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1.
Scand J Med Sci Sports ; 28(4): 1397-1403, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29239051

RESUMO

The aim of the study was to evaluate the diagnostic accuracy of carotid ultrasound (CU) to predict coronary atherosclerosis in asymptomatic male marathon runners. A total of 49 male marathon runners older than 45 years (mean age 53.3 ± 7.2 years, range 45-74 years) received CU and cardiac CT angiography (CTA) including calcium scoring (CS). Results of CU and CTA were classified binary: 1. Absence of atherosclerosis and 2. Presence of atherosclerosis. The extent of atherosclerosis was not primary end point of the study. Mean PROCAM score was 2.3% (SD 2.2, range 0.44%-12.34%). One person had to be excluded from analysis (one missing CT-scan). From the remaining 48 marathon runners, 17 (35.4%) had carotid atherosclerosis and 22 (45.8%) coronary atherosclerosis. Atherosclerosis in either exam was diagnosed in 27/48 (56.3%) marathon runners. Diagnostic accuracy of CU to predict coronary atherosclerosis was: sensitivity 54.55% (95% CI 32.2-75.6), specificity 80.8% (CI 60.6-93.4), positive predictive value 70.6 (CI 44.1-89.9), negative predictive value 67.7 (CI 48.6-83.3) with a positive likelihood ratio of 2.84 (CI 1.18-6.82) and a negative likelihood ratio of 0.56 (CI 0.34-0.92). Coronary and/or carotid atherosclerosis can be detected in more than 50% of male marathon runners aged older than 45 years. The diagnostic value of carotid ultrasound to predict coronary atherosclerosis is low but higher than the accuracy of rest- or stress-ECG. As outcome studies in sportsmen are still missing, the routine evaluation of the carotid arteries by ultrasound or even cardiac CT cannot be recommended at present. Furthermore, the incidence of atherosclerosis by our method in normal population is not known.


Assuntos
Doenças das Artérias Carótidas/diagnóstico , Doença da Artéria Coronariana/diagnóstico , Corrida , Doenças Assintomáticas , Atletas , Artérias Carótidas/diagnóstico por imagem , Angiografia Coronária , Humanos , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X , Ultrassonografia
2.
Acta Radiol ; 56(2): 143-51, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24523361

RESUMO

BACKGROUND: Three-vessel coronary artery disease (CAD) comes along with globally reduced myocardial perfusion potentially restricting the demarcation of regional hypoperfusion in stress perfusion cardiac magnetic resonance imaging (MRI). PURPOSE: To evaluate whether stress perfusion cardiac MRI is capable of detecting myocardial hypoperfusion in patients with 3-vessel CAD reliably. MATERIAL AND METHODS: Two hundred and five patients with symptoms of CAD were included. The examination protocol comprised imaging of myocardial perfusion at stress (0.14 mg/kg/min adenosine for 4 min) using a 2D saturation recovery gradient echo sequence after administration of gadobutrol (0.1 mmol/kg body weight). Perfusion sequences were assessed qualitatively by two experienced observers. Coronary angiography served as standard of reference. RESULTS: Sensitivity and specificity for hemodynamically relevant stenoses in patients with 0-, 1-, 2-, 3-vessel coronary artery disease were 100%/91%, 91%/73%, 90%/71%, 92%/64%; positive/negative predictive value, 67%/100%, 91%/73%, 83%/81%, 93%/58%; diagnostic accuracy, 93%/87%/83%/87%, respectively. The negative predictive value in patients with 3-vessel CAD was lower than in patients with 0- and 2-vessel CAD and the specificity lower than in patients with no CAD whereas the positive predictive value was higher than in patients with no CAD. The other proportions did not differ significantly between the groups. CONCLUSION: The diagnostic value of stress perfusion cardiac MRI in patients with 3-vessel CAD is comparable to results in patients with 1- or 2-vessel CAD. In the rare event that stress perfusion images do not depict regional hypoperfusion in patients with severe 3-vessel CAD, myocardial ischemia could be identified by reduced semi-quantitative perfusion parameters.


