非小细胞肺癌影像学分期研究进展

非小细胞肺癌是一种极为常见的癌症,早期非小细胞肺癌的影像学诊断尤为重要,对于该病诊断方法很多:普通CT、低剂量CT(LDCT)、核磁共振(MRI)、正电子发射计算机体层显像/x线计算机体层成像(PET/CT)、磁共振弥散加权成像(DWI),现就影像学技术在非小细胞肺癌分期中的应用现状及发展方向进行综述。     

无已知冠心病病人多层CT冠状动脉成像的费用和临床结果:与SPECT心肌灌注显像比较

目的相匹配的两组无已知冠心病(CAD)人群分别行多层CT冠状动脉成像及单光子发射计算机体层摄影(SPECT)心肌灌注显像,对其费用和临床结果进行对照研     

PET-CT在神经系统疾病诊断中的应用

正电子发射计算机断层(PET)脑功能的研究是探知脑功能重要手段之一,在此领域已经有了长足的进展,主要应用的方面是:脑代谢显像、脑灌注和脑血流显像、脑受体显像,其中以代谢显像应用最为广泛。特异性显像剂的开发是未来发展的方向,PET显像会在脑功能领域显示出独特的优势。多层螺旋计算机体层摄影(MSCT)的脑灌注成像为超早期诊断脑梗死和对脑肿瘤的诊断、评估及预后的监测起到了重要的作用。PET-CT联合起来必定会促进神经系统影像的发展。     

肿瘤乏氧组织显像剂的研究进展

乏氧组织显像剂能选择性地滞留在乏氧组织或细胞中,通过无创性的核医学正电子发射体层摄影术/单光子发射计算机体层摄影术可评价实体肿瘤缺氧状态.一些显像剂适宜进行乏氧显像并能很好地反映肿瘤乏氧及其程度等情况,这些信息在肿瘤的临床诊断决策中起到重要作用.     

99mTc-MIBI显像在131I治疗分化型甲状腺癌淋巴结转移灶中的临床价值

目的：探讨^99mTc-甲氧基异丁基异腈(methoxyisobutylisonitrile,MIBI)显像辅助诊断分化型甲状腺癌(differentiated thyroid carcinoma,DTC)淋巴结转移的价值。方法：纳入临床确诊DTC淋巴结转移患者78例。患者在接受放射性碘131(iodine 131,¹³¹I)治疗前均进行颈部超声、^99mTc-MIBI颈胸部显像(多时相)、计算机体层成像(computed tomography,CT)和/或¹⁸F-FDG正电子发射体层成像(positron emission tomography,PET)/CT。¹³¹I治疗后96 h进行¹³¹I全身扫描和¹³¹I单光子发射计算机体层成像(single-photon emission computed tomography,SPECT)/CT颈胸部显像。¹³¹I治疗前后动态检测血清甲状腺球蛋白(thyroglobul...     

核素骨显像在儿科中的应用

放射性核素骨显像是诊断骨和软组织感染的选择性检查方法,不但有助于隐匿性骨折(X射线诊断阴性)的诊断,在评定小儿可疑非意外损伤方面起重要的补充作用,还可为无法解释的小儿骨痛或跛行提供诸如外伤、肿瘤、或炎症性病变的诊断依据。小儿核素骨显像要求精确的操作才能获得较清晰的诊断图像,常规全身骨显像、缩放比例、附加视图及单光子发射型计算机体层摄影术的使用等都是小儿检查的常规内容,联合CT的融合图像更进一步提高诊断的灵敏度、可信度和精确度。新的放射性药物如Na18F可能在不断更新变化的儿科骨显像技术中起重要作用。     

高原地区冠心病患者核素心肌显像和冠状动脉造影的对比

目的：探讨核素心肌显像和冠状动脉造影在冠心病诊断中的临床意义,并与平原地区资料相比较,探讨高原地区缺氧环境中核素心肌显像在临床中的应用价值。方法：核素心肌显像：采用单光子发射计算机体层摄影（SPECT）,根据充盈缺损部位确定缺血或梗塞部位。冠状动脉造影：采用经右股动脉穿刺,冠状动脉管径狭窄≥50％时判断为冠状动脉造影结果阳性。结果：核素心肌显像对冠心病的诊断敏感性为95．2％,特异性为77.8％,阳性预测值为97．6％,阴性预测值为77．8％。结论：核素心肌显像对冠心病的诊断有较大价值。     

