scholarly journals BIMG-04. MAPPING HETEROGENEITY OF HIGH-GRADE GLIOMA METABOLISM USING HIGH RESOLUTION 7T MRSI

2021 ◽  
Vol 3 (Supplement_1) ◽  
pp. i1-i1
Author(s):  
Gilbert Hangel ◽  
Cornelius Cadrien ◽  
Philipp Lazen ◽  
Sukrit Sharma ◽  
Julia Furtner ◽  
...  

Abstract OBJECTIVES Neurosurgical resection in gliomas depends on the precise preoperative definition of the tumor and its margins to realize a safe maximum resection that translates into a better patient outcome. New metabolic imaging techniques could improve this delineation as well as designate targets for biopsies. We validated the performance of our fast high-resolution whole-brain 3D-magnetic resonance spectroscopic imaging (MRSI) method at 7T in high-grade gliomas (HGGs) as first step to this regard. METHODS We measured 23 patients with HGGs at 7T with MRSI covering the whole cerebrum with 3.4mm isotropic resolution in 15 min. Quantification used a basis-set of 17 neurochemical components. They were evaluated for their reliability/quality and compared to neuroradiologically segmented tumor regions-of-interest (necrosis, contrast-enhanced, non-contrast-enhanced+edema, peritumoral) and histopathology (e.g., grade, IDH-status). RESULTS We found 18/23 measurements to be usable and ten neurochemicals quantified with acceptable quality. The most common denominators were increases of glutamine, glycine, and total choline as well as decreases of N-acetyl-aspartate and total creatine over most tumor regions. Other metabolites like taurine and serine showed mixed behavior. We further found that heterogeneity in the metabolic images often continued into the peritumoral region. While 2-hydroxy-glutarate could not be satisfyingly quantified, we found a tendency for a decrease of glutamate in IDH1-mutant HGGs. DISCUSSION Our findings corresponded well to clinical tumor segmentation but were more heterogeneous and often extended into the peritumoral region. Our results corresponded to previous knowledge, but with previously not feasible resolution. Apart from glycine/glutamine and their role in glioma progression, more research on the connection of glutamate and others to specific mutations is necessary. The addition of low-grade gliomas and statistical ROI analysis in a larger cohort will be the next important steps to define the benefits of our 7T MRSI approach for the definition of spatial metabolic tumor profiles.

2015 ◽  
Vol 1 ◽  
pp. 101-108 ◽  
Author(s):  
Naomi Jay ◽  
J. Michael Berry ◽  
Christine Miaskowski ◽  
Misha Cohen ◽  
Elizabeth Holly ◽  
...  

2020 ◽  
Author(s):  
Xinyue Ge ◽  
Zhong-Kai Lan ◽  
Jing Chen ◽  
Shang-Yong Zhu

Aim: The study retrospectively analysed the accuracy of preoperative contrast-enhanced ultrasound (CEUS) in differenti-ating stage Ta-T1 or low-grade bladder cancer (BC) from stage T2 or high-grade bladder cancer. Material and methods: We systematically searched the literature indexed in PubMed, Embase, and the Cochrane Library for original diagnostic articles of bladder cancer. The diagnostic accuracy of CEUS was compared with cystoscopy and/or transurethral resection of bladder tumors (TURBT). The bivariate logistic regression model was used for data pooling, couple forest plot, diagnostic odds ratio (DOR) and summary receiver operating characteristic (SROC). Results: Five studies met the selection criteria; the overall number of reported bladder cancers patients were 436. The pooled-sensitivity (P-SEN), pooled-specificity (P-SPE), pooled-positive likelihood ratio (PLR+), pooled-negative likelihood ratio (PLR−), DOR, and area under the SROC curve were 94.0% (95%CI: 85%–98%), 90% (95%CI: 83%–95%), 9.5 (95%CI: 5.1–17.6), 0.06 (95%CI: 0.02–0.17), 147 (95%CI: 35–612) and 97% (95% CI: 95%–98%) respectively. Conclusion: CEUS reaches a high efficiency in discriminating Ta-T1 or low-grade bladder cancer from stage T2 or high-grade bladder cancer. It can be a promising method in patients to distinguish T staging and grading of bladder cancer because of its high sensitivity, specificity and diagnostic accuracy.


2021 ◽  
pp. 21-24
Author(s):  
A. V. Fedorova ◽  
N. V. Kochergina ◽  
A. B. Bludov ◽  
I. V. Boulycheva ◽  
E. A. Sushentsov ◽  
...  