Assuntos
Artefatos , Doença da Artéria Coronariana/diagnóstico , Teste de Esforço , Angiografia por Ressonância Magnética/métodos , Imagem de Perfusão do Miocárdio/métodos , Compostos Organometálicos , Meios de Contraste , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Índice de Gravidade de Doença
3.
Z Rheumatol ; 74(10): 878-85, 2015 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-26589201

RESUMO

BACKGROUND: Combined MRI/PET enables the acquisition of a variety of imaging parameters during one examination, including anatomical and functional information such as perfusion, diffusion, and metabolism. OBJECTIVE: The present article summarizes these methods and their applications in multiparametric imaging via MRI/PET. RESULTS: Numerous studies have shown that the combination of these parameters can improve diagnostic accuracy for many applications, including the imaging of oncological, neurological, and inflammatory conditions. Because of the amount and the complexity of the acquired multiparametric data, there is a need for advanced analysis tools, such as methods of parameter selection and data classification. DISCUSSION: Currently, the clinical application of this process still has limitations. On the one hand, software for the fast calculation and standardized evaluation of the imaging data acquired is still lacking. On the other hand, there are deficiencies when comparing the results because of a lack of standardization of the assessment and diagnostic procedure.


Assuntos
Aumento da Imagem/métodos , Angiografia por Ressonância Magnética/métodos , Imagem Multimodal/métodos , Tomografia por Emissão de Pósitrons/métodos , Técnica de Subtração , Vasculite/diagnóstico , Humanos , Interpretação de Imagem Assistida por Computador/métodos , Compostos Radiofarmacêuticos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
4.
Eur Radiol ; 24(3): 770-9, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24306426

RESUMO

OBJECTIVES: To determine the diagnostic benefit of volume perfusion computed tomography (VPCT) at end of treatment for response assessment in lymphoma patients. METHODS: Seventy-five patients with different lymphoma subtypes were included: 50/75 patients had residual masses at end of treatment, 26/50 patients underwent VPCT at baseline and at end of treatment, and 24/50 patients only had end-of-treatment VPCTs. We evaluated the size of the main lymphoma mass, its blood flow (BF), blood volume (BV) and k-trans, calculated ratios (baseline and end of treatment) as well as sensitivity/specificity/negative (NPV)/positive predictive values (PPV). For VPCT at end of treatment, a cutoff threshold between responders and non-responders was calculated. RESULTS: For patients undergoing VPCT at baseline and end of treatment, reduction in size, BF, BV and k-trans was significant (P < 0.001). Identification of non-response was reached at: <53% reduction in size (sensitivity/specificity/accuracy/PPV/NPV of 88.89%/62.5%/80.77%/84.21%/71.43%), <15% reduction of BF (sensitivity/specificity/accuracy/PPV/NPV of 100%/37.5%/80.77%/0.26%/100%), or <45% reduction of k-trans (sensitivity/specificity/accuracy/PPV/NPV of 88.89%/75%/84.62%/88.89%/75%). In the subgroup undergoing VPCT at end of treatment, BF >18.51 ml/100 ml indicated non-responsiveness (sensitivity 92.86%, specificity 72.73%, accuracy 84%, PPV 81.25%, NPV 88.89%). CONCLUSIONS: VPCT seems adequate for assessment of lymphoma response at end of treatment. The degree of residual lymphoma perfusion at end of treatment helps to identify patients likely to remain in remission 1 year after completion of therapy. KEY POINTS: • Volume perfusion computed tomography (VPCT) offers measurements for assessing tumour response. • Perfusion parameter changes measured by VPCT correlate with antitumour therapy response. • In lymphoma, baseline and end-of-treatment perfusion parameter ratios can predict response. • Perfusion measurements after treatment identify patients likely to remain in remission.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Tomografia Computadorizada de Feixe Cônico , Monitoramento de Medicamentos/métodos , Linfoma/diagnóstico por imagem , Linfoma/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Volume Sanguíneo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasia Residual , Imagem de Perfusão , Estudos Prospectivos , Terapia de Salvação/métodos , Sensibilidade e Especificidade
5.
Eur Radiol ; 24(7): 1621-7, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24737529

