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1.
World J Urol ; 42(1): 19, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38197902

RESUMO

OBJECTIVES: To determine a data-based optimal annual radical cystectomy (RC) hospital volume threshold and evaluate its clinical significance regarding perioperative mortality, complications, length of hospital stay, and hospital revenues. MATERIAL AND METHODS: We used the German Nationwide inpatient Data, provided by the Research Data Center of the Federal Bureau of Statistics (2005-2020). 95,841 patients undergoing RC were included. Based on ROC analyses, the optimal RC threshold to reduce mortality, ileus, sepsis, transfusion, hospital stay, and costs is 54, 50, 44, 44, 71 and 76 cases/year, respectively. Therefore, we defined an optimal annual hospital threshold of 50 RCs/year, and we also used the threshold of 20 RCs/year proposed by the EAU guidelines to perform multiple patient-level analyses. RESULTS: 28,291 (29.5%) patients were operated in low- (< 20 RC/year), 49,616 (51.8%) in intermediate- (20-49 RC/year), and 17,934 (18.7%) in high-volume (≥ 50 RC/year) centers. After adjusting for major risk factors, high-volume centers were associated with lower inpatient mortality (OR 0.72, 95% CI 0.64-0.8, p < 0.001), shorter length of hospital stay (2.7 days, 95% CI 2.4-2.9, p < 0.001) and lower costs (457 Euros, 95% CI 207-707, p < 0.001) compared to low-volume centers. Patients operated in low-volume centers developed more perioperative complications such as transfusion, sepsis, and ileus. CONCLUSIONS: Centralization of RC not only improves inpatient morbidity and mortality but also reduces hospital stay and costs. We propose a threshold of 50 RCs/year for optimal outcomes.


Assuntos
Íleus , Sepse , Neoplasias da Bexiga Urinária , Humanos , Pacientes Internados , Cistectomia , Neoplasias da Bexiga Urinária/cirurgia , Hospitais , Morbidade , Sepse/epidemiologia
2.
Diagnostics (Basel) ; 12(3)2022 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-35328138

RESUMO

(1) Background: To assess the treatment response of benign prostatic syndrome (BPS) following prostatic artery embolization (PAE) using a semi-automatic software analysis of magnetic resonance imaging (MRI) features and clinical indexes. (2) Methods: Prospective, monocenter study of MRI and clinical data of n = 27 patients with symptomatic BPS before and (1, 6, 12 months) after PAE. MRI analysis was performed using a dedicated semi-automatic software for segmentation of the central and the total gland (CG, TG), respectively; signal intensities (SIs) of T1-weighted (T1w), T2-weighted (T2w), and diffusion-weighted images (DWI), as well as intravesical prostatic protrusion (IPP) and prostatic volumes (CGV, TGV), were evaluated at each time point. The semi-automatic assessed TGV was compared to conventional TGV by an ellipse formula. International prostate symptom score (IPSS) and international consultation on incontinence questionnaire−urinary incontinence short form (ICIQ-UI SF) questionnaires were used as clinical indexes. Statistical testing in the form of ANOVA, pairwise comparisons using Bonferroni correction, and multiple linear correlations, were conducted using SPSS. (3) Results: TGV was significantly reduced one, six, and 12 months after PAE as assessed by the semi-automatic approach and conventional ellipse formula (p = 0.005; p = 0.025). CGV significantly decreased after one month (p = 0.038), but showed no significant differences six and 12 months after PAE (p = 0.191; p = 0.283). IPP at baseline was demonstrated by 25/27 patients (92.6%) with a significant decrease one, six, and 12 months after treatment (p = 0.028; p = 0.010; p = 0.008). Significant improvement in IPSS and ICIQ-UI SF (p = 0.002; p = 0.016) after one month correlated moderately with TGV reduction (p = 0.031; p = 0.05, correlation coefficients 0.52; 0.69). Apparent diffusion coefficient (ADC) values of CG significantly decreased one month after embolization (p < 0.001), while there were no significant differences in T1w and T2w SIs before and after treatment at each time point. (4) Conclusions: The semi-automatic approach is appropriate for the assessment of volumetric and morphological changes in prostate MRI following PAE, able to identify significantly different ADC values post-treatment without the need for manual identification of infarct areas. Semi-automatic measured TGV reduction is significant and comparable to the TGV calculated by the conventional ellipse formula, confirming the clinical response after PAE.

