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81.
Vogl TJ  Wetter A  Lindemayr S  Zangos S 《Radiology》2005,234(3):917-922
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   
82.
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   
83.
Autocrine fibronectin-induced migration of human colonic fibroblasts   总被引:3,自引:0,他引:3  
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   
84.
We present laser-induced thermotherapy (LITT) of primary and secondary lung tumors analysing indications and technical concepts. Thirty patients with lung metastases of different primary tumors (n=24) as well as localized lung tumors (n=6) were prospectively treated in 41 sessions using laser-induced thermotherapy (LITT). An MR-compatible puncture system was used with direct puncture technique. The puncture was performed via CT guidance in care vision technique. Eight patients were thermoablated using MR tomographical monitoring, 22 patients using CT monitoring. Local therapy effects, tumor control rate, side effects, complications, and survival were evaluated. In 74% of cases (28/38 lesions) of 24 patients with lung metastases and in all cases of the 6 patients with lung carcinoma a complete local ablation could be achieved. The complication rate (pneumothorax) was 9,8%. One patient with bronchial carcinoma had to be thoracotomized and resected. 93% of the patients are still alive. Percutaneous LITT of lung tumors permits a complete ablation of lung metastases and lung carcinomas with a low complication rate. Indications for the procedure were defined for patients with no more than 5 metastases up to 3 cm in size.  相似文献   
85.
Keim S  Mack M  Vogl T  Windolf J 《Der Unfallchirurg》2003,106(2):127-135
PURPOSE: This prospective study was aimed at evaluating the clinical impact of magnetic resonance imaging (MRI) vs conventional radiographs in the early diagnosis of acute wrist fractures.The influence of MRI on the period of being unable to work was demonstrated. MATERIALS AND METHODS: MRI was performed within a mean of 6.6 days after initial radiographs in 54 patients (56 wrists) with clinical suspicion of wrist fractures and normal plain or indistinct radiographs. MRI findings were read without knowledge of the initial radiographs. RESULTS: In 31 of 56 wrists MRI findings resulted in a change of diagnosis.There was a false positive diagnosis on plain radiographs in nearly one-half ( n=25) of the cases,whereas only six cases had false negative results. In 28 cases MRI allowed the detection of additional injuries of soft tissues. In 35 of 56 cases radiological follow-up was no longer necessary. In 22 of 54 patients the period of immobilization could be shortened or treatment discontinued ( n=18).The period of being unable to work was shortened in 16 of 54 patients, while in 7 of 54 patients this time span had to be prolonged for therapeutic reasons. In 31 of 54 patients MRI-based therapeutic consequences had no influence on the period of being unable to work. CONCLUSION: Our results show a high clinical impact of MRI in the detection of acute wrist fractures.Early MRI is able to reduce economic costs due to efficient therapeutic treatment and shortened periods of being unable to work.We recommend MRI immediately on the day of trauma in the presence of clinical suspicion and equivocal plain radiographs  相似文献   
86.
Galactography should only be performed if there is spontaneous bloody or serous discharge from a single lactiferous duct of one breast. If this is observed, only pathologic processes instead of normal breast tissue are removed upon surgery and there is a close correlation between radiologic results and pathologic findings. Galactography localizes intraductal pathologic processes precisely and thus contributes to minimal volume surgery.  相似文献   
87.
88.
Performance of Web-based image distribution: client-oriented measurements   总被引:2,自引:1,他引:1  
The aim of this study was to define a clinically suitable personal computer (PC) configuration for Web-based image distribution and to assess the influence of different hard- and software configurations on the performance. Through specially developed software the time-to-display (TTD) for various PC configurations was measured. Different processor speeds, random access memory (RAM), screen resolutions, graphic adapters, network speeds, operating systems and examination types (computed radiography, CT, MRI) were evaluated, providing more than half a million measurements. Processor speed was the most relevant factor for the TTD; doubling the speed halved the TTD. Under processor speeds of 350 MHz, TTD mostly remained above 5 s for 1 CR or 16 CT images. Here Windows NT with lossy compression were superior. Processor speeds of 350 MHz and over delivered TTD <5 s. In this case Windows 2000 and lossless compression were preferable. Screen resolutions above 1280×1024 pixels increased the TTD mainly for CR images. The RAM amount, network speed and graphic adapter did not have a significant influence. The minimum threshold for clinical routine is any standard off-the-shelf PC better than Pentium II 350 MHz, 128 MB RAM; hence, high-end PC hardware is not required.  相似文献   
89.
Metastatic involvement of the liver determines the treatment. Hepatic artery chemoembolization (TACE) represents a safe palliative treatment for patients with unresectable liver metastases. Technical treatment, indication and results of the TACE are reported. The results of TACE depend on primary cancer, size and vascularisation of the hepatic tumors. Our results with out patient treatment of 245 patients prove that TACE results in a extremely low rate of side effects. Combination of TACE with local ablative treatment may present potentially curative treatment option for unresectable tumors.  相似文献   
90.
We report on a patient suffering from Erdheim-Chester-disease (ECD). ECD represents a very rare entity with lipogranulomatosis of mesenchymal origin. The most common radiological manifestation is the involvement of the long bones of the extremities. Here we find sclerosis of the spongiosa combined with a thinning of cortical structures. This often results in a small crack of hyperlucency between corticals and spongiosa. Our case demonstrates an involvement of the craniofacial part of the skull showing sclerosis of the upper jaw bone. This manifestation has not yet been reported in the literature.  相似文献   
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