RESUMO

OBJECTIVES: The aim of this study was to evaluate the accuracy of preoperative magnetic resonance imaging (MRI) in the diagnosis of malformations associated with Mayer-Rokitansky-Küster-Hauser (MRKH) syndrome and identification of uterine endometrium to optimise the clinical management. METHODS: We retrospectively reviewed 214 consecutive MRKH patients, mean age 19 years, who underwent laparoscopy-assisted neovagina creation. A total of 115 patients (53.7%) met the inclusion criterion of sufficient preoperative MRI. In 110 of them (95.7%), MRI findings were correlated with laparoscopy and associated malformations. In 39 cases (35.5%) uterine rudiments were removed and analysed histopathologically. RESULTS: Ten per cent (11/110) of the patients showed complete uterine agenesis. The others presented with either unilateral (n = 16; 14.5%) or bilateral (n = 83; 75.5%) uterine rudiments. MRI detection of uterine rudiments agreed in 78.2% (86/110) with laparoscopy. In 85.4% of the removed rudiments, MRI could correctly diagnose the existence of the endometrium. Compared to laparoscopy, MRI could exactly detect ovaries in 97.3% (107/110). Renal or ureteral malformations were seen in 32 cases (27.8%). In 83% of unilateral renal agenesis and unilateral rudiment, the latter was located at the side of the kidney. CONCLUSIONS: MRI is useful for preoperative detection of MRKH-associated malformations and assessment of the endometrium to further optimise MRKH patient treatment. KEY POINTS: • Pelvic MRI is useful for preoperative detection of MRKH-associated malformations. • MRI can diagnose uterine endometrium in MRKH patients with high precision. • Preoperative MRI can optimise clinical management of patients with MRKH syndrome.


Assuntos
Transtornos 46, XX do Desenvolvimento Sexual/diagnóstico , Anormalidades Congênitas/diagnóstico , Imagem Ecoplanar/métodos , Endométrio/patologia , Ductos Paramesonéfricos/anormalidades , Vagina/anormalidades , Adolescente , Adulto , Diagnóstico Diferencial , Feminino , Seguimentos , Procedimentos Cirúrgicos em Ginecologia/métodos , Humanos , Laparoscopia , Período Pré-Operatório , Estudos Retrospectivos , Vagina/cirurgia , Adulto Jovem
6.
Clin Radiol ; 69(7): 695-702, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24679372

RESUMO

AIM: To evaluate whether another contrast-enhanced (CE) magnetic resonance imaging (MRI) examination 24-48 h after MRI-guided vacuum-assisted breast biopsy (MRI-VAB) can reduce the rate of false-negative cases. MATERIALS AND METHODS: The study included 252 patients who underwent MRI-VAB for the clarification of 299 lesions. The success of MRI-VAB was assessed at interventional MRI and another CE MRI 24-48 h after the intervention. In cases of successful MRI-VAB (complete or partial lesion removal) and benign histological results, follow-up breast MRI was performed. In cases of unsuccessful biopsy (unchanged lesion), tissue sampling was repeated. False-negative cases were calculated to assess the diagnostic value of MRI follow-up within 2 days after intervention. RESULTS: Ninety-eight malignant (32.8%) and 201 (67.2%) benign lesions were diagnosed using MRI-VAB. At immediate unenhanced control MRI, all lesions were assessed as successfully biopsied. In 18 benign cases (6%), CE MRI after 24-48 h showed an unsuccessful intervention. Further tissue sampling revealed another 13 cancers in these patients. This results in a false-negative rate of 11.7%. Follow-up MRI of the benign lesions presented no further malignancy. CONCLUSIONS: MRI-VAB with immediate unenhanced control offers a success rate of 94%. The rate of false-negative biopsies (11.7%) could be reduced to zero by using short-term follow-up MRI. Therefore, a further CE breast MRI 24-48 h after benign MRI-VAB to eliminate missed cancers is recommended.


Assuntos
Doenças Mamárias/patologia , Mama/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia por Agulha/métodos , Doenças Mamárias/diagnóstico por imagem , Reações Falso-Negativas , Feminino , Seguimentos , Humanos , Biópsia Guiada por Imagem/métodos , Imagem por Ressonância Magnética Intervencionista/métodos , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Tempo , Ultrassonografia , Vácuo
7.
Urol Int ; 92(3): 294-9, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24296943

RESUMO

OBJECTIVE: To evaluate the accuracy of high-spatial resolution T2-weighted endorectal magnetic resonance imaging (eMRI) for detection and pattern depiction of seminal vesicle invasion (SVI) in patients with prostate cancer (PCa). METHODS: 376 patients were included who underwent eMRI for staging before radical open prostatectomy at 1.5 T with an endorectal coil. Statistical accuracy for detection of SVI was calculated. MR images of patients with SVI were further evaluated by two radiologists according to the classification by Wheeler and Ohori. RESULTS: In the cohort, 35 patients had SVI after histopathological evaluation of the prostatectomy specimen (stage pT3b). Sensitivity and specificity for detection of SVI were 48.6 and 97.7%, respectively. Negative and positive predictive values and overall accuracy were 94.9, 68.0, and 93.1%, respectively. Infiltration pattern analysis showed that type I invasion was most common with 48.6 followed by type IIa (31.4%) and IIb (20%). Type III was not present. There was no statistical significant difference between the three groups regarding Gleason score, age, and prostate-specific antigen level. CONCLUSIONS: eMRI with high-spatial resolution T2-weighted imaging is accurate for assessment of SVI. Depiction of different infiltration types of SVI is feasible. By adding information about the extent of SVI, diagnostic reporting and risk stratification could be improved.