3.
Eur Radiol ; 32(2): 1117-1126, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34455484

RESUMO

OBJECTIVES: To investigate the cost-effectiveness of supplemental short-protocol brain MRI after negative non-contrast CT for the detection of minor strokes in emergency patients with mild and unspecific neurological symptoms. METHODS: The economic evaluation was centered around a prospective single-center diagnostic accuracy study validating the use of short-protocol brain MRI in the emergency setting. A decision-analytic Markov model distinguished the strategies "no additional imaging" and "additional short-protocol MRI" for evaluation. Minor stroke was assumed to be missed in the initial evaluation in 40% of patients without short-protocol MRI. Specialized post-stroke care with immediate secondary prophylaxis was assumed for patients with detected minor stroke. Utilities and quality-of-life measures were estimated as quality-adjusted life years (QALYs). Input parameters were obtained from the literature. The Markov model simulated a follow-up period of up to 30 years. Willingness to pay was set to $100,000 per QALY. Cost-effectiveness was calculated and deterministic and probabilistic sensitivity analysis was performed. RESULTS: Additional short-protocol MRI was the dominant strategy with overall costs of $26,304 (CT only: $27,109). Cumulative calculated effectiveness in the CT-only group was 14.25 QALYs (short-protocol MRI group: 14.31 QALYs). In the deterministic sensitivity analysis, additional short-protocol MRI remained the dominant strategy in all investigated ranges. Probabilistic sensitivity analysis results from the base case analysis were confirmed, and additional short-protocol MRI resulted in lower costs and higher effectiveness. CONCLUSION: Additional short-protocol MRI in emergency patients with mild and unspecific neurological symptoms enables timely secondary prophylaxis through detection of minor strokes, resulting in lower costs and higher cumulative QALYs. KEY POINTS: • Short-protocol brain MRI after negative head CT in selected emergency patients with mild and unspecific neurological symptoms allows for timely detection of minor strokes. • This strategy supports clinical decision-making with regard to immediate initiation of secondary prophylactic treatment, potentially preventing subsequent major strokes with associated high costs and reduced QALY. • According to the Markov model, additional short-protocol MRI remained the dominant strategy over wide variations of input parameters, even when assuming disproportionally high costs of the supplemental MRI scan.


Assuntos
Imageamento por Ressonância Magnética , Tomografia Computadorizada por Raios X , Encéfalo/diagnóstico por imagem , Análise Custo-Benefício , Humanos , Estudos Prospectivos , Anos de Vida Ajustados por Qualidade de Vida
4.
Neuroimage Clin ; 24: 101949, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31398553

