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91.
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
92.
Huppertz A Balzer T Blakeborough A Breuer J Giovagnoni A Heinz-Peer G Laniado M Manfredi RM Mathieu DG Mueller D Reimer P Robinson PJ Strotzer M Taupitz M Vogl TJ;European EOB Study Group 《Radiology》2004,230(1):266-275
PURPOSE: To evaluate the safety and efficacy of gadoxetic acid disodium-enhanced magnetic resonance (MR) imaging for the detection of focal liver lesions, with results of histopathologic examination and/or intraoperative ultrasonography used as a standard of reference. MATERIALS AND METHODS: One hundred sixty-nine patients who were known to have or suspected of having focal liver lesions and were scheduled for liver surgery were included in this study. Results in 131 patients could be included in the efficacy analysis. MR imaging was performed before and immediately and 20 minutes after bolus injection of 0.025 mmol/kg of the liver-specific hepatobiliary contrast agent gadoxetic acid. T1-weighted gradient-echo (with and without fat saturation and including dynamic data sets) and T2-weighted fast spin-echo/turbo spin-echo sequences were performed. All images were evaluated on site and by three independent and blinded off-site reviewers. Lesion matching based on the standard-of-reference results was performed. Differences in lesion detection with precontrast and with postcontrast MR images were assessed with the two-sided Wilcoxon signed rank test. RESULTS: Gadoxetic acid was well tolerated. In the on-site review, the number of patients in whom all lesions were correctly matched increased from 89 of 129 patients at precontrast MR imaging to 103 of 129 patients at postcontrast MR imaging. In the off-site evaluation, the number of patients in whom all lesions were correctly matched and the corresponding sensitivity values increased from 72 (55.8%), 68 (52.7%), and 66 (51.2%) with the precontrast images to 88 (68.2%), 69 (53.5%), and 76 (58.9%) with the postcontrast images for readers 1, 2, and 3, respectively. Two of the three blinded readers showed a statistically significant difference in lesion detection between precontrast and postcontrast MR imaging (P <.001 and P =.008). A large number of additionally correctly detected and localized lesions were smaller than 1 cm. CONCLUSION: MR imaging with gadoxetic acid is safe and improves lesion detection and localization. 相似文献
93.
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
94.
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
95.
96.
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
97.
Transarterielle Chemoembolisation (TACE) von Lebermetastasen – Ein palliativer Therapieansatz 总被引:1,自引:0,他引:1
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
98.
Kirchner TH Seipelt G Vogl TJ 《R?ntgenpraxis; Zeitschrift für radiologische Technik》2001,54(4):148-151
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
99.
CT-guided percutaneous core biopsies of pulmonary lesions. Diagnostic accuracy, complications and therapeutic impact 总被引:7,自引:0,他引:7
Lopez Hänninen E Vogl TJ Ricke J Felix R 《Acta radiologica (Stockholm, Sweden : 1987)》2001,42(2):151-155
Purpose: To evaluate the diagnostic accuracy, complications, and therapeutic impact of CT-guided percutaneous core biopsies of pulmonary lesions.Material and Methods: Seventy-nine patients underwent diagnostic CT-guided percutaneous core biopsies of pulmonary lesions between July 1995 and March 1999. Evaluation included corresponding clinical data, pathologic results, and therapeutic consequences.Results: There were 29 benign and 50 malignant lesions. Percutaneous core biopsy had an overall diagnostic accuracy of 95%. For malignant lesions, core biopsy was positive in 48 patients (sensitivity 96%), and for benign lesions, in 27 (sensitivity 93%). There were no false-positive findings. Pneumothoraces were observed in 19 patients (24%) and 4 of them required a chest drain (5%). There were no hematothoraces or major bleeding complications; however, postinterventional local hemorrhages were observed in 23 patients (29%). No hemoptysis was noted.Conclusion: Percutaneous core biopsies of pulmonary lesions offer excellent diagnostic accuracy for both benign and malignant pulmonary lesions at a low complication rate. 相似文献
100.
The fate of the contact sensitizer fluorescein isothiocyanate was traced by means of fluorescence spectrophotometry and flow cytometry. The hapten applied to one ear rapidly entered the circulation by way of local lymphatics and blood vessels. It was dispersed for several hours essentially as free hapten, released from a reservoir left behind at the site. Hapten molecules coupled to plasma proteins while circulating and reacted with white blood cells. Total cells of regional lymph nodes, spleen, and distant lymph nodes became fluorescent in successive order. Fluorescence of CD11c-positive dendritic cells exceeded significantly that of lymphoid cells. Total spleen cells and total nonregional lymph node cells were shown in vitro to drive committed lymph node cells to proliferation. The mechanism disclosed is proposed to counterbalance the action of epidermal Langerhans cells for regulation of contact hypersensitivity. 相似文献