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1.
BMC Gastroenterol ; 22(1): 82, 2022 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-35216547

RESUMO

BACKGROUND: In patients with severe polycystic liver disease (PLD), there is a need for new treatments. Estrogens and possibly other female sex hormones stimulate growth in PLD. In some patients, liver volume decreases after menopause. Female sex hormones could therefore be a target for therapy. The AGAINST-PLD study will examine the efficacy of the GnRH agonist leuprorelin, which blocks the production of estrogen and other sex hormones, to reduce liver growth in PLD. METHODS: The AGAINST-PLD study is an investigator-driven, multicenter, randomized controlled trial. Institutional review board (IRB) approval was received at the University Medical Center of Groningen and will be collected in other sites before opening these sites. Thirty-six female, pre-menopausal patients, with a very large liver volume for age (upper 10% of the PLD population) and ongoing liver growth despite current treatment options will be randomized to direct start of leuprorelin or to 18 months standard of care and delayed start of leuprorelin. Leuprorelin is given as 3.75 mg subcutaneously (s.c.) monthly for the first 3 months followed by 3-monthly depots of 11.25 mg s.c. The trial duration is 36 months. MRI scans to measure liver volume will be performed at screening, 6 months, 18 months, 24 months and 36 months. In addition, blood will be drawn, DEXA-scans will be performed and questionnaires will be collected. This design enables comparison between patients on study treatment and standard of care (first 18 months) and within patients before and during treatment (whole trial). Main outcome is annualized liver growth rate compared between standard of care and study treatment. Secondary outcomes are PLD disease severity, change in liver growth within individuals and (serious) adverse events. The study is designed as a prospective open-label study with blinded endpoint assessment (PROBE). DISCUSSION: In this trial, we combined the expertise of hepatologist, nephrologists and gynecologists to study the effect of leuprorelin on liver growth in PLD. In this way, we hope to stop liver growth, reduce symptoms and reduce the need for liver transplantation in severe PLD. Trial registration Eudra CT number 2020-005949-16, registered at 15 Dec 2020. https://www.clinicaltrialsregister.eu/ctr-search/search?query=2020-005949-16 .


Assuntos
Leuprolida , Hepatopatias , Feminino , Humanos , Cistos , Leuprolida/uso terapêutico , Hepatopatias/tratamento farmacológico , Estudos Multicêntricos como Assunto , Estudos Prospectivos , Ensaios Clínicos Controlados Aleatórios como Assunto
2.
Eur Radiol ; 26(3): 683-92, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26162576

RESUMO

OBJECTIVES: Renal blood flow (RBF) has been shown to predict disease progression in autosomal dominant polycystic kidney disease (ADPKD). We investigated the feasibility and accuracy of phase-contrast RBF by MRI (RBFMRI) in ADPKD patients with a wide range of estimated glomerular filtration rate (eGFR) values. METHODS: First, we validated RBFMRI measurement using phantoms simulating renal artery hemodynamics. Thereafter, we investigated in a test-set of 21 patients intra- and inter-observer coefficient of variation of RBFMRI. After validation, we measured RBFMRI in a cohort of 91 patients and compared the variability explained by characteristics indicative for disease severity for RBFMRI and RBF measured by continuous hippuran infusion. RESULTS: The correlation in flow measurement using phantoms by phase-contrast MRI was high and fluid collection was high (CCC=0.969). Technical problems that precluded RBFMRI measurement occurred predominantly in patients with a lower eGFR (34% vs. 16%). In subjects with higher eGFRs, variability in RBF explained by disease characteristics was similar for RBFMRI compared to RBFHip, whereas in subjects with lower eGFRs, this was significantly less for RBFMRI. CONCLUSIONS: Our study shows that RBF can be measured accurately in ADPKD patients by phase-contrast, but this technique may be less feasible in subjects with a lower eGFR. KEY POINTS: Renal blood flow (RBF) can be accurately measured by phase-contrast MRI in ADPKD patients. RBF measured by phase-contrast is associated with ADPKD disease severity. RBF measurement by phase-contrast MRI may be less feasible in patients with an impaired eGFR.