Purpose. Determining the diagnostic value of magnetic resonance imaging in the accurate definition of chondrosarcoma of bone grade at the pre-surgery examination. Material and methods. We analyzed examination data (magnetic resonance imaging with no contrast enhancement) of 70 patients with chondrosarcoma (35 patients with low-grade chondrosarcoma and 35 patients with high grade chondrosarcoma). Informative weighted coefficients were determined separately for ‘learning’ and ‘examination’ samples. On the basis of weighted coefficients, the decisive rule was created for differentiation between low-grade and high-grade chondrosarcoma. Results. The sensitivity of the method was 87.0%, specificity was 95.6%, total correct classification was 91.03%. Conclusion. Magnetic resonance imaging is a highly informative method for prediction of chondrosarcoma grade at the pre-surgery examination.


2015 ◽  
Vol 41 (1-2) ◽  
pp. 87-95 ◽  
Author(s):  
Luca Petrone ◽  
Stefania Nannoni ◽  
Alessandra Del Bene ◽  
Vanessa Palumbo ◽  
Domenico Inzitari

Background: In 1989, Louis Caplan first used the term branch atheromatous disease (BAD) to describe an occlusion or stenosis at the origin of a deep penetrating artery of the brain, associated with a microatheroma or a junctional plaque, and leading to an internal capsule or pontine small infarct. BAD remained an understudied concept for decades. In recent years, the increasing diffusion of high-resolution magnetic resonance imaging (HRMRI) techniques brought new attention to the BAD debate. We have reviewed clinical studies dealing with BAD-related stroke checking whether a univocal definition of BAD existed, as well as to what extent were consistently associated clinical and imaging features reported. Summary: We conducted a search of the available literature published up to October 20, 2015 via PubMed using the following search terms: ‘branch atheromatous disease,' ‘intracranial branch atheromatous disease,' ‘cerebral branch atheromatous disease,' combined with ‘stroke.' Forty-six articles were included. We found discrepant definitions and a large variation among clinical features reported in BAD-related stroke patients: among others, a consistent association between BAD and any specific vascular risk factor profile was not detected. Despite this, early neurological deterioration (END) was consistently reported to occur frequently in such patients, although no clear-cut rate range or specific predictor or mechanism of progression was established. In a majority of the studies reporting imaging data, BAD diagnosis was not based on the selective site or type of arterial walls changes, but was inferred based on the vascular territory, size and/or shape of the ischemic lesion. Following the concept that these changes are seated proximally along the perforator artery, differently from to lipohyalinosis changes located distally, the consequent ischemic lesion was hypothesized to be larger in BAD than in lacunar infarcts. However, across reviewed studies, there was little consistency on the dimensional cutoff used to define BAD-related infarcts. In the last few years, a still limited number of studies using HRMRI techniques is providing preliminary proofs that atheromatous changes causing selective remodeling in the parent vessel and extending through the proximal segment of perforating vessel may subtend BAD. Key Messages: Our literature search showed the lack of a clear-cut definition of BAD, although BAD-related strokes were consistently considered a high risk of END. The use of high-resolution imaging techniques in the assessment of small subcortical strokes may represent the cornerstone in the perspective to better delimiting the boundaries of BAD as a nosological entity.


2014 ◽  
Vol 2014 ◽  
pp. 1-11 ◽  
Author(s):  
Kazuhiko Ueda ◽  
Osamu Matsui ◽  
Azusa Kitao ◽  
Satoshi Kobayashi ◽  
Jun Nakayama ◽  
...  

Tumor hemodynamics of carcinogenic hepatocytes nodules, that is, low grade dysplastic nodules, high grade dysplastic nodules, early hepatocellular carcinomas (HCCs), and progressed HCCs, change during multistep dedifferentiation of the nodules. Morphometric analyses of inflow vessels of these nodules indicate that the portal veins of carcinogenic hepatocyte nodules monotonically decrease whereas the arteries bitonically change, first decrease and then increase. Findings on imaging techniques depicting these changes in tumor blood inflows, especially intra-arterial contrast-enhanced computed tomography, closely related not only to the histological differentiation of the nodules but also to the outcomes of the nodules. Histological analyses of connections between the vessels within the tumors and those in the surrounding livers and findings on imaging techniques indicate that drainage vessels of HCC change from hepatic veins to hepatic sinusoids and then to portal veins during multistep hepatocarcinogenesis. Understanding of tumor hemodynamics through radio-pathological correlations will be helpful in drawing up therapeutic strategies for carcinogenic hepatocyte nodules arising in cirrhosis.