Assuntos
Imageamento por Ressonância Magnética , Neoplasias da Próstata/patologia , Glândulas Seminais/patologia , Adulto , Idoso , Humanos , Calicreínas/sangue , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Invasividade Neoplásica , Estadiamento de Neoplasias , Valor Preditivo dos Testes , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/sangue , Estudos Retrospectivos , Medição de Risco , Fatores de Risco
8.
Eur Radiol ; 23(1): 212-21, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22843057

RESUMO

OBJECTIVE: To explore the role of whole-body magnetic resonance imaging (MRI) in detecting musculoskeletal involvement in patients with systemic scleroderma and musculoskeletal symptoms. METHODS: Eighteen consecutive patients (8 men, 10 women) with systemic scleroderma (median age 46 years) presenting with musculoskeletal complaints underwent whole-body MRI at 1.5 T. Images were evaluated for abnormal signal intensity and/or thickening of subcutaneous fatty tissue septa, muscular fasciae, intramuscular perifascial septa, muscle signal intensity and articular or tendon sheath synovial abnormalities on STIR and post-gadolinium scans. Additionally, C-reactive protein, creatinine kinase and the modified Rodnan skin score were determined. RESULTS: MRI indicated evidence of fasciitis, articular synovial inflammation, and subcutaneous thickening in 16 (89 %) patients. MRI findings were compatible with myopathy or myositis in 14 (78 %) patients, tenosynovitis in 11 (61 %) patients and enthesitis in 10 (56 %) patients. Typically, these manifestations were distributed symmetrically and mostly generalised. We only found few correlations with modified Rodnan skin score, C-reactive protein and creatinine kinase. CONCLUSION: In patients with systemic scleroderma experiencing musculoskeletal symptoms, whole-body MRI is able to detect involvement of muscles, fasciae, joints and entheses more confidently compared with clinical and laboratory parameters.


Assuntos
Imageamento por Ressonância Magnética/métodos , Sistema Musculoesquelético/patologia , Escleroderma Sistêmico/patologia , Imagem Corporal Total/métodos , Adulto , Meios de Contraste , Feminino , Gadolínio DTPA , Humanos , Masculino , Pessoa de Meia-Idade , Compostos Organometálicos
9.
Eur Radiol ; 23(2): 588-95, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22898936

RESUMO

OBJECTIVES: To evaluate stent lumen assessment of various commonly used and newly developed stents for the superficial femoral artery (SFA) using MR angiography (MRA) at 1.5 and 3 T. METHODS: Eleven nitinol stents and one cobalt-chromium stent were compared regarding stent lumen visualisation using a common three-dimensional MRA sequence. Maximum visible stent lumen width and contrast ratio were analysed in three representative slices for each stent type. A scoring system for lumen visualisation was applied. RESULTS: Nitinol stents showed significantly better performance than the cobalt chromium stent (P < 0.05) at 1.5 and 3 T. Maximum visible stent lumen ranged between 43.4 and 95.5 %, contrast ratio between 7.2 and 110.6 %. Regarding both field strengths, seven of the nitinol stents were classified as "suitable". Three nitinol stents were "limited", and one nitinol stent and the cobalt chromium stent were "not suitable". CONCLUSIONS: Intraluminal loss of signal and artefacts of most of the SFA stents do not markedly limit assessment of stent lumen by MRA at 1.5 and 3 T. MRA can thus be considered a valid technique for detection of relevant in-stent restenosis. Applied field strength does not strongly influence stent lumen assessment in general, but proper choice of field strength might be helpful.


