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1.
Breast Cancer Res ; 26(1): 22, 2024 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-38317255

RESUMO

PURPOSE: One major risk factor for breast cancer is high mammographic density. It has been estimated that dense breast tissue contributes to ~ 30% of all breast cancer. Prevention targeting dense breast tissue has the potential to improve breast cancer mortality and morbidity. Anti-estrogens, which may be associated with severe side-effects, can be used for prevention of breast cancer in women with high risk of the disease per se. However, no preventive therapy targeting dense breasts is currently available. Inflammation is a hallmark of cancer. Although the biological mechanisms involved in the increased risk of cancer in dense breasts is not yet fully understood, high mammographic density has been associated with increased inflammation. We investigated whether low-dose acetylsalicylic acid (ASA) affects local breast tissue inflammation and/or structural and dynamic changes in dense breasts. METHODS: Postmenopausal women with mammographic dense breasts on their regular mammography screen were identified. A total of 53 women were randomized to receive ASA 160 mg/day or no treatment for 6 months. Magnetic resonance imaging (MRI) was performed before and after 6 months for a sophisticated and continuous measure breast density by calculating lean tissue fraction (LTF). Additionally, dynamic quantifications including tissue perfusion were performed. Microdialysis for sampling of proteins in vivo from breasts and abdominal subcutaneous fat, as a measure of systemic effects, before and after 6 months were performed. A panel of 92 inflammatory proteins were quantified in the microdialysates using proximity extension assay. RESULTS: After correction for false discovery rate, 20 of the 92 inflammatory proteins were significantly decreased in breast tissue after ASA treatment, whereas no systemic effects were detected. In the no-treatment group, protein levels were unaffected. Breast density, measured by LTF on MRI, were unaffected in both groups. ASA significantly decreased the perfusion rate. The perfusion rate correlated positively with local breast tissue concentration of VEGF. CONCLUSIONS: ASA may shape the local breast tissue microenvironment into an anti-tumorigenic state. Trials investigating the effects of low-dose ASA and risk of primary breast cancer among postmenopausal women with maintained high mammographic density are warranted. Trial registration EudraCT: 2017-000317-22.


Assuntos
Neoplasias da Mama , Feminino , Humanos , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/tratamento farmacológico , Mamografia/métodos , Densidade da Mama , Aspirina/efeitos adversos , Pós-Menopausa , Inflamação/tratamento farmacológico , Microambiente Tumoral
2.
Eur Radiol ; 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38459346

RESUMO

OBJECTIVES: To evaluate the diagnostic performance of ultrasound guided attenuation parameter (UGAP) for evaluating liver fat content with different probe forces and body positions, in relation to sex, and compared with proton density fat fraction (PDFF). METHODS: We prospectively enrolled a metabolic dysfunction-associated steatotic liver disease (MASLD) cohort that underwent UGAP and PDFF in the autumn of 2022. Mean UGAP values were obtained in supine and 30° left decubitus body position with normal 4 N and increased 30 N probe force. The diagnostic performance was evaluated by the area under the receiver operating characteristic curve (AUC). RESULTS: Among 60 individuals (mean age 52.9 years, SD 12.9; 30 men), we found the best diagnostic performance with increased probe force in 30° left decubitus position (AUC 0.90; 95% CI 0.82-0.98) with a cut-off of 0.58 dB/cm/MHz. For men, the best performance was in supine (AUC 0.91; 95% CI 0.81-1.00) with a cut-off of 0.60 dB/cm/MHz, and for women, 30° left decubitus position (AUC 0.93; 95% CI 0.83-1.00), with a cut-off 0.56 dB/cm/MHz, and increased 30 N probe force for both genders. No difference was in the mean UGAP value when altering body position. UGAP showed good to excellent intra-reproducibility (Intra-class correlation 0.872; 95% CI 0.794-0.921). CONCLUSION: UGAP provides excellent diagnostic performance to detect liver fat content in metabolic dysfunction-associated steatotic liver diseases, with good to excellent intra-reproducibility. Regardless of sex, the highest diagnostic accuracy is achieved with increased probe force with men in supine and women in 30° left decubitus position, yielding different cut-offs. CLINICAL RELEVANCE STATEMENT: The ultrasound method ultrasound-guided attenuation parameter shows excellent diagnostic accuracy and performs with good to excellent reproducibility. There is a possibility to alter body position and increase probe pressure, and different performances for men and women should be considered for the highest accuracy. KEY POINTS: • There is a possibility to alter body position when performing the ultrasound method ultrasound-guided attenuation parameter. • Increase probe pressure for the highest accuracy. • Different performances for men and women should be considered.

