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1.
Radiologe ; 60(8): 737-746, 2020 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-32350555

RESUMO

PURPOSE: Interdisciplinary tumor boards are periodical conferences, where optimal individual therapy plans are developed among medical experts with different specializations. The presence of a board-certified radiologist is medically indispensable in almost all relevant boards. In order to systematically evaluate the current workload for radiologists caused by these boards, we evaluated the current situation within German radiology to obtain numbers for future personnel planning. MATERIALS AND METHODS: We performed an online survey. We invited all 33 German university chairmen and 50 randomly selected head physicians of radiology at level 3 hospitals to participate. RESULTS: We had a participation rate of 79% (26/33) at university hospitals and 56% (28/50) at of level 3 non-university hospitals. The average total number of tumor boards was 3.3/day or 16.7/week at university hospitals and 2.6/day or 13/week at level 3 non-university hospitals. We calculated an average time considering preparation and execution as well as the average number of boards of 33.1 h/week for university hospitals and 18.2 h/week for level 3 hospitals. This results in a 78.8% workload for a board-certified radiologist at a university hospital (regular weekly work time 42 h) and 45.5% work load for level 3 hospitals (regular weekly work time 40 h). CONCLUSION: "Speaking radiology" as in interdisciplinary tumor boards represents a fundamental matter of course in radiology. The active participation in boards accomplished by radiologists improves evidence-based patient care. However, given the prevailing scarcity of resources in medicine, the data collected here regarding personnel costs for clinical radiology for participation in tumor boards must be taken into account in future discussions on personnel compensation.


Assuntos
Neoplasias/diagnóstico por imagem , Radiologia/organização & administração , Alemanha , Conselho Diretor/organização & administração , Humanos , Internet , Inquéritos e Questionários
2.
Radiologe ; 58(1): 56-59, 2018 Jan.
Artigo em Alemão | MEDLINE | ID: mdl-29222586

RESUMO

BACKGROUND: Sclerosing mesenteritis (SM) and mesenteric panniculitis are rare processes of the mesentery which pose a major clinical and imaging challenge. This review article attempts to introduce a systematic nomenclature to address typical symptoms, imaging and major differential diagnoses. RESULTS: SM with its subtypes-mesenteric lipodystrophy, panniculitis and retractile mesenteritis-is a chronic process with a very diverse and heterogeneous clinical appearance. The typical radiological characteristics ("misty mesentery", increased lymph nodes, pseudocapsule and "fat halo") are also not very specific. A link between SM and malignant diseases is not proven, but there is controversial discussion. Therefore, if there are doubts about the diagnosis, further examinations and a biopsy are desired. CONCLUSION: When diagnosing SM, "red flags", i. e. characteristics that are atypical for SM in imaging, should be considered. In case of ambiguous imaging, differential diagnostics should also consider malignant diseases and exclude them.


Assuntos
Paniculite Peritoneal , Biópsia , Diagnóstico Diferencial , Humanos , Mesentério , Radiografia
3.
Radiologe ; 54(5): 436-48, 2014 May.
Artigo em Alemão | MEDLINE | ID: mdl-24824378

RESUMO

The increasing availability of computed tomography has meant that the number of incidentally detected solitary pulmonary nodules (SPN) has greatly increased in recent years. A reasonable management of these SPN is necessary in order to firstly be able to detect malignant lesions early on and secondly to avoid upsetting the patient unnecessarily or carrying out further stressful diagnostic procedures. This review article shows how the dignity of SPNs can be estimated and based on this how the management can be accomplished taking established guidelines into consideration.


Assuntos
Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/terapia , Guias de Prática Clínica como Assunto , Radiografia Torácica/normas , Nódulo Pulmonar Solitário/diagnóstico por imagem , Nódulo Pulmonar Solitário/terapia , Tomografia Computadorizada por Raios X/normas , Detecção Precoce de Câncer/normas , Humanos , Prognóstico , Intensificação de Imagem Radiográfica/normas , Resultado do Tratamento
4.
Hum Mol Genet ; 18(11): 1909-23, 2009 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-19279158

