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81.
目的:探讨应用对比增强谐波超声方法显像肝转移癌及其血流特征。方法:16例20个肝内局灶转移癌。将24m1造影剂SonoVue经前臂静脉注入后进行对比增强谐波超声方法(ECI)扫描,并连续观察记录病灶局部影像,共4min,历经动脉期、门脉期、实质期。结果:10/20个病灶于血管期呈现绕病变周边部的近完整或不完整的细环状增强;7/20个病灶于整个观察期未显示血流征象;2/20个病灶内部少许不典型点状、细条状血流分布显示于血管期;1/20个病灶于常规超声检查中未显像,实质期局部无增强,在周围正常组织增强映衬下呈类“黑洞征”。结论:血管期的肿瘤血供形式具有重要的鉴别意义即肝转移癌在血管期呈环状增强或无增强,实质期局部无增强。超声造影剂的使用可以提高肝转移癌的检出率。 相似文献
82.
There is a growing interest in the measurement of quality of life as an important marker of health outcomes. The General Well-Being Index (GWBI) is a quality of life measure that has been specifically designed to assess psychological distress rather than physical incapacitation. Previous studies using the GWBI have mainly focussed on clinical samples (e.g., depressed patients). The aim of the current study was to examine the psychometric properties of the GWBI in a non-clinical population. Using data gathered from 447 first year University students, the GWBI was found to have excellent psychometric properties. Both internal consistency and test-retest reliability were high, and the concurrent and construct validity of the measure were sound. Factor analysis revealed three significant factors, which were labelled 'general mood/affect', 'life satisfaction/vitality', and 'poor physical health/somatic complaints'. Limitations to the present study are further discussed. 相似文献
83.
Treatment of unresectable lung metastases with transpulmonary chemoembolization: preliminary experience 总被引:5,自引:0,他引:5
Transpulmonary chemoembolization (TPCE) was evaluated as a new treatment for unresectable lung metastases. Institutional review board approval and patient consent were obtained. In 23 patients, 26 lung metastases of different origins were treated locally by using a transpulmonary approach. After femoral vein puncture, tumor-supplying pulmonary arteries were selectively explored, and 5-10 mg mitomycin C and 5-10 mL iodized oil and microsphere particles were applied with balloon protection. Diagnosis and follow-up (3-month intervals) were performed with unenhanced and contrast material-enhanced computed tomography (CT). Treatment was well tolerated in all patients, with no major side effects or complications. As indicated by using morphologic criteria, volume regression of embolized areas was achieved in eight patients, while stable disease was revealed at follow-up in six patients. In nine patients, progression of treated intrapulmonary metastases was recorded. TPCE could be a well-tolerated palliative treatment option in patients with pulmonary metastases. 相似文献
84.
Khan MF Herzog C Landenberger K Maataoui A Martens S Ackermann H Moritz A Vogl TJ 《European radiology》2005,15(1):118-126
The purpose of this study was to investigate the image quality of coronary artery bypass graft visualization in 4- and 16-row multidetector CT using multiple imaging reformations. Material and Methods: One hundred sixteen patients underwent CT examination of the heart after receiving CABG. Group A (n=58) received 4-row MDCT; group B (n=58) received 16-row MDCT. Various bypass types such as LITA to LAD and venous grafts to the RCA and RCX were included in the study. A five-point Likert scale was used to grade image quality. Each bypass was reviewed under different imaging reformations: thin slap maximum intensity projection (MIP thin), multiplanar reformation (MPR) and volume rendering technique (VRT). Special attention was paid to the delineation of the distal anastomosis. Interobserver correlation was determined. Results: From 289 bypass grafts examined, 279 (96.54%) were classified as patent and 10 (3.46%) as not patent. Except for the distal anastomosis, 16-row MDCT showed significantly better results for all segments of bypasses. Comparison of reformations within group A and B showed that MIP thin (P<0.05) and VRT (P<0.05) displayed better visualization as compared to MPR. Conclusion: Significantly better imaging of all bypass types is possible using 16-row MDCT as compared to 4-row MDCT. Assessment of the distal anastomosis yields no difference between 4- and 16-row technology.This revised version was published online in October 2004 with a correction to the article title. 相似文献
85.
Luboldt W Tryon C Kroll M Toussaint TL Holzer K Hoepffner N Vogl TJ 《European radiology》2005,15(2):247-253
The purpose of this feasibility study was to design and test an algorithm for automating mass detection in contrast-enhanced CT colonography (CTC). Five patients with known colorectal masses underwent a pre-surgical contrast-enhanced (120 ml volume 1.6 g iodine/s injection rate, 60 s scan delay) CTC in high spatial resolution (16-slice CT: collimation: 16×0.75 mm, tablefeed: 24 mm/0.5 s, reconstruction increment: 0.5 mm). A CT-density- and volume-based algorithm searched for masses in the colonic wall, which was extracted before by segmenting and dilating the colonic air lumen and subtracting the inner air. A radiologist analyzed the detections and causes of false positives. All masses were detected, and false positives were easy to identify. Combining CT density with volume as a cut-off is a promising approach for automating mass detection that should be further refined and also tested in contrast-enhanced MR colonography. More information under . 相似文献
86.