RESUMO

OBJECTIVES: Many predictive or influencing factors have emerged in investigations of the cognitive reserve model of patients with Alzheimer's disease (AD). For example, neuronal injury, which correlates with cognitive decline in AD, can be assessed by [18F]-fluorodeoxyglucose positron-emission-tomography (FDG-PET), structural magnetic resonance imaging (MRI) and total tau in cerebrospinal fluid (CSFt-tau), all according to the A/T/N-classification. The aim of this study was to calculate residual cognitive performance based on neuronal injury biomarkers as a surrogate of cognitive reserve, and to test the predictive value of this index for the individual clinical course. METHODS: 110 initially mild cognitive impaired and demented subjects (age 71 ±â€¯8 years) with a final diagnosis of AD dementia were assessed at baseline by clinical mini-mental-state-examination (MMSE), FDG-PET, MRI and CSFt-tau. All neuronal injury markers were tested for an association with clinical MMSE and the resulting residuals were correlated with years of education. We used multiple regression analysis to calculate the expected MMSE score based on neuronal injury biomarkers and covariates. The residuals of the partial correlation for each biomarker and the predicted residualized memory function were correlated with individual cognitive changes measured during clinical follow-up (27 ±â€¯13 months). RESULTS: FDG-PET correlated highly with clinical MMSE (R = -0.49, p < .01), whereas hippocampal atrophy to MRI (R = -0.15, p = .14) and CSFt-tau (R = -0.12, p = .22) showed only weak correlations. Residuals of all neuronal injury biomarker regressions correlated significantly with education level, indicating them to be surrogates of cognitive reserve. A positive residual was associated with faster cognitive deterioration at follow-up for the residuals of stand-alone FDG-PET (R = -0.36, p = .01) and the combined residualized memory function model (R = -0.35, p = .02). CONCLUSIONS: These findings suggest that subjects with higher cognitive reserve had accumulated more pathology, which subsequently caused a faster cognitive decline over time. Together with previous findings suggesting that higher reserve is associated with slower cognitive decline, we propose a biphasic reserve effect, with an initially protective phase followed by more rapid decompensation once the protection is overwhelmed.


Assuntos
Doença de Alzheimer/líquido cefalorraquidiano , Doença de Alzheimer/diagnóstico por imagem , Disfunção Cognitiva/líquido cefalorraquidiano , Disfunção Cognitiva/diagnóstico por imagem , Reserva Cognitiva/fisiologia , Proteínas tau/líquido cefalorraquidiano , Idoso , Doença de Alzheimer/metabolismo , Biomarcadores/líquido cefalorraquidiano , Biomarcadores/metabolismo , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Disfunção Cognitiva/metabolismo , Feminino , Fluordesoxiglucose F18 , Seguimentos , Humanos , Imageamento por Ressonância Magnética/tendências , Masculino , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons/tendências
5.
Invest Radiol ; 51(11): 746-755, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27082316

RESUMO

OBJECTIVES: The aim of this study was to investigate magnetic resonance imaging (MRI) with αvß3-integrin-targeted ultrasmall superparamagnetic iron oxide nanoparticles (RGD-USPIO) for the in vivo monitoring of early antiangiogenic therapy effects in experimental breast cancer. MATERIALS AND METHODS: Orthotopic human breast cancer (MDA-MB-231) xenograft-bearing severe combined immunodeficiency mice were imaged before and after a 1-week therapy with the vascular endothelial growth factor receptor-antibody bevacizumab or placebo (n = 10 per group, daily intraperitoneal injections of bevacizumab or a volume-equivalent placebo solution, respectively) on a clinical 3 T scanner (Magnetom Skyra; Siemens Healthcare, Erlangen, Germany) before and 60 minutes after the intravenous injection of RGD-USPIO (P04000; Guerbet, Villepinte, France). R2 relaxometry employing a T2-weighted spin-echo sequence with 4 echo times (echo time, 20/40/60/80 milliseconds; repetition time, 3800 milliseconds; matrix, 128 × 128; field of view, 50 × 50; slice thickness, 1.2 mm; time to acquisition, 25 minutes) was used as semiquantitative measure to determine RGD-USPIO endothelial binding. In addition, the T2-weighted images were used to perform volumetric tumor response assessments. Imaging results were validated by ex vivo multiparametric immunohistochemistry with regard to αvß3-integrin expression, microvascular density (CD31), proliferation (Ki-67), and apoptosis (TUNEL). RESULTS: RGD-USPIO endothelial binding was significantly reduced after vascular endothelial growth factor inhibition, compared with the control group in which an increased endothelial binding was detected ([INCREMENT]R2Therapy = -0.80 ± 0.78 s; [INCREMENT]R2Control = +0.27 ± 0.59 s; P = 0.002). Correspondingly, immunohistochemistry revealed a significantly lower αvß3-integrin expression (91 ± 30 vs 357 ± 72; P < 0.001), microvascular density (CD31, 109 ± 46 vs 440 ± 208; P < 0.001), tumor cell proliferation (Ki-67, 4040 ± 1373 vs 6530 ± 1217; P < 0.001), as well as significantly higher apoptosis (TUNEL, 11186 ± 4387 vs 4017 ± 1191; P = 0.004) in the therapy compared with the control group. Contrary to the changes in αvß3-integrin expression detected by RGD-USPIO MRI, morphology-based tumor response assessments did not show a significant intergroup difference in tumor volume development over the course of the experiment (ΔVolTherapy +71 ± 40 µL vs ΔVolControl +125 ± 81 µL; P > 0.05). CONCLUSIONS: RGD-USPIO MRI allows for the noninvasive assessment of αvß3-integrin expression in the investigated breast cancer model. RGD-USPIO MRI may be applicable for the in vivo monitoring of early antiangiogenic therapy effects in experimental breast cancer, generating possible complementary molecular imaging biomarkers to morphology-based tumor response assessments.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Bevacizumab/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Meios de Contraste , Integrina alfaVbeta3 , Imageamento por Ressonância Magnética/métodos , Animais , Dextranos , Modelos Animais de Doenças , Feminino , Xenoenxertos , Humanos , Nanopartículas de Magnetita , Camundongos , Resultado do Tratamento
6.
Invest Radiol ; 49(11): 720-7, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24901546