RESUMO

Mutations in CHD7, a chromodomain gene, are present in a majority of individuals with CHARGE syndrome, a multiple anomaly disorder characterized by ocular Coloboma, Heart defects, Atresia of the choanae, Retarded growth and development, Genital hypoplasia and Ear anomalies. The clinical features of CHARGE syndrome are highly variable and incompletely penetrant. Olfactory dysfunction is a common feature in CHARGE syndrome and has been potentially linked to primary olfactory bulb defects, but no data confirming this mechanistic link have been reported. On the basis of these observations, we hypothesized that loss of Chd7 disrupts mammalian olfactory tissue development and function. We found severe defects in olfaction in individuals with CHD7 mutations and CHARGE, and loss of odor evoked electro-olfactogram responses in Chd7 deficient mice, suggesting reduced olfaction is due to a dysfunctional olfactory epithelium. Chd7 expression was high in basal olfactory epithelial neural stem cells and down-regulated in mature olfactory sensory neurons. We observed smaller olfactory bulbs, reduced olfactory sensory neurons, and disorganized epithelial ultrastructure in Chd7 mutant mice, despite apparently normal functional cilia and sustentacular cells. Significant reductions in the proliferation of neural stem cells and regeneration of olfactory sensory neurons in the mature Chd7(Gt/+) olfactory epithelium indicate critical roles for Chd7 in regulating neurogenesis. These studies provide evidence that mammalian olfactory dysfunction due to Chd7 haploinsufficiency is linked to primary defects in olfactory neural stem cell proliferation and may influence olfactory bulb development.


Assuntos
Anormalidades Múltiplas/fisiopatologia , Proliferação de Células , DNA Helicases/genética , Proteínas de Ligação a DNA/genética , Transtornos do Olfato/fisiopatologia , Células Receptoras Sensoriais/citologia , Células-Tronco/citologia , Anormalidades Múltiplas/genética , Anormalidades Múltiplas/metabolismo , Animais , Criança , DNA Helicases/metabolismo , Proteínas de Ligação a DNA/metabolismo , Modelos Animais de Doenças , Feminino , Expressão Gênica , Humanos , Masculino , Camundongos , Camundongos Knockout , Mutação , Transtornos do Olfato/genética , Transtornos do Olfato/metabolismo , Mucosa Olfatória/citologia , Mucosa Olfatória/crescimento & desenvolvimento , Mucosa Olfatória/metabolismo , Células Receptoras Sensoriais/metabolismo , Olfato , Células-Tronco/metabolismo
5.
Crit Rev Toxicol ; 41(4): 321-38, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21438739

RESUMO

The animal testing protocols used today to evaluate the carcinogenicity of chemicals are very different from those used in the earlier part of the 20th century. To explore how cancer bioassays have changed over time, we surveyed the literature discussing test design and interpretation from the 1930s to the present. We also analyzed compendia of bioassays published by the US Public Health Service (US PHS) from 1938 to 1978, and evaluated the data to understand the evolution of testing methodology (e.g., animals used, test duration) and the types of chemicals being studied. The cancer bioassay evolved in several stages. At the beginning of the 20th century, animal bioassays were primarily used to re-create known human diseases, whereas in the 1940s to 1960s, animal bioassays were largely used to evaluate the safety of chemicals in foods, drugs, and cosmetics. Beginning in the late 1960s and 1970s, chemicals primarily associated with occupational or environmental exposures were also evaluated. Testing strategies now emphasize a suite of tests including multiple in vitro tests and both short-term and long-term animal tests. The objectives of testing are broader, too, with test goals encompassing information regarding mode of action and other parameters aimed at evaluating potential species differences (e.g., in toxicokinetics) and their relevance for evaluating human risks. It is important to consider this evolution when evaluating the testing methodology and scientific conclusions in earlier eras. As toxicology continues to develop, testing methods will continue to change in concert with increased knowledge and understanding.


Assuntos
Bioensaio/métodos , Testes de Carcinogenicidade/métodos , Carcinógenos/toxicidade , Poluentes Ambientais/toxicidade , Animais , Animais de Laboratório , Bioensaio/história , Testes de Carcinogenicidade/história , Modelos Animais de Doenças , História do Século XX , História do Século XXI , Humanos , Medição de Risco
6.
J Surg Case Rep ; 2021(2): rjab008, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33604020

RESUMO

Upper gastrointestinal bleeding from esophagogastric varices is a common scenario, especially in patients with portal hypertension induced by liver cirrhosis or other diseases with thrombosis of the splenic vein. However, accessory spleen as pathophysiological cause of a regional, left-sided portal hypertension and consecutive development of isolated gastric varices is rare. We report a case of recurrent gastric variceal bleeding resulting from sinistral portal hypertension associated with an accessory spleen in a patient who had traumatic splenectomy many decades before. The accessory spleen is an extremely rare cause for the development of regional, left-sided portal hypertension leading to isolated gastric varices. Minimally invasive splenectomy is a safe and efficient treatment option.