3.
Eur Radiol ; 2024 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-38795131

RESUMO

OBJECTIVE: In nonalcoholic fatty liver disease (NAFLD), liver fibrosis is the strongest predictor of adverse outcomes. We sought to investigate the relationship between liver fibrosis and cardiac remodeling in participants from the general population using magnetic resonance imaging (MRI), as well as explore potential mechanistic pathways by analyzing circulating cardiovascular biomarkers. METHODS: In this cross-sectional study, we prospectively included participants with type 2 diabetes and individually matched controls from the SCAPIS (Swedish CArdioPulmonary bioImage Study) cohort in Linköping, Sweden. Between November 2017 and July 2018, participants underwent MRI at 1.5 Tesla for quantification of liver proton density fat fraction (spectroscopy), liver fibrosis (stiffness from elastography), left ventricular (LV) structure and function, as well as myocardial native T1 mapping. We analyzed 278 circulating cardiovascular biomarkers using a Bayesian statistical approach. RESULTS: In total, 92 participants were enrolled (mean age 59.5 ± 4.6 years, 32 women). The mean liver stiffness was 2.1 ± 0.4 kPa. 53 participants displayed hepatic steatosis. LV concentricity increased across quartiles of liver stiffness. Neither liver fat nor liver stiffness displayed any relationships to myocardial tissue characteristics (native T1). In a regression analysis, liver stiffness was related to increased LV concentricity. This association was independent of diabetes and liver fat (Beta = 0.26, p = 0.0053), but was attenuated (Beta = 0.17, p = 0.077) when also adjusting for circulating levels of interleukin-1 receptor type 2. CONCLUSION: MRI reveals that liver fibrosis is associated to structural LV remodeling, in terms of increased concentricity, in participants from the general population. This relationship could involve the interleukin-1 signaling. CLINICAL RELEVANCE STATEMENT: Liver fibrosis may be considered a cardiovascular risk factor in patients without cirrhosis. Further research on the mechanisms that link liver fibrosis to left ventricular concentricity may reveal potential therapeutic targets in patients with non-alcoholic fatty liver disease (NAFLD). KEY POINTS: Previously, studies on liver fibrosis and cardiac remodeling have focused on advanced stages of liver fibrosis. Liver fibrosis is associated with left ventricular (LV) concentricity and may relate to interleukin-1 receptor type 2. Interleukin-1 signaling is a potential mechanistic interlink between early liver fibrosis and LV remodeling.

4.
J Physiol ; 601(17): 3765-3787, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37485733

RESUMO

Type 2 diabetes (T2D) and hypertension increase the risk of cardiovascular diseases mediated by whole-body changes to metabolism, cardiovascular structure and haemodynamics. The haemodynamic changes related to hypertension and T2D are complex and subject-specific, however, and not fully understood. We aimed to investigate the haemodynamic mechanisms in T2D and hypertension by comparing the haemodynamics between healthy controls and subjects with T2D, hypertension, or both. For all subjects, we combined 4D flow magnetic resonance imaging data, brachial blood pressure and a cardiovascular mathematical model to create a comprehensive subject-specific analysis of central haemodynamics. When comparing the subject-specific haemodynamic parameters between the four groups, the predominant haemodynamic difference is impaired left ventricular relaxation in subjects with both T2D and hypertension compared to subjects with only T2D, only hypertension and controls. The impaired relaxation indicates that, in this cohort, the long-term changes in haemodynamic load of co-existing T2D and hypertension cause diastolic dysfunction demonstrable at rest, whereas either disease on its own does not. However, through subject-specific predictions of impaired relaxation, we show that altered relaxation alone is not enough to explain the subject-specific and group-related differences; instead, a combination of parameters is affected in T2D and hypertension. These results confirm previous studies that reported more adverse effects from the combination of T2D and hypertension compared to either disease on its own. Furthermore, this shows the potential of personalized cardiovascular models in providing haemodynamic mechanistic insights and subject-specific predictions that could aid in the understanding and treatment planning of patients with T2D and hypertension. KEY POINTS: The combination of 4D flow magnetic resonance imaging data and a cardiovascular mathematical model allows for a comprehensive analysis of subject-specific haemodynamic parameters that otherwise cannot be derived non-invasively. Using this combination, we show that diastolic dysfunction in subjects with both type 2 diabetes (T2D) and hypertension is the main group-level difference between controls, subjects with T2D, subjects with hypertension, and subjects with both T2D and hypertension. These results suggest that, in this relatively healthy population, the additional load of both hypertension and T2D affects the haemodynamic function of the left ventricle, whereas each disease on its own is not enough to cause significant effects under resting conditions. Finally, using the subject-specific model, we show that the haemodynamic effects of diastolic dysfunction alone are not sufficient to explain all the observed haemodynamic differences. Instead, additional subject-specific variations in cardiac and vascular function combine to explain the complex haemodynamics of subjects affected by hypertension and/or T2D.


