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1.
Radiologe ; 56(9): 819-24, 2016 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-27495785

RESUMO

In times of RIS (radiology information system) and KIS (hospital information system) systems, patient-related data are at the radiologist's disposal at the push of a button. However, this is not the case for other important data. The increasing complexity of modern medicine demands that up-to-date information like protocols, SOPs (Standards of Practice), news and modifications are constantly accessible to all employees. This aspect of quality assurance becomes increasingly important in the context of certification. For such knowledge management purposes we have built a wiki in our department. Here we report our positive experiences with this technology.


Assuntos
Sistemas de Informação Hospitalar/organização & administração , Disseminação de Informação/métodos , Gestão do Conhecimento , Modelos Organizacionais , Serviço Hospitalar de Radiologia/organização & administração , Mídias Sociais/organização & administração , Alemanha , Conhecimentos, Atitudes e Prática em Saúde
2.
Internist (Berl) ; 52(10): 1191-202; quiz 1203, 2011 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-21912903

RESUMO

The application of imaging methods in patients that are highly dependent on medical support is limited. Ultrasound has a prominent impact due to its flexibility, bedside availability, rapid results, and cost-effectiveness - especially in the assessment of cardiovascular and abdominal diseases. Ultrasound artifacts at the pleura-air interface play an emerging role in the diagnosis of thoracic disease. X-ray imaging is increasingly limited to the assessment of medical artifacts and the follow-up of pulmonary disorders. Daily routine chest X-rays should be abandoned. Multidetector computed tomography has evolved as the gold standard in the definitive diagnosis of many acute critical disorders despite the need for patient transportation. The application of magnetic resonance tomography is in contrast restricted to specific central nervous system diseases.


Assuntos
Cuidados Críticos/métodos , Estado Terminal , Diagnóstico por Imagem/métodos , Artefatos , Diagnóstico por Imagem/efeitos adversos , Humanos , Enteropatias/diagnóstico , Imageamento por Ressonância Magnética/efeitos adversos , Imageamento por Ressonância Magnética/métodos , Tomografia Computadorizada Multidetectores/efeitos adversos , Tomografia Computadorizada Multidetectores/métodos , Sensibilidade e Especificidade , Doenças Torácicas/diagnóstico , Ultrassonografia/métodos
3.
Rofo ; 179(8): 796-803, 2007 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-17638172

RESUMO

Molecular imaging of small animals has made considerable progress in the last years. Various research fields are interested in imaging small animals due to the lower numbers of animals per experiment. This has advantages with respect to financial, ethical and research aspects. Non-invasive imaging allows examination of one animal several times during the same experiment. This makes it possible to follow a pathological process in the same animal over time. However, the radiological methods used such as magnetic resonance imaging or computed tomography as well as the nuclear medicine methods such as single photon emission computed tomography or positron emission tomography suffer from disadvantages. Molecular aspects are limited in the radiological methods while anatomical localization is difficult in nuclear medicine. The fusion of these methods leads to additional information. This review shows today's possibilities with their advantages as well as disadvantages.


Assuntos
Diagnóstico por Imagem/tendências , Diagnóstico por Imagem/veterinária , Previsões , Aumento da Imagem/métodos , Medicina Nuclear/tendências , Radiologia/tendências , Técnica de Subtração/tendências , Animais
4.
Rofo ; 179(8): 811-7, 2007 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-17638175

