scholarly journals Συμβολή νεότερων τεχνικών μαγνητικού συντονισμού στη διάγνωση και παρακολούθηση του θεραπευτικού αποτελέσματος στον καρκίνο του προστάτη

2014 ◽  
Author(s):  
Αναστάσιος Γυφτόπουλος
Keyword(s):  
Multiparametric Mri ◽  
Dce Mri ◽  
Dynamic Contrast Enhanced ◽  
Contrast Enhanced

ΣΚΟΠΟΣ : Σκοπός της παρούσας διδακτορικής διατριβής ήταν η μελέτη ασθενών με διαγνωσμένο καρκίνο του προστάτη με νεότερες τεχνικές απεικόνισης (διάχυση (DWI), αιματική διήθηση), η συσχέτιση των απεικονιστικών με τα παθολογοανατομικά ευρήματα καθώς και η λειτουργική μελέτη του αδένα κατά τη διάρκεια της θεραπείας με σκοπό την εκτίμηση της ανταπόκρισης σε αυτή. Επιπρόσθετα η σύγκριση των παραμέτρων της πολυπαραμετρικής μαγνητικής τομογραφίας δηλαδή των ακολουθιών Τ2 προσανατολισμού, των ακολουθιών διάχυσης, της δυναμικής εξέτασης ή του συνδυασμού τους για την καλύτερη διάγνωση της κακοήθειας στον προστάτη.Σαν ελάχιστες προυποθέσεις για την πραγματοποίηση πολυπαραμετρικής Μαγνητικής Τομογραφίας είναι ο συνδυασμός ακολουθιών Τ1 και Τ2 προσανατολισμού με ακολουθίες διάχυσης (DWΙ) ή δυναμική εξέταση μετά χορήγηση παραμαγνητικής (dynamic contrast-enhanced MRΙ). ΥΛΙΚΟ-ΜΕΣΑ : Κατά τη διάρκεια των τελευταίων ετών της παρούσας μελέτης εξετάστηκαν στο Β’ Εργαστήριο Ακτινολογίας ασθενείς με υψηλά επίπεδα ειδικού προστατικού αντιγόνου (PSA) ορού αίματος στους οποίους είχε τεθεί η διάγνωση του καρκίνου του προστάτη με διορθική βιοψία. Τα παρακευάσματα των χειρουργηθέντων ασθενών τέμνονταν απο τον παθολογοανατόμο με εγκάρσιες τομές , σε αντιστοιχία με τα δεδομένα της εγκάρσιας ανατομίας όπως απεικονίζεται με την μαγνητική τομογραφία. Ορισμένοι ασθενείς υπεβλήθησαν σε ακτινοθεραπεία πραγματοποίησαν εξετάσεις πριν και μετά το πέρας της θεραπείας. ΑΠΟΤΕΛΕΣΜΑΤΑ: Η πολυπαραμετρική μελέτη είχε αυξημένη ευαισθησία ειδικότητα, μεγαλύτερη απο κάθε τεχνική ή συνδυασμό τους . Η αρνητική προγνωστική αξία του συνδυασμού των απεικονιστικών τεχνικών για την ανίχνευση του όγκου ήταν 88.3% . Η δυναμική εξέταση ( DCE ) είχε την υψηλότερη ευαισθησία στην μελέτη μας.Στη μελέτη μας φάνηκε οτι η ακτινοθεραπεία προκαλεί ελάττωση των τιμών στους χάρτες ADC απο τους πρώτους κύκλους θεραπείας. Το γεγονός αυτό συσχετίζεται με ανταπόκριση στη θεραπεία. Τα αποτελέσματα της ποσοτικής προσέγγισης αναδεικνύουν χαμηλότερες τιμές Τ2, ADC και υψηλότερες τιμές Ktrans στις περιοχές κακοήθειας με στατιστικά σημαντική διαφορά όσο αφορά τις δυο τελευταίες παραμέτρους. ΣΥΜΠΕΡΑΣΜΑ : Η πολυπαραμετρική Μαγνητική Τομογραφία (Multiparametric MRI) έχει την δυνατότητα να αλλάξει την συνηθισμένη διαγνωστική και θεραπευτική προσέγγιση της νόσου. Η προσθήκη τεχνικών όπως οι ακολουθίες διάχυσης (DWI), και η δυναμική μελέτη μετά την ενδοφλέβια χορήγηση παραμαγνητικής ουσίας (DCE-MRI) παρέχουν ανατομικές και λειτουργικές πληροφορίες και βοηθούν στον διαχωρισμό του φυσιολογικού απο τον παθολογικό ιστό. H πολυπαραμετρική μαγνητική τομογραφία είναι ένα εξαιρετικό εργαλείο για την διάγνωση ,τον καθορισμό της θεραπείας , την μελέτη του αποτελέσματός της καθώς και την παρακολούθηση των ασθενών με καρκίνο του προστάτη αδένα.

