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1.
Eur Radiol ; 31(8): 5818-5829, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33486605

RESUMO

OBJECTIVES: Pancreatic cancer patients often have a high symptom burden, significantly impairing patients' quality of life (QOL). Nevertheless, there are hardly any reports on the impact of high-intensity focused ultrasound (HIFU) on the QOL of treated patients. For the first time, this study evaluated the effect of HIFU on QOL and compared these results in two European centers. METHODS: Eighty patients with advanced pancreatic cancer underwent HIFU (50 in Germany, 30 in Bulgaria). Clinical assessment included evaluation of QOL and symptoms using the EORTC QLQ-C30 questionnaire at baseline and 1, 3, and 6 months after HIFU. Pain intensity was additionally evaluated with the numerical rating score (NRS). RESULTS: Compared to baseline, global health significantly improved 3 and 6 months after HIFU treatment (p = 0.02). Functional subscales including physical, emotional, and social functioning were considerably improved at 6 months (p = 0.02, p = 0.01, and p = 0.01, respectively) as were leading symptom pain (p = 0.04 at 6 months), fatigue (p = 0.03 at 3 and p = 0.01 at 6 months), and appetite loss (p = 0.01 at 6 months). Moreover, pain intensity measured by NRS revealed effective and strong pain relief at all time points (p < 0.001). Reported effects were independent of tumor stage, metastatic status, and country of treatment. CONCLUSIONS: This study showed that HIFU represents an effective treatment option of advanced pancreatic cancer improving QOL by increasing global health and mitigation of physical complaints with a low rate of side effects, independent of the examiner. Therefore, HIFU is a worthwhile additional treatment besides systemic palliative chemotherapy or best supportive care in management of this aggressive disease. KEY POINTS: • In a prospective two-center study, it was shown that HIFU represents an effective treatment option of advanced pancreatic cancer improving QOL. • HIFU in pancreatic cancer patients is associated with a low rate of side effects, independent of the performer. • HIFU is a worthwhile additional treatment besides systemic palliative chemotherapy or best supportive care in management of this aggressive disease.


Assuntos
Ablação por Ultrassom Focalizado de Alta Intensidade , Neoplasias Pancreáticas , Alemanha , Humanos , Neoplasias Pancreáticas/terapia , Estudos Prospectivos , Qualidade de Vida
2.
Radiology ; 295(2): 458-466, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32208098

RESUMO

Background Abnormalities of the central lymphatic system (CLS) are increasingly treated by interventional radiology approaches. Planning of these procedures, however, is challenging because of the lack of clinical imaging tools. Purpose To evaluate the clinical usefulness of contrast agent-enhanced interstitial transpedal MR lymphangiography in the preinterventional workup of lymphatic interventions in patients with thoracic chylous effusions. Materials and Methods Patients with chylous effusions evaluated from January 2014 and December 2017 were included in this retrospective analysis of transpedal MR lymphangiography. Indications were chylothorax (n = 19; 76%), cervical lymphatic fistula (n = 2; 8%), and combined chylothorax and chylous ascites (n = 4; 16%). Patients underwent transpedal MR lymphangiography at 1.5 T with T1-weighted imaging after interstitial pedal of gadolinium-based contrast medium under local anesthesia. Contrast-enhanced MRI was evaluated for technical success, depiction of pathologic abnormalities of the CLS, and access site for lymphatic interventions (ie, clinically useful examination). Reader agreement for image quality and overall degree of visualization was assessed with weighted κ. Interrelations between overall image quality and degree of visualization of CLS structures were assessed by Spearman ρ. Efficacy of transpedal MR lymphangiography was calculated by using radiographic lymphangiography as the reference standard. Results Twenty-five patients (mean age, 54 years ± 18 [standard deviation]; 13 men) were evaluated. Eight percent (two of 25) of examinations failed (lymphoma in one patient and technical failure in one patient). Contrast agent injection was well tolerated without complications. Interrater agreement of image quality was excellent (κ = 0.96). The degree of CLS visualization correlated with overall image quality (ρ = 0.71; P < .001). Retroperitoneal lymphatics, cisterna chyli, and thoracic duct were viewed with an accuracy of 23 of 25 (92%), 24 of 25 (96%), and 23 of 25 (92%), respectively. Anatomic variations, a lymphatic pathologic abnormality, and interventional access routes were identified with an accuracy of 22 of 25 (88%), 23 of 25 (92%), and 24 of 25 (96%), respectively. Overall, 23 of 25 (92%) transpedal MR lymphangiograms provided clinically useful information. Conclusion Transpedal interstitial MR lymphangiography was well tolerated by the patient and identified specific pathologic abnormalities causing thoracic chylous leakages before lymphatic intervention. © RSNA, 2020 Online supplemental material is available for this article. See also the editorial by Maki and Itkin in this issue.


Assuntos
Quilotórax/diagnóstico por imagem , Meios de Contraste/administração & dosagem , Óleo Etiodado/administração & dosagem , Sistema Linfático/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Ascite Quilosa/diagnóstico por imagem , Feminino , , Humanos , Injeções Intradérmicas , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
3.
Neuroradiology ; 62(9): 1111-1122, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32363482

