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41.
42.
Ghanem N Uhl M Müller C Elgeti F Pache G Kotter E Markmiller M Langer M 《European radiology》2006,16(11):2533-2541
In this study we evaluated magnetic resonance imaging (MRI) in trauma patients for assessing traumatised adjacent discs of
fractured vertebrae before dorsoventral stabilisation. In a prospective study, MRI of 54 discs was performed with a 1.5-T
MRI unit. The preoperative MRI with sagittal T1-W-SE and T2-W-TSE was compared to intraoperative discography, which was carried
out on both intervertebral discs adjacent to the fractured vertebrae. Signal alterations, morphological changes in the adjacent
discs, fractured vertebrae and associated ligament injuries were evaluated. In 47/54 (87%) of the intervertebral discs, the
results of both imaging findings were concordant. The discs adjoining vertebral fractures were normal in 18 cases. Regarding
the positive concordant imaging findings, MRI and discography revealed traumatised adjacent cranial and caudal discs in 22
discs. In 7 cases, only the cranial adjacent disc was affected. Moreover, 17 cases of intradiscal bleeding, 13 intraosseous
herniations into the fractured vertebrae and 20 anuluar tears were visualised in MRI. Associated ligament injuries were detected
in 18 cases. Findings were discordant in eight discs. In six discs, MRI was abnormal, demonstrating signal alterations suggestive
of positive imaging findings, whereas discography demonstrated no disc injury. MRI failed to detect disc injury in two discs,
whereas discography was positive, showing an irregular intradiscal contrast media distribution. MRI, as a non-invasive method
for assessing fractures of the thoraco-lumbar spine, may detect traumatised adjacent intervertebral discs. MRI is superior
to intraoperative discography. The performance of MRI of the thoraco-lumbar spine is recommended before dorsoventral stabilisation
in trauma patients, as it can reveal additional preoperative information such as fractures, disc and associated ligament injuries. 相似文献
43.
Bley TA Kotter E Saueressig U Springer OS Fisch D Ghanem NA Langer M 《AJR. American journal of roentgenology》2003,181(6):1487-1490
OBJECTIVE: The aim of this study was to compare the diagnostic quality of paper prints with film copies in a sample of observers who were trying to detect small coin lesions on radiographs of a phantom. MATERIALS AND METHODS: The phantom consisted of 60 high-contrast and 60 low-contrast test objects, half of which had holes in them. Diameter and depth of the holes varied from 0.5 mm to 2 mm. Fifteen radiographs were obtained from different areas of the test objects. Film copies and paper prints were made using high-quality printers. Five observers independently evaluated 1,800 high-contrast and 1,800 low-contrast images. Data were evaluated using the well-established receiver operating characteristic methodology. RESULTS: The mean area under the curve rated 0.863 for paper prints (0.859 for high contrast and 0.860 for low contrast) and 0.926 for laser films (0.937 for high contrast and 0.913 for low contrast). The difference between the two imaging techniques was statistically significant for both high- and low-contrast lesions (p < 0.05). CONCLUSION: Detection of small coin lesions on radiographs of a phantom was significantly less sensitive on paper prints than on film. We found paper prints less acceptable for the diagnosis of small-sized lesions. 相似文献
44.
Diagnostic value of MRI in comparison to scintigraphy, PET, MS-CT and PET/CT for the detection of metastases of bone 总被引:8,自引:0,他引:8
Ghanem N Uhl M Brink I Schäfer O Kelly T Moser E Langer M 《European journal of radiology》2005,55(1):41-55
The initial localization of metastases in the bone in patients with solid tumors has a relatively good prognosis in comparison with visceral metastasization. The early detection of bone marrow metastases allows for a rapid initiation of therapy and a subsequent reduction in the morbidity rate. Modern MRI is superior to the 30-year-old skeletal scintigraphy and bone marrow scintigraphy with respect to sensitivity, specificity, as well as the extent of osteal metastasis. MRI provides substantial, therapy-relevant additional information. MSCT plays an important role in the management of cancer patients in clinical routine and gives an excellent survey of the axial skeleton by demonstrating osteolytic and osteoblastic metastases. Extensive comparative studies of MRI with 18F-FDG-PET and 18F-fluoride-PET have not yet been carried out. Whole body MRI is a very promising new staging method for the oncological diagnosis of solid tumors and the detection of osteal metastases. The adoption of 18F-FDG-PET and 18F-fluoride-PET FDG as well as the side by side PET-CT image fusion and the two in one PET/CT examinations appears to be slightly less sensitive to whole body MRI in the detection of osteal metastases. Larger, prospective multicenter studies are necessary to establish these as new, promising methods for the detection of osteal metastases. 相似文献
45.