Traumatic injuries of the pelvis and thoracic and lumbar spine: does thin-slice multidetector-row CT increase diagnostic accuracy? 总被引:2,自引:0,他引:2
Herzog C Ahle H Mack MG Maier B Schwarz W Zangos S Jacobi V Thalhammer A Peters J Ackermann H Vogl TJ 《European radiology》2004,14(10):1751-1760
The objective is to evaluate different multidetector-row CT (MDCT) strategies for adequate classification of spinal and pelvic injuries. Seventy intubated patients after multiple trauma underwent conventional radiography (CR) and MDCT. Examinations included the pelvis (P), the lumbar spine (LS) and the thoracic spine (TS). Conventional radiographs, 3-mm (CT5) and 5-mm scans (CT3) and 3-mm and 5-mm scans combined with MPR (CT3R/CT5R) were compared to surgery, autopsy and clinical course. MDCT led to significantly better results than CR (P<0.01). Correlation coefficients were r=1.0 (CT3R), r=0.96 [TS] to r=1.0 [P/LS] (CT5R), r=0.8 [P] to r=1.0 [TS] (CT3), r=0.80 [P] to r=0.86 [TS] (CT5) and r=0.3 [TS] to r=0.69 [P] (CR). Fractures were identified by CT3R in 100% of cases, by CT5R in 95%, by CT3 in 90% [P]–100% [TS], by CT5 in 83.3% [LS]–90% [P] and by CR in 57.1% [TS]–87.2% [P]. Unstable fractures were identified in 100% by CT3R, CT5R and CT3, 85.7% [TS]–100% [P/LS] by CT5 and 57.1% [TS]–80% [P] by CR. Only overlapping thin-slice multiplanar reformation allows for an adequate classification of spinal and pelvic injuries and thus is highly emphasized in patients after severe blunt trauma. 相似文献
87.
Background
The adiposity rebound is the second rise in body mass index that occurs between 3 and 7 years. An early age at adiposity rebound is known to be a risk factor for later obesity. The aim here is to clarify the connection between the age at rebound and the corresponding pattern of body mass index change, in centile terms, so as to better understand its ability to predict later fatness. 相似文献88.
Hinterwimmer S von Eisenhart-Rothe R Siebert M Welsch F Vogl T Graichen H 《Clinical biomechanics (Bristol, Avon)》2004,19(7):704-710
BACKGROUND: Patients with genu varum of the knee and moderate to severe osteoarthritis often suffer from additional symptoms of the patello-femoral joint. These patients have a poor prognosis following high tibial osteotomy. It is unclear whether varus knees with only mild femoro-tibial osteoarthritis are also associated with alterations of patella biomechanics, and affect the prognosis of intended high tibial osteotomy. METHODS: Fifteen patients with genu varum and mild osteoarthritis and 15 healthy volunteers were assessed in an open MRI-scanner. 3D-GRE sequences of the knee were obtained in 0 degrees, 30 degrees and 90 degrees with and without activity of the extensor muscles. After segmentation of patella, femur, tibia and the adjacent cartilage, a patella-based local coordinate system was established. Femoral and tibial reference points allowed definition of the spatial position of the patella. Contact areas were defined by intersection of opposing cartilage volumes. FINDINGS: No significant differences in patella kinematics and patello-femoral contact areas could be found (P > 0.05) between varus knees with mild osteoarthritis and healthy knees either at different flexion angles or under extending muscle activity. INTERPRETATION: In knees with genu varum and mild medial osteoarthritis we could detect no alterations in patello-femoral kinematics. Since the alterations of patients with genu varum and mild osteoarthritis are restricted to the medial femoro-tibial joint high tibial osteotomy might be successful. 相似文献
89.
90.
Leeb SN Vogl D Grossmann J Falk W Schölmerich J Rogler G Gelbmann CM 《The American journal of gastroenterology》2004,99(2):335-340
OBJECTIVES: A central event during wound repair is the migration of activated fibroblasts to the wound area. Thus far, the mechanisms inducing migration of colonic lamina propria fibroblasts (CLPF) have not been studied in detail. Previously, we have shown that CLPF secrete factors that are essential to their ability to migrate in response to different growth factors. METHODS: Primary human CLPF were obtained from endoscopic biopsies or surgical specimens taken from normal mucosa areas of patients undergoing surveillance colonoscopy or surgery for colorectal carcinoma. Migration assays of CLPF were performed in the modified 48-well Boyden chamber. RESULTS: Conditioned medium of CLPF collected after 24-h stimulated migration of CLPF (22 +/- 2 cells/ hpf). Filtration of conditioned medium through a 300-kDa filter reduced the migration-inducing potential in subsequent migration assays to 2 +/- 1 cells/hpf, filtration through a 100-kDa filter abolished migration of CLPF completely, indicating that large molecules such as extracellular matrix components could be responsible for the induction of CLPF migration. Enzyme-linked immunosorbent assays revealed the presence of fibronectin in conditioned medium (17.3 microg/ml). Immunoprecipitation of fibronectin in conditioned medium of CLPF reduced the migration-inducing potential by 63%. Addition of fibronectin to fibronectin-depleted conditioned medium reconstituted the migration. Dose-response assays with fibronectin (1-100 microg/ml) diluted in nonconditioned medium induced migration of CLPF in a dose-dependent manner. Maximum migration was induced with 25 microg/ml fibronectin (37 +/- 5 cells/hpf). CONCLUSION: Fibronectin is an autocrine and paracrine factor essential for intestinal fibroblast migration. Fibronectin induces migration of intestinal fibroblasts and is essential for their ability to migrate in response to different growth factors. A detailed understanding of the regulation of the migration of intestinal fibroblasts is necessary to gain further insights in the pathophysiology of stricture and fistula formation. 相似文献