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1.
Eur Radiol ; 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38581609

RESUMO

Susceptibility-weighted imaging (SWI) has become a standard component of most brain MRI protocols. While traditionally used for detecting and characterising brain hemorrhages typically associated with stroke or trauma, SWI has also shown promising results in glioma assessment. Numerous studies have highlighted SWI's role in differentiating gliomas from other brain lesions, such as primary central nervous system lymphomas or metastases. Additionally, SWI aids radiologists in non-invasively grading gliomas and predicting their phenotypic profiles. Various researchers have suggested incorporating SWI as an adjunct sequence for predicting treatment response and for post-treatment monitoring. A significant focus of these studies is on the detection of intratumoural susceptibility signals (ITSSs) in gliomas, which are indicative of microhemorrhages and vessels within the tumour. The quantity, distribution, and characteristics of these ITSSs can provide radiologists with more precise information for evaluating and characterising gliomas. Furthermore, the potential benefits and added value of performing SWI after the administration of gadolinium-based contrast agents (GBCAs) have been explored. This review offers a comprehensive, educational, and practical overview of the potential applications and future directions of SWI in the context of glioma assessment. CLINICAL RELEVANCE STATEMENT: SWI has proven effective in evaluating gliomas, especially through assessing intratumoural susceptibility signal changes, and is becoming a promising, easily integrated tool in MRI protocols for both pre- and post-treatment assessments. KEY POINTS: • Susceptibility-weighted imaging is the most sensitive sequence for detecting blood and calcium inside brain lesions. • This sequence, acquired with and without gadolinium, helps with glioma diagnosis, characterisation, and grading through the detection of intratumoural susceptibility signals. • There are ongoing challenges that must be faced to clarify the role of susceptibility-weighted imaging for glioma assessment.

2.
Eur J Radiol ; 143: 109900, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34412007

RESUMO

Evaluation of Central Nervous System (CNS) focal lesions has been classically made focusing on the assessment solid or enhancing component. However, the assessment of solitary peripherally enhancing lesions where the differential diagnosis includes High-Grade Gliomas (HGG) and metastasis, is usually challenging. Several studies have tried to address the characteristics of peritumoral non-enhancing areas, for better characterization of these lesions. Peritumoral hyperintense T2/FLAIR signal abnormality predominantly contains infiltrating tumor cells in HGG whereas CNS metastasis induce pure vasogenic edema. In addition, the accurate determination of the real extension of HGG is critical for treatment selection and outcome. Conventional MRI sequences are limited in distinguishing infiltrating neoplasm from vasogenic edema. Advanced MRI sequences like Diffusion Weighted Imaging (DWI), Diffusion Tensor Imaging (DTI), Perfusion Weighted Imaging (PWI) and MR spectroscopy (MRS) have all been utilized for this aim with acceptable results. Other advanced MRI approaches, less explored for this task such as Arterial Spin Labelling (ASL), Diffusion Kurtosis Imaging (DKI), T2 relaxometry or Amide Proton Transfer (APT) are also showning promising results in this scenario. In this article, we will discuss the physiopathological basis of peritumoral T2/FLAIR signal abnormality and review potential applications of advanced MRI sequences for its evaluation.


Assuntos
Neoplasias Encefálicas , Glioma , Encéfalo , Neoplasias Encefálicas/diagnóstico por imagem , Diagnóstico Diferencial , Imagem de Difusão por Ressonância Magnética , Imagem de Tensor de Difusão , Glioma/diagnóstico , Humanos , Imageamento por Ressonância Magnética
3.
J Neuroimaging ; 31(3): 428-445, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33856735

RESUMO

Vascular malformations (VMs) of the central nervous system (CNS) include a wide range of pathological conditions related to intra and extracranial vessel abnormalities. Although some VMs show typical neuroimaging features, other VMs share and overlap pathological and neuroimaging features that hinder an accurate differentiation between them. Hence, it is not uncommon to misclassify different types of VMs under the general heading of arteriovenous malformations. Thorough knowledge of the imaging findings of each type of VM is mandatory to avoid these inaccuracies. Conventional MRI sequences, including MR angiography, have allowed the evaluation of CNS VMs without using ionizing radiation. Newer MRI techniques, such as susceptibility-weighted imaging, black blood sequences, arterial spin labeling, and 4D flow imaging, have an added value of providing physiopathological data in real time regarding the hemodynamics of VMs. Beyond MR images, new insights using 3D printed models are being incorporated as part of the armamentarium for a noninvasive evaluation of VMs. In this paper, we briefly review the pathophysiology of CNS VMs, focusing on the MRI findings that may be helpful to differentiate them. We discuss the role of each conventional and advanced MRI sequence for VMs assessment and provide some insights about the value of structured reports of 3D printing to evaluate VMs.