scholarly journals Perfusion in hand arthritis on dynamic contrast-enhanced computed tomography: a randomized prospective study using MRI as a standard of reference

2020 ◽  
Vol 50 (1) ◽  
pp. 59-68
Author(s):  
Sevtap Tugce Ulas ◽  
Kay Geert Hermann ◽  
Marcus R. Makowski ◽  
Robert Biesen ◽  
Fabian Proft ◽  
...  
Keyword(s):  
Rheumatoid Arthritis ◽  
Mean Transit Time ◽  
Region Of Interest ◽  
T Test ◽  
Dose Length Product ◽  
Suitable Alternative ◽  
Dce Mri ◽  
Dynamic Contrast Enhanced ◽  
Contrast Enhanced Ct ◽  
Contrast Enhanced

Abstract Objective To evaluate the performance of dynamic contrast-enhanced CT (DCE-CT) in detecting and quantitatively assessing perfusion parameters in patients with arthritis of the hand compared with dynamic contrast-enhanced MRI (DCE-MRI) as a standard of reference. Materials and methods In this IRB-approved randomized prospective single-centre study, 36 consecutive patients with suspected rheumatoid arthritis underwent DCE-CT (320-row, tube voltage 80 kVp, tube current 8.25 mAs) and DCE-MRI (1.5 T) of the hand. Perfusion maps were calculated separately for mean transit time (MTT), time to peak (TTP), relative blood volume (rBV), and relative blood flow (rBF) using four different decomposition techniques. Region of interest (ROI) analysis was performed in metacarpophalangeal joints II–V and in the wrist. Pairs of perfusion parameters in DCE-CT and DCE-MRI were compared using a two-tailed t test for paired samples and interpreted for effect size (Cohen’s d). According to the Rheumatoid Arthritis Magnetic Resonance Imaging Score (RAMRIS) scoring results, differentiation of synovitis-positive and synovitis-negative joints with both modalities was assessed with the independent t test. Results The two modalities yielded similar perfusion parameters. Identified differences had small effects (d 0.01–0.4). DCE-CT additionally differentiates inflamed and noninflamed joints based on rBF and rBV but tends to underestimate these parameters in severe inflammation. The total dose-length product (DLP) was 48 mGy*cm with an estimated effective dose of 0.038 mSv. Conclusion DCE-CT is a promising imaging technique in arthritis. In patients with a contraindication to MRI or when MRI is not available, DCE-CT is a suitable alternative to detect and assess arthritis.

scholarly journals Radiomic and Artificial Intelligence Analysis with Textural Metrics, Morphological and Dynamic Perfusion Features Extracted by Dynamic Contrast-Enhanced Magnetic Resonance Imaging in the Classification of Breast Lesions

2021 ◽  
Vol 11 (4) ◽  
pp. 1880
Author(s):  
Roberta Fusco ◽  
Adele Piccirillo ◽  
Mario Sansone ◽  
Vincenza Granata ◽  
Paolo Vallone ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Artificial Intelligence ◽  
Feature Selection ◽  
Resonance Imaging ◽  
Dynamic Features ◽  
Surgical Specimen ◽  
Dce Mri ◽  
Dynamic Contrast Enhanced ◽  
Contrast Enhanced ◽  
Malignant Lesions