7.
Clin Hemorheol Microcirc ; 76(2): 143-153, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32925006

RESUMO

AIM: To evaluate the use of dynamic contrast enhanced ultrasound (CEUS) with parametric color-coded imaging and time intensity curve analysis (TIC) for planning and follow-up after prostate arterial embolization (PAE). MATERIAL/METHOD: Before and after selective iliacal embolization by PAE with a follow up of 6 months 18 male patients (43-78 years, mean 63±3.5 years) with histopathological proven benign prostate hyperplasia were examined by one experienced examiner. A multifrequency high resolution probe (1-6 MHz) was used for transabdominal ultrasound and CEUS with bolus injections of 2.4 ml sulphur-hexafluoride microbubbles. Independent evaluation of color-coded parametric imaging before and after PAE by in PACS stored DICOM loops from arterial phase (10-15 s) up to 1min were performed. Criteria for successful treatment were reduction of early arterial enhancement by changes of time to peak (TTP) and area under the curve (AUC) by measurements in 8 regions of interest (ROI) of 5 mm in diameter at the margin and in the center and changes from hyperenhancement in parametric imaging (perfusion evaluation of arterial enhancement over 15 s) from red and yellow to blue and green by partial infarctions. Reference imaging method was the contrast high resolution 3 tesla magnetic resonance tomography (MRI) using 3D vibe sequences before and after PAE and for the follow up after 3 and 6 months. RESULTS: PAE was technically and clinically successful in all 18 patients with less clinical symptoms and reduction of the gland volume. In all cases color-coded CEUS parametric imaging was able to evaluate partial infarction after embolization with changes from red and yellow to green and blue colors in the embolization areas. Relevant changes could be evaluated for TIC-analysis of CEUS with reduced arterial enhancement in the arterial phase and prolonged enhancement of up to 1 min with significant changes (p = 0.0024). The area under the curve (AUC) decreased from 676±255.04 rU (160 rU-1049 rU) before PAE to 370.43±255.19 rU (45 rU-858 rU) after PAE. Time to peak (TTP) did not change significantly (p = 0.6877); TTP before PAE was 25.82±9.04 s (12.3 s-42.5 s) and after PAE 24.43±9.10 s (12-39 s). Prostate volume decreased significantly (p = 0.0045) from 86.93±34.98 ml (30-139 ml) before PAE to 50.57±26.26 ml (19-117 ml) after PAE. There were no major complications and, in most cases (14/18) a volume reduction of the benign prostate hyperplasia occurred. CONCLUSION: Performed by an experienced examiner CEUS with parametric imaging and TIC-analysis is highly useful to further establish prostatic artery embolization (PAE) as a successful minimal invasive treatment of benign prostatic hyperplasia.


Assuntos
Meios de Contraste/uso terapêutico , Embolização Terapêutica/métodos , Hiperplasia Prostática/cirurgia , Ultrassonografia/métodos , Adulto , Idoso , Humanos , Masculino , Pessoa de Meia-Idade , Hiperplasia Prostática/tratamento farmacológico , Resultado do Tratamento
8.
Clin Hemorheol Microcirc ; 73(1): 95-104, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31561349

RESUMO

OBJECTIVE: The use of a standardized dynamic contrast enhanced ultrasound (CEUS) protocol to determine perfusion of hepatocellular carcinomas (HCC) using quantitative analysis. METHODS: Retrospective analysis of 27 patients with hepatocellular carcinoma examined by a standardized protocol (bolus injection of 2.4 ml sulphur hexafluoride microbubbles, arterial phase to portal venous phase using continuous CINE-loops over 1 minute, short CINE-loops after 2, 3, 4, 5 and 6 minutes and additional single images for B-mode, CCDS). The examination was performed by an experienced sonographer with a high resolution, multi-frequency transducer (1-6 MHz). The reading of the reference imaging (contrast enhanced CT and MRI) and histopathology, if necessary, was performed independently. Retrospective analysis of the CEUS DICOM loops was done using time intensity curve analysis (TIC) with evaluation of the time to peak (TTP) and the area under the curve (AUC). RESULTS: All tumor lesions were characterized by CEUS, based on typical contrast patterns for HCC lesions with arterial enhancement and wash out in the late phase, corresponding to MRI with liver specific contrast agent or contrast enhanced CT. Mean TTP (SD) in the tumor centre (C) was 19.93 (11.31), in the periphery (P) 22.94 (9.44) and in the normal liver tissue (LT) 28.19 (11.34) with significant differences between all zones C/P (p = 0.013), C/LT (p = 0.005) and P/LT (p = 0.022). AUC mean (SD) in the tumor centre (C) was 660.03 (292.64), in the periphery (P) 586.04 (237.01) and in the normal liver tissue (LT) 484.20 (236.99), also with significant differences between all zones C/P (p = 0.001), C/LT (p < 0.001) and P/LT (p < 0.001). CONCLUSION: TIC-analysis is an easy-to-use tool for the dynamic evaluation of microvascularization in hepatocellular carcinoma and allows a fast and cost-efficient quantitative analysis.


