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1.
Eur Radiol ; 32(11): 7409-7419, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35482122

RESUMO

OBJECTIVES: Abbreviated breast MRI (AB-MRI) was introduced to reduce both examination and image reading times and to improve cost-effectiveness of breast cancer screening. The aim of this model-based economic study was to analyze the cost-effectiveness of full protocol breast MRI (FB-MRI) vs. AB-MRI in screening women with dense breast tissue for breast cancer. METHODS: Decision analysis and a Markov model were designed to model the cumulative costs and effects of biennial screening in terms of quality-adjusted life years (QALYs) from a US healthcare system perspective. Model input parameters for a cohort of women with dense breast tissue were adopted from recent literature. The impact of varying AB-MRI costs per examination as well as specificity on the resulting cost-effectiveness was modeled within deterministic sensitivity analyses. RESULTS: At an assumed cost per examination of $ 263 for AB-MRI (84% of the cost of a FB-MRI examination), the discounted cumulative costs of both MR-based strategies accounted comparably. Reducing the costs of AB-MRI below $ 259 (82% of the cost of a FB-MRI examination, respectively), the incremental cost-effectiveness ratio of FB-MRI exceeded the willingness to pay threshold and the AB-MRI-strategy should be considered preferable in terms of cost-effectiveness. CONCLUSIONS: Our preliminary findings indicate that AB-MRI may be considered cost-effective compared to FB-MRI for screening women with dense breast tissue for breast cancer, as long as the costs per examination do not exceed 82% of the cost of a FB-MRI examination. KEY POINTS: • Cost-effectiveness of abbreviated breast MRI is affected by reductions in specificity and resulting false positive findings and increased recall rates. • Abbreviated breast MRI may be cost-effective up to a cost per examination of 82% of the cost of a full protocol examination. • Abbreviated breast MRI could be an economically preferable alternative to full protocol breast MRI in screening women with dense breast tissue.


Assuntos
Neoplasias da Mama , Feminino , Humanos , Neoplasias da Mama/diagnóstico , Mamografia/métodos , Densidade da Mama , Detecção Precoce de Câncer/métodos , Programas de Rastreamento , Imageamento por Ressonância Magnética/métodos , Análise Custo-Benefício , Anos de Vida Ajustados por Qualidade de Vida
2.
Rofo ; 194(1): 29-38, 2022 01.
Artigo em Inglês, Alemão | MEDLINE | ID: mdl-34139781

RESUMO

BACKGROUND: Diagnostic radiological examinations as well as interventional radiological therapies are performed at a steadily increasing rate amidst increasingly limited resources in healthcare systems. Given their potential to contribute decisively to optimized therapy, in most cases associated short-term direct costs can be well justified from a clinical perspective. However, to realize their clinical benefits, they must also succeed in justifying them to payers and policymakers. Therefore, the aim of this work is to present suitable methods for economic analysis of radiological precedures and to elaborate their relevance for radiology. METHODOLOGY: Methods and metrics of cost-effectiveness analysis are presented and then exemplified using the example cases of MR mammography and interventional treatment of oligometastatic tumor disease of the liver. RESULTS: Cost-effectiveness considerations, taking into account long-term gains in lifespan and quality of life, as well as potential savings through improved treatment planning, do often objectively and credibly justify short-term additional costs. CONCLUSIONS: Cost-effectiveness analyses performed with radiological and health economic expertise can support the establishment of new radiological technologies in diagnostics and therapy. KEY POINTS: · When radiological procedures are employed, short-term costs are often offset by significant long-term benefits.. · Radiological examinations and therapies must be justified in the context of limited economic resources.. · Economic methodologies can be used to quantify the quality and cost-effectiveness of radiological methods.. · Such analyses as well as targeted training should be encouraged to provide greater transparency.. CITATION FORMAT: · Froelich MF, Kunz WG, Tollens F et al. Cost-effectiveness analysis in radiology: methods, results and implications. Fortschr Röntgenstr 2022; 194: 29 - 38.