RESUMO

PURPOSE: To evaluate the technical success rate, procedure-related complications, and clinical long-term results for patients who underwent infrapopliteal angioplasty. MATERIALS AND METHODS: We retrospectively evaluated all patients who underwent infrapopliteal angioplasty to treat critical chronic limb ischemia or severe claudication from 1/1997 to 12/1999. We excluded patients with acute (< 2 weeks) limb ischemia. Procedure-related data were prospectively documented in a database and analyzed with a focus on the technical success rate and procedure-related complications. In addition all clinical documents were analyzed, and a follow-up examination was performed or telephone interviews were conducted with patients, relatives and referring doctors for follow-up. The primary end points were the limb salvage rate and patient survival rate. The secondary end points included the complication rate, technical success rate, and walking distance. RESULTS: 112 patients with a mean age of 72 years (41 women, 71 men) underwent crural angioplasty on 121 limbs. Four patients suffered from severe claudication (Rutherford category 3) and all others had critical chronic limb ischemia (category 4 to 6). The complication rate was 2.7 %. The technical success rate was 92 %. The ankle brachial index increased from 0.59 to 0.88. The mean walking distance increased significantly from 52 +/- 66 to 284 +/- 346 meters at the time of follow-up. The limb salvage rate was 83.6 % after one year and 81.1 % after three years. The mean survival rate according to Kaplan-Meier was 79.4 %, 69.2 %, and 54.2 % at 1, 2, and 3 years, respectively. Patients with at least one patent run-off vessel after angioplasty had a significantly better limb salvage rate. Diabetes was not a risk factor for limb salvage. CONCLUSION: Infrapopliteal angioplasty shows a high technical success rate with an acceptable complication rate. The clinical long-term success seems favorable if a least one open run-off vessel was able to be achieved. However, the survival rate was limited by the co-morbidity in this patient group.


Assuntos
Angioplastia com Balão/mortalidade , Isquemia/mortalidade , Isquemia/cirurgia , Perna (Membro)/irrigação sanguínea , Perna (Membro)/cirurgia , Medição de Risco/métodos , Idoso , Feminino , Alemanha/epidemiologia , Humanos , Isquemia/diagnóstico por imagem , Perna (Membro)/diagnóstico por imagem , Estudos Longitudinais , Masculino , Prevalência , Prognóstico , Radiografia , Estudos Retrospectivos , Fatores de Risco , Análise de Sobrevida , Taxa de Sobrevida , Resultado do Tratamento
5.
Rofo ; 177(3): 321-5, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15719292

RESUMO

PURPOSE: To evaluate the feasibility of aortic stentgraft micromovement detection using digital roentgen stereophotogrammetric analysis on plane film radiographs. MATERIAL AND METHODS: An aortic stentgraft used for demonstration purposes was marked with 10 tantalum markers of 0.8 mm in diameter. The stentgraft was placed on a Plexiglas phantom with 5 tantalum markers of 1 mm in diameter simulating a fixed segment needed for mathematical analysis. In a subsequent step, the stentgraft was placed onto an orthopaedic spine model to simulate in vivo conditions.in a next step. Two radiographs taken simultaneously from different angles were used for simulating different stentgraft movement, e. g. translation, angulation, aortic pulsation and migration in the spine model. Movement of the stentgraft markers was analysed using a commercially available digital RSA setup (UmRSA(R) 4.1, RSA Biomedical, Umea, Sweden). RESULTS: Our study shows the feasibility of measuring aortic stentgraft movement and changes in stentgraft shape in the submillimeter range using digital roentgen stereophotogrammetric analysis. Translation along the 3 cardinal axes, change in stentgraft shape, simulation of aortic pulsation and simulation of in vivo conditions could be described precisely. CONCLUSION: Aortic stentgraft movement detection using digital roentgen stereophotogrammetric analysis on plane film radiographs is a very promising, precise method.


Assuntos
Aorta , Processamento de Imagem Assistida por Computador , Fotogrametria , Falha de Prótese , Radiografia/métodos , Stents , Aneurisma da Aorta Abdominal/cirurgia , Estudos de Viabilidade , Humanos , Imagens de Fantasmas , Fotogrametria/métodos , Polimetil Metacrilato , Tantálio
6.
Invest Radiol ; 36(5): 257-65, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11323513