Assuntos
Carcinoma Hepatocelular/diagnóstico por imagem , Meios de Contraste/uso terapêutico , Neoplasias Hepáticas/diagnóstico por imagem , Microvasos/diagnóstico por imagem , Ultrassonografia/métodos , Idoso , Idoso de 80 Anos ou mais , Carcinoma Hepatocelular/patologia , Estudos de Avaliação como Assunto , Feminino , Humanos , Neoplasias Hepáticas/patologia , Masculino , Microbolhas , Pessoa de Meia-Idade , Estudos Retrospectivos
9.
Clin Hemorheol Microcirc ; 72(1): 85-93, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30584122

RESUMO

PURPOSE: To assess the postprocedure findings after percutaneous irreversible electroporation (IRE) of hepatocellular carcinoma (HCC) in contrast-enhanced ultrasound (CEUS). MATERIALS AND METHODS: Percutaneous IRE was performed in a total of 22 patients with 24 HCC tumours following interdisciplinary tumour board review. The lesions were documented using CEUS before, immediately and within 24 hours after IRE. During follow-up CEUS was performed at 6 weeks and 3, 9, and 12 months after ablation. Two experienced radiologists evaluated the acquired CEUS image date in a consensus reading. RESULTS: Median tumour size before treatment was 13.7±4.8 mm (short axis) and 16.0±5.2 mm (long axis). All HCC lesions showed arterial hyperenhancement in CEUS. Median size of the ablation defect after ablation was 29.3±5.2 mm (short axis) and 31.6±5.6 mm (long axis). After IRE all tumours showed complete devascularization. The size of the ablation defects showed significant shrinkage and reduced peripheral enhancement in the course of follow-up. At 12 months follow-up the ablation defect size decreased to 16.7±4.3 mm (short axis) and 18.3±4.1 mm (long axis). CONCLUSION: CEUS showed a complete devascularization of HCC tumours after IRE. Post-intervetional peripheral enhancement returned to normal during follow-up and may represent zones of reversible damage of cellular integrity through electroporation. A significant shrinkage of the ablation defects during 12 month of follow-up was seen in all cases.


Assuntos
Carcinoma Hepatocelular/diagnóstico por imagem , Meios de Contraste/uso terapêutico , Eletroporação/métodos , Neoplasias Hepáticas/diagnóstico por imagem , Ultrassonografia/métodos , Carcinoma Hepatocelular/patologia , Meios de Contraste/farmacologia , Feminino , Seguimentos , Humanos , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Tempo
10.
Sci Rep ; 9(1): 19876, 2019 12 27.
Artigo em Inglês | MEDLINE | ID: mdl-31882716

RESUMO

The incidence and evolution of venous thrombosis adjacent to the ablation zone after percutaneous irreversible electroporation (IRE) were evaluated to identify potential risk factors in patients with hepatic malignancies. 205 venous structures (in 87 patients) within a ≤1.0 cm radius of the ablation zone were assessed after IRE of 112 hepatic lesions (74 primary, 38 secondary hepatic malignancies) by pre-interventional and post-interventional (1-3 days, 6 weeks and 3 months after IRE) contrast-enhanced magnetic resonance imaging. The relationships between venous thrombosis and clinical features were analysed using a binary logistic regression model. In 27 of 87 patients (31%), a total of 67 venous complications were noted during the 3 months follow-up. Thrombosis represented the most frequently observed complication (n = 47; 70.1%), followed by vessel narrowing (n = 20; 29.9%). 5 (10.6%) of 47 thromboses showed spontaneous regression 3 months after IRE. A small vessel diameter (p = 0.011) and post-interventional vessel narrowing (p = 0.006) were independently associated with delayed post-ablative thrombosis. Delayed venous thrombosis frequently occurs after IRE of hepatic malignancies. Pre-existing vessel narrowing and a small vessel diameter represent significant risk factors that require further surveillance and potentially therapeutic intervention.