2020 ◽  
pp. 20200699
Author(s):  
Lin Jia ◽  
Xia Wu ◽  
Qian Wan ◽  
Liwen Wan ◽  
Wenxiao Jia ◽  
...  

Objective: To evaluate the effect of artery input function (AIF) derived from different arteries for pharmacokinetic modeling on dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) parameters in the grading of gliomas. Methods: 49 patients with pathologically confirmed gliomas were recruited and underwent DCE-MRI. A modified Tofts model with different AIFs derived from anterior cerebral artery (ACA), ipsilateral and contralateral middle cerebral artery (MCA) and posterior cerebral artery (PCA) was used to estimate quantitative parameters such as Ktrans (volume transfer constant) and Ve (fractional extracellular-extravascular space volume) for distinguishing the low grade glioma from high grade glioma. The Ktrans and Ve were compared between different arteries using Two Related Samples Tests (TRST) (i.e. Wilcoxon Signed Ranks Test). In addition, these parameters were compared between the low and high grades as well as between the grade II and III using the Mann-Whitney U-test. A p-value of less than 0.05 was regarded as statistically significant. Results: All the patients completed the DCE-MRI successfully. Sharp wash-in and wash-out phases were observed in all AIFs derived from the different arteries. The quantitative parameters (Ktrans and Ve) calculated from PCA were significant higher than those from ACA and MCA for low and high grades, respectively (p < 0.05). Despite the differences of quantitative parameters derived from ACA, MCA and PCA, the Ktrans and Ve from any AIFs could distinguish between low and high grade, however, only Ktrans from any AIFs could distinguish grades II and III. There was no significant correlation between parameters and the distance from the artery, which the AIF was extracted, to the tumor. Conclusion: Both quantitative parameters Ktrans and Ve calculated using any AIF of ACA, MCA, and PCA can be used for distinguishing the low- from high-grade gliomas, however, only Ktrans can distinguish grades II and III. Advances in knowledge: We sought to assess the effect of AIF on DCE-MRI for determining grades of gliomas. Both quantitative parameters Ktrans and Ve calculated using any AIF of ACA, MCA, and PCA can be used for distinguishing the low- from high-grade gliomas.


2019 ◽  
pp. 1-9 ◽  
Author(s):  
Jonathan Shapey ◽  
Guotai Wang ◽  
Reuben Dorent ◽  
Alexis Dimitriadis ◽  
Wenqi Li ◽  
...  

OBJECTIVEAutomatic segmentation of vestibular schwannomas (VSs) from MRI could significantly improve clinical workflow and assist in patient management. Accurate tumor segmentation and volumetric measurements provide the best indicators to detect subtle VS growth, but current techniques are labor intensive and dedicated software is not readily available within the clinical setting. The authors aim to develop a novel artificial intelligence (AI) framework to be embedded in the clinical routine for automatic delineation and volumetry of VS.METHODSImaging data (contrast-enhanced T1-weighted [ceT1] and high-resolution T2-weighted [hrT2] MR images) from all patients meeting the study’s inclusion/exclusion criteria who had a single sporadic VS treated with Gamma Knife stereotactic radiosurgery were used to create a model. The authors developed a novel AI framework based on a 2.5D convolutional neural network (CNN) to exploit the different in-plane and through-plane resolutions encountered in standard clinical imaging protocols. They used a computational attention module to enable the CNN to focus on the small VS target and propose a supervision on the attention map for more accurate segmentation. The manually segmented target tumor volume (also tested for interobserver variability) was used as the ground truth for training and evaluation of the CNN. We quantitatively measured the Dice score, average symmetric surface distance (ASSD), and relative volume error (RVE) of the automatic segmentation results in comparison to manual segmentations to assess the model’s accuracy.RESULTSImaging data from all eligible patients (n = 243) were randomly split into 3 nonoverlapping groups for training (n = 177), hyperparameter tuning (n = 20), and testing (n = 46). Dice, ASSD, and RVE scores were measured on the testing set for the respective input data types as follows: ceT1 93.43%, 0.203 mm, 6.96%; hrT2 88.25%, 0.416 mm, 9.77%; combined ceT1/hrT2 93.68%, 0.199 mm, 7.03%. Given a margin of 5% for the Dice score, the automated method was shown to achieve statistically equivalent performance in comparison to an annotator using ceT1 images alone (p = 4e−13) and combined ceT1/hrT2 images (p = 7e−18) as inputs.CONCLUSIONSThe authors developed a robust AI framework for automatically delineating and calculating VS tumor volume and have achieved excellent results, equivalent to those achieved by an independent human annotator. This promising AI technology has the potential to improve the management of patients with VS and potentially other brain tumors.


