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1.
OBJECTIVES: It is important to recognize osteonecrosis of the jaws in patients treated with bisphosphonates because an early diagnosis can make a significant difference to the outcome of the disease. The aim of this study is to describe the radiological features of bisphosphonate osteonecrosis (BON) in order to aid its prompt recognition. METHODS: A conventional radiograph, a computed tomograph (CT), a magnetic resonance image (MRI) and a 99Tc(m)-MDP 3-phase bone scan were carried out for 11 patients with BON. The main imaging findings of osteonecrosis are described. RESULTS: Conventional radiography and CT displayed osteolytic lesions with the involvement of cortical bone. MRI demonstrated the characteristic features of osteonecrosis and the oedema of soft tissues. Both CT and MRI were very useful in defining the extent of the lesions. 99Tc(m)-MDP three-phase bone scan was the most sensitive tool to detect the osteonecrosis at an early stage. CONCLUSIONS: 99Tc(m)-MDP three-phase bone scans who could be used as a screening test to detect subclinical osteonecrosis in patients who have received bisphosphonates. CT scans and MRI are useful in defining the features and extent of osteolytic lesions.  相似文献   

2.
Thirty-seven patients with carcinoma of the cervix were prospectively staged by examination under anaesthesia (EUA), transvaginal and transrectal ultrasound, computed tomography (CT) and magnetic resonance imaging (MRI). Pathological correlation was available for 20 patients. In the pathologically staged patients, EUA agreed with the staging in 17, understaging three patients. Endosonography agreed with the staging in 19, CT in 16 and MRI in 18 patients. For the remaining 17 patients, endosonography agreed with the EUA findings in 13, CT in 12 and MRI in 12. This study has shown that endosonography and MRI are more accurate than CT in the local staging of carcinoma of the cervix. Computed tomography was least accurate in staging early tumours and differentiating between Stage Ib and IIb disease. Lymph node involvement was detected with equal frequency by both CT and MRI. Magnetic resonance imaging was useful in identifying vaginal and bladder wall involvement and in one patient showed features due to an unsuspected early pregnancy.  相似文献   

3.
Fibrosarcoma is a rare tumor involving the musculoskeletal system. Anatomic imaging modalities like CT and MRI are useful in characterization and staging of the tumor. FDG PET has variable sensitivity in evaluation of these tumors. Alternative tracers like FLT have been tried. It is a well-known fact that sarcomas are highly vascular. We report the utility of dynamic perfusion PET imaging using N13-ammonia in diagnosing a case of asymptomatic recurrence of fibrosarcoma in a 45-year-old patient. Despite very faint FDG avidity, ammonia perfusion imaging showed hypervascularity and allowed identification of the asymptomatic early recurrence.  相似文献   

4.
AIM: Although magnetic resonance (MR) imaging is widely used for rectal cancer staging, many centres in the UK perform computed tomography (CT) for staging rectal cancer at present. Furthermore in a small proportion of cases contraindications to MR imaging may lead to staging using CT. The purpose of this study was to evaluate the accuracy of current generation multidetector row CT (MDCT) in local staging of rectal cancer. In particular the accuracy of multiplanar (MPR) versus axial images in the staging of rectal cancer was assessed. MATERIAL AND METHODS: Sixty-nine consecutive patients were identified who had undergone staging of rectal cancer on CT. The imaging data were reviewed as axial images and then as MPR images (coronal and sagittal) perpendicular and parallel to the tumour axis. CT staging on axial and MPR images was then compared to histopathological staging. RESULTS: MPR images detected more T4 and T3 stage tumours than axial images alone. The overall accuracy of T-staging on MPR images was 87.1% versus 73.0% for axial images alone. The overall accuracy of N staging on MPR versus axial images was 84.8% versus 70.7%. There was a statistically significant difference in the staging of T3 tumours between MPR and axial images (p<0.001). CONCLUSION: Multidetector row CT has high accuracy for local staging of rectal cancer. Addition of MPR images to standard axial images provides higher accuracy rates for T and N staging of rectal cancer than axial images alone.  相似文献   