Assuntos
Carcinoma Hepatocelular/complicações , Carcinoma Hepatocelular/patologia , Eletroporação , Neoplasias Hepáticas/complicações , Neoplasias Hepáticas/patologia , Trombose Venosa/etiologia , Trombose Venosa/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Incidência , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Trombose Venosa/complicações
11.
Int J Comput Assist Radiol Surg ; 13(12): 1991-1997, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29728899

RESUMO

PURPOSE: To compare CT-navigated stereotactic microwave ablation (SMWA) to non-navigated conventional MWA (CMWA) for percutaneous ablation of liver malignancies. METHODS: A matched pair analysis of 36 patients who underwent MWA of primary or secondary liver malignancies (10 hepatocellular carcinoma and 8 metastases) was conducted. A total of 18 patients undergoing SMWA were included in this prospective study. Patients were matched in terms of tumor size, liver segment and entity to retrospective CMWA procedures. The endpoints were procedure time, accuracy of needle placement, technical success rate, complication rate and dose-length product (DLP). RESULTS: The procedure durations were 23.9 min (SD 3.7) for CMWA and 21.8 min (SD 16.3) for SMWA (p = 0.22). The procedural accuracy for SMWA and CMWA was identical for both groups (3.7 mm). The total DLP was significantly lower for SMWA than for CMWA (2115 mGy cm (SD 276) vs. 3109 mGy cm (SD 1137), respectively; p < 0.01). Complete ablation without residual tumor was observed in 94% (17 of 18) of SMWA and in 83% (15 of 18) of CMWA patients (p = 0.31). No complications occurred. CONCLUSIONS: SMWA is highly accurate and reduces the radiation dose without increasing the procedure time.


Assuntos
Técnicas de Ablação/métodos , Carcinoma Hepatocelular/cirurgia , Imageamento Tridimensional , Neoplasias Hepáticas/cirurgia , Micro-Ondas/uso terapêutico , Técnicas Estereotáxicas , Cirurgia Assistida por Computador/métodos , Carcinoma Hepatocelular/diagnóstico , Feminino , Humanos , Neoplasias Hepáticas/diagnóstico , Masculino , Análise por Pareamento , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do Tratamento
12.
Clin Hemorheol Microcirc ; 69(1-2): 59-67, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29758936

RESUMO

BACKGROUND:  With the rising number of percutaneous ablation therapies in malignant liver lesions there is a need of reliable diagnostics after the intervention to differentiate between reactive changes and tumor. PURPOSE: To assess the success of percutaneous ablation therapies for malignant liver lesions using CEUS with perfusion analysis. MATERIAL AND METHODS: Retrospective analysis of perfusion analysis for 67 patients with 94 malignant liver lesions, treated with ablation therapies. The lesions were 70 hepatocellular carcinomas (HCC), 18 metastases, 4 cholangiocellular carcinomas (CCC), 2 lesions remained unclear. CEUS was performed after bolus injection of 1.6-2.4 ml of sulfur-hexafluoride microbubbles. The perfusion analysis was calculated using Peak, TTP, mTT and AUC with integrated software during the late arterial to early portal-venous phase for approximately 9 sec (5-15 sec). For the evaluation of the success after percutaneous treatment the perfusion results were compared to the follow-up control after 6 months with CT and MRI and CEUS. RESULTS: Perfusion analyses after percutaneous treatment of malignant liver lesions showed highly significant perfusion differences when comparing the center to the surrounding tissue and the margins (p<0.0001) for Peak and also for AUC. 62 lesions were successfully treated, meaning there was no local recurrence after 6 months. In cases of residual tumor CEUS showed a nodular marginal enhancement, the corresponding perfusion analyses showed nodular red and yellow pseudo-color shades. CONCLUSIONS: Using CEUS and perfusion analysis, a critical analysis of post-ablation defects in malignant liver lesions is possible. With the help of pseudo-colors, remaining tumor-vascularization can be detected.