Purpose: The aim of the study was to estimate the diagnostic accuracy of textural, morphological and dynamic features, extracted by dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) images, by carrying out univariate and multivariate statistical analyses including artificial intelligence approaches. Methods: In total, 85 patients with known breast lesion were enrolled in this retrospective study according to regulations issued by the local Institutional Review Board. All patients underwent DCE-MRI examination. The reference standard was pathology from a surgical specimen for malignant lesions and pathology from a surgical specimen or fine needle aspiration cytology, core or Tru-Cut needle biopsy for benign lesions. In total, 91 samples of 85 patients were analyzed. Furthermore, 48 textural metrics, 15 morphological and 81 dynamic parameters were extracted by manually segmenting regions of interest. Statistical analyses including univariate and multivariate approaches were performed: non-parametric Wilcoxon–Mann–Whitney test; receiver operating characteristic (ROC), linear classifier (LDA), decision tree (DT), k-nearest neighbors (KNN), and support vector machine (SVM) were utilized. A balancing approach and feature selection methods were used. Results: The univariate analysis showed low accuracy and area under the curve (AUC) for all considered features. Instead, in the multivariate textural analysis, the best performance (accuracy (ACC) = 0.78; AUC = 0.78) was reached with all 48 metrics and an LDA trained with balanced data. The best performance (ACC = 0.75; AUC = 0.80) using morphological features was reached with an SVM trained with 10-fold cross-variation (CV) and balanced data (with adaptive synthetic (ADASYN) function) and a subset of five robust morphological features (circularity, rectangularity, sphericity, gleaning and surface). The best performance (ACC = 0.82; AUC = 0.83) using dynamic features was reached with a trained SVM and balanced data (with ADASYN function). Conclusion: Multivariate analyses using pattern recognition approaches, including all morphological, textural and dynamic features, optimized by adaptive synthetic sampling and feature selection operations obtained the best results and showed the best performance in the discrimination of benign and malignant lesions.

scholarly journals Dynamic contrast-enhanced magnetic resonance imaging for monitoring neovascularization during bone regeneration—a randomized in vivo study in rabbits

2021 ◽  
Author(s):  
L. A. R. Righesso ◽  
M. Terekhov ◽  
H. Götz ◽  
M. Ackermann ◽  
T. Emrich ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Bone Regeneration ◽  
Blood Perfusion ◽  
Autogenous Bone ◽  
Resonance Imaging ◽  
Dce Mri ◽  
Dynamic Contrast Enhanced ◽  
Contrast Enhanced

Abstract Objectives Micro-computed tomography (μ-CT) and histology, the current gold standard methods for assessing the formation of new bone and blood vessels, are invasive and/or destructive. With that in mind, a more conservative tool, dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI), was tested for its accuracy and reproducibility in monitoring neovascularization during bone regeneration. Additionally, the suitability of blood perfusion as a surrogate of the efficacy of osteoplastic materials was evaluated. Materials and methods Sixteen rabbits were used and equally divided into four groups, according to the time of euthanasia (2, 3, 4, and 6 weeks after surgery). The animals were submitted to two 8-mm craniotomies that were filled with blood or autogenous bone. Neovascularization was assessed in vivo through DCE-MRI, and bone regeneration, ex vivo, through μ-CT and histology. Results The defects could be consistently identified, and their blood perfusion measured through DCE-MRI, there being statistically significant differences within the blood clot group between 3 and 6 weeks (p = 0.029), and between the former and autogenous bone at six weeks (p = 0.017). Nonetheless, no significant correlations between DCE-MRI findings on neovascularization and μ-CT (r =−0.101, 95% CI [−0.445; 0.268]) or histology (r = 0.305, 95% CI [−0.133; 0.644]) findings on bone regeneration were observed. Conclusions These results support the hypothesis that DCE-MRI can be used to monitor neovascularization but contradict the premise that it could predict bone regeneration as well.

scholarly journals The Use of Dynamic Contrast-Enhanced Magnetic Resonance Imaging for the Evaluation of Blood-Brain Barrier Disruption in Traumatic Brain Injury: What Is the Evidence?