RESUMO

RATIONALE AND OBJECTIVES: To evaluate the feasibility and safety of using gadolinium chelates for x-ray digital subtraction angiography (DSA) in patients with contraindications to iodinated contrast material. METHODS: We performed 30 DSAs in 22 patients (5 females, 17 males; mean age 64.9 years) with contraindications to iodinated contrast media (renal insufficiency: n = 28; hyperthyroidism: n = 1; contrast allergy: n = 2). Gadolinium chelates were administered as 0.5 mol/L solutions (mean volume of gadolinium chelates per patient was 34 +/- 19 mL). Gadolinium chelates were the sole contrast agent in 17 examinations, were used in conjunction with carbon dioxide (CO2) in 8 studies, (mean 212 +/- 226 mL), and were combined with the restricted use of nonionic iodinated contrast (mean 12.8 +/- 4.7 mL) in 6 examinations. We carried out 15 diagnostic angiographies and 15 percutaneous transluminal angioplasties. RESULTS: Use of gadolinium chelates allowed us to obtain diagnostic angiographic images in all cases. However, the quality of angiograms was inferior compared with that obtained with iodinated contrast agents and superior compared with CO2 as the contrast material. Adverse events were not noted. Mean serum creatinine was 2.6 +/- 1.5 mg/dL before and 2.3 +/- 1.0 mg/dL after DSA. No patient developed contrast-induced nephropathy. CONCLUSIONS: Gadolinium chelates produce an x-ray DSA intermediate in image quality between iodinated contrast and CO2. Digital subtraction angiography with intra-arterial gadolinium chelate administration may offer an alternative to iodinated contrast material in patients with contraindications to iodine.


Assuntos
Angiografia Digital/métodos , Quelantes , Meios de Contraste , Gadolínio DTPA , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
7.
Invest Radiol ; 38(4): 193-9, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12649642

RESUMO

RATIONALE AND OBJECTIVES: To evaluate prospectively the efficacy of gadobutrol as contrast agent for computed tomography (CT) compared with iodinated contrast media in a porcine animal model. METHODS: In 8 domestic pigs (35 +/- 4 kg body weight [BW]), continuous spiral CTs of the chest and abdomen were performed using either 2 mmol/kg BW Gadovist 1.0 (1 mol/L gadobutrol) intravenously or Ultravist (300 mg I/mL iopromide) (slice 5 mm, table feed 7.5 mm, reconstruction increment 5 mm). One week later, the same animals were examined using the same protocol with the other contrast agent. In 2 additional animals, serial CTs were performed at the same level using gadobutrol or iopromide on day 1 and the alternate agent on day 8 inches order to determine contrast media kinetics, peak enhancement, and time enhancement-product in important vascular regions and parenchymal organs (abdominal aorta, inferior vena cava, liver, and renal parenchyma). Peak enhancement (net increase compared with nonenhanced baseline values) was measured in Hounsfield units (HU) in defined regions of interest. RESULTS: In vivo, the mean peak enhancement 5, 15, 30, and 120 seconds in the abdominal aorta after injection of 2 mL/kg BW gadobutrol and iopromide was 200 +/- 11, 224 +/- 10, 261 +/- 13, and 95 +/- 9 HU versus 232 +/- 10, 298 +/- 10, 152 +/- 11, and 123 +/- 10 HU, respectively. Differences in enhancement of vascular structures was statistically significant (P < 0.05) in carotid arteries (235 +/- 20 HU for gadobutrol and 264 +/- 19 HU for iopromide) and the aortic arch (261 +/- 14 HU for gadobutrol and 279 HU +/- 13 HU for iopromide). No statistical significance was seen in all other measured vascular structures and parenchymal organs. CONCLUSION: Contrast-enhanced CT with 1 mol/L gadobutrol in a dose of 2 mmol/kg BW resulted in an excellent vascular and parenchymal enhancement in most vascular regions and parenchymal organs similar to an equivalent volume of 300 mg/mL iodinated contrast media.


Assuntos
Meios de Contraste , Iohexol/análogos & derivados , Compostos Organometálicos , Tomografia Computadorizada por Raios X , Animais , Gadolínio , Aumento da Imagem , Masculino , Suínos
8.
Magn Reson Imaging ; 18(8): 985-9, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11121702