Assuntos
Qualidade de Vida , Radiologia Intervencionista , Análise Custo-Benefício , Mamografia , Radiografia
3.
Transl Oncol ; 11(2): 243-249, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29413756

RESUMO

OBJECTIVE: To investigate promoting factors for background parenchymal enhancement (BPE) in MR mammography (MRM). METHODS: 146 patients were retrospectively evaluated, including 91 high-risk patients (50 BRCA patients, 41 patients with elevated lifetime risk). 56 screening patients were matched to the high-risk cases on the basis of age. The correlation of BPE with factors such as fibroglandular tissue (FGT), age, menopausal status, breast cancer, high-risk precondition as well as motion were investigated using linear regression. RESULTS: BPE positively correlated with FGT (P<.001) and negatively correlated with menopausal status (P<.001). Cancer did not show an effect on BPE (P>.05). A high-risk precondition showed a significant impact on the formation of BPE (P<.05). However, when corrected for motion, the correlation between BPE and a high-risk precondition became weak and insignificant, and a highly significant association between BPE and motion was revealed (P<.01). CONCLUSION: BPE positively correlated with FGT and negatively correlated with age. Cancer did not have an effect on BPE. A high-risk precondition appears to have a negative effect on BPE. However, when corrected for motion, high-risk preconditions became insignificant. Technical as well as physiological influences seem to play an important role in the formation of BPE.

4.
Rofo ; 189(11): 1047-1054, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28863413

RESUMO

Background MRI is attractive for guiding and monitoring interventional procedures due to its high intrinsic soft tissue contrast and the possibility to measure flow and cardiac function. Methods Technical solutions have been developed for all procedural steps including imaging guidance, MR-safe catheters and instruments and patient monitoring. This has led to widening of the clinical applications. Interventional MRI is becoming increasingly important for the treatment of patients suffering from malignant diseases. The detectability of masses and consequently their accessibility for biopsy is higher, compared to other modalities, due to the high intrinsic soft tissue contrast of MRI. Temperature-dependent sequences allow for minimally invasive and tissue-sparing ablation (A-0 ablation). Conclusion Interventional MRI has become established in the clinical routine for a variety of indications, including biopsies and tumor ablation. Since the economic requirement of covering costs by reimbursement is met and interventional MRI decreases the mortality and morbidity of interventional procedures, broader application of interventional MRI can be expected in the clinical routine in the future. Key points · Particularly for the treatment of oncological patients, interventional MRI is superior to other methods with respect to minimal invasiveness and tissue protection due to the ability to exactly determine tumor borders and to visualize and control the size of the ablation area on the basis of MR temperature measurement.. · Due to the better visualization of targets and the effects of ablation in tissue, interventional MRI can lower the mortality and morbidity associated with these interventions for many indications.. · The complex comparison of costs and reimbursement shows that this application can be performed in a cost-covering manner and broader application can be expected in the future.. Citation Format · Barkhausen J, Kahn T, Krombach GA et al. White Paper: Interventional MRI: Current Status and Potential for Development Considering Economic Perspectives, Part 2: Liver and Other Applications in Oncology. Fortschr Röntgenstr 2017; 189: 1047 - 1054.


Assuntos
Previsões , Aumento da Imagem/métodos , Imagem por Ressonância Magnética Intervencionista/economia , Imagem por Ressonância Magnética Intervencionista/tendências , Neoplasias/diagnóstico por imagem , Neoplasias/terapia , Alemanha , Neoplasias/economia , Cirurgia Assistida por Computador/economia , Cirurgia Assistida por Computador/tendências
5.
Rofo ; 189(7): 611-623, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28651276