Ghanem N Altehoefer C Högerle S Nitzsche E Lohrmann C Schäfer O Kotter E Langer M 《European journal of radiology》2005,54(2):264-270
PURPOSE: We evaluated the diagnostic accuracy of magnetic resonance imaging (MRI) and positron emission tomography (PET) for detection of liver metastases in malignant melanoma. MATERIAL AND METHODS: Thirty-five patients with 39 combined unenhanced MRI and fluorine-18 deoxyglucose (F-18 FDG) PET scans were prospectively studied. In discordant imaging findings final diagnosis was proven by clinical follow-up >6 months and demonstration of progressive liver metastases by at least one imaging method. Sensitivities and specificities were compared and the influence of lesion size and melanin content on diagnostic accuracy was determined. RESULTS: MRI and PET were concordantly negative for presence and number of liver metastases in 28 patients and positive in four patients. PET and MRI were false positive in one patient each. In one patient MRI showed a single metastases not seen by PET and in one patient MRI demonstrated more metastases at the first examination. In follow-up investigations MRI revealed more metastases than PET in both patients. The sensitivities for lesion detection were 47% (16/34) for PET and 100% for MRI. Lesion detectability by PET was related to lesion size (P < 0.0001) but not to melanin content. CONCLUSION: MRI is more sensitive in the detection of liver metastases in patients with malignant melanoma. Small lesions are easily missed by PET, while melanin content does not influence detectability by PET. 相似文献
46.
Elias Melhem Ayman Assi Rami El Rachkidi Ismat Ghanem 《Journal of children's orthopaedics》2016,10(1):1-14
Purpose
In 1992, Georges Charpak invented a new type of X-ray detector, which in turn led to the development of the EOS® 2D/3D imaging system. This system takes simultaneous anteroposterior and lateral 2D images of the whole body and can be utilized to perform 3D reconstruction based on statistical models. The purpose of this review is to present the state of the art for this EOS® imaging technique, to report recent developments and advances in the technique, and to stress its benefits while also noting its limitations.Methods
The review was based on a thorough literature search on the subject as well as personal experience gained from many years of using the EOS® system.Results
While EOS® imaging could be proposed for many applications, it is most useful in relation to scoliosis and sagittal balance, due to its ability to take simultaneous orthogonal images while the patient is standing, to perform 3D reconstruction, and to determine various relationships among adjacent segments (cervical spine, pelvis, and lower limbs). The technique has also been validated for the study of pelvic and lower-limb deformity and pathology in adult and pediatric populations; in such a study it has the advantage of allowing the measurement of torsional deformity, which classically requires a CT scan.Conclusions
The major advantages of EOS® are the relatively low dose of radiation (50–80 % less than conventional X-rays) that the patient receives and the possibility of obtaining a 3D reconstruction of the bones. However, this 3D reconstruction is not created automatically; a well-trained operator is required to generate it. The EOS® imaging technique has proven itself to be a very useful research and diagnostic tool.47.
Shamloul R Ghanem HM Salem A Kamel II Mousa AA 《International journal of impotence research》2004,16(1):78-79
The aim of this work is to assess the value of penile duplex in the prediction of intracavernous drug-induced ischemic priapism. A total of 400 patients with erectile dysfunction were evaluated before and after diagnostic intracavernous injection of a trimix solution (papaverine+phentolamine+PGE1) using color Doppler sonography. In all, 29 patients experienced sustained rigid erections for more than an hour. Patients were further divided into two groups. Group A included patients with spontaneous resolution of their rigid erection within 3 h (10/29) and group B included patients with priapism (19/29) that did not resolve within 3 h. In group A, patients had minimal cavernous artery blood flow within the first hour postinjection, that increased with relief of their erection. Group B patients had no blood flow in their cavernous artery an hour after intracavernous injection and for 6 h later. The disappearance of blood flow in the cavernous artery after an hour of sustained rigid erection predicted priapism with 100% specificity and sensitivity. The persistent absence of cavernous artery blood flow for more than an hour, as detected by color Doppler ultrasound, is an objective predictor of priapism. This may guide early intervention to resolve the prolonged erection. 相似文献
48.