RESUMO

Visualization of the vessel wall after transluminal angioplasty is important to monitor the restenosis progress. Intravascular ultrasound proved its capabilities as an invasive procedure in many studies. The aim of this study was to evaluate the feasibility of high-resolution MRI as a non-invasive tool for follow-up after PTA. High-resolution magnetic resonance images (pixel size: 0.49 * 0.49 mm(2)) were acquired on a 1.0 T clinical scanner. Morphometry was conducted after conversion of DICOM images into TIFF format using ScionImage on a PC. In-vitro studies using a polyvinylchloride tube were evaluated by two independent investigators. Goldstandard was a caliper rule and direct radiography. Five patients were monitored before and 24 h, six weeks, three months and six months after PTA. In vivo measurements promised a good concordance for both investigators for area as well as for diameter measurements. Area measurements showed correlations up to r = 0.86 (p < 0.001) whereas the correlations of diameters were slightly inferior (r between 0.58 and 0.84; p < 0.005). Relocation of the same slice position in the follow up studies could be guaranteed using anatomic landmarks in the images. As a non-invasive tool to assess restenosis after PTA high-resolution MRI promises to be a reproducible technique. It is easy to identify the same vascular region in different studies due to neighboring anatomic landmarks. Progression of disease as well as success of pharmacologic treatment to prevent restenosis may be monitored.


Assuntos
Angioplastia com Balão , Artérias/anatomia & histologia , Imageamento por Ressonância Magnética , Idoso , Artérias/patologia , Arteriosclerose/terapia , Constrição Patológica , Interpretação Estatística de Dados , Seguimentos , Humanos , Imageamento por Ressonância Magnética/instrumentação , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Recidiva , Software , Fatores de Tempo
9.
Rofo ; 159(5): 466-70, 1993 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-8219142

RESUMO

Intra-arterial local fibrinolysis was performed in 72 patients (51 men, 21 women, mean age 66.8 years) during the course of 78 angioplasties. 11.1% were stage IIa (Fontaine), 38.9% were stage II b, 27.8% were stage III and 22.2% were stage IV. The methods used were conventional fibrinolysis (15.4%), spray lysis (47.4%) and mechanically accelerated fibrinolysis (37.2%). In 66.7% the urokinase dose was < 600,000 I.U., in 17.9% it was > 1,000,000 I.U. Additional balloon dilatation was performed in 72 cases, percutaneous aspiration of thrombo-embolic material in 41 cases and stent implantation in 7 cases. Angiographically the procedure was successful in 90.7%; the Doppler index rose from 0.47 +/- 0.27 to 0.85 +/- 0.3 (p < 0.001). At discharge, staging was: I = 38.9%, IIa = 38.9%, IIb = 5.6%, III = 1.4%, IV = 15.3%. There were no systemic bleeding complications. In 5.1%, complications had to be treated surgically.


Assuntos
Angioplastia com Balão/métodos , Fibrinolíticos/administração & dosagem , Terapia Trombolítica/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Angioplastia com Balão/efeitos adversos , Angioplastia com Balão/estatística & dados numéricos , Quimioterapia Combinada , Estudos de Avaliação como Assunto , Feminino , Humanos , Bombas de Infusão , Infusões Intra-Arteriais/estatística & dados numéricos , Injeções Intra-Arteriais/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Terapia Trombolítica/efeitos adversos , Terapia Trombolítica/instrumentação , Terapia Trombolítica/estatística & dados numéricos
10.
Rofo ; 159(5): 461-6, 1993 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-8219141

RESUMO

A prospective, randomised and double blind comparative study of Midazolam/Tramadol or placebo/Tramadol for premedication before PTA was carried out on 40 patients (12 female and 28 male, average age 66.1 +/- 12). The anxiolytic, analgesic and general findings were quantified by means of a visual analogue score. Pre- and peri-interventional blood gas, blood pressure and pulse rates were determined. The complications of the two schemes were compared. 19 patients received Midazolam/Tramadol and 21 placebo/Tramadol. Patient anxiety was reduced significantly from 25.8 +/- 25 to 4.3 +/- 6 by premedication. Significant increase in the pain score during PTA was observed only in the placebo group (4.3 +/- 12.6 to 27.4 +/- 20.9). There was no difference in the incidence of complications and respiratory depression due to the Midazolam/Tramadol combination was not observed.