RESUMO

PURPOSE: Magnetic resonance-guided focused ultrasound (MRgFUS) systems are increasingly used to non-invasively treat tremor; consensus on imaging follow-up is poor in these patients. This study aims to elucidate how MRgFUS lesions evolve for a radiological readership with regard to clinical outcome. METHODS: MRgFUS-induced lesions and oedema were retrospectively evaluated based on DWI, SWI, T2-weighted and T1-weighted 3-T MRI data acquired 30 min and 3, 30 and 180 days after MRgFUS (n = 9 essential tremor, n = 1 Parkinson's patients). Lesions were assessed volumetrically, visually and by ADC measurements and compared with clinical effects using non-parametric testing. RESULTS: Thirty minutes after treatment, all lesions could be identified on T2-weighted images. Immediate oedema was rare (n = 1). Lesion volume as well as oedema reached a maximum on day 3 with a mean lesion size of 0.4 ± 0.2 cm3 and an oedema volume 3.7 ± 1.2 times the lesion volume. On day 3, a distinct diffusion-restricted rim was noted that corresponded well with SWI. Lesion shrinkage after day 3 was observed in all sequences. Lesions were no longer detectable on DWI in n = 7/10, on T2-weighted images in n = 4/10 and on T1-weighted images in n = 4/10 on day 180. No infarcts or haemorrhage were observed. There was no correlation between lesion size and initial motor skill improvement (p = 0.99). Tremor reduction dynamics correlated strongly with lesion shrinkage between days 3 and 180 (p = 0.01, R = 0.76). CONCLUSION: In conclusion, cerebral MRgFUS lesions variably shrink over months. SWI is the sequence of choice to identify lesions after 6 months. Lesion volume is arguably associated with intermediate-term outcome.


Assuntos
Tremor Essencial/terapia , Imagem por Ressonância Magnética Intervencionista , Doença de Parkinson/terapia , Tálamo/diagnóstico por imagem , Terapia por Ultrassom , Idoso , Tremor Essencial/diagnóstico por imagem , Feminino , Seguimentos , Humanos , Masculino , Doença de Parkinson/diagnóstico por imagem , Estudos Retrospectivos
4.
BMC Cancer ; 19(1): 1024, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31666035

RESUMO

BACKGROUND: Research shows disparities in cancer outcomes by ethnicity or socio-economic status. Therefore, it is the aim of our study to perform a matched-pair analysis which compares the outcome of German and non-German (in the following described as 'foreign') cancer patients being treated at the Center for Integrated Oncology (CIO) Köln Bonn at the University Hospital of Bonn between January 2010 and June 2016. METHODS: During this time, 6314 well-documented patients received a diagnosis of cancer. Out of these patients, 219 patients with foreign nationality could be matched to German patients based on diagnostic and demographic criteria and were included in the study. All of these 438 patients were well characterized concerning survival data (Overall survival, Progression-free survival and Time to progression) and response to treatment. RESULTS: No significant differences regarding the patients' survival and response rates were seen when all German and foreign patients were compared. A subgroup analysis of German and foreign patients with head and neck cancer revealed a significantly longer progression-free survival for the German patients. Differences in response to treatment could not be found in this subgroup analysis. CONCLUSIONS: In summary, no major differences in survival and response rates of German and foreign cancer patients were revealed in this study. Nevertheless, the differences in progression-free survival, which could be found in the subgroup analysis of patients with head and neck cancer, should lead to further research, especially evaluating the role of infectious diseases like human papillomavirus (HPV) and Epstein-Barr virus (EBV) on carcinogenesis and disease progression.


Assuntos
Neoplasias dos Genitais Femininos/etnologia , Neoplasias dos Genitais Femininos/mortalidade , Neoplasias de Cabeça e Pescoço/etnologia , Neoplasias de Cabeça e Pescoço/mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Neoplasias dos Genitais Femininos/terapia , Alemanha/etnologia , Neoplasias de Cabeça e Pescoço/terapia , Humanos , Estimativa de Kaplan-Meier , Masculino , Análise por Pareamento , Pessoa de Meia-Idade , Intervalo Livre de Progressão , Estudos Retrospectivos , População Branca , Adulto Jovem
5.
J Sleep Res ; 28(3): e12665, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-29411477

RESUMO

Fatigue and sleep deprivation are common phenomena, especially among medical professionals and shift workers. Studies have proven that short episodes of sleep deprivation can lead to sympathetic hyperactivity with an elevation in blood pressure, heart rate, and an increased secretion of stress hormones (e.g. cortisol, noradrenaline, thyroid hormones). In this study investigating cardiac strain in 20 healthy subjects undergoing short-term sleep deprivation, it could be shown for the first time that 24-hr-shift-related short-term sleep deprivation leads to a significant increase in cardiac contractility, blood pressure, heart rate and stress hormone secretion. These findings may help better understand how workload and shift duration affect public health, and lay the foundation for further investigations.


Assuntos
Doenças Cardiovasculares/etiologia , Fadiga/etiologia , Imageamento por Ressonância Magnética/métodos , Transtornos do Sono do Ritmo Circadiano/complicações , Adulto , Doenças Cardiovasculares/patologia , Feminino , Humanos , Masculino , Privação do Sono/fisiopatologia
6.
Eur Radiol ; 29(9): 4709-4717, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30689036