正电子发射断层显像／X线计算机体层成像在脊柱孤立性浆细胞瘤中的诊断价值

目的探讨脊柱孤立性浆细胞瘤（SBP）的18 F-脱氧葡萄糖（FDG）正电子发射断层显像／）（线计算机体层成像（PET／CT）诊断价值。方法收集3例经手术病理证实的SBP患者的PET／CT图像。结合文献对其临床、病理和影像学表现进行回顾性分析。结果3例肿瘤均发生于胸椎,分别发生于T4、T6和T11,3例病变均位于椎体,PET／CT表现为椎体膨胀性、穿凿样溶骨性骨质破坏及软组织肿块,边缘有硬化带,呈中一高度不均匀葡萄糖代谢增高。结论脊柱孤立性浆细胞瘤好发于中老年,以胸椎为好发部位,PET／CT全身扫描有助于鉴别诊断,提高诊断的准确性。     

提高肌肉骨骼肿瘤的影像学诊断水平

正确应用肌肉骨骼系统影像学检查是提高肌肉骨骼肿瘤诊断水平的关键之一。CT、MRI和正电子发射计算机体层摄影(positron emission tomographv，PET)等影像学方法不仅丰富了医学影像的成像手段和方法，而且从形态解剖结构观察发展为观察功能代谢的变化，提高了诊疗和鉴别诊断水平.放射     

采用各向同性的三维分辨率恢复有序子集最大期望值法迭代重建儿童骨99Tcm-MDP SPECT影像

目的对各向同性的三维分辨率恢复有序子集最大期望值法(OSEM-3D)迭代重建的儿童99Tcm标记的亚甲基二磷酸盐(MDP)单光子发射计算机体层摄影(SPECT)骨显像     

Morphological and functional MRI, MRS, perfusion and diffusion changes after radiosurgery of brain metastasis

Radiosurgery is a noninvasive procedure where spatially accurate and highly conformal doses of radiation are targeted at brain lesions with an ablative intent. Recently, radiosurgery has been established as an effective technique for local treatment of brain metastasis. After radiosurgery, magnetic resonance (MR) imaging plays an important role in the assessment of the therapeutic response and of any complications. The therapeutic approach depends on the imaging findings obtained after radiosurgery, which have a role in the decision making to perform additional invasive modalities (repeat resection, biopsy) to obtain a definite diagnosis and to improve the survival of patients. Conventional MR imaging findings are mainly based on morphological alterations of tumors. However, there are variable imaging findings of radiation-induced changes including radiation necrosis in the brain. Radiologists are sometimes confused by radiation-induced injuries, including radiation necrosis, that are seen on conventional MR imaging. The pattern of abnormal enhancement on follow-up conventional MR imaging closely mimics that of a recurrent brain metastasis. So, classifying newly developed abnormal enhancing lesions in follow-up of treated brain metastasis with correct diagnosis is one of the key goals in neuro-oncologic imaging. To overcome limitations of the use of morphology-based conventional MR imaging, several physiological-based functional MR imaging methods have been used, namely diffusion-weighted imaging, perfusion MR imaging, and proton MR spectroscopy, for the detection of hemodynamic, metabolic, and cellular alterations. These imaging modalities provide additional information to allow clinicians to make proper decisions regarding patient treatment.     

脑放射损伤的影像学研究进展

脑放射损伤发病机制主要有三种学说即血管损伤、胶质损伤和免疫反应机制,最近多数学者的研究支持血管和胶质损伤机制,血管方面的改变在晚期放射效应中起主要作用。CT和MRI对局限性脑损伤和弥漫性脑白质损伤可明确诊断。MRI的T2加权成像(T2WI)显示水分变化敏感性高,又不受颅底线束硬化伪影的影响,MRI发现白质病变的敏感性是CT的2~3倍。如果是脑本身肿瘤放疗后,CT和MRI区别病灶复发或放射性坏死比较困难,PET和MRS(磁共振波谱成像)在两者鉴别诊断中则初步呈现出一定的优势。行PET检查时,如为肿瘤则代谢活跃,坏死则代谢低下,但敏感性和特异性欠理想。MRS测量感兴趣区内代谢产物的量或比率有助于两者的鉴别诊断。另外,PET功能成像和MRS还可预测放疗病人较早期无症状的可逆性放射损伤,以便及时应用激素等药物治疗,避免其进一步发展为临床症状明显的不可逆性损伤。     

