIF-1α表达明显增多.鳞癌、腺癌间的HIF-1α表达差异无显著性（ZC=1.295,P=0.730）,HIF-1α表达强弱与肺癌细胞恶性程度相关（rs=0.467,P=0.005）,与肿瘤大小无关.非小细胞肺癌各组织学分级HL91显像T/N比值与HIF-1α表达强弱均高度相关（r=0.756～0.893,P＜0.05）.结论 HL91显像的T/N比值与肺癌细胞恶性程度呈中度相关,与恶性肿瘤细胞HIF-1α表达呈高度相关.HL91显像可以用来预测肿瘤恶性程度及放、化疗疗效.     

99Tcm-HL91肺癌显像的临床应用

目的 探讨~(99)Tc~m-4,9-二氮-3,3,10,10-四甲基十二烷-2,11-二酮后(HL91)显像对肺部肿瘤定性的价值。方法 对32例肺部肿瘤患者注射~(99)Tc~m-HL91后10 min,2、4 h进行显像,将显像结果分为~(99)Tc~m-HL91显像阳性组和阴性组,对~(99)Tc~m--HL91显像阳性患者利用感兴趣区(ROI)技术分别勾画各时相肿瘤(T)与对侧相应部位(N)ROI,计算T/N比值。所有患者均经手术病理检查证实,将显像结果与CT和病理检查结果对照。结果 ~(99)Tc~m-HL91显像灵敏度为82.6％,特异性为100％,准确性为87.5％。CF灵敏度为69.6％,特异性为100％,准确性为78.1％。CT提示肺癌16例中,~(99)Tc~m-HL91显像均阳性。随~(99)Tc~m-HL91显像时间延长,T/N比值增高,10 min为1.620±0.320,2 h为1.737±0.416,4 h为1.909±0.491。10 min与2 h差异无显著性(P>0.05),10 min与4 h差异有显著性(P<0.05)。肺腺癌组与肺鳞癌组各时相T/N比值差异无显著性(P>0.05)。结论 ~(99)Tc~m-HL91显像判断肺肿瘤良恶性有较好价值。     

Stress MR imaging for evaluation of popliteal artery entrapment

The popliteal artery entrapment (PAE) syndrome has been recognized as a cause of arterial occlusion in young people. It is the result of an anomaly of the relationship between the popliteal artery and the gastrocnemius muscle. Eight young healthy volunteers (16 legs) and six patients (10 legs) with suspected PAE underwent magnetic resonance (MR) imaging. Gradient-echo images were obtained in axial planes with the leg at rest and during active plantar flexion against resistance. Imaging at rest allowed identification of PAE signs in only one leg, which had an anomalous medial course of the popliteal artery. In the other cases, only the stress technique was able to show signal loss in the popliteal artery due to muscular compression (two legs) or the presence of accessory muscle slip around the vessel (two legs), as confirmed at surgery. MR imaging is therefore a useful technique for the diagnosis of PAE because of its capability of combining information obtainable with other modalities.     

MR imaging of muscle and tender points in fibromyalgia

Fibromyalgia is a syndrome manifested by chronic, diffuse muscu-loskeletal aching and soreness, palpable muscle tender points, and other symptoms. Standardized clinical diagnostic criteria have recently been developed. Skeletal muscle has been postulated as the end organ in this disease. Biochemical, histologic, electromyographic, and conventional radiographic studies have demonstrated no definitive abnormality. This study sought to establish whether magnetic resonance (MR) imaging could demonstrate any abnormality in these patients. Eighteen patients were entered in the study, 14 of whom were able to complete their examinations. T1 -weighted, T2-weighted, gradient-echo, and STIR (short-tau inversion-recovery) sequences were performed in all patients, with selected patients examined with T1weighted, gadopentetate dimeglu-mine-enhanced sequences. The trapezius and suboccipital regions were imaged in patients who, clinically, had active fibro-myalgia. No abnormalities could be detected. The authors conclude that the conventional MR imaging used in this study was unable to depict any primary skeletal muscle abnormality in fibromyalgia.     