RESUMO

OBJECTIVES: To investigate the clinical potential of fat-free muscle area (FFMA) to predict outcome in patients with liver-predominant metastatic colorectal cancer (mCRC) undergoing radioembolization (RE) with 90Yttrium microspheres. METHODS: Patients with mCRC who underwent RE in our center were included in this retrospective study. All patients received liver magnetic resonance imaging including standard T2-weighted images. The total erector spinae muscle area and the intramuscular adipose tissue area were measured at the level of the origin of the superior mesenteric artery and subtracted to calculate FFMA. Cutoff values for definition of low FFMA were 3644 mm2 in men and 2825 mm2 in women. The main outcome was overall survival (OS). For survival analysis, the Kaplan-Meier method and Cox regressions comparing various clinic-oncological parameters which potentially may affect OS were performed. RESULTS: Seventy-seven patients (28 female, mean age 60 ± 11 years) were analyzed. Mean time between MRI and the following RE was 17 ± 31 days. Median OS after RE was 178 days. Patients with low FFMA had significantly shortened OS compared to patients with high FFMA (median OS: 128 vs. 273 days, p = 0.017). On multivariate Cox regression analysis, OS was best predicted by FFMA (hazard ratio (HR) 2.652; p < 0.001). Baseline bilirubin (HR 1.875; p = 0.030), pattern of tumor manifestation (HR 1.679; p = 0.001), and model of endstage liver disease (MELD) score (HR 1.164; p < 0.001) were also significantly associated with OS. CONCLUSIONS: FFMA was associated with OS in patients receiving RE for treatment of mCRC and might be a new prognostic biomarker for survival prognosis. KEY POINTS: • Fat-free muscle area (FFMA) as a measure of lean muscle area predicts survival in metastatic colorectal liver cancer following radioembolization. • FFMA can easily be assessed from routine pre-interventional liver magnetic resonance imaging. • FFMA might be a new promising biomarker for assessment of sarcopenia.


Assuntos
Braquiterapia/métodos , Neoplasias Colorretais/patologia , Neoplasias Hepáticas/radioterapia , Imageamento por Ressonância Magnética/métodos , Músculo Esquelético/diagnóstico por imagem , Radioisótopos de Ítrio/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Neoplasias Hepáticas/secundário , Masculino , Microesferas , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Análise de Sobrevida
7.
J Vasc Interv Radiol ; 30(1): 110-117, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30527658

RESUMO

PURPOSE: To evaluate polymerization of N-butyl cyanoacrylate (NBCA)/iodized oil mixtures for lymphatic interventions in vitro. MATERIALS AND METHODS: Polymerization times of different NBCA/iodized oil mixtures (ratios of 1:0-1:7) were investigated in a static and dynamic experimental setup (performed in a lymph flow model in a silicone tube). Eight lymphatic samples with different triglyceride (TG) concentrations (low TGs, < 50 mg/dL; medium TGs, approximately 100-400 mg/dL; high TGs, > 700 mg/dL) were investigated. Morphologic changes during NBCA polymerization were monitored and recorded by video. Statistical analysis was performed with intergroup comparisons (Kruskal-Wallis test) and multiple regression analysis. RESULTS: Static experiments showed increasing polymerization times with increasing concentrations of iodized oil as well as increasing concentrations of TGs. In the low-TG group, polymerization time increased from 14 s at a 1:1 ratio of NBCA to iodized oil to 1,336 s at a 1:7 ratio; times in the medium-TG group increased from 21 s (1:1) to 2,546 s (1:7), and those in the high TG group increased from 168 s (1:1) to 16,530 s (1:7). In dynamic experiments, prolongation of polymerization time was less pronounced. For low- and medium-TG groups, total occlusion of the silicon tube was observed in all cases during the embolization procedure at between 26 seconds (1:1 ratio) and 52 seconds (1:7). In the high-TG group, polymerization took considerably longer (between 43 s [1:1] and 467 s [1:7]) or failed completely. CONCLUSIONS: Polymerization time of NBCA/iodized oil in lymph seems to be prolonged by increasing iodized oil and TG concentrations.


Assuntos
Embolização Terapêutica/métodos , Embucrilato/química , Óleo Iodado/química , Doenças Linfáticas/terapia , Embucrilato/administração & dosagem , Humanos , Óleo Iodado/administração & dosagem , Cinética , Linfa/química , Modelos Anatômicos , Polimerização , Triglicerídeos/química
8.
J Cardiovasc Magn Reson ; 21(1): 54, 2019 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-31462282

RESUMO

BACKGROUND: Myocardial T1 and T2 mapping are reliable diagnostic markers for the detection and follow up of acute myocarditis. The aim of this study was to compare the diagnostic performance of current mapping measurement approaches to differentiate between myocarditis patients and healthy individuals. METHODS: Fifty patients with clinically defined acute myocarditis and 30 healthy controls underwent cardiovascular magnetic resonance (CMR). Myocardial T1 relaxation times, T2 relaxation times, left ventricular (LV) function, T2 ratio, early gadolinium enhancement ratio, and presence of late gadolinium enhancement (LGE) were analysed. Native T1 and T2 relaxation times, as well as extracellular volume fraction (ECV) were measured for the entire LV myocardium (global), within the midventricular short axis slice (mSAX), within the midventricular septal wall (ConSept), and within the remote myocardium (remote). Receiver operating characteristics analysis was performed to compare diagnostic performance. RESULTS: All measurement approaches revealed significantly higher native T1 and T2 relaxation times as well as ECV values in patients compared to healthy controls (p < 0.05 for all parameters). The global measurement approach showed highest diagnostic performance regarding all mapping parameters (AUCs, native T1: 0.903, T2: 0.847, ECV: 0.731). Direct comparison of the different measurement approaches revealed significant differences in diagnostic performance between the global and the remote approach regarding T1 relaxation times and ECV (p = 0.001 and p = 0.002 respectively). Further, the global measurement approach revealed significantly higher T1 relaxation times compared to the ConSept approach (AUCs: 0.903 vs. 0.783; p = 0.003) and nearly significant differences compared to the mSAX approach (AUC: 0.850; p = 0.051). T2 relaxation times showed no significant differences between all measurement approaches (p > 0.050 for all parameters). CONCLUSIONS: Native T1 and T2 mapping allow for accurate detection of acute myocarditis irrespective of the measurement approach used. Even measurements performed exclusively within remote myocardium allow for reliable detection of acute myocarditis, demonstrating diffuse involvement of disease despite a mostly regional or patchy distribution pattern of visible pathologies. The global measurement approach provides the overall best diagnostic performance in acute myocarditis for both T1 and T2 mapping.