Assuntos
Imageamento por Ressonância Magnética/métodos , Rim Policístico Autossômico Dominante/fisiopatologia , Circulação Renal/fisiologia , Adulto , Pressão Sanguínea/fisiologia , Estudos de Coortes , Meios de Contraste , Progressão da Doença , Estudos de Viabilidade , Feminino , Taxa de Filtração Glomerular/fisiologia , Hemodinâmica/fisiologia , Humanos , Radioisótopos do Iodo , Ácido Iodoipúrico , Masculino , Pessoa de Meia-Idade , Imagens de Fantasmas , Compostos Radiofarmacêuticos , Artéria Renal/fisiologia , Reprodutibilidade dos Testes
3.
Eur Radiol ; 22(4): 915-22, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22076317

RESUMO

OBJECTIVE: To determine whether quantitative multivoxel MRS improves the accuracy of MRI in the assessment of breast lesions. METHODS: Twenty-five consecutive patients with 26 breast lesions ≥ 1 cm assessed as BI-RADS 3 or 4 with mammography underwent quantitative multivoxel MRS and contrast-enhanced MRI. The choline (Cho) concentration was calculated using the unsuppressed water signal as a concentration reference. ROC analysis established the diagnostic accuracy of MRI and MRS in the assessment of breast lesions. RESULTS: Respective Cho concentrations in 26 breast lesions re-classified by MRI as BI-RADS 2 (n = 5), 3 (n = 8), 4 (n = 5) and 5 (n = 8) were 1.16 ± 0.43 (mean ± SD), 1.43 ± 0.47, 2.98 ± 2.15 and 4.94 ± 3.10 mM. Two BI-RADS 3 lesions and all BI-RADS 4 and 5 lesions were malignant on histopathology and had Cho concentrations between 1.7 and 11.8 mM (4.03 ± 2.72 SD), which were significantly higher (P = 0.01) than that in the 11 benign lesions (0.4-1.5 mM; 1.19 ± 0.33 SD). Furthermore, Cho concentrations in the benign and malignant breast lesions in BI-RADS 3 category differed (P = 0.01). The accuracy of combined multivoxel MRS/breast MRI BI-RADS re-classification (AUC = 1.00) exceeded that of MRI alone (AUC = 0.96 ± 0.03). CONCLUSIONS: These preliminary data indicate that multivoxel MRS improves the accuracy of MRI when using a Cho concentration cut-off ≤ 1.5 mM for benign lesions. KEY POINTS: Quantitative multivoxel MR spectroscopy can improve the accuracy of contrast-enhanced breast MRI. Multivoxel-MRS can differentiate breast lesions by using the highest Cho-concentration. Multivoxel-MRS can exclude patients with benign breast lesions from further invasive diagnostic procedures.


Assuntos
Biomarcadores Tumorais/análise , Neoplasias da Mama/diagnóstico , Imageamento Tridimensional/métodos , Imageamento por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética/métodos , Adulto , Idoso , Feminino , Humanos , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
4.
Int J Cardiovasc Imaging ; 27(4): 557-62, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20882414

RESUMO

To assess the inter-observer agreement of adenosine "stress"-only visual analysis of perfusion MR images in relation to experience and reading criteria. 106 adenosine perfusion MR examinations out of 350, 46 consecutive positive examinations and 60 randomly selected negative examinations were visually analysed by three individual readers (two residents and a technician) with different levels of experience. Readings (blinded for any information) were compared with the reading of an expert radiologist. After a month the examinations were presented again (randomly) without knowledge regarding the first readings. This time readings were performed with the systematical use of reading criteria. Agreement with the expert reading was good for the most experienced resident (k = 0.88). Kappa was 0.48 for the least experienced, and 0.57 for the technician. After the second systematical reading inter-observer agreement increased to 0.9, 0.68 and 0.77 respectively. Overall kappa increased from 0.59 to 0.71. The use of reading criteria significantly improved the performance of the least experienced reader (P = 0.01). Visual analysis of adenosine "stress"-only first-pass perfusion MR images has moderate to very good agreement. Performance is experience related, but the systematic use of reading criteria significantly increased performance for the least experienced observer.