Assuntos
Angioplastia com Balão , Midazolam/uso terapêutico , Pré-Medicação , Tramadol/uso terapêutico , Idoso , Angioplastia com Balão/estatística & dados numéricos , Gasometria , Distribuição de Qui-Quadrado , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Humanos , Masculino , Midazolam/efeitos adversos , Pessoa de Meia-Idade , Placebos , Pré-Medicação/estatística & dados numéricos , Radiografia Intervencionista , Tramadol/efeitos adversos
11.
Rofo ; 173(5): 391-8, 2001 May.
Artigo em Alemão | MEDLINE | ID: mdl-11414145

RESUMO

The most important strategies for molecular imaging are presented. Processes can now be imaged in vitro and in vivo at the molecular level with the help of modern procedures such as SPECT, PET, MRI, and highly developed optical methods. The ability to view the expression of genes, the pharmacokinetics of gene therapy vectors, of therapeutic DNA, and of classical pharmacons in vivo opens up completely new perspectives for the research on, diagnosis of, and therapy for diseases. The current status of these developments are described, potential fields of use and possibilities for further development are outlined.


Assuntos
Diagnóstico por Imagem , Expressão Gênica/fisiologia , Terapia Genética , Biologia Molecular , Genes Reporter/genética , Humanos , Imageamento por Ressonância Magnética , Tomografia Computadorizada de Emissão , Tomografia Computadorizada de Emissão de Fóton Único
12.
Rofo ; 172(12): 949-56, 2000 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-11199436

RESUMO

The term molecular radiology intermediate region between radiological imaging and interventional radiology on the one side and molecular biology on the other. In the field of imaging methods are currently being developed by which molecular processes, i.e., gene expression and protein function, can be visualized in vivo. These techniques open new perspectives for research and clinical diagnosis and will be presented in the second part of this review. The present part provides a survey of current developments in gene therapy from a radiological point of view and highlights the part that our specialty may play in this field.


Assuntos
Terapia Genética , Radiografia , Animais , Terapia Genética/métodos , Humanos , Neoplasias/terapia , Doenças Vasculares/terapia
13.
Rofo ; 157(5): 477-83, 1992 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-1421189

RESUMO

The success rate and time taken for recanalization was determined in a prospective study of 82 consecutive unselected patients (53 men, 29 women; mean age 65.7 +/- 13, from 28 to 88 years). There were 106 complete occlusions of infrarenal arteries and a hydrophilic guide wire with a special 5-F recanalization catheter was used. Mean occlusion length was 12.97 +/- 10 cm (from 1 cm-45 cm). 79.3% of occlusions were in the femoro-popliteal territory, 6.6% were iliac and 14.1% tibial. 101 of the 106 occlusions were recanalized (95.3%). Mean recanalization time was 120.8 +/- 228.1 s (from 1 s-1440 s), mean recanalization velocity was 0.11 cm/s. The majority of obstructions could be recanalized in less than one minute. The five occlusions which could not be recanalized were distal lesions in the superficial femoral artery and which were longer than 10 cm; two were calcified. There were no complications resulting from the recanalization apart from three perforations which were clinically not apparent. Consequent angioplasty proved successful in 78.1% of these patients.


Assuntos
Angioplastia com Balão/instrumentação , Arteriopatias Oclusivas/terapia , Artéria Femoral , Artéria Ilíaca , Artéria Poplítea , Artérias da Tíbia , Adulto , Idoso , Idoso de 80 Anos ou mais , Ligas , Angioplastia com Balão/métodos , Angioplastia com Balão/estatística & dados numéricos , Arteriopatias Oclusivas/diagnóstico por imagem , Arteriopatias Oclusivas/epidemiologia , Feminino , Artéria Femoral/diagnóstico por imagem , Humanos , Artéria Ilíaca/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Artéria Poplítea/diagnóstico por imagem , Estudos Prospectivos , Radiografia Intervencionista , Artérias da Tíbia/diagnóstico por imagem , Fatores de Tempo
14.
Rofo ; 175(8): 1125-9, 2003 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-12886483