Assuntos
Imagem Cinética por Ressonância Magnética , Miocardite/diagnóstico por imagem , Miocárdio/patologia , Doença Aguda , Adulto , Estudos de Casos e Controles , Meios de Contraste/administração & dosagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Miocardite/patologia , Compostos Organometálicos/administração & dosagem , Valor Preditivo dos Testes , Estudos Prospectivos , Reprodutibilidade dos Testes , Adulto Jovem
9.
Thorac Cardiovasc Surg ; 67(2): 86-91, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-29080557

RESUMO

BACKGROUND: Temporary transmyocardial pacing leads (TTPLs) represent an absolute contraindication to magnetic resonance imaging (MRI). The purpose of this study was to evaluate the safety and feasibility of MRI at 1.5 Tesla (T) using a transmit/receive (T/R) head coil in patients with TTPL. METHODS: TTPLs (220 cm, Osypka TME, Dr. Osypka GmbH, Rheinfelden, Germany) were implanted in a phantom and exposed to conditions of a 1.5 T brain examination using a T/R head coil. Temperature changes at the lead tip were continuously recorded. A total of 28 patients with TTPL and an urgent indication for a brain MRI underwent MRI at 1.5 T with vital sign monitoring. A T/R head coil was used to minimize radiofrequency exposure of the TTPL. Before and immediately after the MRI scan, TTPL lead impedance, pacing capture threshold (PCT), signal slope, and sensing were measured. Serum troponin I was determined before and after MRI to detect thermal myocardial injury. RESULTS: In vitro, the maximum temperature increase from radiofrequency-induced heating of the TTPL tip was < 1°C. In vivo, no complications, such as heating sensations, dizziness, unexpected changes in heart rate or rhythm, or other unusual signs or symptoms were observed. No significant changes in the lead impedance, PCT, signal slope, or sensing were recorded. There were no increases of serum troponin I after the MRI examination. CONCLUSIONS: MRI of the brain may be performed safely at 1.5 T using a T/R head coil in case of an urgent clinical need in patients with TTPL and may be considered a feasible and safe procedure when appropriate precautionary measures are taken.


Assuntos
Isquemia Encefálica/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética , Marca-Passo Artificial , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Imagem de Difusão por Ressonância Magnética/efeitos adversos , Imagem de Difusão por Ressonância Magnética/instrumentação , Desenho de Equipamento , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Marca-Passo Artificial/efeitos adversos , Segurança do Paciente , Imagens de Fantasmas , Valor Preditivo dos Testes , Medição de Risco , Fatores de Risco , Troponina I/sangue
10.
Ultraschall Med ; 40(5): 625-637, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29665583

RESUMO

PURPOSE: Pancreatic cancer (PaC) is a life-limiting tumor with a wide range of incapacitating symptoms such as cancer pain in more than 80 % of patients. This prospective interventional study addresses the clinical effectiveness of ultrasound-guided high-intensity focused ultrasound (HIFU) treatment for patients with advanced-stage PaC, including pain perception, tumor size and survival benefit. MATERIALS AND METHODS: 50 patients with late-stage PaC underwent HIFU. Clinical assessment included evaluation of tumor volume by imaging and pain burden (pain severity, pain sensation, interference with daily activities) using the Brief Pain Inventory at baseline and follow-up. Median overall survival, progression-free survival and time to local progression were estimated using Kaplan-Meier analysis. RESULTS: In 84 % of patients, significant early relief of cancer-induced abdominal pain was achieved by HIFU independent of metastatic status; it persisted during follow-up. Tumor volume reduction was 37.8 ±â€Š18.1 % after 6 weeks and 57.9 ± 25.9 % after 6 months. 21 % of HIFU-treated patients had local tumor progression with a median time of 14.4 months from intervention. The median overall survival and progression-free survival were 16.2 and 16.9 months from diagnosis and 8.3 and 6.8 months from intervention. CONCLUSION: In patients with advanced pancreatic cancer and otherwise limited treatment options, HIFU resulted in significant early and long-lasting pain relief and tumor size reduction over time independent of metastatic status. Clinical data suggest an additional potential survival benefit.


Assuntos
Ablação por Ultrassom Focalizado de Alta Intensidade , Neoplasias Pancreáticas , Adulto , Idoso , Idoso de 80 Anos ou mais , Tratamento por Ondas de Choque Extracorpóreas , Feminino , Ablação por Ultrassom Focalizado de Alta Intensidade/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/mortalidade , Neoplasias Pancreáticas/terapia , Estudos Prospectivos , Resultado do Tratamento
11.
Radiology ; 288(1): 226-333, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29514015