Assuntos
Ligas , Cobalto , Imageamento Tridimensional , Angiografia por Ressonância Magnética/métodos , Stents , Meios de Contraste , Feminino , Artéria Femoral , Humanos , Técnicas In Vitro , Masculino , Teste de Materiais , Imagens de Fantasmas , Desenho de Prótese , Estatísticas não Paramétricas
10.
Neuroradiology ; 55(4): 423-30, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23223824

RESUMO

INTRODUCTION: High-pitch CT angiography (CTA) is a recent innovation that allows significant shortening of scan time with volume coverage of 43 mm per second. The aim of our study was to assess this technique in CTA of the head and neck. METHODS: CTA of supra-aortic arteries was performed in 50 patients using two acquisition protocols: conventional single-source 64-slice (pitch 1.2) and high-pitch dual-source 128-slice CT (pitch 3.2). Subjective and objective image quality of supra-aortic vessel ostia as well as intra- and extra-cranial segments was retrospectively assessed by blinded readers and radiation dose compared between the two protocols. RESULTS: Conventional and high-pitch CTA achieved comparable signal-to-noise ratios in arterial (54.3 ± 16.5 versus 57.3 ± 14.8; p = 0.50) and venous segments (15.8 ± 6.7 versus 18.9 ± 8.9; p = 0.21). High-pitch scanning was, however, associated with sharper delineation of vessel contours and image quality significantly improved at the level of supra-aortic vessel ostia (p < 0.0001) as well as along the brachiocephalic trunk (p < 0.0001), the subclavian arteries (p < 0.0001), proximal common carotid arteries (p = 0.01), and vertebral V1 segments (p < 0.0001). Using the high-pitch mode, the dose-length product was reduced by about 35% (218.2 ± 30 versus 141.8 ± 20 mGy × cm). CONCLUSIONS: Due to elimination of transmitted cardiac motion, high-pitch CTA of the neck improves image quality in the proximity of the aortic arch while significantly lowering radiation dose. The technique thus qualifies as a promising alternative to conventional spiral CTA and may be particularly useful for identification of ostial stenosis.


Assuntos
Angiografia/métodos , Aorta Torácica/diagnóstico por imagem , Doses de Radiação , Intensificação de Imagem Radiográfica/métodos , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Imagem Radiográfica a Partir de Emissão de Duplo Fóton/métodos , Tomografia Computadorizada por Raios X/métodos , Idoso , Algoritmos , Carga Corporal (Radioterapia) , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
11.
Acta Radiol ; 54(8): 895-903, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23828946

RESUMO

Cardiac masses are challenging for non-invasive diagnostic procedures and therapy, respectively. In tumor patients differentiation between primary or secondary cardiac neoplasm and thrombus is a frequent and knowingly difficult task to manage. To avoid complex and unnecessary surgical diagnostic procedures non-invasive methods are in favor. For initiation of adequate therapy and evaluation of prognosis, however, early and reliable diagnosis is mandatory. So far, echocardiography and magnetic resonance imaging represent the mainstay for cardiac imaging diagnosis. Recently, the new technique of CT-based tumor volume perfusion (VPCT) measurement has advanced to a potent, reliable, and easy to perform alternative for cardiac imaging. The purpose of this study was to review the existing spectrum of diagnostic modalities for characterization of cardiac masses in an oncologic patient cohort with emphasis on their strengths and limitations and to present the benefit from using the novel technique called VPCT for this purpose.


Assuntos
Neoplasias Cardíacas/diagnóstico por imagem , Achados Incidentais , Imagem de Perfusão/métodos , Tomografia Computadorizada por Raios X/métodos , Carga Tumoral , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes
12.
Radiologe ; 53(1): 45-53, 2013 Jan.
Artigo em Alemão | MEDLINE | ID: mdl-23160570

RESUMO

CLINICAL/METHODICAL ISSUE: Besides ischemic heart disease cardiomyopathies are common causes of heart failure and sudden cardiac death. STANDARD RADIOLOGICAL METHODS: The diagnostic spectrum in cardiomyopathies comprises non-invasive and invasive examination techniques. METHODICAL INNOVATIONS: The exact verification of certain cardiomyopathies necessitates knowledge of the latest classification of cardiomyopathies as well as dedicated examination protocols. PERFORMANCE: Modern imaging modalities, such as echocardiography and cardiac magnetic resonance imaging (MRI) have emerged as useful imaging tools in the investigation of patients suspected of having many different types of cardiomyopathies. ACHIEVEMENTS: Based on a better understanding of the underlying pathophysiology several diagnostic criteria have been defined using cardiac MRI. In particular there is an increasing importance of cardiac MRI in the description of patients with restrictive and unclassified cardiomyopathies. PRACTICAL RECOMMENDATIONS: Echocardiography still remains the modality of choice in the diagnostics of unclear left ventricular heart failure. Further diagnostic work-up should include cardiac MRI in case of any lack of clarity.