5.
目的探讨64层螺旋CT横断位结合多平面重建(MPR)对早期胃癌的检出价值。方法回顾性分析30例经病理证实的早期胃癌的CT影像特征,由2名有经验的放射诊断医师分别评估轴位及MPR重建图像对早期胃癌的检出率,意见不同时通过协商达成一致。结果30例患者中,轴位图像检出18例,其检出率18/30;结合MPR图像检出26例,检出率26/30,两者之间的检出率差异有统计学意义(P=0.020);单纯CT横断位图像T分期准确性为26.67%(8/30),结合MPR图像T分期准确性为63%(19/30),两者比较差异有统计学意义(χ2=8.148,P=0.004)。结论64层螺旋CT横断位结合MPR图像能提高早期胃癌的检出率及术前分期的准确性。  相似文献   

6.
目的:探讨CT和MRI在诊断大前庭水管综合征(LVAS)中的应用价值。方法:10例LVAS患者行CT和MRI检查,在CT多平面重组(MPR)图像上分别测量前庭水管(VA)中点最宽径及外口直径,并应用容积再现(VR)技术进行三维重组;MRI检查均使用3D-FIESTA序列,在MPR图像上分别测量内淋巴囊(ES)骨内部分中点最宽径及外口直径,并应用VR三维重组技术。2组中点最宽径及外口直径分别行相关性检验和配对t检验。结果:10例LVAS患者CT均显示双侧扩大的VA,MRI显示双侧扩大的ES。CT测得VA中点及外口平均直径分别为1.935和2.935 mm,MRI相应测量值为1.880和3.115mm.2组的这2项测量结果均具有相关性(P<0.05)。VR图像能立体直观地显示扩大的VA及ES。结论:CT和MRI检查均可以正确诊断LVAS,MPR及VR重组图像可清晰地显示扩大的VA和ES。  相似文献   

7.
Imaging of renal lesions: evaluation of fast MRI and helical CT   总被引:5,自引:0,他引:5  
The purpose of this study is to compare triphasic helical CT and fast MRI with respect to detection, characterization and staging of suspected renal masses. To achieve this triphasic helical CT (plain, corticonephrographic and tubulonephrographic phase) and MRI with fast T(1) weighted and T(2) weighted sequences were performed in 29 patients with a suspected renal lesion. Image quality, lesion characterization and lesion extent were assessed for both methods in all patients. The acquisition phase for CT and the image sequence for MRI offering the best image quality and best diagnostic information regarding renal parenchyma, renal vessels, detection of enlarged lymph nodes, and other abdominal organs were determined. Histologically confirmed renal cell carcinomas (n=18) were staged based on the Robson classification. Quantitative data were obtained from operator-defined regions of interest (ROIs) in all acquisition phases (CT) and all image sequences (MRI). For most criteria the rating of image quality for helical CT was generally higher as compared with fast MRI. CT and MRI detected all 24 histologically proven masses, while no false positive solid tumour was diagnosed with both imaging modalities. All three acquisition phases in CT and all applied image sequences in MRI were regarded as necessary in order to gain important diagnostic information. Altogether, 12 of 18 renal cell carcinomas (67%) were correctly staged by CT and MRI. Helical CT and fast MRI allow the correct detection and characterization of suspicious renal lesions. Both imaging modalities can be recommended for clinical routine application. Although the correct histological staging of renal cancer remains difficult for both imaging methods, both are excellent in providing the critical staging information needed before surgery. Helical CT offers a significantly shorter acquisition time to cover the entire abdomen.  相似文献   

8.
Bone scintigraphy has provided valuable data in the assessment and management of neoplastic disease since being first described in the early 1960s. There have been many developments in imaging techniques and radiopharmaceuticals over the years allowing more reliable detection of metastatic spread to bone. Other imaging modalities are also evolving roles in the detection of metastatic spread including computed tomography (CT), magnetic resonance imaging (MRI), and positron emission tomography (PET). Despite this, isotope bone scans continue to have a central role in detection and surveillance of bone metastases in breast and prostate cancer. Paralleling developments in imaging there have been enormous changes in the treatment options available for cancers of the breast and prostate that have metastasised to bone. Bone specific treatments including radionuclides and bisphosphonates as well as high dose chemotherapy provide potential improvement in disease control. There is also evidence that earlier treatment of bone metastases may prolong survival. This increases the need for efficient methods of detection and monitoring of disease. In this article we discuss the efficacy of bone scintigraphy in breast and prostate cancer from the point of view of staging, systematic follow-up of asymptomatic patients, evaluation of symptomatic patients and the assessment of response to therapy.  相似文献   