RESUMO

Purpose To establish and evaluate a visual score focused on entorhinal cortex atrophy (ERICA), as the entorhinal cortex is one of the first brain structures affected in Alzheimer disease (AD). Materials and Methods In this retrospective study, ERICA was visually evaluated with magnetic resonance imaging (2009-2016). First, a four-point ERICA score was developed by using data in 48 consecutive subjects (20 patients with AD and 28 control subjects). Then, in the main analysis, ERICA and the standard medial temporal lobe atrophy (MTA) scores were determined in an independent cohort of 60 patients suspected of having AD (mean age, 69.4 years; range, 46-86 years) and in 60 age-matched patients with subjective cognitive decline (SCD) (mean age, 72.4 years; range 50-87 years). Score performances were evaluated with κ statistics, receiver operating characteristic analysis, t tests, and analysis of variance according to the Standards for Reporting of Diagnostic Accuracy Studies. Results Patients with AD had higher MTA scores (mean, 2.13) and ERICA scores (mean, 2.05) than patients with SCD (P < .001). An ERICA score of 2 or greater achieved a higher diagnostic accuracy (91%) than the MTA score (74%), with a sensitivity of 83% versus 57% and a specificity of 98% versus 92% in discriminating dementia caused by AD from SCD (P < .001). The ERICA score was correlated with amyloid ß 42/40 ratio (ρ = -0.54, P < .001) and with cerebrospinal fluid tau (ρ = 0.35, P = .001) and p-tau (ρ = 0.31, P = .004). In multivariable linear regression analysis, ERICA was associated with verbal learning and recall (ß = -.40 and -.41), nonverbal recall (ß = -.28), and cued recall (ß = -.41, P ≤ .002 for all). Conclusion An ERICA score of 2 or greater indicates probable AD with high diagnostic accuracy. © RSNA, 2018 Online supplemental material is available for this article.


Assuntos
Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/patologia , Córtex Entorrinal/diagnóstico por imagem , Córtex Entorrinal/patologia , Imageamento por Ressonância Magnética/métodos , Idoso , Idoso de 80 Anos ou mais , Atrofia , Feminino , Alemanha , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Estudos Retrospectivos
12.
Radiology ; 288(3): 748-754, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29944086

RESUMO

Purpose To evaluate MRI T1 and T2 mapping with calculation of extracellular volume (ECV) for diagnosis and grading of liver fibrosis. Materials and Methods Different grades of fibrosis were induced in 60 male Sprague-Dawley rats by bile duct ligation (BDL) and carbon-tetrachloride (CCl4) intoxication. Portal pressure was measured invasively, whereas hepatic fibrosis was quantified by hydroxyproline content, Sirius red staining, and α smooth muscle actin staining. T1 values, T2 values, and ECV were assessed by using quantitative MRI mapping techniques. Results T1 values in animals 4 weeks after BDL were greater than in control animals (718 msec ± 74 vs 578 msec ± 33, respectively; P < .001). T2 values at 4 weeks were also greater in animals that underwent BDL than in control animals (46 msec ± 6 vs 29 msec ± 2, respectively; P < .001). Similar T1 and T2 findings were observed after CCl4 intoxication. ECV was greater in animals 4 weeks after BDL compared with control animals (31.3% ± 1.3 vs 18.2% ± 3.5, respectively; P < .001), with similar results after CCl4 intoxication. High correlations were found between ECV and hepatic hydroxyproline content (BDL: r = 0.68, P < .001; CCl4: r = 0.65, P < .001), Sirius red staining (BDL: r = 0.88, P < .001; CCl4: r = 0.82, P < .001), α smooth muscle actin staining (BDL: r = 0.70, P < .001; CCl4: r = 0.73, P < .001), and portal pressure (BDL: r = 0.54, P = .003; CCl4: r = 0.39, P = .043). Conclusion Elevation of T1 and T2 values and ECV was associated with severity of liver fibrosis and portal hypertension in an experimental animal model.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Cirrose Hepática/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Animais , Modelos Animais de Doenças , Fígado/diagnóstico por imagem , Fígado/patologia , Cirrose Hepática/patologia , Masculino , Ratos , Ratos Sprague-Dawley , Índice de Gravidade de Doença
13.
J Magn Reson Imaging ; 47(1): 255-261, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28429574

RESUMO

PURPOSE: To investigate the effect of the flip angle (FA) on the blood-myocardium contrast and to define the FA leading to highest image quality in contrast-enhanced balanced steady-state free precession (bSSFP) images. bSSFP images provide excellent contrast between myocardium and blood with high signal-to-noise and contrast-to-noise ratios (SNR, CNR). In clinical practice, bSSFP images are typically acquired following the injection of extracellular contrast agents (ECAs), although ECAs decrease the blood-myocardium contrast. MATERIALS AND METHODS: First, a theoretical optimization was performed to determine the FA that maximizes CNR in bSSFP imaging 2-20 minutes after application of ECA. Second signal-ratios, contrast, SNR, and CNR were assessed in vivo in 25 patients in bSSFP images at 1.5T acquired before (FA = 50°) and 10-15 minutes after (FAs = 50°, 80°, 90°, 100°) application of a double-dose contrast agent. Image quality was assessed by two readers. RESULTS: Simulations yielded FAs in the range of 85-100° for optimal CNR in contrast-enhanced images. In vivo comparison of conventionally acquired cine images (FA 50°) showed an increase in CNR between blood and myocardium by 57% in diastole and 78% in systole in adapted contrast-enhanced bSSFP images (FA 100°). Contrast-enhanced images with an FA of 100° were rated highest in image quality assessment. CONCLUSION: By means of FA adaptation a similar blood-myocardium contrast can be achieved in contrast-enhanced bSSFP as in unenhanced bSSFP imaging with an increase in CNR. LEVEL OF EVIDENCE: 1 Technical Efficacy: Stage 1 J. Magn. Reson. Imaging 2018;47:255-261.