2021 ◽  
Vol 11 (6) ◽  
pp. 775
Author(s):  
Sung-Suk Oh ◽  
Eun-Hee Lee ◽  
Jong-Hoon Kim ◽  
Young-Beom Seo ◽  
Yoo-Jin Choo ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Traumatic Brain Injury ◽  
Brain Injury ◽  
Magnetic Resonance ◽  
Blood Brain Barrier ◽  
Brain Barrier ◽  
Resonance Imaging ◽  
Dce Mri ◽  
Dynamic Contrast Enhanced ◽  
Contrast Enhanced

(1) Background: Blood brain barrier (BBB) disruption following traumatic brain injury (TBI) results in a secondary injury by facilitating the entry of neurotoxins to the brain parenchyma without filtration. In the current paper, we aimed to review previous dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) studies to evaluate the occurrence of BBB disruption after TBI. (2) Methods: In electronic databases (PubMed, Scopus, Embase, and the Cochrane Library), we searched for the following keywords: dynamic contrast-enhanced OR DCE AND brain injury. We included studies in which BBB disruption was evaluated in patients with TBI using DCE-MRI. (3) Results: Four articles were included in this review. To assess BBB disruption, linear fit, Tofts, extended Tofts, or Patlak models were used. KTrans and ve were increased, and the values of vp were decreased in the cerebral cortex and predilection sites for diffusion axonal injury. These findings are indicative of BBB disruption following TBI. (4) Conclusions: Our analysis supports the possibility of utilizing DCE-MRI for the detection of BBB disruption following TBI.

scholarly journals Correlation of radiomic features on dynamic contrast-enhanced magnetic resonance with microvessel density in hepatocellular carcinoma based on different models

2021 ◽  
Vol 49 (3) ◽  
pp. 030006052199758
Author(s):  
Hongwei Liang ◽  
Chunhong Hu ◽  
Jian Lu ◽  
Tao Zhang ◽  
Jifeng Jiang ◽  
...  
Keyword(s):  
Hepatocellular Carcinoma ◽  
Magnetic Resonance ◽  
Microvessel Density ◽  
Roc Analysis ◽  
Diagnostic Model ◽  
Model Parameters ◽  
Dce Mri ◽  
Dynamic Contrast Enhanced ◽  
Quantitative Parameters ◽  
Contrast Enhanced

Objective To explore the correlations of radiomic features of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) with microvessel density (MVD) in patients with hepatocellular carcinoma (HCC), based on single-input and dual-input two-compartment extended Tofts (SITET and DITET) models. Methods We compared the quantitative parameters of SITET and DITET models for DCE-MRI in 30 patients with HCC using paired sample t-tests. The correlations of SITET and DITET model parameters with CD31-MVD and CD34-MVD were analyzed using Pearson’s correlation analysis. A diagnostic model of CD34-MVD was established and the diagnostic abilities of models for MVD were analyzed using receiver operating characteristic curve (ROC) analysis. Results There were significant differences between the quantitative parameters in the two kinds of models. Compared with SITET, DITET parameters showed better correlations with CD31-MVD and CD34-MVD. The Ktrans and Ve radiomics features of the DITET model showed high efficiency for predicting the level of CD34-MVD according to ROC analysis, with areas under curves of 0.83 and 0.94, respectively. Conclusion Compared with SITET, the DITET model provides a better indication of the microcirculation of HCC and is thus more suitable for examining patients with HCC.

scholarly journals Dynamic contrast-enhanced MRI of synovitis in knee osteoarthritis: repeatability, discrimination and sensitivity to change in a prospective experimental study