Assuntos
Diabetes Mellitus Tipo 2 , Hipertensão , Humanos , Modelos Cardiovasculares , Hemodinâmica , Imageamento por Ressonância Magnética , Ventrículos do Coração
5.
PLoS Comput Biol ; 18(9): e1010469, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36094958

RESUMO

Today, there is great interest in diets proposing new combinations of macronutrient compositions and fasting schedules. Unfortunately, there is little consensus regarding the impact of these different diets, since available studies measure different sets of variables in different populations, thus only providing partial, non-connected insights. We lack an approach for integrating all such partial insights into a useful and interconnected big picture. Herein, we present such an integrating tool. The tool uses a novel mathematical model that describes mechanisms regulating diet response and fasting metabolic fluxes, both for organ-organ crosstalk, and inside the liver. The tool can mechanistically explain and integrate data from several clinical studies, and correctly predict new independent data, including data from a new study. Using this model, we can predict non-measured variables, e.g. hepatic glycogen and gluconeogenesis, in response to fasting and different diets. Furthermore, we exemplify how such metabolic responses can be successfully adapted to a specific individual's sex, weight, height, as well as to the individual's historical data on metabolite dynamics. This tool enables an offline digital twin technology.


Assuntos
Jejum , Glicogênio Hepático , Dieta , Jejum/fisiologia , Gluconeogênese/fisiologia , Fígado/metabolismo , Glicogênio Hepático/metabolismo
6.
BMC Gastroenterol ; 23(1): 454, 2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-38129794

RESUMO

BACKGROUND: Liver cirrhosis, the advanced stage of many chronic liver diseases, is associated with escalated risks of liver-related complications like decompensation and hepatocellular carcinoma (HCC). Morbidity and mortality in cirrhosis patients are linked to portal hypertension, sarcopenia, and hepatocellular carcinoma. Although conventional cirrhosis management centered on treating complications, contemporary approaches prioritize preemptive measures. This study aims to formulate novel blood- and imaging-centric methodologies for monitoring liver cirrhosis patients. METHODS: In this prospective study, 150 liver cirrhosis patients will be enrolled from three Swedish liver clinics. Their conditions will be assessed through extensive blood-based markers and magnetic resonance imaging (MRI). The MRI protocol encompasses body composition profile with Muscle Assement Score, portal flow assessment, magnet resonance elastography, and a abbreviated MRI for HCC screening. Evaluation of lifestyle, muscular strength, physical performance, body composition, and quality of life will be conducted. Additionally, DNA, serum, and plasma biobanking will facilitate future investigations. DISCUSSION: The anticipated outcomes involve the identification and validation of non-invasive blood- and imaging-oriented biomarkers, enhancing the care paradigm for liver cirrhosis patients. Notably, the temporal evolution of these biomarkers will be crucial for understanding dynamic changes. TRIAL REGISTRATION: Clinicaltrials.gov, registration identifier NCT05502198. Registered on 16 August 2022. Link: https://classic. CLINICALTRIALS: gov/ct2/show/NCT05502198 .


Assuntos
Carcinoma Hepatocelular , Doença Hepática Terminal , Hipertensão Portal , Neoplasias Hepáticas , Sarcopenia , Humanos , Bancos de Espécimes Biológicos , Biomarcadores , Caquexia/etiologia , Caquexia/complicações , Carcinoma Hepatocelular/epidemiologia , Hipertensão Portal/complicações , Hipertensão Portal/patologia , Cirrose Hepática/diagnóstico , Neoplasias Hepáticas/epidemiologia , Estudos Prospectivos , Qualidade de Vida , Sarcopenia/diagnóstico por imagem , Sarcopenia/etiologia
7.
Br J Cancer ; 127(11): 2025-2033, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36138072

RESUMO

BACKGROUND: High mammographic density is an independent risk factor for breast cancer by poorly understood molecular mechanisms. Women with dense breasts often undergo conventional magnetic resonance imaging (MRI) despite its limited specificity, which may be increased by diffusion-weighted imaging (DWI) with apparent diffusion coefficient (ADC) and contrast. How these modalities are affected by breast density per se and their association with the local microenvironment are undetermined. METHODS: Healthy postmenopausal women attending mammography screen with extremely dense or entirely fatty breasts underwent multiparametric MRI for analyses of lean tissue fraction (LTF), ADC and perfusion dynamics. Microdialysis was used for extracellular proteomics in situ. RESULTS: Significantly increased LTF and ADC and delayed perfusion were detected in dense breasts. In total, 270 proteins were quantified, whereof 124 related to inflammation, angiogenesis, and cellular growth were significantly upregulated in dense breasts. Most of these correlated significantly with LTF, ADC and the perfusion data. CONCLUSIONS: ADC and perfusion characteristics depend on breast density, which should be considered during the implementation of thresholds for malignant lesions. Dense and nondense breasts are two essentially different biological entities, with a pro-tumorigenic microenvironment in dense breasts. Our data reveal several novel pathways that may be explored for breast cancer prevention strategies.