RESUMO

OBJECTIVES: The aim of this study was to compare single-slice and 3-dimensional (3D) analysis for magnetic resonance renography (plasma flow [FP], plasma volume [VP], and glomerular filtration rate [GFR]) and for dynamic contrast-enhanced magnetic resonance imaging (MRI) of renal tumors (FP, VP, permeability-surface area product), respectively. MATERIAL AND METHODS: We prospectively included 22 patients (43 kidneys with 22 suspicious renal lesions) and performed preoperative and postoperative imaging before and after partial nephrectomy, respectively. Of the 22 renal lesions, 15 turned out to be renal cell carcinoma and were included in the tumor analysis, altogether leading to 86 renal and 15 tumor MRI scans, respectively. Dynamic contrast-enhanced MRI was performed with a time-resolved angiography with stochastic trajectories sequence (spatial resolution, 2.6 × 2.6 × 2.6 mm3; temporal resolution, 2.5 seconds) at 3 T (Magnetom Verio; Siemens Healthcare Sector) after injection of 0.05 mmol/kg body weight Gadobutrol (Bayer Healthcare Pharmaceuticals). Analysis was performed using regions of interest encompassing a single central slice and the whole kidney/tumor, respectively. A 2-compartment model yielding FP, VP, GFR, or tumor permeability-surface area product was used for kinetic modelling. Modelling was performed based on relative contrast enhancement to account for coil-related inhomogeneity. Significance in difference, agreement, and goodness of fit of the data to the curve was assessed with paired t tests, Bland-Altman plots, and χ2 test, respectively. RESULTS: Bland-Altman analysis revealed a good agreement between both types of measurement for kidneys and tumors, respectively. Results between single-slice and whole-kidney regions of interest showed significant differences for Fp (single slice, 256.1 ± 104.1 mL/100 mL/min; whole kidney, 217.2 ± 92.5 mL/100 mL/min; P < 0.01). Regarding VP and GFR, no significant differences were observed. The χ2 test showed a significantly better goodness of fit of the data to the curve for whole kidneys (0.30% ± 0.18%) than for single slices (0.43% ± 0.26%) (P < 0.01). In contrast to renal assessment, tumor analysis showed no significant differences regarding functional parameters and χ test, respectively. CONCLUSION: In dynamic contrast-enhanced MRI of the kidney, both 3D whole-organ/tumor and single-slice analyses provide roughly comparable values in functional analysis. However, 3D assessment is considerably more precise and should be preferred if available.


Assuntos
Carcinoma de Células Renais/diagnóstico , Meios de Contraste , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Neoplasias Renais/diagnóstico , Imageamento por Ressonância Magnética/métodos , Feminino , Taxa de Filtração Glomerular , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Rim/patologia , Nefropatias/diagnóstico , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Sensibilidade e Especificidade
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