2021 ◽  
Author(s):  
James W. MacKay ◽  
Faezeh Sanaei Nezhad ◽  
Tamam Rifai ◽  
Joshua D. Kaggie ◽  
Josephine H. Naish ◽  
...  
Keyword(s):  
Knee Osteoarthritis ◽  
Experimental Medicine ◽  
Sensitivity To Change ◽  
Dce Mri ◽  
Dynamic Contrast Enhanced Mri ◽  
Knee Oa ◽  
Dynamic Contrast Enhanced ◽  
Enhanced Mri ◽  
Contrast Enhanced ◽  
Contrast Enhanced Mri

Abstract Objectives Evaluate test-retest repeatability, ability to discriminate between osteoarthritic and healthy participants, and sensitivity to change over 6 months, of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) biomarkers in knee OA. Methods Fourteen individuals aged 40–60 with mild-moderate knee OA and 6 age-matched healthy volunteers (HV) underwent DCE-MRI at 3 T at baseline, 1 month and 6 months. Voxelwise pharmacokinetic modelling of dynamic data was used to calculate DCE-MRI biomarkers including Ktrans and IAUC60. Median DCE-MRI biomarker values were extracted for each participant at each study visit. Synovial segmentation was performed using both manual and semiautomatic methods with calculation of an additional biomarker, the volume of enhancing pannus (VEP). Test-retest repeatability was assessed using intraclass correlation coefficients (ICC). Smallest detectable differences (SDDs) were calculated from test-retest data. Discrimination between OA and HV was assessed via calculation of between-group standardised mean differences (SMD). Responsiveness was assessed via the number of OA participants with changes greater than the SDD at 6 months. Results Ktrans demonstrated the best test-retest repeatability (Ktrans/IAUC60/VEP ICCs 0.90/0.84/0.40, SDDs as % of OA mean 33/71/76%), discrimination between OA and HV (SMDs 0.94/0.54/0.50) and responsiveness (5/1/1 out of 12 OA participants with 6-month change > SDD) when compared to IAUC60 and VEP. Biomarkers derived from semiautomatic segmentation outperformed those derived from manual segmentation across all domains. Conclusions Ktrans demonstrated the best repeatability, discrimination and sensitivity to change suggesting that it is the optimal DCE-MRI biomarker for use in experimental medicine studies. Key Points • Dynamic contrast-enhanced MRI (DCE-MRI) provides quantitative measures of synovitis in knee osteoarthritis which may permit early assessment of efficacy in experimental medicine studies. • This prospective observational study compared DCE-MRI biomarkers across domains relevant to experimental medicine: test-retest repeatability, discriminative validity and sensitivity to change. • The DCE-MRI biomarker Ktransdemonstrated the best performance across all three domains, suggesting that it is the optimal biomarker for use in future interventional studies.

Abstract 5763: Dynamic Contrast-Enhanced MRI Detects Early Plaque Progression in a Rabbit Model of Atherosclerosis

Circulation ◽  
2008 ◽  
Vol 118 (suppl_18) ◽  
Author(s):  
William S Kerwin ◽  
Jerry Ricks ◽  
Michael Rosenfeld
Keyword(s):  
Vessel Wall ◽  
High Speed ◽  
Rabbit Model ◽  
Atherosclerotic Lesion ◽  
Intraplaque Hemorrhage ◽  
Slice Thickness ◽  
Dce Mri ◽  
Dynamic Contrast Enhanced ◽  
Contrast Enhanced ◽  
Plaque Inflammation