MR spectroscopy in post-treatment follow up of brain tumors

PurposeTo detect the role of MR spectroscopy in evaluating the whole area of signal alteration within the irradiated volume aiming to differentiate recurrent/residual tumors from radiation injury and to detect the tumor margin and extent.Materials and methodsThis prospective study included 25 patients with previously treated primary intracranial tumors. All patients received radiotherapy. MRI and multivoxel MRS were performed. The volume of interest was placed over the whole area of signal alteration. The spectra were analyzed for the signal intensity of choline (Cho), creatine (Cr), and N-acetyl aspartate (NAA), lipid (Lip), lactate (Lac), and myo-inositol (mI). Metabolite ratios for Cho/NAA, Cho/Cr, and NAA/Cr were calculated.ResultsCho/NAA and Cho/Cr were significantly higher while NAA/Cr ratios were significantly lower in tumors than radiation injury (p = 0.001 for all ratios). The Cho/NAA and Cho/Cr ratios were significantly higher in radiation injury than in normal-appearing brain tissue (p = 0.032 and p = 0.008, respectively), whereas NAA/Cr was insignificantly lower in radiation injury than normal-appearing brain tissue (p = 0.051). Value >1.8 for Cho/NAA ratio was considered as indicator for tumor.ConclusionMR spectroscopy can differentiate recurrent/residual tumor from radiation injury and delineate the tumor margin and extent.     

18F-氟脱氧葡萄糖PET在放射性脑损伤诊断中的应用

随着放疗在脑部肿瘤治疗中的广泛应用,放射性脑损伤的诊断和治疗就显得尤为重要.18F-氟脱氧葡萄糖PET通过对脑组织细胞代谢功能的检测,能够早于形态学检查发现放射性脑损伤,并且在很大程度上能够鉴别放射性脑坏死与肿瘤复发,以指导临床治疗.     

扩散加权成像在胎儿脑发育中的应用进展

胎儿先天性发育异常是围生儿死亡和致残的重要原因,产前早期准确诊断是干预及治疗的关键。胎儿MR成像能够弥补超声检查的不足,是胎儿产前诊断的一种重要辅助手段。扩散加权成像不但能够评估胎儿的正常脑发育过程,而且对脑先天发育异常及胎儿宫内脑损伤的早期评估具有重要意义。现就扩散加权成像在胎儿脑发育中的应用进展予以综述。     

Intra-axial brain tumours

The radiological diagnosis and differential diagnosis of intra-axial tumours no longer relies on CT scan and routine MR sequences alone. Standard multiplanar imaging has to be combined with fMRI to allow the exact anatomic location of the lesion and precise determination of the extension of the tumour. Perfusion and diffusion MR is becoming more and more important in the differential diagnosis of cerebral mass lesions and in the grading and typing of gliomas. More sophisticated techniques such as diffusion tensor imaging and spectroscopy will further enhance the value of the radiological studies.     

脑肿瘤治疗后磁共振质子波谱评价

目的：评估脑肿瘤手术后、放疗后的多体素^1H MRS的临床应用价值。方法：21例脑肿瘤手术后、放疗后行多体素^1H MRS检查。结果：^1H MRS显示脑肿瘤内Cho升高5例，其中4例手术证实为肿瘤复发，1例为胶质增生。放射治疗后肿瘤生长抑制。^1H MRS表现为Cho降低，NAA、Cr明显下降。放射性坏死^1H MRS表现为肿瘤坏死区出现乳酸-脂质峰。结论：^1H MRS可评估脑肿瘤术后复发和监测肿瘤放疗后的病理变化，是一种有价值的检查方法。     