RESUMO

PURPOSE: To analyze outcome and predictive factors for patient survival and patency rates of unresectable malignant biliary obstruction treated with percutaneous transhepatic insertion of metal stents. MATERIALS AND METHODS: This is a retroslective analysis of 130 patients treated in one interventional radiological center with data collected from patient records and by telephone interviews. The procedure-related data had been prospectively documented in a computer data base. The Kaplan-Meier analysis was performed for univariate and multivariate comparison of survival and patency rates with the log-rank test used for different tumor types. Predictive factors for survival and 30-day mortality were analyzed by a stepwise logistic regression. RESULTS: Underlying causes of malignant biliary obstructions were cholangiocarcinoma in 50, pancreatic carcinoma in 29, liver metastases in 27, gallbladder carcinoma in 20, and other tumors in 4 patients. The technical success rate was 99 %, the complication rate 27 % and the 30-day mortality 11 %. Primary patency rates (406 days with a median of 207 days) did not differ significantly for different tumor types. The survival rates were significantly (p = 0.03 by log-rank test) better for patients with cholangiocarcinoma than for patients with pancreatic carcinoma and liver metastases. Multiple regression analysis revealed no predictive factor for patient survival and 30-day mortality. CONCLUSION: Percutaneous transhepatic insertion of metal biliary endoprostheses offers a good initial and long-term relief of jaundice caused by malignant biliary obstruction. Although survival rates for patients with cholangiocarcinoma are better than for other causes of malignant biliary obstruction, a clear predictive factor is lacking for patients undergoing palliative biliary stent insertion.


Assuntos
Neoplasias dos Ductos Biliares/terapia , Colangiografia , Colestase/terapia , Stents , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias dos Ductos Biliares/diagnóstico por imagem , Neoplasias dos Ductos Biliares/mortalidade , Neoplasias dos Ductos Biliares/secundário , Colestase/diagnóstico por imagem , Colestase/mortalidade , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Cuidados Paliativos , Recidiva , Estudos Retrospectivos , Análise de Sobrevida
15.
Rofo ; 174(11): 1375-9, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12424663

RESUMO

PURPOSE: To evaluate whether RDC and 3DC help clarifying anatomic details in biliary duct disease and is useful for guidance of drainage procedures. MATERIALS AND METHODS: RDC was conducted in 11 consecutive patients (8 male, 3 female, mean age 63 years). Nine patients underwent PTBD for malignant biliary duct stenosis, one patient because of ischemic stenosis after hepaticojejunostomy and one patient presented with an infected biloma. Images were obtained after initial bile duct puncture during single breath hold from 120 projection angles using a rotating C-arm. These images were immediately available and evaluated in order to facilitate the definitive drainage procedure. For additional 3D reconstruction, data were sent to a dedicated workstation and judged by a blinded observer. RESULTS: The availability of a rotating data set of images was judged to be helpful in three patients with complex anatomical situations. Additionally, RDC holds the potential to reduce fluoroscopy time. 3DC allowed analysis of the hepatic bifurcation from different viewing angles in 10 cases with high spatial resolution (mean voxel size 480 micro micro m 3). This may allow a better classification of hilar obstructions according to our preliminary observations. CONCLUSION: Images from RDC and 3DC are helpful in guiding PTBD procedures and for better diagnosis in selected patients with hilar biliary duct stenoses.


Assuntos
Doenças dos Ductos Biliares/diagnóstico por imagem , Colangiografia/métodos , Drenagem , Processamento de Imagem Assistida por Computador , Imageamento Tridimensional , Adulto , Idoso , Doenças dos Ductos Biliares/cirurgia , Ductos Biliares/patologia , Constrição Patológica , Interpretação Estatística de Dados , Feminino , Fluoroscopia , Humanos , Masculino , Pessoa de Meia-Idade , Rotação , Fatores de Tempo
16.
Rofo ; 169(2): 115-20, 1998 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-9739359