Assuntos
Meios de Contraste/química , Coração/diagnóstico por imagem , Imagem Cinética por Ressonância Magnética , Miocárdio/patologia , Compostos Organometálicos/química , Adulto , Diástole , Processamento Eletrônico de Dados , Taxa de Filtração Glomerular , Ventrículos do Coração/diagnóstico por imagem , Humanos , Interpretação de Imagem Assistida por Computador , Processamento de Imagem Assistida por Computador , Pessoa de Meia-Idade , Estudos Prospectivos , Razão Sinal-Ruído , Sístole
14.
Catheter Cardiovasc Interv ; 91(4): 774-782, 2018 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-28547872

RESUMO

OBJECTIVES: To investigate the impact of aortic valve calcification and brain morphology on acute peri-procedural cerebrovascular events (CVEs) in patients undergoing transcatheter aortic valve implantation (TAVI). BACKGROUND: Aortic valve calcification and stenosis can be assessed with echocardiography. Cerebral magnetic resonance imaging (MRI) depicts and quantifies morphological signs of hypoperfusion and vascular embolism, which is of special interest in patients with severe aortic stenosis. Furthermore, subjects who undergo TAVI are prone to suffer of clinically silent peri-procedural CVEs. METHODS: A total of 119 patients referred to TAVI were investigated for aortic valve calcification using trans-esophageal echocardiography. Cerebral MRI prior to and immediate after implantation was performed in all patients using a dedicated scan protocol. Prior to TAVI, brain morphology was characterized. Post TAVI, brains were investigated for the onset of acute peri-procedural CVEs using diffusion weighted imaging (DWI). RESULTS: Seventy-eight patients (65.5%) revealed acute peri-procedural CVEs on MRI after TAVI with a favor of the left hemisphere (57.5%). The degree of valve calcification was associated with peri-procedural CVEs. Patients with a high WML burden had an increased risk for CVEs ((OR) 2.36 (95% CI: 1.09-5.15; P = 0.037)), especially when distributed periventricular ((OR: 3.27; 95% CI: 1.47-7.26; P = 0.0038)). CONCLUSION: In patients undergoing TAVI, the degree of aortic valve calcification and periventricular WML burden were correlated with acute peri-procedural CVEs. Future studies are needed to evaluate their independent value for the long-term clinical outcome.


Assuntos
Estenose da Valva Aórtica/cirurgia , Valva Aórtica/patologia , Valva Aórtica/cirurgia , Calcinose/cirurgia , Transtornos Cerebrovasculares/etiologia , Leucoencefalopatias/complicações , Substituição da Valva Aórtica Transcateter/efeitos adversos , Idoso , Idoso de 80 Anos ou mais , Valva Aórtica/diagnóstico por imagem , Valva Aórtica/fisiopatologia , Estenose da Valva Aórtica/complicações , Estenose da Valva Aórtica/diagnóstico por imagem , Estenose da Valva Aórtica/fisiopatologia , Doenças Assintomáticas , Calcinose/complicações , Calcinose/diagnóstico por imagem , Calcinose/fisiopatologia , Transtornos Cerebrovasculares/diagnóstico por imagem , Transtornos Cerebrovasculares/fisiopatologia , Imagem de Difusão por Ressonância Magnética , Ecocardiografia Transesofagiana , Feminino , Hemodinâmica , Humanos , Leucoencefalopatias/diagnóstico por imagem , Masculino , Medição de Risco , Fatores de Risco , Índice de Gravidade de Doença , Resultado do Tratamento
15.
Acta Radiol ; 59(1): 65-71, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28440670

RESUMO

Background Aortic stiffness and epicardial fat relate to cardiovascular risk. Their relationship with each other and their role with hypertension, diabetes mellitus (DM), and myocardial infarction (MI) can be evaluated by cardiac magnetic resonance (CMR). Purpose To explore an association between aortic stiffness and epicardial as well as paracardial fat volume (EFV and ParaFV, respectively) in hypertensive patients and to relate the results to the presence of DM and MI. Material and Methods A total of 156 hypertensive and 20 non-hypertensive participants were examined at 1.5 Tesla. A 2D-velocity-encoded sequence was acquired to assess aortic pulse wave velocity (PWV in m/s) as a measure of aortic stiffness. A 3D-Dixon sequence was used to determine EFV and ParaFV. Results PWV correlated with EFV (R = 0.474; P < 0.001), but not with ParaFV. Fat volumes (in mL/m2) and PWV were lower in non-hypertensive controls compared to hypertensive patients. EFV and PWV were significantly higher in diabetic hypertensive patients without MI (n = 19; PWV: 10.4 ± 2.9; EFV: 92.5 ± 19.3) compared to hypertension-only patients (n = 84 [no DM or MI]; EFV: 64.8 ± 25.1, PWV: 9.0 ± 2.6; P < 0.05). Logistic regression analysis showed a significant association between the presence of a MI and a higher EFV ( P < 0.05), but not with PWV ( P = 0.060) or ParaFV ( P = 0.375). Conclusion A relationship between aortic stiffness and EFV was found in hypertensive patients. Both were increased in the presence of DM; however, only EFV was increased in the presence of MI. This may relate to the PWV lowering effect of the antihypertensive medication used by hypertensive patients and underscores the benefit of EFV assessment in this regard.


Assuntos
Tecido Adiposo/diagnóstico por imagem , Diabetes Mellitus/diagnóstico por imagem , Hipertensão/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Infarto do Miocárdio/diagnóstico por imagem , Rigidez Vascular/fisiologia , Tecido Adiposo/patologia , Tecido Adiposo/fisiopatologia , Aorta/diagnóstico por imagem , Aorta/patologia , Aorta/fisiopatologia , Diabetes Mellitus/patologia , Diabetes Mellitus/fisiopatologia , Feminino , Humanos , Hipertensão/patologia , Hipertensão/fisiopatologia , Imageamento Tridimensional/métodos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/patologia , Infarto do Miocárdio/fisiopatologia , Pericárdio/diagnóstico por imagem , Pericárdio/patologia , Pericárdio/fisiopatologia , Estudos Prospectivos , Fatores de Risco
16.
Ultraschall Med ; 39(6): 650-658, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29346805