Assuntos
Carcinoma Hepatocelular/diagnóstico por imagem , Meios de Contraste/uso terapêutico , Neoplasias Hepáticas/diagnóstico por imagem , Perfusão/métodos , Ultrassonografia/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Hepatocelular/cirurgia , Feminino , Humanos , Neoplasias Hepáticas/cirurgia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
13.
Diagn Interv Imaging ; 98(9): 583-588, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28818346

RESUMO

Navigation systems have the potential to achieve a high accuracy for percutaneous ablation of tumors even for those in difficult locations. In the last years, successful research has been conducted to make navigation devices applicable to percutaneous tumor ablation with special planning software that now allows high accuracy even for deep-located small lesions close to critical structures. Because of the high number of available navigation systems, this review focuses on those with preexisting clinical studies.


Assuntos
Neoplasias/diagnóstico por imagem , Neoplasias/cirurgia , Cirurgia Assistida por Computador , Técnicas de Ablação , Fenômenos Eletromagnéticos , Marcadores Fiduciais , Humanos , Procedimentos Cirúrgicos Robóticos , Software
14.
Sci Rep ; 7(1): 9460, 2017 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-28842662

RESUMO

Aim of this study was to compare low tube voltage computed tomography (80 kV) of the liver using iterative image reconstruction (SAFIRE) with standard computed tomography (120 kV) using filtered back-projection (FBP) for the detection of hepatocellular carcinoma (HCC). 46 patients (43 men) with 93 HCC confirmed by 3 T MRI with Gd-EOB-DPTA, in inconclusive cases combined with contrast-enhanced ultrasound, underwent dual-energy CT. The raw data of the 80 kV tube was reconstructed using the iterative reconstruction algorithm SAFIRE with two strengths (I3 and I5). The virtual 120 kV image data set was reconstructed using FBP. The CT images were reviewed to determine the lesion-to-liver contrast (LLC), the lesion contrast-to-noise ratio (CNR) and the sensitivity. The LLC (57.1/54.3 [I3/I5] vs. 34.9 [FBP]; p ≤ 0.01), CNR (3.67/4.45 [I3/I5] vs. 2.48 [FBP]; p < 0.01) and sensitivity (91.4%/88.2% [I3/I5] vs. 72.0% [FBP]; p ≤ 0.01) were significantly higher in the low-voltage protocol using SAFIRE. Therefore, low tube voltage CT using SAFIRE results in an increased lesion-to-liver contrast as well as an improved lesion contrast-to-noise ratio compared to FBP at 120 kV which results in a higher sensitivity for the detection of HCC.


Assuntos
Carcinoma Hepatocelular/diagnóstico , Neoplasias Hepáticas/diagnóstico , Fígado/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Meios de Contraste , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Fígado/patologia , Masculino , Pessoa de Meia-Idade , Imagens de Fantasmas , Estudos Prospectivos , Doses de Radiação , Sensibilidade e Especificidade , Tomografia Computadorizada por Raios X , Ultrassonografia
15.
Clin Hemorheol Microcirc ; 67(3-4): 383-388, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28885205

RESUMO

PURPOSE: To determine the influence of pre-interventionally existing portal vein thrombosis on the ablation success of percutaneous tumor ablation of HCC. MATERIALS AND METHODS: 15 patients with HCC and pre-existing portal vein thrombosis underwent thermal tumor ablation. We retrospectively analyzed the pre- and post-interventionally performed CT and MRI scans in terms of technical success as well as the complication rate. The portal vein thrombosis was classified into segmental, lobar and central thrombus. RESULTS: In 13/15 cases (87%) complete ablation with no evidence of residual tumor tissue was seen 6 weeks after the procedure in contrast-enhanced MRI scans and contrast-enhanced ultrasound (CEUS). No major and 2 minor complications were observed after the ablation procedure. CONCLUSION: Reduced perfusion due to pre-interventionally existing portal vein thrombosis has no significant impact on the ablation success or the complication rate.