Assuntos
Cardiomiopatias/diagnóstico , Aumento da Imagem/métodos , Imagem Cinética por Ressonância Magnética/métodos , Miocárdio/patologia , Humanos
13.
Radiologe ; 53(8): 669-75, 2013 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-23949435

RESUMO

Combined magnetic resonance imaging-positron emission tomography (MR/PET) enables acquisition of a variety of imaging parameters during a single examination including anatomical as well as functional information, such as perfusion, diffusion and metabolism. Numerous studies have shown that the combination of these parameters can improve the diagnostic accuracy for many applications especially in oncological imaging. Due to the amount and the complexity of the acquired multiparametric data there is a need for advanced analytical tools, such as methods of parameter selection and data classification. The present article summarizes these methods and their applications in multiparametric imaging via MR/PET.


Assuntos
Aumento da Imagem/métodos , Imageamento por Ressonância Magnética/tendências , Imagem Multimodal/tendências , Tomografia por Emissão de Pósitrons/tendências
14.
Diabetologia ; 55(7): 2054-8, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22526613

RESUMO

AIMS/HYPOTHESIS: Microalbuminuria represents an established surrogate marker of early diabetic nephropathy and glomerular microangiopathy. Increasing evidence is emerging of a role of perivascular adipose tissue (PVAT) as an important link between obesity, insulin resistance and both macro- and microangiopathy. It is not known whether perivascular renal sinus fat (RSF) has an impact on microalbuminuria in the prediabetic stage. We investigated whether RSF quantified by MRI is associated with microalbuminuria before or after exercise. METHODS: Non-diabetic individuals at increased risk of type 2 diabetes were recruited into the Tübingen Lifestyle Intervention Program (TULIP); 146 participants took part in the analysis. RSF was measured in axial MRI sections at the level of the renal artery. Urine was collected before and after exercise stress testing. RESULTS: Participants (age 47 ± 12 years; mean ± SD) reached a mean exercise load of 176 ± 49 W, with a mean arterial peak pressure (MAPP) of 112 ± 14 mmHg. After adjusting for sex, age, visceral adipose tissue (VAT) and MAPP during exercise, RSF was significantly associated with postexercise albumin/creatinine ratio (ACR; p = 0.006). No association between RSF and baseline BP could be observed after adjusting for confounders (p = 0.26), and there was no association between RSF and baseline ACR either (p = 0.2). CONCLUSIONS: RSF is associated with exercise-induced albuminuria independently of sex, age, VAT and MAPP in a non-diabetic cohort at diabetic risk. We conclude that PVAT in the renal sinus may play a role in the pathogenesis of microalbuminuria.


Assuntos
Albuminúria/urina , Glicemia/metabolismo , Creatinina/urina , Diabetes Mellitus Tipo 2/complicações , Nefropatias Diabéticas/urina , Exercício Físico , Nefropatias/urina , Albuminúria/etiologia , Albuminúria/fisiopatologia , Pressão Sanguínea , Diabetes Mellitus Tipo 2/urina , Nefropatias Diabéticas/etiologia , Nefropatias Diabéticas/fisiopatologia , Teste de Esforço , Feminino , Humanos , Gordura Intra-Abdominal/metabolismo , Nefropatias/fisiopatologia , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes
15.
Eur Radiol ; 22(4): 812-20, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22057214

RESUMO

OBJECTIVE: To assess parenchymal bolus-triggering in terms of liver enhancement, lesion-to-liver conspicuity and inter-image variability across serial follow-up MDCTs. METHODS: We reviewed MDCTs of 50 patients with hepatic metastases who had a baseline CT and two follow-up examinations. In 25 consecutive patients CT data acquisition was initiated by liver parenchyma triggering at a 50-HU enhancement threshold. In a matched control group, imaging was performed with an empirical delay of 65 s. CT attenuation values were assessed in vessels, liver parenchyma and metastasis. Target lesions were classified according to five enhancement patterns. RESULTS: Compared with the control group, liver enhancement was significantly higher with parenchyma triggering (59.8 ± 7.6 HU vs. 48.8 ± 11.2 HU, P = 0.0002). The same was true for conspicuity (liver parenchyma - lesion attenuation) of hypo-enhancing lesions (72.2 ± 15.9 HU vs. 52.7 ± 19.4 HU, P = 0.0006). Liver triggering was associated with reduced variability for liver enhancement among different patients (P = 0.035) and across serial follow-up examinations in individual patients (P < 0.0001). The number of patients presenting with uniform lesion enhancement pattern across serial examinations was significantly higher in the triggered group (20 vs. 11; P = 0.018). CONCLUSION: Liver parenchyma triggering provides superior lesion conspicuity and improves standardisation of image quality across follow-up examinations with greater uniformity of enhancement patterns. KEY POINTS: Liver parenchyma tracking improves liver enhancement and lesion-to-liver conspicuity in abdominal CT. In serial CT studies this technique reduces variability of conspicuity and enhancement patterns. Higher liver-to-lesion conspicuity is a prerequisite for reliable detection of liver lesions. Stabilisation of enhancement permits more accurate follow-up of oncology patients.