9.
Magnetic resonance imaging (MRI) is presently the modality of choice for the local staging of rectal cancer, with positron emission tomography (PET) being optional for the evaluation of colorectal cancer. Indeed, previous studies have demonstrated that liver MRI using hepatocyte‐specific contrast agents can provide high diagnostic performance in the detection of colorectal cancer liver metastases. Recently, however, whole‐body PET/MRI, which can provide information regarding both anatomy and metabolism, has been introduced to clinical imaging, and studies are under way to assess whether it can improve diagnostic performance for oncologic diseases as well as provide additional information regarding the disease phenotype and biology compared to conventional imaging modalities of computed tomography (CT), PET, or MRI. This review offers a brief overview of the technical considerations of the PET/MRI system, and the current status of imaging modalities in the staging of colorectal cancer. The potential of whole‐body PET/MRI to improve the performance of colorectal cancer staging and the results of several recent studies will be discussed, and workflow considerations of whole‐body PET/MRI for patients with colorectal cancer will be addressed. Level of Evidence: 5 J. Magn. Reson. Imaging 2017;45:21–35.  相似文献   

10.
We present cross-sectional imaging findings in eight patients with ureter tumors. Eight patients were examined by computed tomography (CT), seven by ultrasonography (US), and five by magnetic resonance imaging (MRI). All the lesions were detected by the three modalities. All modalities were accurate in excluding the periureteral invasion and lymphadenopathy in Stages 1 and 2 tumors. While CT and MRI identified the periureteral invasion and lymphadenopathy in four patients with advanced tumors, US failed to show the local invasion in three of four patients. Nevertheless, enlarged retroperitoneal lymph nodes could be detected sonographically in the three Stage 4 tumors. CT and MRI appear to have a high diagnostic sensitivity and staging accuracy in ureter tumors. Although US detects ureter tumors efficiently, this technique seems to be unreliable in showing local invasion in a substantial number of patients.  相似文献   

11.
Morphologic and functional imaging of malignant pleural mesothelioma   总被引:4,自引:0,他引:4  
Malignant pleural mesothelioma (MPM) is an aggressive tumor that arises from the pleura and frequently extends to adjacent structures. MPM cells produce and respond to many angiogenic factors, such as vascular endothelial growth factor (VEGF). VEGF expression in MPM is correlated with microvascular density, which is associated with poor survival. CT has been widely used as the primary imaging modality for the clinical evaluation of MPM. Major findings include nodular pleural thickening, unilateral pleural effusion, and tumor invasion of adjacent structures. CT tends to underestimate early chest wall invasion and peritoneal involvement and has well-known limitations in the evaluation of lymph node metastases. Perfusion CT can evaluate the microvasculature of tumors, while its disadvantages, such as high radiation exposure or side effects from iodinated contrast, limit its use in both research and clinical settings. MRI can provide additional information to CT. Because of its excellent contrast resolution, MRI is superior to CT, both in the differentiation of malignant from benign pleural disease, and in the assessment of chest wall and diaphragmatic involvement. Perfusion MRI is the most promising technique for the assessment of the tumor microvasculature. In MPM, therapeutic effects of chemotherapy can be monitored with perfusion MRI. It has been shown that FDG-PET is useful for the differentiation of benign from malignant lesions, for staging and monitoring metabolic response to therapy against MPM, and that it has prognostic value. An initial report on PET/CT imaging of MPM has shown increased accuracy of overall staging, improving the assessment of tumor resectability. PET/CT seems to be superior to other imaging modalities in detecting more extensive disease involvement, and identifying unsuspected occult distant metastases.  相似文献   

12.
A prospective study was undertaken to assess the ability of magnetic resonance imaging (MRI) to stage cervical carcinoma. Compared to computed tomography (CT), MRI showed a high degree of accuracy in correctly demonstrating involvement of the vagina, parametria and sidewalls, bladder, and lymph nodes but tended to overestimate disease in all of the categories studied. Large-scale studies comparing the two modalities are necessary because the most accurate staging of cervical carcinoma is crucial for selecting the best treatment protocols.  相似文献   