Assuntos
Carcinoma Hepatocelular/complicações , Ablação por Cateter/métodos , Neoplasias Hepáticas/complicações , Veia Porta/patologia , Trombose Venosa/etiologia , Carcinoma Hepatocelular/patologia , Feminino , Humanos , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Trombose Venosa/patologia
16.
Clin Hemorheol Microcirc ; 67(3-4): 373-382, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28885204

RESUMO

PURPOSE: To compare the diagnostic performance of real-time maximum liver capacity (LiMAx) with dynamic contrast-enhanced ultrasound (CEUS)-based liver microcirculation. MATERIALS AND METHODS: 23 patients underwent liver function capacity (LiMAx) test and consecutive or previous CEUS examinations. A bolus injection of 1.4 ml sulfur hexafluoride microbubbles was administered for CEUS measurements (1-6 MHz) and quantitative perfusion analysis (TIC) was performed with an integrated perfusion software using stored cine-loops. Two perfusion-parameters, time to peak (TtoP) and area under the curve (Area), were evaluated in liver parenchyma and portal vein using TIC analysis.To compare quantification parameters, patients were classified in patients representing a healthy population (LiMAx value >315 µg/kg/h) and those representing patients with liver disease (LiMAx value <315 µg/kg/h). RESULTS: Comparing perfusion parameters derived from portal vein measurements, TtoP and Area were higher in patients with normal liver function TtoP: 25.0±8.4 s, Area: 1483±920 a.u. compared to patients with impaired liver function TtoP: 22.4±14.0 s; Area 1351±1212 a.u. This difference however was not statistically significant (p = 0.52, p = 0.48).In parameters derived from measurements in liver parenchyma TtoP was higher (38.5±11.3 s) and Area was lower (999±632 a.u.) in patients with normal liver function compared to patients with impaired liver function (TtoP; 30.6±11.0 s, p = 0.156; Area: 1202±719 a.u.) (p = 0.16, p = 0.56).In a simple linear regression model, none of the perfusion parameters measured in portal vein (TtoP portal, Area portal) and liver parenchyma (TtoP liver, Area liver) correlated significantly with respective LiMAx values (p = 0.194-0.950). CONCLUSION: Within the framework of this study, CEUS-based perfusion parameters were not able to assess severity of liver disease, assessed with LiMAx- test.


Assuntos
Meios de Contraste/uso terapêutico , Hepatopatias/fisiopatologia , Ultrassonografia/métodos , Feminino , Humanos , Hepatopatias/diagnóstico por imagem , Masculino , Microcirculação , Pessoa de Meia-Idade , Perfusão , Estudos Retrospectivos
17.
Clin Hemorheol Microcirc ; 67(3-4): 399-405, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28885207

RESUMO

OBJECTIVES: Irreversible electroporation (IRE) is a novel focal ablation technique applicable for treatment of prostate cancer (PCa). We aim to evaluate imaging findings of T1-weighted contrast-enhanced MRI after percutaneous IRE of low-risk PCa. METHODS: A total of 13 male patients underwent IRE of focal low-risk PCa and were included in this analysis. Prostate IRE was conducted using 2-4 electrodes being placed under CT-fluoroscopy guidance. Dynamic contrast-enhanced 3D isotropic fat-saturated T1-weighted MRI (DCE-MRI) was performed 24-72 hours before and 24-72 hours after ablation. RESULTS: Ablated prostate was either homogeneously (8/13 [62%]) or heterogeneously (5/13 [38%]) hypo attenuating. Peripheral contrast enhancement manifesting as a hyper attenuating margin was observed during the arterial (60 sec) (3/13 [23%]) and venous (240 sec) (10/13 [77%]) phase. The ablation defect showed a sharp (8/13 [62%]) or blurry (5/13 [38%]) margin. CONCLUSIONS: The results show a venous peripheral rim enhancement in most of the cases, indicating reactive hyperaemia. The heterogeneous appearance of the defect zone in some cases may be secondary to sustained vascularization.


Assuntos
Meios de Contraste/uso terapêutico , Eletroporação/métodos , Imageamento por Ressonância Magnética/métodos , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/cirurgia , Humanos , Masculino , Microcirculação , Pessoa de Meia-Idade , Neoplasias da Próstata/patologia
18.
Clin Hemorheol Microcirc ; 67(3-4): 445-451, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28885212