RESUMO

PURPOSE: CT angiography was performed in 12 patients with insufficient autologous graft situations to evaluate postoperative patency and situation of the proximal, distal and coronary artery anastomoses of synthetic Perma-Flow coronary artery bypass grafts. METHODS: Bypass grafts were evaluated postoperatively with spiral CT of the mediastinum. At a flow rate of 3 ml/s, 120 ml of contrast material were applied over a cubital vein. Slice thickness was 3 mm, maximum pitch factor 2 and image reconstruction was performed at 2 mm increment. Shaded surface displays were analysed together with axial scans for bypass evaluation. RESULTS: 8 out of 12 synthetic bypasses proved to be patent. One bypass was completely occluded and in three patients the distal portions of the grafts were occluded. Coronary angiography performed in one case confirmed complete bypass occlusion. Due to the occlusions, 8 distal and 12 proximal anastomoses were visible. Only 8 out of 19 side-to-side coronary artery anastomoses could be sufficiently well imaged with this technique. CONCLUSIONS: CT angiography is suitable for postoperative screening of synthetic coronary bypasses to determine the patency and anastomotic situations. Coronary artery anastomoses however are not sufficiently imaged and coronary angiography continues to be required.


Assuntos
Implante de Prótese Vascular , Angiografia Coronária/métodos , Ponte de Artéria Coronária , Oclusão de Enxerto Vascular/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Anastomose Cirúrgica/métodos , Prótese Vascular , Vasos Coronários/cirurgia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Grau de Desobstrução Vascular
17.
Rofo ; 176(10): 1501-5, 2004 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-15383985

RESUMO

BACKGROUND: Pulmonary arteriovenous malformations (PAVM) can be found in approximately 20 % to 35 % of patients with hereditary hemorrhagic telangiectasia (HHT). PAVM should be treated since they are a source of paradoxical embolization, potentially resulting in severe neurologic complications. The treatment of choice is the endovascular embolization with coils. PATIENTS AND METHODS: Seven patients with HHT underwent superselective embolization of PAVM detected during screening for PAVM. Four patients had a single PAVM and one patient 3, 4 and 5 PAVMs, respectively. Electrolytically detachable coils were used for embolization. In addition, coils with synthetic fibers were used during 6 embolizations for completion of embolization. RESULTS: Embolization was technically successful in all patients. Complete primary occlusion was achieved in all PAVM. No coil migration or occlusion of unaffected pulmonary arteries was observed. After embolization, one patient developed a small pleural effusion, which was treated symptomatically. CONCLUSION: As a minimally invasive procedure, superselective embolization is the treatment of choice in treating PAVM in patients with HHT. With the use of electrolytically detachable coils, the ideal coil size can be chosen and exact placement achieved without the risk of coil migration or occlusion of unaffected pulmonary arteries.


Assuntos
Malformações Arteriovenosas/terapia , Embolização Terapêutica/instrumentação , Artéria Pulmonar/anormalidades , Veias Pulmonares/anormalidades , Telangiectasia Hemorrágica Hereditária/terapia , Adolescente , Adulto , Idoso , Angiografia , Malformações Arteriovenosas/diagnóstico , Malformações Arteriovenosas/diagnóstico por imagem , Embolização Terapêutica/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Radiografia Torácica , Tomografia Computadorizada Espiral , Tomografia Computadorizada por Raios X
18.
Rofo ; 176(9): 1226-31, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15346255

RESUMO

PURPOSE: To implement a software platform (DynaVision) dedicated to analyze data from functional imaging of tumors with different mathematical approaches, and to test the software platform in pancreatic carcinoma xenografts in mice with severe combined immunodeficiency disease (SCID). MATERIALS AND METHODS: A software program was developed for extraction and visualization of tissue perfusion parameters from dynamic contrast-enhanced images. This includes regional parameter calculation from enhancement curves, parametric images (e. g., blood flow), animation, 3D visualization, two-compartment modeling, a mode for comparing different datasets (e. g., therapy monitoring), and motion correction. We analyzed xenograft tumors from two pancreatic carcinoma cell lines (BxPC3 and ASPC1) implanted in 14 SCID mice after injection of Gd-DTPA into the tail vein. These data were correlated with histopathological findings. RESULTS: Image analysis was completed in approximately 15 minutes per data set. The possibility of drawing and editing ROIs within the whole data set makes it easy to obtain quantitative data from the intensity-time curves. In one animal, motion artifacts reduced the image quality to a greater extent but data analysis was still possible after motion correction. Dynamic MRI of mice tumor models revealed a highly heterogeneous distribution of the contrast-enhancement curves and derived parameters, which correlated with differences in histopathology. ASPC1 tumors showed a more hypervascular type of curves with faster and higher signal enhancement rate (wash-in) and a faster signal decrease (wash-out). BXPC3 tumors showed a more hypovascular type with slower wash-in and wash-out. This correlated with the biological properties of the tumors. CONCLUSION: With the described software, it was possible to analyze tissue perfusion parameters in small xenograft tumor models in mice. Our data correlated with histopathological data, and the qualitative and quantitative perfusion parameters could distinguish two tumor entities with different growth characteristics.


