0000000000174554
AUTHOR
Alex Rovira
Power estimation for non-standardized multisite studies
A concern for researchers planning multisite studies is that scanner and T1-weighted sequence-related biases on regional volumes could overshadow true effects, especially for studies with a heterogeneous set of scanners and sequences. Current approaches attempt to harmonize data by standardizing hardware, pulse sequences, and protocols, or by calibrating across sites using phantom-based corrections to ensure the same raw image intensities. We propose to avoid harmonization and phantom-based correction entirely. We hypothesized that the bias of estimated regional volumes is scaled between sites due to the contrast and gradient distortion differences between scanners and sequences. Given this…
Abstract 4258: Preliminarily results of the Oncohabitats Study: A multicentre validation of overall survival (OS) estimation of patients with glioblastoma (GBM) using vascular biomarkers
Abstract We report preliminarily results of an international retrospective study (NCT03439332) analyzing the prognostic value of the early assessment of vascular architecture of glioblastoma (GBM). The initial cohort included 300 pts treated at 7 European hospitals. Multiparametric images were processed by Oncohabitats (www.oncohabitats.upv.es) to obtain the cerebral blood volume (CBV) and cerebral blood flow (CBF) from 4 automatically delimited regions of interest (ROIs): high angiogenic tumor (HAT), low angiogenic tumor (LAT), infiltrating peripherial edema (IPE), and vasogenic peripherial edema (VPE). Uniparametric Cox regression models and Kaplan-Meier analysis were developed to test pr…
Texture analysis in susceptibility-weighted imaging may be useful to differentiate acute from chronic multiple sclerosis lesions.
To evaluate the diagnostic performance of texture analysis (TA) applied on non-contrast-enhanced susceptibility-weighted imaging (SWI) to differentiate acute (enhancing) from chronic (non-enhancing) multiple sclerosis (MS) lesions. We analyzed 175 lesions from 58 patients with relapsing-remitting MS imaged on a 3.0 T MRI scanner and applied TA on T2-w and SWI images to extract texture features. We evaluated the presence or absence of lesion enhancement on T1-w post-contrast images and performed a computational statistical analysis to assess if there was any significant correlation between the texture features and the presence of lesion activity. ROC curves and leave-one-out cross-validation…
Diagnosis of multiple sclerosis: a multicentre study to compare revised McDonald-2010 and Filippi-2010 criteria
MRI has been formally included in the diagnostic work-up of patients with a suspicion of multiple sclerosis (MS) in 2001, to demonstrate disease dissemination in space (DIS) and time (DIT) and to exclude alternative diagnoses.1 Over time, these criteria have been modified to simplify their use and to clarify specific aspects (eg, spinal cord findings).2 One aspect marginally analysed in the diagnostic work-up of patients with clinically isolated syndrome (CIS) is the role of intracortical lesions (ICLs), which are a prominent feature of MS and contribute to disability and cognitive impairment.2 A single-centre study3 showed that inclusion of ICL for the evaluation of DIS in CIS increased th…
Robust association between vascular habitats and patient prognosis in glioblastoma: An international multicenter study
Background Glioblastoma (GBM) is the most aggressive primary brain tumor, characterized by a heterogeneous and abnormal vascularity. Subtypes of vascular habitats within the tumor and edema can be distinguished: high angiogenic tumor (HAT), low angiogenic tumor (LAT), infiltrated peripheral edema (IPE), and vasogenic peripheral edema (VPE). Purpose To validate the association between hemodynamic markers from vascular habitats and overall survival (OS) in glioblastoma patients, considering the intercenter variability of acquisition protocols. Study Type Multicenter retrospective study. Population In all, 184 glioblastoma patients from seven European centers participating in the NCT03439332 c…