Contribution of MRI and MR angiography in early diagnosis of brain death

The objective of this study was to investigate whether the findings of MR imaging and MR angiography could accurately and early diagnose brain death in comatose patients. Thirty comatose patients were studied with MRI and MR arteriography. In 20 patients (group A) presenting with a Glasgow coma scale (GCS) 3–6, the final clinical diagnosis was brain death. In ten comatose patients with a GCS 4–6 and no clinical signs of brain death (group B), the clinical follow-up did not reveal brain death in a period of 12 months. The MRI examination consisted of turbo fluid-attenuated inversion recovery and T2 turbo spin-echo pulse sequences. The MR arteriography was performed with a 3D inflow pulse sequence. In 12 patients with brain death and 5 patients with no signs of brain death, a 3D phase contrast MR venography was also applied. Magnetic resonance imaging in all patients showed variable edema with swelling of the cerebral gyri, small ventricular system, and basilar subarachnoid spaces. In group A, MRI in addition showed tonsillar herniation. In group A, MR arteriography revealed no arterial flow in the intracranial circulation, whereas MR venography showed in 9 patients no opacification of the sagittal and straight sinuses or visualization of intracranial veins. In contrast, MR angiography showed intact intracranial vessels in patients of group B. In conclusion, MR imaging and MR angiography may be reliable ancillary tests for use in early diagnosis of brain death and further work is required to validate its utility. Electronic Publication     

Comparison of the effectiveness of MRI perfusion and fluorine-18 FDG PET-CT for differentiating radiation injury from viable brain tumor: a preliminary retrospective analysis with pathologic correlation in all patients

ObjectivesDifferentiating radiation injury from viable tumor is important for optimizing patient care. Our aim was to directly compare the effectiveness of fluorine-18 fluorodeoxyglucose (FDG) positron emission tomography–computed tomography (PET-CT) and dynamic susceptibility-weighted contrast-enhanced (DSC) magnetic resonance (MR) perfusion in differentiating radiation effects from tumor growth in patients with increased enhancement following radiotherapy for primary or secondary brain tumors.Materials and methodsWe retrospectively identified 12 consecutive patients with primary and secondary brain tumors over a 1-year period that demonstrated indeterminate enhancing lesions after radiotherapy and that had undergone DSC MR perfusion, FDG PET-CT, and subsequent histopathologic diagnosis. The maximum standardized uptake value (SUV) of the lesion (SUV_{lesion max}), SUV_ratio (SUV_{lesion max}/SUV_{normal brain}), maximum relative cerebral blood volume, percentage of signal intensity recovery, and relative peak height were calculated from the positron emission tomography and MR perfusion studies. A prediction of tumor or radiation injury was made based on these variables while being blinded to the results of the surgical pathology.ResultsSUV_ratio had the highest predictive value (area under the curve=0.943) for tumor progression, although this was not statistically better than any MR perfusion metric (area under the curve=0.757–0.829).ConclusionsThis preliminary study suggests that FDG PET-CT and DSC MR perfusion may demonstrate similar effectiveness for distinguishing tumor growth from radiation injury. Assessment of the SUV_ratio may increase the sensitivity and specificity of FDG PET-CT for differentiating tumor and radiation injury. Further analysis is needed to help define which modality has greater predictive capabilities.     

Gadofluorine M增强磁共振成像在大鼠放射性脑损伤早期诊断中的实验研究

目的 探讨新型对比剂Gadofluorine M(Gf)在MRI早期诊断大鼠放射性脑损伤中的应用。方法 66只大鼠随机分为25、35、45、55和65 Gy组,各12只,对照组6只,X射线照射构建大鼠放射性脑损伤模型,照射后1~8周行MRI平扫及Gf增强扫描,每周1次。另取12只大鼠分为55及65 Gy组,每组6只,照后3~8周行钆喷酸葡胺(Gd-DTPA)增强及Gf增强扫描,每周1次。比较损伤显像时间、MRI参数和病理学改变评价放射损伤。结果 25及35 Gy放射组在观察2个月内MRI未发现异常信号改变,45、55及65 Gy组在放射后4~6周内,T1WI Gf增强扫描中逐渐出现强化改变,信号强度与对照组、25和35 Gy组差异有统计学意义(F =2.15, P ＜0.05),出现时间与剂量成反比(r=－0.62, P ＜0.05)。Gd-DTPA增强及Gf增强扫描对比结果显示,Gd-DTPA增强扫描未发现明显改变时Gf增强可见损伤改变,Gf增强信号强度较平扫及Gd-DTPA增强明显强化(F =2.74, P ＜0.01)。病理检查示65 Gy组病理学检查发现部分区域出现毛玻璃样变性,其余各组均未发现明显异常。结论 Gadofluorine M增强改变出现在病理改变之前,可用以早期发现放射性脑损伤,较常规扫描序列及Gd-DTPA增强扫描具有明显优势。