MR angiography of congenital heart disease: Value of segmented two-dimensional inflow technique and maximum-intensity-projection display

Magnetic resonance (MR) angiography of the cardiovascular system was evaluated in 41 patients with congenital heart disease by using a two-dimensional (2D) inflow technique based on a magnetization-prepared gradient-echo pulse sequence with segmented k-space data acquisition and electrocardiographic gating at 0.5 T. Inversion and saturation prepulses were used to suppress stationary tissue and enhance intravascular signal. Presaturation slabs were applied where certain vascular structures had to be suppressed. Sequence parameters were optimized by evaluating signal intensity and contrast characteristics for various flip angles and inversion and saturation delay times. The heart and intrathoracic vasculature were encompassed with 40–50 overlapping sections. Both 2D angiograms and maximum-intensity-projection images were evaluated. Combining data sets acquired in the sagittal and transverse orientations provided the most satisfactory information about the pulmonary arteries. The highest signal-to-noise ratios were obtained with a flip angle of 65° and short prepulse delay times. Two-dimensional MR angiography can provide useful diagnostic information but requires a thorough understanding of in-plane and hemodynamically induced signal intensity changes.     

MR imaging of disorders of the brachial plexus

The authors evaluated 64 consecutive patients with suspected brachial plexus (BP) abnormalities of diverse cause with magnetic resonance (MR) imaging, using the body coil and a standardized protocol. Of the 43 patients for whom follow-up was available, 25 were suspected of having neoplastic involvement of the BP, nine had sustained injuries, and nine presented with BP symptoms of uncertain cause. MR imaging was 63% sensitive, 100% specific, and 77% accurate in demonstrating the abnormality in this diverse patient population. When patients with neoplastic and traumatic disorders were considered separately, sensitivity increased to 81%, accuracy to 88%, and specificity remained unchanged. In the patients with a clinical diagnosis of idiopathic or viral plexitis, the MR imaging findings were normal, serving to exclude other structural abnormalities. It is concluded that MR imaging is valuable in the assessment of a wide range of BP disorders.     

MR imaging characteristics of noncancerous lesions of the prostate.

Radical prostatectomy specimens from 53 men with clinical stage A or B prostate cancer were retrospectively reviewed and compared with correlative axial T2-weighted magnetic resonance (MR) images obtained just before surgery. Non-cancerous lesions were evaluated for signal intensity and location. Focal high-signal-intensity areas (n = 72) were present in 81% of patients. The 26% of lesions seen in the central gland all correlated with cystic atrophy. Of the 53 lesions seen in the peripheral prostate, 47 (89%) were cystic atrophy without associated cancer, four (7.5%) cystic atrophy with cancer, and two (3.8%) focal inflammation. Focal low-signal-intensity areas (n = 42) were present in 60% of patients. Of the 31% of lesions in the central prostate, one-fifth correlated with benign prostatic hyperplasia (BPH) and four-fifths with fibrous tissue. Of the 69% of peripheral lesions, 83% corresponded to fibrous tissue, 10% to BPH, and 7% to normal tissue. Mixed lesions (n = 42) were present in 64% of patients; 86% of these were located centrally and 14% peripherally. All mixed central lesions were BPH; the peripheral lesions were areas of combined cystic atrophy and fibrosis. BPH of low or mixed signal intensity can extend into the peripheral prostate and mimic cancer. High-intensity cystic atrophy associated with cancer can mimic normal tissue.     