Assuntos
Adenosina , Competência Clínica , Circulação Coronária , Imageamento por Ressonância Magnética , Isquemia Miocárdica/diagnóstico , Imagem de Perfusão do Miocárdio/métodos , Vasodilatadores , Idoso , Pressão Sanguínea , Peso Corporal , Meios de Contraste , Feminino , Gadolínio DTPA , Frequência Cardíaca , Humanos , Masculino , Pessoa de Meia-Idade , Isquemia Miocárdica/fisiopatologia , Países Baixos , Variações Dependentes do Observador , Valor Preditivo dos Testes , Reprodutibilidade dos Testes
5.
Cancer Imaging ; 9: 19-28, 2009 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-19414293

RESUMO

AIM: In this feasibility study we investigated whether magnetic resonance imaging (MRI) with ultrasmall superparamagnetic iron oxide (USPIO) can be used to identify regional and distant lymph nodes, including mediastinal and celiac lymph node metastases in patients with oesophageal cancer. PATIENTS AND METHODS: Ten patients with a potentially curative resectable cancer of the oesophagus were eligible for this study. All patients included in the study had positive lymph nodes on conventional staging (including endoscopic ultrasound, computed tomography and fluorodeoxyglucose-positron emission tomography). Nine patients underwent MRI + USPIO before surgery. Results were restricted to those patients who had both MRI + USPIO and histological examination. Results were compared with conventional staging and histopathologic findings. RESULTS: One patient was excluded due to expired study time. Five out of 9 patients underwent an exploration; in 1 patient prior to surgery MRI + USPIO diagnosed liver metastases and in 3 patients an oesophageal resection was performed. USPIO uptake in mediastinal lymph nodes was seen in 6 out of 9 patients; in 3 patients non-malignant nodes were not visible. In total, 9 lymph node stations (of 6 patients) were separately analysed; 7 lymph node stations were assessed as positive (N1) on MRI+USPIO compared with 9 by conventional staging. According to histology findings, there was one false-positive and one false-negative result in MRI + USPIO. Also, conventional staging modalities had one false-positive and one false-negative result. MRI + USPIO had surplus value in one patient. Not all lymph node stations could be compared due to unforeseen explorations. No adverse effects occurred after USPIO infusion. CONCLUSION: MRI+USPIO identified the majority of mediastinal and celiac (suspect) lymph nodes in 9 patients with oesophageal cancer. MRI+USPIO could have an additional value in loco-regional staging; however, more supplementary research is needed.


Assuntos
Meios de Contraste , Neoplasias Esofágicas/patologia , Ferro , Imageamento por Ressonância Magnética/métodos , Óxidos , Idoso , Dextranos , Neoplasias Esofágicas/cirurgia , Estudos de Viabilidade , Feminino , Óxido Ferroso-Férrico , Humanos , Aumento da Imagem , Metástase Linfática , Nanopartículas de Magnetita , Masculino , Pessoa de Meia-Idade
6.
J Hepatol ; 32(6): 887-92, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10898308

RESUMO

BACKGROUND/AIMS: Altered energy status has been reported in the liver of tumour-bearing animals, but data on energy status in humans are scarce. Therefore, bioenergetics in tumour-free liver of lung cancer patients were monitored using 31P magnetic resonance spectroscopy (MRS) with infusion of L-alanine as a gluconeogenic challenge. METHODS: Twenty-one overnight-fasted lung cancer patients without liver metastases, with (CaWL) or without weight loss (CaWS), and 12 healthy control subjects (C) were studied. Hepatic energy status was monitored before and during an i.v. L-alanine infusion of 1.4-2.8 mmol/kg + 2.8 mmol x kg(-1) x h(-1) for 90 min by 31p MR spectroscopy. RESULTS: Baseline levels of ATP in WL lung cancer patients, expressed relative to total MR-detectable phosphate, were reduced (CaWL, 9.5+/-0.9% vs. CaWS, 12.6+/-0.8% and C, 12.4+/-0.8%; p<0.05) and inversely correlated with the degree of weight loss in lung cancer patients (r=-0.46, p=0.03). Pi/ATP ratios were increased (p<0.05), indicating reduced liver phosphorylation status. During L-alanine infusion, ATP levels decreased in all groups (p<0.05); in CaWL, ATP levels were lower at all time-points between 0-90 min as compared to both CaWS and C (p<0.05). Pi/ATP ratios were significantly higher after 70-90 min of L-alanine infusion in CaWL compared to CaWS and C (p<0.05). CONCLUSIONS: Hepatic ATP and phosphorylation status are reduced in WL lung cancer patients, in contrast to WS patients and healthy subjects, and continue to decrease during infusion of a gluconeogenic substrate, suggesting impaired energy regenerating capacity in these patients.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Fígado/metabolismo , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Redução de Peso , Trifosfato de Adenosina/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Alanina , Metabolismo Energético , Humanos , Espectroscopia de Ressonância Magnética , Pessoa de Meia-Idade , Concentração Osmolar , Fósforo/metabolismo , Fosforilação
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