RESUMO

OBJECTIVE: To compare contrast-enhanced computed tomography (CT) and contrast-enhanced ultrasound (CEUS) for the quantitative evaluation of an ablation defect following radiofrequency ablation of malignant liver lesions in a prospective study. MATERIALS AND METHODS: 22 radiofrequency ablations of malignant liver tumors were performed. The ablation defects were then measured and evaluated by two independent examiners via contrast-enhanced computed tomography (CT) and contrast-enhanced ultrasound (CEUS) using a 1-5 MHz multifrequency convex ultrasound transducer (LOGIQ E9, GE) with respect to the short-axis diameter, the long-axis diameter, and the area. RESULTS: Quantitative evaluation of ablation defects is possible with both contrast-enhanced CT and CEUS. The average long-axis diameter was 47.1 mm (±11.08;±23,5%) on CEUS and 56.48 mm (±14.14;±25,0%) on CT; the short-axis diameter was 39.72 mm (±11.14;±28,05%) on CEUS and 40.27 mm (±10.50;±26,07%) on CT; the area was 1439.82 mm2 (±678.57;±47,13%) on CEUS and 2392.68 mm2 (1147.67;±48,0%) on CT. On average, ablation defects are assessed to be larger on CT than on CEUS. A significant correlation between the modalities could not be achieved for all measurement axes. CONCLUSION: CEUS can be used for the postinterventional detection and evaluation of ablation defects. However, these are always assessed to be larger on contrast-enhanced CT than CEUS.


Assuntos
Carcinoma Hepatocelular/diagnóstico por imagem , Ablação por Cateter/métodos , Meios de Contraste/uso terapêutico , Neoplasias Hepáticas/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Ultrassonografia/métodos , Carcinoma Hepatocelular/patologia , Feminino , Humanos , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
19.
Clin Hemorheol Microcirc ; 66(4): 277-282, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28527198

RESUMO

To evaluate the effectiveness of high-resolution contrast-enhanced ultrasound (CEUS) to diagnose early post-operative complications in an interdisciplinary intensive care unit.In 50 patients (male 32; female 18) 64 CEUS examinations were performed in an intensive care unit (ICU) setting to detect post-operative complications. Multi-frequency transducer (1-5 and/or 6-9 MHz) were used. All 64 examinations were performed by one experienced examiner. CEUS findings were compared with contrast-enhanced computed tomography (CECT) findings. CECT images were acquired within 1-24 hours after CEUS examination in arterial and portal-venous phases of the abdomen using either a 16-slice computed tomography scanner or a 128-dual slice computed tomography scanner.In 56 out of 64 cases (88%) the CEUS-based diagnosis corresponded with the CECT diagnosis. Vascular stenosis in hepatic arteries and portal veins were recognised in both imaging modalities but were evaluated differently [5 cases]. In 3 cases (5%) small peripheral splenic infarction, retroperitoneal hematoma and fluid collection around the liver were not diagnosed by CEUS. CONCLUSION: CEUS in an ICU setting enables a reliable detection of postoperative abdominal complications as compared to CECT.


Assuntos
Meios de Contraste/uso terapêutico , Unidades de Terapia Intensiva/normas , Complicações Pós-Operatórias/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Ultrassonografia/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/diagnóstico , Adulto Jovem
20.
Int J Comput Assist Radiol Surg ; 12(5): 803-809, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-27653615

RESUMO

OBJECTIVE: Comparison of conventional CT-guided manual irreversible electroporation (IRE) of malignant liver tumors and a robot-assisted approach regarding procedural accuracy, intervention time, dose, complications, and treatment success. METHODS: A retrospective single-center analysis of 40 cases of irreversible electroporation of malignant liver tumors in 35 patients (6 females, 29 males, average age 60.3 years). Nineteen of these ablation procedures were performed manually and 21 with robotic assistance. A follow-up (ultrasound, CT, and MRI) was performed after 6 weeks in all patients. RESULTS: The time from the planning CT scan to the start of the ablation as well as the dose-length product were significantly lower under robotic assistance (63.5 vs. 87.4 min, [Formula: see text]; 2132 vs. 4714 mGy cm, [Formula: see text]). The procedural accuracy, measured as the deviation of the IRE probes with respect to a defined reference probe, was significantly higher using robotic guidance (2.2 vs. 3.1 mm, [Formula: see text]). There were no complications. There was one incomplete ablation in the manual group. CONCLUSION: Robotic assistance for IRE of liver tumors allows for faster procedure times with higher accuracy while reducing radiation dose as compared to the manual placement of IRE probes.


Assuntos
Técnicas de Ablação/métodos , Carcinoma Hepatocelular/diagnóstico por imagem , Neoplasias Hepáticas/diagnóstico por imagem , Procedimentos Cirúrgicos Robóticos/métodos , Idoso , Eletrodos , Eletroporação , Feminino , Fluoroscopia/métodos , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Reprodutibilidade dos Testes , Projetos de Pesquisa , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/métodos , Resultado do Tratamento , Ultrassonografia
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