Percutaneous radiofrequency coagulation of osteoid osteoma in children and adolescents 总被引:5,自引:0,他引:5
Ghanem I Collet LM Kharrat K Samaha E Deramon H Mertl P Dagher F 《Journal of pediatric orthopedics. Part B》2003,12(4):244-252
The purpose of this paper was to evaluate the effectiveness of percutaneous radiofrequency ablation of osteoid osteoma in children and adolescents. Twenty-three patients aged 4.5-19.5 years were retrospectively reviewed. All patients with lower limb lesions were able to bear full weight on their operated limb immediately after the procedure, and to resume their daily activities within 24-48 h. Pain disappeared immediately after surgery in 21 cases, and in lower limb lesions the gait was back to normal after an average of 5 days. No septic or neurovascular complications were observed. At an average follow-up of 3.5 years, all the patients including two cases of initial failure were free of pain and had a normal gait. Clinical healing was confirmed by computed tomography and bone scan performed in 12 cases. This precise and minimally invasive method is safe, effective and associated with reduced health care resources. It could be recommended as the treatment of choice for osteoid osteoma of the limbs in children and adolescents. 相似文献
49.
王文志 杨定焯 蒋建军 吴涛 程晓光 周琦 卓铁军 张华俦 项静 王洪复 区品中 刘建立 徐苓 黄公怡 黄琪仁 HS Barden LS Weynan KG Fqukner 孟迅吾 《中国神经再生研究》2008,12(50):9997-10000
背景: 不同地区骨峰值和标准差不同,对骨质疏松诊断率有较大影响。探讨建立一完整数据库为中国人骨质疏松诊断准确性提供依据。
目的:探讨青年人腰椎骨密度和标准差正常参考值影响骨质疏松症检出率的程度。
设计、时间及地点:调查分析,于1997-01/1999-12分别在北京、上海、广州、南京、嘉兴和成都市完成。
对象:采用前瞻性及回顾性方法对全国6个中心骨密度参考数据库中11 418人进行调查统计分析;男3 666人,女7 752人;年龄20岁~90岁;分别来自北京(2 385人)、广州(1 178人)、上海(1 404人)、南京(2 938人)、成都(1 425人)、嘉兴(2 088人),受试者来源于社区调查、健康体检和健康志愿者。
方法:用GE-Lunar公司的DXA仪测量骨密度,调查全国6个中心11 418人L2~L4腰椎后前位和髋部骨密度,建立了骨密度参考数据库。6个中心的仪器内部精度0.3%~0.7%,仪器间的精度1.1%。
主要观察指标:①6个中心不同年龄组腰椎骨密度分布。②青年人群骨密度及其标准差值对骨质疏松症检出率的影响。
结果:中国汉族女性以腰椎进行骨质疏松症诊断的青年人群的骨密度和标准差值,6个中心,最大差值分别为0.098 g/cm2和0.027 g/cm2。用6个中心及总体各自的青年人平均骨密度和标准差值为参考标准,对同一人群计算T-score和获得的骨质疏松症检出率不相同;发现青年人平均骨密度每变化0.01 g/cm2,则骨质疏松症检出率变化1.6%(呈正相关),其标准差值每变化 0.01 g/cm2,则骨质疏松症检出率变化4%(呈负相关)。
结论:青年人平均骨密度和标准差值不同引起骨质疏松症检出率也不相同。为了让不同中心的骨质疏松症检出率有可比性,建议同一个类型的骨密度仪,同一个种族,同一个地区用一个设计较完善大样本的参考数据库,以其青年人正常参考值计算T-score。 相似文献
50.
Paula Moynihan Mark Thomason Angus Walls Katherine Gray-Donald Jose A. Morais Henry Ghanem Stephanie Wollin Janice Ellis Jimmy Steele James Lund Jocelyne Feine 《Journal of dentistry》2009