Search results for "Image Interpretation"
showing 10 items of 201 documents
SPM-based count normalization provides excellent discrimination of mild Alzheimer's disease and amnestic mild cognitive impairment from healthy aging☆
2008
Statistical comparisons of [(18)F]FDG PET scans between healthy subjects and patients with Alzheimer's disease (AD) or amnestic mild cognitive impairment (aMCI) using Statistical Parametric Mapping (SPM) usually require normalization of regional tracer uptake via ROIs defined using additional software. Here, we validate a simple SPM-based method for count normalization. FDG PET scans of 21 mild, 15 very mild AD, 11 aMCI patients and 15 age-matched controls were analyzed. First, we obtained relative increases in the whole patient sample compared to controls (i.e. areas relatively preserved in patients) with proportional scaling to the cerebral global mean (CGM). Next, average absolute counts…
Early evaluation using a radiomic signature of unresectable hepatic metastases to predict outcome in patients with colorectal cancer treated with FOL…
2020
PurposeThe objective of this study was to build and validate a radiomic signature to predict early a poor outcome using baseline and 2-month evaluation CT and to compare it to the RECIST1·1 and morphological criteria defined by changes in homogeneity and borders.MethodsThis study is an ancillary study from the PRODIGE-9 multicentre prospective study for which 491 patients with metastatic colorectal cancer (mCRC) treated by 5-fluorouracil, leucovorin and irinotecan (FOLFIRI) and bevacizumab had been analysed. In 230 patients, computed texture analysis was performed on the dominant liver lesion (DLL) at baseline and 2 months after chemotherapy. RECIST1·1 evaluation was performed at 6 months. …
Bladder tumor staging: comparison of contrast-enhanced and gray-scale ultrasound
2009
OBJECTIVE. The purpose of this study was to evaluate the effectiveness of contrast-enhanced sonography in comparison with conventional sonography in differentiating muscle- infiltrating and superficial neoplasms of the urinary bladder. SUBJECTS AND METHODS. Conventional and contrast-enhanced sonography were performed on 34 consecutively registered patients with bladder tumors. All examinations were reviewed by two independent sonologists. At gray-scale sonography, interruption of the hyperechoic bladder wall was considered the main diagnostic criterion for differentiating superficial and infiltrating tumors. At contrast-enhanced sonography, a tumor was considered superficial when the hypoen…
Mathematical models for the diffusion magnetic resonance signal abnormality in patients with prion diseases
2014
In clinical practice signal hyperintensity in the cortex and/or in the striatum on magnetic resonance (MR) diffusion-weighted images (DWIs) is a marker of sporadic Creutzfeldt–Jakob Disease (sCJD). MR diagnostic accuracy is greater than 90%, but the biophysical mechanisms underpinning the signal abnormality are unknown. The aim of this prospective study is to combine an advanced DWI protocol with new mathematical models of the microstructural changes occurring in prion disease patients to investigate the cause of MR signal alterations. This underpins the later development of more sensitive and specific image-based biomarkers. DWI data with a wide a range of echo times and diffusion weightin…
Computational fluid dynamics in the assessment of patients' postoperative status after glottis-widening surgery
2017
Background. Computational fluid dynamics (CFD), a rapidly developing instrument with a number of practical applications, allows calculation and visualization of the changing parameters of airflow in the upper respiratory tract. Objectives. The aim of this study was to demonstrate the advantages of CFD as an instrument for noninvasive tests of the larynx in patients who had undergone surgical treatment due to bilateral vocal fold paralysis. Material and Methods. Surface measurements of the glottic space were made during maximum adduction of the vocal folds. Additionally, the following spirometric parameters were determined: forced vital capacity (FVC), forced expiratory volume in the first s…
A spline-based non-linear diffeomorphism for multimodal prostate registration.
2012
This paper presents a novel method for non-rigid registration of transrectal ultrasound and magnetic resonance prostate images based on a non-linear regularized framework of point correspondences obtained from a statistical measure of shape-contexts. The segmented prostate shapes are represented by shape-contexts and the Bhattacharyya distance between the shape representations is used to find the point correspondences between the 2D fixed and moving images. The registration method involves parametric estimation of the non-linear diffeomorphism between the multimodal images and has its basis in solving a set of non-linear equations of thin-plate splines. The solution is obtained as the least…
Compliance and Pulse Wave Velocity Assessed by MRI Detect Early Aortic Impairment in Young Patients With Mutation of the Smooth Muscle Myosin Heavy C…
2008
Purpose To evaluate aortic elasticity with MRI on young asymptomatic individuals with mutation of the smooth muscle myosin heavy chain in whom aortic enlargement is not present. Materials and Methods Aortic compliance, aortic distensibility, and pulse wave velocity (PWV) were semiautomatically measured from MRI in 8 asymptomatic subjects having a mutation of the MYH11 gene (M+) and 21 nonmutated relatives (M−) of similar age, sex, and blood pressure characteristics. Results Despite a similar aortic diameter in both groups, the aortic compliance and distensibility were significantly lower in M+ subjects compared with M− (0.84 ± 0.33 versus 2.03 ± 0.54 mm2/mmHg, 1.18 ± 0.62 10−3 versus 5.11 ±…
Evaluation of prostate segmentation algorithms for MRI: The PROMISE12 challenge
2014
Contains fulltext : 137969.pdf (Publisher’s version ) (Open Access) Prostate MRI image segmentation has been an area of intense research due to the increased use of MRI as a modality for the clinical workup of prostate cancer. Segmentation is useful for various tasks, e.g. to accurately localize prostate boundaries for radiotherapy or to initialize multi-modal registration algorithms. In the past, it has been difficult for research groups to evaluate prostate segmentation algorithms on multi-center, multi-vendor and multi-protocol data. Especially because we are dealing with MR images, image appearance, resolution and the presence of artifacts are affected by differences in scanners and/or …
Computer-aided diagnosis system for characterizing ISUP grade≥2 prostate cancers at multiparametric MRI: A cross-vendor evaluation.
2019
International audience; Purpose: To assess the performance of a computer-aided diagnosis (CADx) system trained at characterizing International Society of Urological Pathology (ISUP) grade >= 2 peripheral zone (PZ) prostate cancers on multiparametric magnetic resonance imaging (mpMRI) examinations from a different institution and acquired on different scanners than those used for the training database.Patients and methods: Preoperative mpMRIs of 74 men (median age, 65.7 years) treated by prostatectomy between 2014 and 2017 were retrospectively selected. One radiologist outlined suspicious lesions and scored them using Prostate Imaging-Reporting and Data System version 2 (PI-RADSv2); their CA…
ProstateAnalyzer: web-based medical application for the management of prostate cancer using multiparametric MR imaging
2016
Objectives: In this paper, we present ProstateAnalyzer, a new web-based medical tool for prostate cancer diagnosis. ProstateAnalyzer allows the visualization and analysis of magnetic resonance images (MRI) in a single framework. Methods: ProstateAnalyzer recovers the data from a PACS server and displays all the associated MRI images in the same framework, usually consisting of 3D T2-weighted imaging for anatomy, dynamic contrast-enhanced MRI for perfusion, diffusion-weighted imaging in the form of an apparent diffusion coefficient (ADC) map and MR Spectroscopy. ProstateAnalyzer allows annotating regions of interest in a sequence and propagates them to the others. Results: From a representat…