RESUMO

Background MRI is attractive for the guiding and monitoring of interventional procedures due to its high intrinsic soft tissue contrast and the possibility to measure physiologic parameters like flow and cardiac function. Method The current status of interventional MRI for the clinical routine was analyzed. Results The effort needed for the development of MR-safe monitoring systems and instruments initially resulted in the application of interventional MRI only for procedures that could not be performed by other means. Accordingly, biopsy of lesions in the breast, which are not detectable by other modalities, has been performed under MRI guidance for decades. Currently, biopsies of the prostate under MRI guidance are established in a similar fashion. At many sites blind biopsy has already been replaced by MR-guided biopsy or at least by the fusion of MR images with ultrasound. Cardiovascular interventions are performed at several centers for ablation as a treatment for atrial fibrillation. Conclusion Interventional MRI has been established in the clinical routine for a variety of indications. Broader application can be expected in the clinical routine in the future owing to the multiple advantages compared to other techniques. Key points · Due to the significant technical effort, MR-guided interventions are only recommended in the long term for regions in which MRI either facilitates or greatly improves the intervention.. · Breast biopsy of otherwise undetectable target lesions has long been established in the clinical routine. Prostate biopsy is currently being introduced in the clinical routine for similar reasons. Other methods such as MR-guided focused ultrasound for the treatment of uterine fibroids or tumor ablation of metastases represent alternative methods and are offered in many places.. · Endovascular MR-guided interventions offer advantages for a number of indications and have already been clinically established for the treatment of children with congenital heart defects and for atrial ablation at individual centers. Greater application can be expected in the future.. Citation format · Barkhausen J, Kahn T, Krombach GA et al. White Paper: Interventional MRI: Current Status and Potential for Development Considering Economic Perspectives, Part 1: General Application. Fortschr Röntgenstr 2017; 189: 611 - 623.


Assuntos
Imagem por Ressonância Magnética Intervencionista/economia , Imagem por Ressonância Magnética Intervencionista/tendências , Programas Nacionais de Saúde/economia , Programas Nacionais de Saúde/tendências , Cirurgia Assistida por Computador/economia , Cirurgia Assistida por Computador/tendências , Técnicas de Ablação/economia , Técnicas de Ablação/instrumentação , Técnicas de Ablação/tendências , Biópsia/economia , Biópsia/instrumentação , Biópsia/tendências , Análise Custo-Benefício , Procedimentos Endovasculares/economia , Procedimentos Endovasculares/instrumentação , Procedimentos Endovasculares/tendências , Alemanha , Humanos , Imagem por Ressonância Magnética Intervencionista/instrumentação , Neuronavegação/economia , Neuronavegação/instrumentação , Neuronavegação/tendências , Cirurgia Assistida por Computador/instrumentação , Pesquisa Translacional Biomédica/economia , Pesquisa Translacional Biomédica/tendências
6.
PLoS One ; 9(11): e110401, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25369020

RESUMO

Yttrium-90 is known to have a low positron emission decay of 32 ppm that may allow for personalized dosimetry of liver cancer therapy with (90)Y labeled microspheres. The aim of this work was to image and quantify (90)Y so that accurate predictions of the absorbed dose can be made. The measurements were performed within the QUEST study (University of Sydney, and Sirtex Medical, Australia). A NEMA IEC body phantom containing 6 fillable spheres (10-37 mm ∅) was used to measure the 90Y distribution with a Biograph mCT PET/CT (Siemens, Erlangen, Germany) with time-of-flight (TOF) acquisition. A sphere to background ratio of 8:1, with a total (90)Y activity of 3 GBq was used. Measurements were performed for one week (0, 3, 5 and 7 d). he acquisition protocol consisted of 30 min-2 bed positions and 120 min-single bed position. Images were reconstructed with 3D ordered subset expectation maximization (OSEM) and point spread function (PSF) for iteration numbers of 1-12 with 21 (TOF) and 24 (non-TOF) subsets and CT based attenuation and scatter correction. Convergence of algorithms and activity recovery was assessed based on regions-of-interest (ROI) analysis of the background (100 voxels), spheres (4 voxels) and the central low density insert (25 voxels). For the largest sphere, the recovery coefficient (RC) values for the 30 min -2-bed position, 30 min-single bed and 120 min-single bed were 1.12 ± 0.20, 1.14 ± 0.13, 0.97 ± 0.07 respectively. For the smaller diameter spheres, the PSF algorithm with TOF and single bed acquisition provided a comparatively better activity recovery. Quantification of Y-90 using Biograph mCT PET/CT is possible with a reasonable accuracy, the limitations being the size of the lesion and the activity concentration present. At this stage, based on our study, it seems advantageous to use different protocols depending on the size of the lesion.