Assuntos
Algoritmos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/secundário , Fígado/diagnóstico por imagem , Intensificação de Imagem Radiográfica/métodos , Tomografia Computadorizada por Raios X/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valores de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Tomografia Computadorizada por Raios X/normas , Estados Unidos
16.
Abdom Imaging ; 37(1): 20-8, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22002195

RESUMO

Over the last few decades it has been shown that novel technologies and technological progress rapidly change the working environment of radiologists and nuclear medicine physicians. Thus, new possibilities, e.g., in tumor staging and therapy monitoring, but also new challenges arise. Recently, it could be shown that the integration of magnetic resonance imaging (MRI) and positron emission tomography (PET) is technically possible. The evolvement of new dedicated hybrid MR/PET systems for whole-body imaging in humans offers new potential in multimodal imaging. Especially simultaneous measurement of PET and MRI datasets allows for insights in metabolic and functional processes, particularly in oncologic demands, but also in cardiovascular and cerebral imaging. In this work-in-progress review article, a technical summary including the method-inherent challenges are given. Furthermore, possible clinical applications and research interests are addressed.


Assuntos
Abdome/diagnóstico por imagem , Abdome/patologia , Imageamento por Ressonância Magnética , Tomografia por Emissão de Pósitrons , Imagem Corporal Total , Humanos
17.
Abdom Imaging ; 37(2): 244-51, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21479607

RESUMO

OBJECTIVES: To assess the feasibility of a comprehensive MRI protocol using intrabiliary contrast medium (gadolinium-EOB-DTPA) for evaluation of living liver donors. MATERIAL AND METHODS: In this prospective study, 30 donor candidates for living-related liver transplantation (17 men; 13 women, mean age 37 ± 10.9 years) underwent MRI including MR-angiography (MRA) as well as a conventional T2-weighted MR-cholangiography (MRC) and a contrast-enhanced sequence for depiction of the biliary structures. MRC and MRA images were evaluated for quality on a four-point-scale (score of 0 indicated poor and a score of 3, excellent image quality). Anatomic variants of the arterial, venous, portal venous, and biliary structures were identified. RESULTS: Image quality was diagnostic in all examinations except for 4 of 30 MRA data sets. Intrahepatic biliary structures, especially with regard to the intrahepatic bile ducts of 2nd and 3rd order could be identified with significantly increased image quality than in conventional T2-weighted MRC sequences (P = 0.005 and P = 0.035). A high percentage rate of anatomic variants regarding the biliary, arterial, venous, and portal venous anatomy was found. CONCLUSION: This protocol allows the evaluation of liver donors especially with regard to the biliary structures. However, the depiction of the arterial anatomy requires further technical developments.


Assuntos
Transplante de Fígado , Fígado/anatomia & histologia , Doadores Vivos , Imageamento por Ressonância Magnética/métodos , Adulto , Colangiopancreatografia por Ressonância Magnética , Meios de Contraste , Estudos de Viabilidade , Feminino , Gadolínio DTPA , Humanos , Interpretação de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Estatísticas não Paramétricas
18.
Eur Radiol ; 21(5): 1050-7, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21046404