肾细胞癌的MRI研究进展

肾细胞癌是最常见的成人肾脏恶性肿瘤。近年来，多种功能MRI成像技术（如扩散加权成像、灌注加权成像等）、多参数MRI联合分析以及影像组学等新兴影像处理技术被证实在肾细胞癌的诊断中具有较大的价值。目前，研究热点多集中于良恶性肿瘤的鉴别、组织学亚型的区分、肿瘤分期、预测核分级及判断预后。就MRI新技术及图像处理技术在肾细胞癌中的研究进展予以综述。     

Dynamic contrast-enhanced MR imaging assessment of vascularized free fibular grafts

Magnetic resonance (MR) imaging may be a noninvasive method for assessing perfusion of vascularized bone grafts placed for treatment of avascular necrosis. One proximal femur of seven beagles was devascularized, with insertion of a vascularized fibular graft. MR imaging at 1 week (seven dogs) and 6 weeks (five dogs) after surgery included pre- and postcontrast spin-echo sequences, unenhanced twodimensional time-of-flight (TOF) vascular imaging, and dynamic gradient-echo imaging during infusion of gadolinium. Relative signal intensity values of selected regions obtained from the dynamic gradientecho images were plotted as percent enhancement versus time. In the operated hip, MR imaging did not show enhancement in six of seven femoral heads and greater trochanters at 1 week after surgery, with similar results after 6 weeks. MR imaging of fibular grafts 6 weeks after surgery showed an initial rapid increase in enhancement and a subsequent slower increase in five of five dogs, although no enhancement was seen in six of seven dogs at 1 week. These findings contrasted with a rapid initial increase in enhancement followed by slow decline in non-operated hips. Two-dimensional TOP imaging did not show the vascular pedicle of the graft in any dog. Findings of radionuclide bone scanning performed 1 week after surgery were consistent with devascularization of the operated femur and fibular graft. However, tetracycline distribution and histologic findings confirmed the viability of five of five grafts within the devascularized femurs 6 weeks after surgery. Thus, dynamic contrast-enhanced MR imaging at 6 weeks after surgery is valuable for assessing vascular bone graft perfusion, while similar imaging at 1 week may suggest otherwise.     

Influence of in vivo copper on MR images of the liver in rats

To investigate the effects of in vivo copper on magnetic resonance (MR) images, the authors studied Long-Evans cinnamon rats, which develop hepatitis and hepatocellular carcinoma as a result of abnormal copper metabolism. The livers of the rats were imaged before hepatitis developed; the absence of hepatic disease was confirmed histopathologically. The copper that accumulated in the liver of the rats was thought to exist in the form of divalent ions, which were suspected of reducing the T1 and T2 of neighboring protons. However, the signal intensities of the liver on T1- and T2*-weighted images did not change, suggesting that in vivo copper, even when accumulated abnormally, does not influence the signal intensity of MR images.     

Techniques for high-resolution MR imaging of atherosclerotic plaque

Atherosclerotic cardiovascular disease is the most common cause of death in the United States. Investigation of atherosclerotic plaque morphology and composition is important because the findings may be useful in predicting prognosis or response to therapy. This study presents high-resolution magnetic resonance (MR) imaging techniques developed on a 1.5-T whole-body imager with a custom-built surface coil, for characterizing the composition and morphology of plaque removed at carotid endarterectomy. The initial comparison of MR imaging and histologic results showed good correlation. In conjunction with MR angiography, these techniques could be used in in vivo imaging to define the size, location, and contents of atherosclerotic plaque at the carotid bifurcation.     

Dynamic MRI of the gallbladder lesions: Differentiation of benign from malignant

Forty-nine pathologically proven gallbladder lesions were evaluated in 45 patients using dynamic MRI with a spoiled gradient pulse sequence (SPGR), to access the ability of this technique to differentiate benign from malignant gallbladder lesions. The studies were reviewed retrospectively. Signal intensity of the lesions were measured. Twenty-one malignant and 28 benign lesions were classified into three categories: polypoid, diffuse wall thickening, and exophytic. Early and delayed enhancement patterns were evaluated. For the polypoid masses, malignant lesions (n = 9) demonstrated early and prolonged enhancements, whereas benign lesions (n = 14) had early enhancement with subsequent washout (P < .05). For diffuse gallbladder wall thickening, malignant lesions (n = 6) demonstrated early and prolonged enhancement and benign lesions (n = 14) showed relatively slow, prolonged enhancement (P < .05). The exophytic masses (n = 6) all were malignant and demonstrated early and prolonged enhancement. Dynamic MRI can help differentiate benign from malignant gallbladder lesions.