Assuntos
Neoplasias da Mama , Imageamento por Ressonância Magnética Multiparamétrica , Feminino , Humanos , Densidade da Mama , Mamografia/métodos , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Carcinogênese , Biomarcadores , Microambiente Tumoral
8.
Eur Radiol ; 32(1): 477-488, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34286376

RESUMO

OBJECTIVES: The purpose of this study was to develop a procedure to investigate the occurrence, character and causes of magnetic resonance (MR) imaging incidents. METHODS: A semi-structured questionnaire was developed containing details such as safety zones, examination complexity, staff MR knowledge, staff categories, and implementation of EU directive 2013/35. We focused on formally reported incidents that had occurred during 2014-2019, and unreported incidents during one year. Thirteen clinical MR units were visited, and the managing radiographer was interviewed. Open questions were analysed using conventionally adopted content analysis. RESULTS: Thirty-seven written reports for 5 years and an additional 12 oral reports for 1 year were analysed. Only 38% of the incidents were reported formally. Some of these incidents were catastrophic. Negative correlations were observed between the number of annual incidents (per scanner) and staff MR knowledge (Spearman's rho - 0.41, p < 0.05) as well as the number of MR physicists per scanner (- 0.48, p < 0.05). It was notable that only half of the sites had implemented the EU directive. Quotes like 'Burns are to be expected in MR' and not even knowing the name of the incident reporting system suggested an inadequate safety culture. Finally, there was a desire among staff for MR safety education. CONCLUSIONS: MR-related incidents were greatly underreported, and some incidents could have had catastrophic outcomes. There is a great desire among radiographers to enhance the safety culture, but to achieve this, much more accessible education is required, as well as focused involvement of the management of the operations. KEY POINTS: • Only one in three magnetic resonance-related incidents were reported. • Several magnetic resonance incidents could have led to catastrophic consequences. • Much increased knowledge about magnetic resonance safety is needed by radiologists and radiographers.


Assuntos
Erros Médicos , Gestão de Riscos , Humanos , Imageamento por Ressonância Magnética , Gestão da Segurança , Inquéritos e Questionários
9.
BMC Gastroenterol ; 21(1): 180, 2021 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-33879084

RESUMO

BACKGROUND: Non-alcoholic fatty liver disease (NAFLD) affects 20-30% of the general adult population. NAFLD patients with type 2 diabetes mellitus (T2DM) are at an increased risk of advanced fibrosis, which puts them at risk of cardiovascular complications, hepatocellular carcinoma, or liver failure. Liver biopsy is the gold standard for assessing hepatic fibrosis. However, its utility is inherently limited. Consequently, the prevalence and characteristics of T2DM patients with advanced fibrosis are unknown. Therefore, the purpose of the current study is to evaluate the prevalence and severity of NAFLD in patients with T2DM by recruiting participants from primary care, using the latest imaging modalities, to collect a cohort of well phenotyped patients. METHODS: We will prospectively recruit 400 patients with T2DM using biomarkers to assess their status. Specifically, we will evaluate liver fat content using magnetic resonance imaging (MRI); hepatic fibrosis using MR elastography and vibration-controlled transient elastography; muscle composition and body fat distribution using water-fat separated whole body MRI; and cardiac function, structure, and tissue characteristics, using cardiovascular MRI. DISCUSSION: We expect that the study will uncover potential mechanisms of advanced hepatic fibrosis in NAFLD and T2DM and equip the clinician with better diagnostic tools for the care of T2DM patients with NAFLD. TRIAL REGISTRATION: Clinicaltrials.gov, identifier NCT03864510. Registered 6 March 2019, https://clinicaltrials.gov/ct2/show/NCT03864510 .


Assuntos
Diabetes Mellitus Tipo 2 , Hepatopatia Gordurosa não Alcoólica , Adulto , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/epidemiologia , Humanos , Cirrose Hepática , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/diagnóstico por imagem , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Prevalência , Atenção Primária à Saúde , Fatores de Risco
10.
PLoS Comput Biol ; 15(6): e1007157, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31237870

RESUMO

Estimation of liver function is important to monitor progression of chronic liver disease (CLD). A promising method is magnetic resonance imaging (MRI) combined with gadoxetate, a liver-specific contrast agent. For this method, we have previously developed a model for an average healthy human. Herein, we extended this model, by combining it with a patient-specific non-linear mixed-effects modeling framework. We validated the model by recruiting 100 patients with CLD of varying severity and etiologies. The model explained all MRI data and adequately predicted both timepoints saved for validation and gadoxetate concentrations in both plasma and biopsies. The validated model provides a new and deeper look into how the mechanisms of liver function vary across a wide variety of liver diseases. The basic mechanisms remain the same, but increasing fibrosis reduces uptake and increases excretion of gadoxetate. These mechanisms are shared across many liver functions and can now be estimated from standard clinical images.