RESUMO

OBJECTIVES: To test the hypothesis that MR imaging guided triamcinolone acetonide injection into the sacroiliac joints of children with enthesitis-related arthritis is feasible, accurate and safe; and effectively reduces sacroiliac inflammation and disease progression. METHODS: A retrospective analysis of 14 children (6/14 [43%] female, 8/14 (57%) male; mean age, 13.2 years; range, 6-16 years) who received MR imaging guided sacroiliac joint injections at 0.2 Tesla or 1.5 Tesla for enthesitis-related arthritis and acute sacroilitis refractory to medical therapy was performed. 20 mg triamcinolone acetonide were injected. Assessed were intra-articular drug delivery; image quality, duration, and complications. Success of therapy was defined by change of sacroiliac inflammation. Remission time and erosions were assessed by follow-up MRI (range, 10-22 months). RESULTS: Twenty four procedures resulted in intra-articular injection. Image quality was sufficient. No complications occurred. Procedure time was 40 min. Sedation time was 22 min. Success of therapy was achieved in 11/14 (79%) children. Sacroiliac inflammation decreased significantly (-59%). Median remission time was 13.7 months. No erosions occurred. CONCLUSIONS: MR imaging guided steroid injection of the sacroiliac joints is feasible, accurate, and safe and can effectively reduce sacroiliac inflammatory activity and may therefore aid in the prevention of disease progression.


Assuntos
Artrite/patologia , Imageamento por Ressonância Magnética/métodos , Articulação Sacroilíaca/patologia , Esteroides/uso terapêutico , Adolescente , Artrite/tratamento farmacológico , Artrite/etiologia , Criança , Estudos de Coortes , Progressão da Doença , Feminino , Humanos , Inflamação , Injeções Intra-Articulares , Masculino , Estudos Retrospectivos , Articulação Sacroilíaca/efeitos dos fármacos , Resultado do Tratamento
19.
Acta Radiol ; 52(8): 881-8, 2011 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-21878551

RESUMO

Imaging modalities used in the diagnosis of multiple myeloma have evolved and most of them are also suitable for either early or mid-term monitoring of response to novel antimyeloma therapy. This pictorial essay focuses on modern imaging techniques for diagnosis and follow-up of patients with multiple myeloma in order to highlight their individual strengths and limitations. Also, the impact of recently established modern pharmaceutical therapy, like anti-angiogenic medication, on the tumor is addressed.


Assuntos
Diagnóstico por Imagem/tendências , Mieloma Múltiplo/diagnóstico , Biomarcadores Tumorais/análise , Humanos , Imageamento por Ressonância Magnética/tendências , Mieloma Múltiplo/terapia , Tomografia por Emissão de Pósitrons/tendências , Tomografia Computadorizada por Raios X/tendências , Ultrassonografia/tendências , Imagem Corporal Total
20.
J Cardiovasc Surg (Torino) ; 51(2): 203-12, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20354490

RESUMO

The study was designed as a feasibility trial to evaluate the use of GP IIb/IIIa blockade in connection with drug eluting stents, bare stents and PTA only. Sixty patients with current ulcers were randomly assigned to receive abciximab plus a sirolimus coated stent (N.=14), abciximab plus a bare stent (N.=16), abciximab plus PTA (N.=14) and PTA alone (N.=19). Angiographic control was performed at two and six months. Recanalization was successful in all cases. Two month restenosis rate was 9%, 45.5%, 67% and 46%. At six month follow-up restenosis rate was 9%, 67%, 75% and 58%, respectively; 14% of all patients had major amputations within six months. Adjunctive administration of abciximab during peripheral arterial intervention below the knee was found to be safe. Sirolimus coated stent administration was followed by a higher patency rate.


Assuntos
Angioplastia com Balão/instrumentação , Anticorpos Monoclonais/uso terapêutico , Fármacos Cardiovasculares/administração & dosagem , Stents Farmacológicos , Fragmentos Fab das Imunoglobulinas/uso terapêutico , Úlcera da Perna/terapia , Extremidade Inferior/irrigação sanguínea , Metais , Inibidores da Agregação Plaquetária/uso terapêutico , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/antagonistas & inibidores , Sirolimo/administração & dosagem , Stents , Abciximab , Idoso , Amputação Cirúrgica , Angioplastia com Balão/efeitos adversos , Anticorpos Monoclonais/efeitos adversos , Estudos de Viabilidade , Feminino , Humanos , Fragmentos Fab das Imunoglobulinas/efeitos adversos , Úlcera da Perna/diagnóstico por imagem , Úlcera da Perna/tratamento farmacológico , Úlcera da Perna/fisiopatologia , Salvamento de Membro , Masculino , Inibidores da Agregação Plaquetária/efeitos adversos , Estudos Prospectivos , Desenho de Prótese , Radiografia , Recidiva , Fatores de Tempo , Resultado do Tratamento , Grau de Desobstrução Vascular
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