Assuntos
Neoplasias Hepáticas/diagnóstico por imagem , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos , Tomografia Computadorizada por Raios X , Algoritmos , Calibragem , Humanos , Imageamento Tridimensional , Tomografia por Emissão de Pósitrons/normas , Compostos Radiofarmacêuticos/química , Sensibilidade e Especificidade , Tomografia Computadorizada por Raios X/normas , Radioisótopos de Ítrio/química
7.
AJR Am J Roentgenol ; 201(2): 419-26, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23883224

RESUMO

OBJECTIVE: The purpose of the study was to investigate the ability to predict survival, need for extracorporeal membrane oxygenation (ECMO), and incidence of chronic lung disease in patients with congenital diaphragmatic hernia in the context of a classification into three different times of gestation (< 28, 28-32, and > 32 weeks) by assessing the ratio between observed and expected MRI fetal lung volume. MATERIALS AND METHODS: The data analysis included 226 fetuses with congenital diaphragmatic hernia. MRI was performed at different times of gestation with a T2-weighted HASTE sequence. Receiver operating characteristic curve analysis was performed to investigate the prognostic value of assessment of the ratio between observed and expected MRI fetal lung volumes at different stages of fetal growth. RESULTS: For all reviewed times of gestation, the ratio between observed and expected MRI fetal lung volumes had almost equivalent statistically significant differences for neonatal survival (p ≤ 0.0029), need for ECMO therapy (p ≤ 0.0195), and development of chronic lung disease (p ≤ 0.0064). Results with high prognostic accuracy for early and for medium and late times in gestation also were obtained. Receiver operating characteristic analysis showed the highest area under the curve (≥ 0.819) for neonatal survival. CONCLUSION: In patients with congenital diaphragmatic hernia, the relation between observed and expected MRI fetal lung volume is a valuable prognostic parameter for predicting neonatal mortality, morbidity represented by the development of chronic lung disease, and the need for ECMO therapy in early gestation (< 28 weeks) as well as later gestation with no statistically significant differences.


Assuntos
Oxigenação por Membrana Extracorpórea , Hérnias Diafragmáticas Congênitas , Pneumopatias/diagnóstico , Imageamento por Ressonância Magnética/métodos , Adulto , Área Sob a Curva , Distribuição de Qui-Quadrado , Feminino , Hérnia Diafragmática/diagnóstico , Hérnia Diafragmática/terapia , Humanos , Recém-Nascido , Modelos Logísticos , Medidas de Volume Pulmonar , Masculino , Valor Preditivo dos Testes , Gravidez , Curva ROC , Índice de Gravidade de Doença , Taxa de Sobrevida
8.
Eur Heart J ; 34(10): 775-81, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22390914