Assuntos
Interpretação de Imagem Assistida por Computador/métodos , Fígado/diagnóstico por imagem , Fígado/metabolismo , Imageamento por Ressonância Magnética/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Gadolínio DTPA/farmacocinética , Humanos , Cirrose Hepática/diagnóstico por imagem , Cirrose Hepática/metabolismo , Testes de Função Hepática , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Reprodutibilidade dos Testes , Adulto Jovem
11.
Scand J Gastroenterol ; 55(7): 848-859, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32684060

RESUMO

BACKGROUND AND AIMS: Accurate biomarkers for quantifying liver fibrosis are important for clinical practice and trial end-points. We compared the diagnostic performance of magnetic resonance imaging (MRI), including gadoxetate-enhanced MRI and 31P-MR spectroscopy, with fibrosis stage and serum fibrosis algorithms in a clinical setting. Also, in a subset of patients, MR- and transient elastography (MRE and TE) was evaluated when available. METHODS: Patients were recruited prospectively if they were scheduled to undergo liver biopsy on a clinical indication due to elevated liver enzyme levels without decompensated cirrhosis. Within a month of the clinical work-up, an MR-examination and liver needle biopsy were performed on the same day. Based on late-phase gadoxetate-enhanced MRI, a mathematical model calculated hepatobiliary function (relating to OATP1 and MRP2). The hepatocyte gadoxetate uptake rate (KHep) and the normalised liver-to-spleen contrast ratio (LSC_N10) were also calculated. Nine serum fibrosis algorithms were investigated (GUCI, King's Score, APRI, FIB-4, Lok-Index, NIKEI, NASH-CRN regression score, Forns' score, and NAFLD-fibrosis score). RESULTS: The diagnostic performance (AUROC) for identification of significant fibrosis (F2-4) was 0.78, 0.80, 0.69, and 0.78 for MRE, TE, LSC_N10, and GUCI, respectively. For the identification of advanced fibrosis (F3-4), the AUROCs were 0.93, 0.84, 0.81, and 0.82 respectively. CONCLUSION: MRE and TE were superior for non-invasive identification of significant fibrosis. Serum fibrosis algorithms developed for specific liver diseases are applicable in this cohort of diverse liver diseases aetiologies. Gadoxetate-MRI was sufficiently sensitive to detect the low function losses associated with fibrosis. None was able to efficiently distinguish between stages within the low fibrosis stages.Lay summaryExcessive accumulation of scar tissue, fibrosis, in the liver is an important aspect in chronic liver disease. To replace the invasive needle biopsy, we have explored non-invasive methods to assess liver fibrosis. In our study we found that elastographic methods, which assess the mechanical properties of the liver, are superior in assessing fibrosis in a clinical setting. Of interest from a clinical trial point-of-view, none of the tested methods was sufficiently accurate to distinguish between adjacent moderate fibrosis stages.


Assuntos
Biomarcadores/sangue , Técnicas de Imagem por Elasticidade , Cirrose Hepática/sangue , Cirrose Hepática/diagnóstico por imagem , Imageamento por Ressonância Magnética , Adulto , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Área Sob a Curva , Feminino , Humanos , Fígado/patologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Curva ROC , Suécia , Adulto Jovem
12.
Acta Neurol Scand ; 142(5): 418-427, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32416627

RESUMO

BACKGROUND: Optical coherence tomography (OCT) could be complementary to magnetic resonance imaging (MRI) of the brain in monitoring course of multiple sclerosis (MS) and clinically isolated syndrome (CIS). Thinning of neurons in ganglion cell-inner plexiform layer (GCIPL) measured by OCT is assumed to be associated with brain atrophy. OBJECTIVES: To evaluate association of GCIPL with brain parameters detected by quantitative MRI (qMRI) and MR-spectroscopy (MRS) in early MS and CIS. METHODS: Seventeen newly diagnosed MS and 18 CIS patients were prospectively included. The patients were assessed at baseline as well as at 1 year follow-up by OCT, qMRI and MRS. Brain parenchymal and myelin volumes (BPV, MYV respectively) and the corresponding fractions (BPF, MYF) were measured with qMRI. Metabolites including myo-inositol (myo-Ins) were measured in the normal-appearing white matter (NAWM) using MRS. T-tests and ANOVA were used to analyze group differences, and linear regression models to evaluate association of GCIPL with BPV, MYV and myo-Ins after correlation analysis. RESULTS: Disease activity reflected by lesions on MRI and presence of CSF oligoclonal IgG bands were more prominent in MS compared to CIS. GCIPL, BPV, MYV, BPF and MYF were reduced, while concentration of myo-Ins was increased in MS compared to CIS. Follow-up showed consistency of thinner GCIPL in MS compared to CIS. GCIPL thinning correlated with reduced BPV and MYV (P < .05 for both), but with increased myo-Ins (P < .01). CONCLUSIONS: Significant GCIPL thinning occurs in early MS and is associated with enhanced brain inflammation and atrophy.