Recent studies have used dynamic contrast-enhanced (DCE) MRI to quantify the rate of uptake of gadolinium contrast agents in atherosclerotic plaque. The transfer constant K trans , that quantifies the blood supply and permeability of the plaque, shows strong association with plaque inflammation. The purpose of this study was to explore the link between K trans and plaque inflammation in a model of early atherosclerotic lesion development. Twelve NZW rabbits were placed on a 0.2% cholesterol diet and underwent balloon injury of the descending aorta. After 12 weeks, all rabbits underwent a DCE-MRI exam, after which 6 were euthanized and perfusion fixed to harvest the atherosclerotic aortas. The remaining 6 were imaged again at 24 weeks and their aortas were harvested. The DCE-MRI procedure utilized a unique, high-speed, small field-of-view imaging technique with quadruple inversion recovery blood suppression (turbo spin echo, TR=800 ms, TE=9ms, 3mm slice thickness, 0.5mm in-plane resolution). This allowed us to observe enhancement of the vessel wall without contamination from enhancement of the adjacent lumen. The DCE-MRI results were analyzed to determine the average, relative K trans in the vessel wall and compared to histological assessments of the aortas. K trans was significantly higher at 6 months compared to 3 months within the same animals (p<0.005) and compared to those euthanized at 3 months (p<0.001). No difference was observed between the two groups at 3 months (p=0.4). Histologically, aorta cross sections at 6 months had lesions that were no thicker than those at 3 months (0.49 vs. 0.45mm, p=0.6), but complex lesion features including necrotic cores, intraplaque hemorrhage, neovessels, and deep clusters of macrophages were significantly more common at 6 months (82% vs. 18%, p<0.001). The transformation of the lesions from simple to complex morphologies from 12 weeks to 24 coincided with a significant rise in K trans . We attribute this rise to the development of neovessels in response to pro-inflammatory stimuli. We conclude that K trans can be used to probe lesion characteristics and complexity in early atherosclerosis, with applications in early diagnosis and treatment monitoring. This research has received full or partial funding support from the American Heart Association, AHA Pacific/Mountain Affiliate (Alaska, Arizona, Colorado, Hawaii, Idaho, Montana, Oregon, Washington & Wyoming).

scholarly journals Dynamic Contrast-Enhanced Imaging as a Prognostic Tool in Early Diagnosis of Prostate Cancer: Correlation with PSA and Clinical Stage

2018 ◽  
Vol 2018 ◽  
pp. 1-7 ◽  
Author(s):  
Xingchen Wu ◽  
Petri Reinikainen ◽  
Mika Kapanen ◽  
Tuula Vierikko ◽  
Pertti Ryymin ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Prognostic Factors ◽  
Early Diagnosis ◽  
Early Stage ◽  
Clinical Stage ◽  
Specific Antigen ◽  
Transfer Constant ◽  
Dce Mri ◽  
Dynamic Contrast Enhanced ◽  
Contrast Enhanced

Background and Purpose. Although several methods have been developed to predict the outcome of patients with prostate cancer, early diagnosis of individual patient remains challenging. The aim of the present study was to correlate tumor perfusion parameters derived from dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and clinical prognostic factors and further to explore the diagnostic value of DCE-MRI parameters in early stage prostate cancer. Patients and Methods. Sixty-two newly diagnosed patients with histologically proven prostate adenocarcinoma were enrolled in our prospective study. Transrectal ultrasound-guided biopsy (12 cores, 6 on each lobe) was performed in each patient. Pathology was reviewed and graded according to the Gleason system. DCE-MRI was performed and analyzed using a two-compartmental model; quantitative parameters including volume transfer constant (Ktrans), reflux constant (Kep), and initial area under curve (iAUC) were calculated from the tumors and correlated with prostate-specific antigen (PSA), Gleason score, and clinical stage. Results. Ktrans (0.11 ± 0.02 min−1 versus 0.16 ± 0.06 min−1; p<0.05), Kep (0.38 ± 0.08 min−1 versus 0.60 ± 0.23 min−1; p<0.01), and iAUC (14.33 ± 2.66 mmoL/L/min versus 17.40 ± 5.97 mmoL/L/min; p<0.05) were all lower in the clinical stage T1c tumors (tumor number, n=11) than that of tumors in clinical stage T2 (n=58). Serum PSA correlated with both tumor Ktrans (r=0.304, p<0.05) and iAUC (r=0.258, p<0.05). Conclusions. Our study has confirmed that DCE-MRI is a promising biomarker that reflects the microcirculation of prostate cancer. DCE-MRI in combination with clinical prognostic factors may provide an effective new tool for the basis of early diagnosis and treatment decisions.

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