RESUMO

AIMS: Perfusion-cardiac magnetic resonance (CMR) has emerged as a potential alternative to single-photon emission computed tomography (SPECT) to assess myocardial ischaemia non-invasively. The goal was to compare the diagnostic performance of perfusion-CMR and SPECT for the detection of coronary artery disease (CAD) using conventional X-ray coronary angiography (CXA) as the reference standard. METHODS AND RESULTS: In this multivendor trial, 533 patients, eligible for CXA or SPECT, were enrolled in 33 centres (USA and Europe) with 515 patients receiving MR contrast medium. Single-photon emission computed tomography and CXA were performed within 4 weeks before or after CMR in all patients. The prevalence of CAD in the sample was 49%. Drop-out rates for CMR and SPECT were 5.6 and 3.7%, respectively (P = 0.21). The primary endpoint was non-inferiority of CMR vs. SPECT for both sensitivity and specificity for the detection of CAD. Readers were blinded vs. clinical data, CXA, and imaging results. As a secondary endpoint, the safety profile of the CMR examination was evaluated. For CMR and SPECT, the sensitivity scores were 0.67 and 0.59, respectively, with the lower confidence level for the difference of +0.02, indicating superiority of CMR over SPECT. The specificity scores for CMR and SPECT were 0.61 and 0.72, respectively (lower confidence level for the difference: -0.17), indicating inferiority of CMR vs. SPECT. No severe adverse events occurred in the 515 patients. CONCLUSION: In this large multicentre, multivendor study, the sensitivity of perfusion-CMR to detect CAD was superior to SPECT, while its specificity was inferior to SPECT. Cardiac magnetic resonance is a safe alternative to SPECT to detect perfusion deficits in CAD.


Assuntos
Doença da Artéria Coronariana/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Angiografia por Ressonância Magnética/efeitos adversos , Angiografia por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Tomografia Computadorizada de Emissão de Fóton Único/efeitos adversos , Tomografia Computadorizada de Emissão de Fóton Único/métodos
10.
J Cardiovasc Magn Reson ; 14: 61, 2012 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-22938651

RESUMO

BACKGROUND: Perfusion-cardiovascular magnetic resonance (CMR) is generally accepted as an alternative to SPECT to assess myocardial ischemia non-invasively. However its performance vs gated-SPECT and in sub-populations is not fully established. The goal was to compare in a multicenter setting the diagnostic performance of perfusion-CMR and gated-SPECT for the detection of CAD in various populations using conventional x-ray coronary angiography (CXA) as the standard of reference. METHODS: In 33 centers (in US and Europe) 533 patients, eligible for CXA or SPECT, were enrolled in this multivendor trial. SPECT and CXA were performed within 4 weeks before or after CMR in all patients. Prevalence of CAD in the sample was 49% and 515 patients received MR contrast medium. Drop-out rates for CMR and SPECT were 5.6% and 3.7%, respectively (ns). The study was powered for the primary endpoint of non-inferiority of CMR vs SPECT for both, sensitivity and specificity for the detection of CAD (using a single-threshold reading), the results for the primary endpoint were reported elsewhere. In this article secondary endpoints are presented, i.e. the diagnostic performance of CMR versus SPECT in subpopulations such as multi-vessel disease (MVD), in men, in women, and in patients without prior myocardial infarction (MI). For diagnostic performance assessment the area under the receiver-operator-characteristics-curve (AUC) was calculated. Readers were blinded versus clinical data, CXA, and imaging results. RESULTS: The diagnostic performance (= area under ROC = AUC) of CMR was superior to SPECT (p = 0.0004, n = 425) and to gated-SPECT (p = 0.018, n = 253). CMR performed better than SPECT in MVD (p = 0.003 vs all SPECT, p = 0.04 vs gated-SPECT), in men (p = 0.004, n = 313) and in women (p = 0.03, n = 112) as well as in the non-infarct patients (p = 0.005, n = 186 in 1-3 vessel disease and p = 0.015, n = 140 in MVD). CONCLUSION: In this large multicenter, multivendor study the diagnostic performance of perfusion-CMR to detect CAD was superior to perfusion SPECT in the entire population and in sub-groups. Perfusion-CMR can be recommended as an alternative for SPECT imaging. TRIAL REGISTRATION: ClinicalTrials.gov, Identifier: NCT00977093.


Assuntos
Doença da Artéria Coronariana/diagnóstico , Circulação Coronária , Imagem Cinética por Ressonância Magnética/métodos , Isquemia Miocárdica/diagnóstico , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Doença da Artéria Coronariana/fisiopatologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Isquemia Miocárdica/fisiopatologia , Estudos Prospectivos , Curva ROC , Reprodutibilidade dos Testes , Índice de Gravidade de Doença
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