Assuntos
Doenças Desmielinizantes/patologia , Esclerose Múltipla/patologia , Retina/patologia , Tomografia de Coerência Óptica/métodos , Adolescente , Adulto , Atrofia/patologia , Doenças Desmielinizantes/diagnóstico por imagem , Progressão da Doença , Diagnóstico Precoce , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/diagnóstico , Neuroimagem/métodos , Adulto Jovem
13.
Magn Reson Med ; 81(4): 2223-2237, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30417930

RESUMO

PURPOSE: To develop a method for retrospective artifact elimination of MRS data. This retrospective method was based on an approach that combines jackknife analyses with the correlation of spectral windows, and therefore termed "JKC." METHODS: Twelve healthy volunteers performed 3 separate measurement protocols using a 3T MR system. One protocol consisted of 2 cerebellar MEGA-PRESS measurements: 1 reference and 1 measurement including head movements. One-third of the artifact-influenced datasets were treated as training data for the implementation the JKC method, and the rest were used for validation. RESULTS: The implemented JKC method correctly characterized most of the validation data. Additionally, after elimination of the detected artifacts, the resulting concentrations were much closer to those computed for the reference datasets. Moreover, when the JKC method was applied to the reference data, the estimated concentrations were not affected, compared with standard averaging. CONCLUSION: The implemented JKC method can be applied without any extra cost to MRS data, regardless of whether the dataset has been contaminated by artifacts. Furthermore, the results indicate that the JKC method could be used as a quality control of a dataset, or as an indication of whether a shift in voxel placement has occurred during the measurement.


Assuntos
Artefatos , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Adulto , Algoritmos , Feminino , Cabeça/diagnóstico por imagem , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Movimento , Imagens de Fantasmas , Valores de Referência , Adulto Jovem , Ácido gama-Aminobutírico
14.
J Magn Reson Imaging ; 50(1): 325-333, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30637926

RESUMO

BACKGROUND: Liver iron content (LIC) in chronic liver disease (CLD) is currently determined by performing an invasive liver biopsy. MRI using R2* relaxometry is a noninvasive alternative for estimating LIC. Fat accumulation in the liver, or proton density fat fraction (PDFF), may be a possible confounder of R2* measurements. Previous studies of the effect of PDFF on R2* have not used quantitative LIC measurement. PURPOSE: To assess the associations between R2*, LIC, PDFF, and liver histology in patients with suspected CLD. STUDY TYPE: Prospective. POPULATION: Eighty-one patients with suspected CLD. FIELD STRENGTH/SEQUENCE: 1.5 T. Multiecho turbo field echo to quantify R2*. PRESS MRS to quantify PDFF. ASSESSMENT: Each patient underwent an MR examination, followed by two needle biopsies immediately following the MR examination. The first biopsy was used for conventional histological assessment of LIC, whereas the second biopsy was used to quantitatively measure LIC using mass spectrometry. R2* was correlated with both LIC and PDFF. A correction for the influence of fat on R2* was calculated. STATISTICAL TESTS: Pearson correlation, linear regression, and area under the receiver operating curve. RESULTS: There was a positive linear correlation between R2* and PDFF (R = 0.69), after removing data from patients with elevated iron levels, as defined by LIC. R2*, corrected for PDFF, was the best method for identifying patients with elevated iron levels, with a correlation of R = 0.87 and a sensitivity and specificity of 87.5% and 98.6%, respectively. DATA CONCLUSION: PDFF increases R2*. LEVEL OF EVIDENCE: 2 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2019;50:325-333.


Assuntos
Sobrecarga de Ferro/diagnóstico por imagem , Hepatopatias/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Biópsia por Agulha , Doença Crônica , Feminino , Humanos , Masculino , Espectrometria de Massas , Pessoa de Meia-Idade , Estudos Prospectivos , Sensibilidade e Especificidade
15.
Gastroenterology ; 153(1): 53-55.e7, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28286210

RESUMO

It is possible to estimate hepatic triglyceride content by calculating the proton density fat fraction (PDFF), using proton magnetic resonance spectroscopy (1H-MRS), instead of collecting and analyzing liver biopsy specimens to detect steatosis. However, the current PDFF cut-off value (5%) used to define steatosis by magnetic resonance was derived from studies that did not use histopathology as the reference standard. We performed a prospective study to determine the accuracy of 1H-MRS PDFF in the measurement of steatosis using histopathology analysis as the standard. We collected clinical, serologic, 1H-MRS PDFF, and liver biopsy data from 94 adult patients with increased levels of liver enzymes (≥6 mo) referred to the Department of Gastroenterology and Hepatology at Linköping University Hospital in Sweden from 2007 through 2014. Steatosis was graded using the conventional histopathology method and fat content was quantified in biopsy samples using stereologic point counts (SPCs). We correlated the 1H-MRS PDFF findings with SPCs (r = 0.92; P < .001). 1H-MRS PDFF results correlated with histopathology results (ρ = 0.87; P < .001), and SPCs correlated with histopathology results (ρ = 0.88; P < .001). All 25 subjects with PDFF values of 5.0% or more had steatosis based on histopathology findings (100% specificity for PDFF). However, of 69 subjects with PDFF values less than 5.0% (negative result), 22 were determined to have steatosis based on histopathology findings (53% sensitivity for PDFF). Reducing the PDFF cut-off value to 3.0% identified patients with steatosis with 100% specificity and 79% sensitivity; a PDFF cut-off value of 2.0% identified patients with steatosis with 94% specificity and 87% sensitivity. These findings might be used to improve noninvasive detection of steatosis.


