Publications by authors named "Alcaide-Leon P"

MRI is the preferred method for follow-up imaging of post-treatment WHO grade 3 or 4 gliomas. While positron emission tomography with O-(2-[F]fluoroethyl)-L-tyrosine) (F-FET PET) offers higher diagnostic accuracy, its use is limited due to low availability. We propose a sequential, threshold-based workflow to triage patients for additional F-FET PET scans based on MRI dynamic susceptibility contrast (DSC) perfusion-derived rCBV values, to optimize F-FET PET resource allocation.

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Background And Purpose: Gadolinium-based contrast agents are widely used for meningioma imaging; however, concerns exist regarding their side effects, cost, and environmental impact. At the standard gadolinium dose, most meningiomas show avid contrast enhancement, suggesting that administering a smaller dose may be feasible. The purpose of this study was to evaluate the impact of a lower gadolinium dose on the differentiation between meningiomas and adjacent intracranial tissues.

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Introduction: The purpose of this retrospective study was to compare two, widely available software packages for calculation of Dynamic Susceptibility Contrast (DSC) perfusion MRI normalized relative Cerebral Blood Volume (rCBV) values to differentiate tumor progression from pseudoprogression in treated high-grade glioma patients.

Material And Methods: rCBV maps processed by Siemens Syngo.via (Siemens Healthineers) and Olea Sphere (Olea Medical) software packages were co-registered to contrast-enhanced T1 (T1-CE).

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Objective: Previous studies using advanced magnetic resonance imaging (MRI) techniques have documented abnormal transmantle bands connecting ectopic nodules to overlying cortex in patients with periventricular nodular heterotopia (PNH). We describe a similar finding using conventional MRI techniques.

Methods: Patients were identified by means of a full-text search of radiological reports.

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Background: Sexual dysfunction (SD) is frequently reported in multiple sclerosis (MS) and is likely related to MS-related damage to the spinal cord (SC).

Objective: To assess associations between SD and quantitative MRI measures in people with MS (pwMS).

Methods: This pilot study included 17 pwMS with SD who completed questionnaires assessing SD, mood, and fatigue.

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Background And Objectives: To report a novel tauopathy in a patient with protracted course progressive supranuclear palsy (PC-PSP).

Methods: This was a clinical follow-up, gene analysis, neuropathologic study.

Results: A 73-year-old man presented with diplopia, slowness, shuffling gait, and falls.

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To quantitatively compare the recurrence patterns of glioblastoma (isocitrate dehydrogenase-wild type) versus grade 4 isocitrate dehydrogenase-mutant astrocytoma (wild type isocitrate dehydrogenase and mutant isocitrate dehydrogenase, respectively) following primary chemoradiation. A retrospective matched cohort of 22 wild type isocitrate dehydrogenase and 22 mutant isocitrate dehydrogenase patients were matched by sex, extent of resection, and corpus callosum involvement. The recurrent gross tumor volume was compared to the original gross tumor volume and clinical target volume contours from radiotherapy planning.

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Article Synopsis
  • The MDS Video Challenge is a popular session at the International Congress, emphasizing complex case presentations through videos.
  • Past cases have highlighted unique neuroimaging findings, leading to the creation of two anthologies: one on genetic conditions and another on acquired conditions.
  • Each case includes clinical details, neuroimaging findings, characteristic features of the disorder, and differential diagnoses for clarity.
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We selected several "imaging pearls" presented during the Movement Disorder Society (MDS) Video Challenge for this review. While the event, as implicated by its name, was video-centered, we would like to emphasize the important role of imaging in making the correct diagnosis. We divided this anthology into two parts: genetic and acquired disorders.

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Purpose: To investigate gender differences in diagnostic radiology practice, specifically, the differences in scope of practice, the frequency of consultations to other colleagues, and the error rates.

Material And Methods: A retrospective observational study was performed including radiologists working for a European teleradiology provider between 2013 and 2019. Main outcome measures included the adjusted odds ratio of female gender for reporting cases in more than one subspecialty, the adjusted incidence rate ratio (IRR) of female gender for the count of second opinion requests to other colleagues, and the adjusted IRR of female gender for the count of radiologic errors.

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Purpose: Differentiation of radiation necrosis from tumor progression in brain metastases treated with stereotactic radiosurgery (SRS) is challenging. For this, we assessed the performance of the centrally restricted diffusion sign.

Methods: Patients with brain metastases treated with SRS who underwent a subsequent intervention (biopsy/resection) for a ring-enhancing lesion on preoperative MRI between 2000 and 2020 were included.

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Background: Diagnostic classification of diffuse gliomas now requires an assessment of molecular features, often including IDH-mutation and 1p19q-codeletion status. Because genetic testing requires an invasive process, an alternative noninvasive approach is attractive, particularly if resection is not recommended. The goal of this study was to evaluate the effects of training strategy and incorporation of biologically relevant images on predicting genetic subtypes with deep learning.