2019 ◽  
Vol 19 (1) ◽  
Author(s):  
Yuan Yuan ◽  
Luguang Chen ◽  
Shengnan Ren ◽  
Zhen Wang ◽  
Yukun Chen ◽  
...  

Abstract Background To investigate and compare the diagnostic performance in T staging for patients with esophagogastric junction cancer using high-resolution magnetic resonance imaging (HR MRI), as compared with conventional MRI at 3 Tesla. Methods A total of 118 patients with pathologically confirmed esophagogastric junction cancer were included and underwent multiparameter HR MRI (Cohort 1, 62 patients) or conventional MRI (Cohort 2, 56 patients). T2-weighted, T1-weighted, diffusion-weighted and contrast-enhanced T1-weighted images of each patient were evaluated by two radiologists who determined the preoperative T staging by consensus. Using pathologic staging as the gold standard, the consistency between HR MRI and pathology and between conventional MRI and pathology in T staging was calculated and compared. The overall accuracy, overstatement and understatement of HR MRI and conventional MRI in T staging of patients with esophagogastric junction cancer were computed and compared. Moreover, the diagnostic performance of HR MRI and conventional MRI in T staging (≤ T1 and ≥ T4) of patients with esophagogastric junction cancer were evaluated. Results There were no significant differences in age (p = 0.465) and sex (p = 0.175) between Cohorts 1 and 2. Excellent agreement was observed in the T staging of patients with esophagogastric junction cancer between pathology and HR MRI (kappa = 0.813), while moderate agreement was observed between pathology and conventional MRI (kappa = 0.486). Significant differences were observed in overall accuracy (88.7% vs 64.3%, p = 0.002) and understatement (1.6% vs 26.8%, p < 0.001) but not for overstatement (9.7% vs 8.9%, p = 0.889) in T staging between HR MRI and conventional MRI techniques. For differentiating the T stages of ≤ T1 from ≥ T2 and the T stages of ≤ T3 from ≥ T4, no significant differences were observed between the imaging techniques. Conclusions HR MRI has good diagnostic performance and may serve as an alternative technique in the T staging of patients with esophagogastric junction cancer in clinical practice.


2019 ◽  
Vol 8 (5) ◽  
pp. 650 ◽  
Author(s):  
Carlo Luca Romanò ◽  
Hazem Al Khawashki ◽  
Thami Benzakour ◽  
Svetlana Bozhkova ◽  
Hernán del Sel ◽  
...  

The definition of peri-prosthetic joint infection (PJI) has a strong impact on the diagnostic pathway and on treatment decisions. In the last decade, at least five different definitions of peri-prosthetic joint infection (PJI) have been proposed, each one with intrinsic limitations. In order to move a step forward, the World Association against Infection in Orthopedics and Trauma (W.A.I.O.T.) has studied a possible alternative solution, based on three parameters: 1. the relative ability of each diagnostic test or procedure to Rule OUT and/or to Rule IN a PJI; 2. the clinical presentation; 3. the distinction between pre/intra-operative findings and post-operative confirmation. According to the WAIOT definition, any positive Rule IN test (a test with a specificity > 90%) scores +1, while a negative Rule OUT test (a test with a sensitivity > 90%) scores −1. When a minimum of two Rule IN and two Rule OUT tests are performed in a given patient, the balance between positive and negative tests, interpreted in the light of the clinical presentation and of the post-operative findings, allows to identify five different conditions: High-Grade PJI (score ≥ 1), Low-Grade PJI (≥0), Biofilm-related implant malfunction, Contamination and No infection (all scoring < 0). The proposed definition leaves the physician free to choose among different tests with similar sensitivity or specificity, on the basis of medical, logistical and economic considerations, while novel tests or diagnostic procedures can be implemented in the definition at any time, provided that they meet the required sensitivity and/or specificity thresholds. Key procedures to confirm or to exclude the diagnosis of PJI remain post-operative histological and microbiological analysis; in this regard, given the biofilm-related nature of PJI, microbiological investigations should be conducted with proper sampling, closed transport systems, antibiofilm processing of tissue samples and explanted biomaterials, and prolonged cultures. The proposed WAIOT definition is the result of an international, multidisciplinary effort. Next step will be a large scale, multicenter clinical validation trial.


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