Assuntos
Fígado/patologia , Espectroscopia de Ressonância Magnética , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Hepatopatia Gordurosa não Alcoólica/patologia , Triglicerídeos/análise , Adiposidade , Adulto , Idoso , Biópsia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Valores de Referência , Sensibilidade e Especificidade
16.
J Neuroinflammation ; 15(1): 209, 2018 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-30021640

RESUMO

BACKGROUND: There is a need for clinically useful biomarkers of disease activity in clinically isolated syndrome (CIS) and relapsing remitting MS (RRMS). The aim of this study was to assess the correlation between neurofilament light chain (NFL) in cerebrospinal fluid (CSF) and serum and the relationship between NFL and other biomarkers, subsequent disease activity, and brain volume loss in CIS and RRMS. METHODS: A panel of neurodegenerative and neuroinflammatory markers were analyzed in repeated CSF samples from 41 patients with CIS or RRMS in a prospective longitudinal cohort study and from 22 healthy controls. NFL in serum was analyzed using a single-molecule array (Simoa) method. "No evidence of disease activity-3" (NEDA-3) status and brain volume (brain parenchymal fraction calculated using SyMRI®) were recorded during 4 years of follow-up. RESULTS: NFL levels in CSF and serum correlated significantly (all samples, n = 63, r 0.74, p < 0.001), but CSF-NFL showed an overall stronger association profile with NEDA-3 status, new T2 lesions, and brain volume loss. CSF-NFL was associated with both new T2 lesions and brain volume loss during follow-up, whereas CSF-CHI3L1 was associated mainly with brain volume loss and CXCL1, CXCL10, CXCL13, CCL22, and MMP-9 were associated mainly with new T2 lesions. CONCLUSIONS: Serum and CSF levels of NFL correlate, but CSF-NFL predicts and reflects disease activity better than S-NFL. CSF-NFL levels are associated with both new T2 lesions and brain volume loss. Our findings further add to the accumulating evidence that CSF-NFL is a clinically useful biomarker in CIS and RRMS and should be considered in the expanding NEDA concept. CSF-CXCL10 and CSF-CSF-CHI3L1 are potential markers of disease activity and brain volume loss, respectively.


Assuntos
Encéfalo/diagnóstico por imagem , Esclerose Múltipla , Proteínas de Neurofilamentos/sangue , Proteínas de Neurofilamentos/líquido cefalorraquidiano , Adulto , Quimiocinas/sangue , Quimiocinas/líquido cefalorraquidiano , Avaliação da Deficiência , Feminino , Seguimentos , Humanos , Processamento de Imagem Assistida por Computador , Modelos Lineares , Imageamento por Ressonância Magnética , Masculino , Esclerose Múltipla/sangue , Esclerose Múltipla/líquido cefalorraquidiano , Esclerose Múltipla/diagnóstico por imagem , Curva ROC , Estudos Retrospectivos , Adulto Jovem
17.
Ann Surg Oncol ; 23(Suppl 5): 737-745, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27600619

RESUMO

OBJECTIVE: This study was designed to identify factors associated with morbidity and mortality in patients older than 70 years who underwent cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) for peritoneal carcinomatosis (PC). BACKGROUND: Major surgery is associated with higher morbidity and mortality in elderly patients. For PC, CRS and HIPEC is the only current potential curative therapy, but the risks inherent to this patient population have called its benefits into question. METHODS: We retrospectively analyzed a multi-center database from 1989 to 2015. All patients who underwent CRS and HIPEC for PC were selected and patients older than 70 years were matched 1:4 with a younger cohort according to cancer origin, peritoneal cancer index (PCI), and completeness of cytoreduction. Major morbidity and mortality were analyzed. RESULTS: Of 2328 patients, 188 patients older than aged 70 years were matched with 704 younger patients. Patients older than aged 70 years demonstrated a higher American Society of Anesthesiologist score (≥ASA III 10.8 vs. 6.6 %, p = 0.008). There was no difference in overall 90-day morbidity (≥70: 45.7 % vs. <70: 44.5 %; p = 0.171); however, patients older than 70 years had significantly more cardiovascular complications (13.8 vs. 9.2 %, p = 0.044). Differences between the older and younger cohorts failed to reach significance for 90-day mortality (5.4 and 2.7 %, respectively; p = 0.052), and failure-to-rescue (11.6 and 6.1 %, respectively; p = 0.078). In multivariate analysis, PCI > 7 (95 % CI 1.051-5.798, p = 0.038) and HIPEC duration (95 % CI 1.106-6.235, p = 0.028) were independent factors associated with morbidity in elderly patients. CONCLUSIONS: CRS and HIPEC appear feasible for selected patients older than aged 70 years, albeit with a higher risk of medical complications associated with increased mortality.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Procedimentos Cirúrgicos de Citorredução/efeitos adversos , Hipertermia Induzida/efeitos adversos , Neoplasias Peritoneais/terapia , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Doenças Cardiovasculares/etiologia , Estudos de Casos e Controles , Causas de Morte , Terapia Combinada/efeitos adversos , Falha da Terapia de Resgate , Feminino , Nível de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Peritoneais/secundário , Estudos Retrospectivos , Adulto Jovem
18.
J Magn Reson Imaging ; 42(2): 468-76, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25355066