13.
In order to compare the advantages and failings of the current imaging procedures used for the staging of parotid masses, 121 patients were investigated: 30 with ultrasound (US) and CT, 55 with US and MRI, and 36 with US, CT and MRI. The accuracy of the three imaging modalities was evaluated in detecting parotid lesions; in assessing their location (intra- or extraglandular) and nature (benign or malignant); and in defining their intraglandular extent (superficial or deep lobe) as well as their relationship with surrounding structures. The imaging findings were related to the cytohistological data from US-guided biopsy or from surgical resection. In the 36 patients studied with all three modalities the diagnostic accuracy (excluding double errors in the same patient) was 77.7% for US, 86.1% for CT and 94.4% for MRI. US was thus shown to be less accurate than CT or MRI, and MRI not significantly superior to CT. US with fine-needle aspiration cytology should be the first-line imaging technique; CT and MRI have to be- considered for lesions more than 3 cm in diameter or for masses arising in the deep lobe of the gland. The results of this series show that MRI provides better results than CT in displaying the relationship of the mass with contiguous structures. Correspondence to: L. Grazioli  相似文献   

14.
OBJECTIVE: To evaluate the accuracy of multidetector computed tomography (CT) and magnetic resonance imaging (MRI) in staging and estimating renal carcinomas with caval thrombus. METHODS: Initially, 23 patients with suspected caval thrombi were admitted into this prospective study. Triphasic CT imaging was performed using a multidetector CT with a reconstructed slice thickness of 2 mm. 3D CT reconstructions were used to improve surgical planning. MRI protocol included: a transversal T1-weighted GE sequence with and without Gd-DTPA, a transversal T2-weighted respiratory-gated TSE, and a coronal T1-weighted GE sequence with Gd-DTPA and fat saturation. In addition, a multiphase 3D angiography was performed after Gd-DTPA injection. Patients were divided into 3 groups: caval thrombus below the insertion of the hepatic veins, within the intrahepatic vena cava, and intra-atrial extension. The results the tumor thrombus extension and staging results of 2 independent readers were correlated with surgical and histopathological staging. RESULTS: Of the 23 patients admitted, CT and MR scans of 14/13 patients respectively were correlated with histopathological workup. CT thrombus detection sensitivity and specificity for both readers was 0.93 and 0.8 respectively. MRI sensitivity and specificity for both readers was 1.0/0.85 and 0.75.Readers I and II evaluated the uppermost extension of the cranial tumor thrombus by both CT and MRI. CT and MR accuracy was 78% and 72%, 88% and 76% respectively. CONCLUSION: In cases of a suspected tumor thrombus, MRI and multidetector CT imaging showed similar staging results. Consequently, these staging modalities can be used to assess the extension of the tumor thrombus.  相似文献   

15.
Post transplant lymphoproliferative disease (PTLD) is a severe complication after solid organ or bone marrow transplantation. In pediatric transplant recipients PTLD is the most common malignancy. The aim of this study was to evaluate a possible role for positron emission tomography with [18F]-2-fluoro-2-desoxy-glucose (FDG) in the initial staging and in therapy monitoring of pediatric patients suffering from biopsy-proven CD20-positive PTLD after solid organ transplantation. Seven pediatric patients were included. All available imaging studies - CT (n=15), MRI (n=16) and PET/PETCT (n=16) - were reviewed on a lesion by lesion base. The performance of FDG-PET in the initial staging and during therapy with a chimeric anti-CD20 antibody was compared to conventional cross sectional imaging and correlated with the clinical outcome. FDG-PET identified all sites of disease as shown by CT/MRI and helped to clarify the significance of equivocal findings. The initial stage of disease was correctly identified by FDG-PET alone when compared to CT/MRI. During therapy, FDG-PET was superior to conventional cross-sectional imaging in the early evaluation of response.  相似文献   

16.
胃肠道肿瘤影像诊断技术进展有评价   总被引:2,自引:0,他引:2  
用于胃肠检查的影像学诊断技术有多种,最常用的方法有胃肠钡剂检查,CT和MRI,近年发展的新的技术有:螺旋CT口服法小肠造影,胃肠道螺旋CT三维重建,螺旋CT胃,结肠空气铸型成像;肠道MRI不成象,MR结肠造影,以及CT<MRI仿真内窥镜技术,各种新技术在胃肠道肿瘤诊断领域中发挥了作用,有助于胃肠道肿瘤的诊断和肿瘤侵犯范围的术前评估,本文概述了胃肠道各种影像检查方法的应用价值。并予以评价;辊注意的是:每一种影像检查手段都以其独特的成象原理显示各自的优越性,但也有其相对的局限性,因此,联合应用,互相补充,综合诊断是极为重要的。  相似文献   