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Onboard, real-time, imaging techniques, from the original megavoltage planar imaging devices, to the emerging combined MRI-Linear Accelerators, have brought a huge transformation in the ability to deliver targeted radiation therapies. Each generation of these technologies enables lethal doses of radiation to be delivered to target volumes with progressively more accuracy and thus allows shrinking of necessary geometric margins, leading to reduced toxicities. Alongside these improvements in treatment delivery, advances in medical imaging, e.

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Background And Purpose: Differentiating between treatment-related lesions and tumor progression remains one of the greatest dilemmas in neuro-oncology. Diffusion MR imaging characteristics may provide useful information to help make this distinction. The aim of the study was to assess the diagnostic accuracy of the centrally reduced diffusion sign for differentiation of treatment-related lesions and true tumor progression in patients with suspected glioma recurrence.

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Although combined spin- and gradient-echo (SAGE) dynamic susceptibility-contrast (DSC) MRI can provide perfusion quantification that is sensitive to both macrovessels and microvessels while correcting for T -shortening effects, spatial coverage is often limited in order to maintain a high temporal resolution for DSC quantification. In this work, we combined a SAGE echo-planar imaging (EPI) sequence with simultaneous multi-slice (SMS) excitation and blipped controlled aliasing in parallel imaging (blipped CAIPI) at 3 T to achieve both high temporal resolution and whole brain coverage. Two protocols using this sequence with multi-band (MB) acceleration factors of 2 and 3 were evaluated in 20 patients with treated gliomas to determine the optimal scan parameters for clinical use.

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Background: Differentiating treatment-induced injury from recurrent high-grade glioma is an ongoing challenge in neuro-oncology, in part due to lesion heterogeneity. This study aimed to determine whether different MR features were relevant for distinguishing recurrent tumor from the effects of treatment in contrast-enhancing lesions (CEL) and non-enhancing lesions (NEL).

Methods: This prospective study analyzed 291 tissue samples (222 recurrent tumor, 69 treatment-effect) with known coordinates on imaging from 139 patients who underwent preoperative 3T MRI and surgery for a suspected recurrence.

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Objectives: Treatment-induced lesions represent a great challenge in neuro-oncology. The aims of this study were (i) to characterize treatment induced lesions in glioblastoma patients treated with chemoradiotherapy and heat-shock protein (HSP) vaccine and (ii) to evaluate the diagnostic accuracy of diffusion weighted imaging for differentiation between treatment-induced lesions and tumor progression.

Methods: Twenty-seven patients with newly diagnosed glioblastoma treated with HSP vaccine and chemoradiotherapy were included.

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Background: We investigated prognostic models based on clinical, radiologic, and radiomic feature to preoperatively identify meningiomas at risk for poor outcomes.

Methods: Retrospective review was performed for 303 patients who underwent resection of 314 meningiomas (57% World Health Organization grade I, 35% grade II, and 8% grade III) at two independent institutions, which comprised primary and external datasets. For each patient in the primary dataset, 16 radiologic and 172 radiomic features were extracted from preoperative magnetic resonance images, and prognostic features for grade, local failure (LF) or overall survival (OS) were identified using the Kaplan-Meier method, log-rank tests and recursive partitioning analysis.

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Background And Purpose: Spinal cord atrophy (SCA) is an important emerging outcome measure in multiple sclerosis (MS); however, there is limited consensus on the magnitude and rate of atrophy. The objective of this study was to synthesize the available data on measures of SCA in MS.

Methods: Using published guidelines, relevant literature databases were searched between 1977 and 2017 for case-control or cohort studies reporting a quantitative measure of SCA in MS patients.

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Purpose To validate ferumoxytol-based quantitative blood oxygenation level-dependent (BOLD) MRI for mapping oxygenation of human infiltrative astrocytomas by using intraoperative measurement of tissue oxygen tension and histologic staining. Materials and Methods Fifteen patients with infiltrative astrocytomas were recruited into this prospective multicenter study between July 2014 and December 2016. Prior to treatment, participants underwent preoperative quantitative BOLD MRI with ferumoxytol to generate tissue oxygen saturation (StO) maps.

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Objectives: To assess whether quantitative spinal cord MRI (SC-MRI) measures, including atrophy, and diffusion tensor imaging (DTI) and magnetization transfer imaging metrics were different in radiologically isolated syndrome (RIS) vs healthy controls (HCs).

Methods: Twenty-four participants with RIS and 14 HCs underwent cervical SC-MRI on a 3T magnet. Manually segmented regions of interest circumscribing the spinal cord cross-sectional area (SC-CSA) between C3 and C4 were used to extract SC-CSA, fractional anisotropy, mean, perpendicular, and parallel diffusivity (MD, λ, and λ) and magnetization transfer ratio (MTR).

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Purpose: Multinodular and vacuolating neuronal tumor (MVNT) have been recently added to the WHO classification of CNS tumors and has not been extensively reported upon in the radiological literature. We report the first radiological and the largest series of cases, aiming to highlight the natural history of lesions with the imaging appearance of MVNT with long follow-up time.

Methods: In this retrospective study, we collected cases with the imaging appearance of MVNT.

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