Assuntos
Imageamento Tridimensional , Imageamento por Ressonância Magnética , Neoplasias Pancreáticas/diagnóstico , Software , Animais , Artefatos , Linhagem Celular Tumoral , Meios de Contraste , Modelos Animais de Doenças , Gadolínio DTPA , Técnicas Histológicas , Aumento da Imagem , Camundongos , Camundongos SCID , Modelos Teóricos , Neoplasias Pancreáticas/irrigação sanguínea , Neoplasias Pancreáticas/patologia , Perfusão , Transplante Heterólogo
19.
Exp Toxicol Pathol ; 56(1-2): 25-35, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15581272

RESUMO

In neurooncology transplanting, tumors can be used for many purposes e.g. to solve questions concerning the etiology and pathogenesis of such tumors or their management. Experimentally induced and transplanted tumors of the nervous system become reproducible in their morphology and growth parameters after about 12 subsequent intracerebral passages. During the period from the first to the 12th intracerebral generations, a simplification of the histology and a reduction of the induction times take place. Nowadays the growth behavior of such tumors can be followed by imaging methods such as MRI if specially adapted to small animals. Our results are based on the investigation of over 2350 experimentally induced tumors of the central and peripheral nervous system that were diagnosed according to the rules of human and rodent brain tumor classification and various subgroups of this sample, analyzed by electron microscopy, postmortal angiography and MRI.


Assuntos
Neoplasias Encefálicas/patologia , Animais , Neoplasias Encefálicas/irrigação sanguínea , Neoplasias Encefálicas/induzido quimicamente , Etilnitrosoureia , Feminino , Imageamento por Ressonância Magnética , Transplante de Neoplasias , Ratos
20.
Vasa ; 29(2): 99-102, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10901085

RESUMO

BACKGROUND: The purpose of this study was to evaluate the effect of nitric oxide (NO) on basic fibroblast growth factor (bFGF)-stimulated migration of bovine VSMC in vitro. METHODS: For the migration assay 50,000 cells from passages 4 to 8 were put into a migration chamber and stimulated with 10 ng bFGF/ml (control group). For another experiment, the NO donator sodium nitroprusside (SNP) (10(-6), 10(-8), 10(-10) M), the second messenger of NO 8-bromo-cGMP (10(-6), 10(-8), 10(-10) M) and 100 U of superoxide dismutase (SOD) were added. Migration of cells was quantified after fixing and staining of the cells by means of light microscopy. RESULTS: Cell migration was significantly inhibited by SNP in a dose dependent manner (p < 0.01 with t-test). This effect was mirrored by 8-bromo-cGMP and not significantly inhibited by SOD, confirming this to be an NO mediated effect and excluding side-effects of superoxide-derived oxidation products. CONCLUSION: Nitric oxide inhibits the basic fibroblast growth factor stimulated migration of bovine vascular smooth muscle cells in vitro.


Assuntos
Movimento Celular/efeitos dos fármacos , Fator 2 de Crescimento de Fibroblastos/antagonistas & inibidores , Músculo Liso Vascular/citologia , Óxido Nítrico/farmacologia , Animais , Bovinos , Relação Dose-Resposta a Droga , Fator 2 de Crescimento de Fibroblastos/farmacologia , Técnicas In Vitro
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