RESUMO

PURPOSE: To evaluate the effects of HIFU therapy on visceral vessel patency in patients with inoperable locally invasive pancreatic cancer. MATERIALS AND METHODS: 50 pancreatic cancer patients (26 men, 24 women) aged 41 - 82 years (65.0 ±â€Š10.2) underwent ultrasonography (US) and computed tomography (CT) examinations before and within one day after HIFU treatment, as well as at follow-up at six weeks, three months and six months. Evaluation and grading were performed by two experienced independent radiologists according to a classification scheme based on vessel involvement, vessel diameter, patency, and defects in flow. RESULTS: Before HIFU treatment, arterial vessel involvement was noted in 42 patients, venous involvement in 47, and 47 patients presented with both. Superior mesenteric artery occlusion was found in three carcinomas while nearly half of the cases (n = 24) displayed signs of superior mesenteric vein, portal vein, or splenic vein occlusion. High-grade tumor-associated arterial narrowing was seen in ten patients. Despite vessel encasement and partially extensive propagation of collateral vessels, it was possible to safely perform HIFU treatment in all patients without complications. US and CT studies performed within one day after therapy did not show any change in vessel patency in 47 patients (94 %). Follow-up controls at the six-week mark revealed increased vessel narrowing and finally occlusion after six months in 11 patients due to tumor progression. CONCLUSION: This study demonstrates that HIFU treatment can be safely applied to pancreatic cancers enveloping large mesenteric vessels despite vessel narrowing or extensive collateral propagation. Most patients (94 %) did not experience adverse effects regarding vessel patency.


Assuntos
Tratamento por Ondas de Choque Extracorpóreas , Mesentério , Neoplasias Pancreáticas , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Mesentério/irrigação sanguínea , Mesentério/patologia , Pessoa de Meia-Idade , Invasividade Neoplásica , Pâncreas , Neoplasias Pancreáticas/complicações , Neoplasias Pancreáticas/patologia , Veia Porta , Resultado do Tratamento
17.
J Neuroradiol ; 45(4): 242-248, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29410063

RESUMO

BACKGROUND AND PURPOSE: Kinetic parameters of T1-weighted dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) are considered to be influenced by microvessel environment. This study was performed to explore the extent of this association for meningiomas. MATERIALS AND METHODS: DCE-MRI kinetic parameters (contrast agent transfer constants Ktrans and kep, volume fractions vp and ve) were determined in pre-operative 3T MRI of meningioma patients for later biopsy sites (19 patients; 15 WHO Io, no previous radiation, and 4 WHO IIIo pre-radiated recurrent tumors). Sixty-three navigated biopsies were consecutively retrieved. Biopsies were immunohistochemically investigated with endothelial marker CD34 and VEGF antibodies, stratified in a total of 4383 analysis units and computationally assessed for VEGF expression and vascular parameters (vessel density, vessel quantity, vascular fraction within tissue [vascular area ratio], vessel wall thickness). Derivability of kinetic parameters from VEGF expression or microvascularization was determined by mixed linear regression analysis. Tissue kinetic and microvascular parameters were tested for their capacity to identify the radiation status in a subanalysis. RESULTS: Kinetic parameters were neither significantly related to the corresponding microvascular parameters nor to tissue VEGF expression. There was no significant association between microvessel density and its presumed correlate vp (P=0.07). The subgroup analysis of high-grade radiated meningiomas showed a significantly reduced microvascular density (AUC 0.91; P<0.0001) and smaller total vascular fraction (AUC 0.73; P=0.01). CONCLUSIONS: In meningioma, DCE-MRI kinetic parameters neither allow for a reliable prediction of tumor microvascularization, nor for a prediction of VEGF expression. Kinetic parameters seem to be determined from different independent factors.


Assuntos
Imageamento por Ressonância Magnética/métodos , Neoplasias Meníngeas , Meningioma , Microvasos/patologia , Fator A de Crescimento do Endotélio Vascular/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Meios de Contraste , Feminino , Humanos , Aumento da Imagem , Biópsia Guiada por Imagem , Masculino , Neoplasias Meníngeas/irrigação sanguínea , Neoplasias Meníngeas/diagnóstico por imagem , Neoplasias Meníngeas/metabolismo , Meninges/irrigação sanguínea , Meninges/patologia , Meningioma/irrigação sanguínea , Meningioma/diagnóstico por imagem , Meningioma/metabolismo , Pessoa de Meia-Idade
18.
Radiology ; 283(2): 361-370, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28221097