RESUMO

PURPOSE: To quantitatively and qualitatively evaluate the water-signal performance of the consistent intensity inhomogeneity correction (CIIC) method to correct for intensity inhomogeneities METHODS: Water-fat volumes were acquired using 1.5 Tesla (T) and 3.0T symmetrically sampled 2-point Dixon three-dimensional MRI. Two datasets: (i) 10 muscle tissue regions of interest (ROIs) from 10 subjects acquired with both 1.5T and 3.0T whole-body MRI. (ii) Seven liver tissue ROIs from 36 patients imaged using 1.5T MRI at six time points after Gd-EOB-DTPA injection. The performance of CIIC was evaluated quantitatively by analyzing its impact on the dispersion and bias of the water image ROI intensities, and qualitatively using side-by-side image comparisons. RESULTS: CIIC significantly ( P1.5T≤2.3×10-4,P3.0T≤1.0×10-6) decreased the nonphysiological intensity variance while preserving the average intensity levels. The side-by-side comparisons showed improved intensity consistency ( Pint⁡≤10-6) while not introducing artifacts ( Part=0.024) nor changed appearances ( Papp≤10-6). CONCLUSION: CIIC improves the spatiotemporal intensity consistency in regions of a homogenous tissue type.


Assuntos
Tecido Adiposo/anatomia & histologia , Artefatos , Água Corporal/metabolismo , Imageamento por Ressonância Magnética/métodos , Músculo Esquelético/anatomia & histologia , Músculo Esquelético/metabolismo , Adulto , Humanos , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Masculino , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Processamento de Sinais Assistido por Computador , Técnica de Subtração
19.
NPJ Digit Med ; 7(1): 112, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38702474

RESUMO

Alcohol consumption is associated with a wide variety of preventable health complications and is a major risk factor for all-cause mortality in the age group 15-47 years. To reduce dangerous drinking behavior, eHealth applications have shown promise. A particularly interesting potential lies in the combination of eHealth apps with mathematical models. However, existing mathematical models do not consider real-life situations, such as combined intake of meals and beverages, and do not connect drinking to clinical markers, such as phosphatidylethanol (PEth). Herein, we present such a model which can simulate real-life situations and connect drinking to long-term markers. The new model can accurately describe both estimation data according to a χ2 -test (187.0 < Tχ2 = 226.4) and independent validation data (70.8 < Tχ2 = 93.5). The model can also be personalized using anthropometric data from a specific individual and can thus be used as a physiologically-based digital twin. This twin is also able to connect short-term consumption of alcohol to the long-term dynamics of PEth levels in the blood, a clinical biomarker of alcohol consumption. Here we illustrate how connecting short-term consumption to long-term markers allows for a new way to determine patient alcohol consumption from measured PEth levels. An additional use case of the twin could include the combined evaluation of patient-reported AUDIT forms and measured PEth levels. Finally, we integrated the new model into an eHealth application, which could help guide individual users or clinicians to help reduce dangerous drinking.

20.
Clin Nutr ; 43(6): 1532-1543, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38754305

RESUMO

BACKGROUND & AIMS: Non-alcoholic fatty liver disease (NAFLD) is a common metabolic disorder, characterized by the accumulation of excess fat in the liver, and is a driving factor for various severe liver diseases. These multi-factorial and multi-timescale changes are observed in different clinical studies, but these studies have not been integrated into a unified framework. In this study, we aim to present such a unified framework in the form of a dynamic mathematical model. METHODS: For model training and validation, we collected data for dietary or drug-induced interventions aimed at reducing or increasing liver fat. The model was formulated using ordinary differential equations (ODEs) and the mathematical analysis, model simulation, model formulation and the model parameter estimation were all performed in MATLAB. RESULTS: Our mathematical model describes accumulation of fat in the liver and predicts changes in lipid fluxes induced by both dietary and drug interventions. The model is validated using data from a wide range of drug and dietary intervention studies and can predict both short-term (days) and long-term (weeks) changes in liver fat. Importantly, the model computes the contribution of each individual lipid flux to the total liver fat dynamics. Furthermore, the model can be combined with an established bodyweight model, to simulate even longer scenarios (years), also including the effects of insulin resistance and body weight. To help prepare for corresponding eHealth applications, we also present a way to visualize the simulated changes, using dynamically changing lipid droplets, seen in images of liver biopsies. CONCLUSION: In conclusion, we believe that the minimal model presented herein might be a useful tool for future applications, and to further integrate and understand data regarding changes in dietary and drug induced changes in ectopic TAG in the liver. With further development and validation, the minimal model could be used as a disease progression model for steatosis.


Assuntos
Fígado , Hepatopatia Gordurosa não Alcoólica , Humanos , Hepatopatia Gordurosa não Alcoólica/dietoterapia , Fígado/metabolismo , Modelos Teóricos , Dieta/métodos , Modelos Biológicos , Metabolismo dos Lipídeos
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