17.
18-Flurodeoxyglucose Positron Emission Tomography with computed tomography (FDG PET/CT) and Magnetic Resonance Imaging (MRI) have higher sensitivity and specificity than whole-body X-ray (WBXR) survey in evaluating disease extent in patients with multiple myeloma (MM). Both modalities are now recommended by the Durie–Salmon Plus classification although the emphasis is more on MRI than PET/CT. The presence of extra-medullary disease (EMD) as evaluated by PET/CT imaging, initial SUVmax and number of focal lesions (FL) are deemed to be strong prognostic parameters at staging. MRI remains the most sensitive technique for the detection of diffuse bone marrow involvement in both the pre and post-therapy setting. Compression fractures are best characterized with MRI signal changes, for determining vertebroplasty candidates. While PET/CT allows for earlier and more specific evaluation of therapeutic efficacy compared to MRI, when signal abnormalities persist years after treatment. PET/CT interpretation, however, can be challenging in the vertebral column and pelvis as well as in cases with post-therapy changes. Hence, a reading approach combining the high sensitivity of MRI and superior specificity of FDG PET/CT would be preferred to increase the diagnostic accuracy. In summary, the established management methods in MM, mainly relying on biological tumor parameters should be complemented with functional imaging data, both at staging and restaging for optimal management of MM.  相似文献   

18.
Schmidt GP  Schmid R  Hahn K  Reiser MF 《Der Radiologe》2004,44(11):1079-1087
Tumor staging according to the TNM-system influences prognosis and therapeutical options of patients with a malignant disease. It is the challenge of diagnostic imaging to depict the exact localization of the primary tumor and to detect or rule out lymph node involvement or distant metastases. In doing so, the complete body anatomy should be covered with a modality that offers high sensitivity and specificity. As these requirements could not or only partially be achieved by previous ordinary procedures, the use of multiple different modalities became necessary. Last but not least, in consideration of the costs it would be preferable to replace this cascade of different modalities by a "whole body examination", preconditioned that the same accuracy is achieved.With PET/CT and whole-body MRI, two newly available promising methods for a systemic tumor staging have been developed. First experiences indicate PET/CT as a method of first choice. With the introduction of new whole-body MRI scanners using parallel imaging technique (iPAT) and free table movement, MRI plays a more and more important role in whole body tumor staging.  相似文献   

19.
Multiple myeloma (MM) is the second most common type of hematological disease with its incidence rising in the elderly. In MM, the extent of the bone disease increases both morbidity and mortality. The detection of lytic bone lesions on imaging, especially computerized tomography (CT) and magnetic resonance imaging (MRI) is crucial to separate asymptomatic from symptomatic MM patients even when no clinical symptoms are present. Although radiology is essential in the staging and management of patients with MM there is still high variability in the choice between MRI and CT. In addition, there is still suboptimal agreement among readers. The potential of medical imaging in MM is largely under-evaluated: artificial intelligence, radiomics and new quantitative methods to report CT and MRI will improve imaging usage.  相似文献   

20.
Magnetic resonance imaging of osteonecrosis   总被引:13,自引:0,他引:13  
Because the available preliminary data strongly indicate that MRI is accurate in diagnosing osteonecrosis, MRI of the hips is recommended in patients suspected of having osteonecrosis, especially if other diagnostic studies are equivocal. MRI also may be useful in following patients who have strong risk factors for osteonecrosis, such as corticosteroid therapy, femoral neck fracture, traumatic femoral head dislocation (Fig. 13), slipped capital femoral epiphysis (Fig. 14), and congenital hip dislocation. In diseases such as systemic lupus erythematosus, both hips eventually may become involved in 50 to 80 per cent of cases. Therefore, the unaffected hip of patients with systemic lupus erythematosus and unilateral nontraumatic osteonecrosis of the hip should be monitored regularly with MRI. The hope is that early diagnosis and treatment of femoral head osteonecrosis will prevent the relentless progression to subchondral collapse and disabling arthropathy. MRI also may be useful in staging patients known to have osteonecrosis. The ability of MRI to image directly in multiple planes facilitates the determination of the volume and location of infarcted segments of bone. This information is important in planning any of the surgical procedures used relatively early in the disease, such as core decompression, rotational osteotomy, or bone graft. Moreover, MRI may prove helpful in evaluating the effectiveness of any therapeutic intervention.  相似文献   

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