RESUMO

Purpose To investigate the utility and accuracy of breast magnetic resonance (MR) imaging as a supplemental screening tool in women at average risk for breast cancer and to investigate the types of cancer detected with MR imaging screening. Materials and Methods This prospective observational study was conducted at two academic breast centers in women aged 40-70 years without breast cancer-associated risk factors (lifetime risk <15%). Between January 2005 and December 2013, women with at least minimal residual breast tissue (American College of Radiology categories A-D) and normal conventional imaging findings (screening mammography with or without screening ultrasonography [US]) were invited to undergo supplemental MR imaging screening. Outcome measures were supplemental cancer detection rates, interval cancer rates, and biologic profiles of MR imaging-detected additional cancers, as well as specificity and positive predictive value (PPV) of MR imaging screening. Tissue diagnoses or 2 years of follow-up were used to establish the reference standard. Results A total of 2120 women were recruited and underwent 3861 screening MR imaging studies, covering an observation period of 7007 women-years. Breast MR imaging depicted 60 additional breast cancers (ductal carcinoma in situ, n = 20; invasive carcinoma, n = 40) for an overall supplemental cancer detection rate of 15.5 per 1000 cases (95% confidence interval [CI]: 11.9, 20.0). Forty-eight additional cancers were detected with MR imaging at initial screening (supplemental cancer detection rate, 22.6 per 1000 cases). During the 1741 subsequent screening rounds, 12 of 13 incident cancers were found with MR imaging alone (supplemental cancer detection rate, 6.9 per 1000 cases). One cancer was diagnosed with all three methods (mammography, US, and MR imaging), and none were diagnosed with mammography only or US only. Cancers diagnosed with MR imaging were small (median, 8 mm), node negative in 93.4% of cases, and dedifferentiated (high-grade cancer) in 41.7% of cases at prevalence screening and 46.0% of cases at incidence screening. No interval cancers were observed. MR imaging screening offered high specificity (97.1%; 95% CI: 96.5, 97.6) and high PPV (35.7%; 95% CI: 28.9, 43.1). Conclusion In women at average risk for breast cancer, MR imaging screening improves early diagnosis of prognostically relevant breast cancer. © RSNA, 2017 Online supplemental material is available for this article.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/epidemiologia , Detecção Precoce de Câncer/estatística & dados numéricos , Imageamento por Ressonância Magnética/estatística & dados numéricos , Mamografia/estatística & dados numéricos , Adulto , Distribuição por Idade , Idoso , Detecção Precoce de Câncer/métodos , Feminino , Alemanha/epidemiologia , Humanos , Estudos Longitudinais , Imageamento por Ressonância Magnética/métodos , Mamografia/métodos , Pessoa de Meia-Idade , Prevalência , Reprodutibilidade dos Testes , Medição de Risco/métodos , Sensibilidade e Especificidade
19.
J Magn Reson Imaging ; 46(4): 1187-1199, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28152250

RESUMO

PURPOSE: To investigate the effect of the choice of the curve-fitting model on the perfusion fraction (fIVIM ) with regard to tissue type characterization, correlation with microvascular anatomy, and dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) parameters. Several curve-fitting models coexist in intravoxel incoherent motion (IVIM) MRI to derive the (fIVIM ). MATERIALS AND METHODS: In all, 29 patients with brain lesions (12 gliomas, 11 meningiomas, three metastases, two gliotic scars, one multiple sclerosis) underwent IVIM-MRI (32 b-values, 0 to 2000 s/mm2 ) at 3T. fIVIM was determined by classic monoexponential, biexponential, and a novel nonnegative least squares (NNLS) fitting in 352 regions of interest (lesion-containing and normal-appearing tissue) and tested their correlation with DCE-MRI kinetic parameters and microvascular anatomy derived from 57 region of interest (ROI)-based biopsies and their capacities to differentiate histologically different lesions. RESULTS: fIVIM differed significantly between all three models and all tissue types (monoexponential confidence interval in percent [CI 3.4-3.8]; biexponential [CI 11.21-12.45]; NNLS [CI 2.06-2.60]; all P < 0.001). For all models an increase in fIVIM was associated with a shift to larger vessels and higher vessel area / tissue area ratio (regression coefficient 0.07-0.52; P = 0.04-0.001). Correlation with kinetic parameters derived from DCE-MRI was usually not significant. Only biexponential fitting allowed differentiation of both gliosis from edema and high- from low-grade glioma (both P < 0.001). CONCLUSION: The curve-fitting model has an important impact on fIVIM and its capacity to differentiate tissues. fIVIM may possibly be used to assess microvascular anatomy and is weakly correlated with DCE-MRI kinetic parameters. LEVEL OF EVIDENCE: 2 Technical Efficacy: Stage 1 J. Magn. Reson. Imaging 2017;46:1187-1199.


Assuntos
Neoplasias Encefálicas/diagnóstico por imagem , Meios de Contraste , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Encéfalo/diagnóstico por imagem , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
20.
Amino Acids ; 49(2): 273-281, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27812894

RESUMO

Breast cancer is a multifactorial disease classified by several sub-types which differ from each other by risk factors, specific molecular promoters and severity of outcomes. Tumour aggressiveness and metastatic disease are the key determinants of breast cancer outcomes. Tumour cell ability to degrade the extracellular matrix and to be motile is the hallmark of invasion and essential step in a development of breast cancer metastatic disease. Therefore, a coordinated action between cell motility and ability to degrade the extracellular matrix is currently under extensive investigation focused on molecular targets for both diagnostic and therapeutic purposes. Contextually, our current study was dedicated to patient stratification utilising MMP-9 serum activity levels and RhoA expression patterns measured in circulating leucocytes. Biomarker patterns were "masked" in non-stratified patient groups. In contrast, the multiparametric stratification approach led to highly improved clinical utility of biomarker patterns. Presented stratification system is recommended for population screening as a cost-effective non-invasive approach to facilitate predictive diagnostics of breast cancer predisposition, pre-lesions and early stages, when the pathology can be effectively prevented or cured. Proposed approach might be particularly useful for early and predictive breast cancer diagnostics applied to certain phenotypes such as premenopausal rather than postmenopausal women, women with dense breast tissue, where highly increased RhoA/MMPs activities are utilised for effective proteolysis of the matrix and cancer cell migration into dense matrices, as well as for breast cancer of unclear origin such as particularly aggressive triple-negative sub-type.


Assuntos
Neoplasias da Mama/sangue , Leucócitos/metabolismo , Metaloproteinase 9 da Matriz/sangue , Proteína rhoA de Ligação ao GTP/metabolismo , Adulto , Biomarcadores Tumorais/metabolismo , Doenças Mamárias/patologia , Neoplasias da Mama/diagnóstico , Feminino , Humanos , Pessoa de Meia-Idade , Pós-Menopausa , Pré-Menopausa , Medição de Risco/métodos
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