Assuntos
Malformações Vasculares do Sistema Nervoso Central/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Neuroimagem/métodos , Adulto , Sistema Nervoso Central/irrigação sanguínea , Hemodinâmica/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Marcadores de Spin
6.
Ann Maxillofac Surg ; 10(1): 267-271, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32855956

RESUMO

The aim of this study is to describe the clinical, radiological and histological characteristics that define lipoblastomas with special emphasis on differential diagnosis. The patient is a 5-year-old girl who consulted for a rapidly growing lower cheek tumor. This study analyzes, evaluates, and discusses the issues that need to be addressed throughout the process that affect treatment planning and provides an updated review of these rare head-and-neck tumors.

7.
Eur Radiol Exp ; 3(1): 23, 2019 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-31197486

RESUMO

BACKGROUND: To evaluate changes in perfusion computed tomography (PCT) parameters induced by treatment with conventional chemotherapy (CCT) alone or with CCT and radiation therapy (RT) in patients with non-small cell lung cancer (NSCLC) and to determine whether these changes correlate with response as defined by the response evaluation criteria in solid tumours version 1.1 (RECIST-1.1). METHODS: Fifty-three patients with a histological diagnosis of NSCLC prospectively underwent PCT of the whole tumour, before/after CCT or before/after CCT and RT. Blood flow (BF), blood volume (BV), permeability (PMB), and mean transit time (MTT) were compared before and after treatment and with the response as defined by RECIST-1.1. The relationship between changes in the perfusion parameters and in tumour size was also evaluated. RESULTS: PCT parameters decreased after treatment, significantly for BV (p = 0.002) and MTT (p = 0.027). The 30 patients with partial response had a significant decrease of 21% for BV (p = 0.006) and 17% for MTT (p = 0.031). A non-significant decrease in all perfusion parameters was found in patients with stable disease (p > 0.137). In patients with progressive disease, MTT decreased by 10% (p = 0.465) and the other parameters did not significantly vary (p > 0.809). No significant correlation was found between changes in size and PCT parameters (p > 0.145). CONCLUSIONS: Treatment of NSCLC with platinum derivatives, with or without RT, induces changes in PCT parameters. Partial response is associated with a significant decrease in BV and MTT, attributable to the effect of the treatment on tumour vascularisation.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Carcinoma Pulmonar de Células não Pequenas/terapia , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/terapia , Critérios de Avaliação de Resposta em Tumores Sólidos , Tomografia Computadorizada por Raios X , Adulto , Idoso , Carcinoma Pulmonar de Células não Pequenas/irrigação sanguínea , Quimiorradioterapia , Feminino , Humanos , Neoplasias Pulmonares/irrigação sanguínea , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fluxo Sanguíneo Regional , Tomografia Computadorizada por Raios X/métodos , Resultado do Tratamento
8.
Eur Radiol ; 26(9): 3199-207, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26699372

RESUMO

OBJECTIVES: To determine whether the quantification of iodine with stress dual-energy computed tomography (DECT-S) allows for the discrimination between a normal and an ischemic or necrotic myocardium using magnetic resonance (MR) as a reference. METHODS: This retrospective study was approved by the institutional review board, with waiver of informed consent. Thirty-six cardiac MR and DECT-S images from patients with suspected coronary artery disease were evaluated. Perfusion defects were visually determined, and myocardial iodine concentration was calculated by two observers using DECT colour-coded iodine maps. Iodine concentration differences were calculated using parametric tests. Receiver operating characteristic (ROC) curve analysis was conducted to estimate the optimal iodine concentration threshold for discriminating pathologic myocardium. RESULTS: In total, 576 cardiac segments were evaluated. There were differences in mean iodine concentration (p < 0.001) between normal (2.56 ± 0.66 mg/mL), ischemic (1.98 ± 0.36 mg/dL) and infarcted segments (1.35 ± 0.57 mg/mL). A myocardium iodine concentration of 2.1 mg/mL represented the optimal threshold to discriminate between normal and pathologic myocardium (sensitivity 75 %, specificity 73.6 %, area under the curve 0.806). Excellent agreement was found in measured myocardium iodine concentration (intraclass correlation coefficient 0.814). CONCLUSION: Cardiac DECT-S with iodine quantification may be useful to differentiate healthy and ischemic or necrotic myocardium. KEY POINTS: • DECT-S allows for determination of myocardial iodine concentration as a quantitative perfusion parameter. • A high interobserver correlation exists in measuring myocardial iodine concentration with DECT-S. • Myocardial iodine concentration may be useful in the assessment of patients with CAD.


Assuntos
Iodo/farmacocinética , Infarto do Miocárdio/diagnóstico , Miocárdio/metabolismo , Tomografia Computadorizada por Raios X/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/metabolismo , Curva ROC , Estudos Retrospectivos
9.
Skeletal Radiol ; 44(4): 477-90, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25367671

RESUMO

Soft-tissue lesions of the fingers are commonly found in daily clinical practice. A wide range of tumors and pseudotumors have been described in this location, and the majority of them are benign. Ganglion cysts are the most common entity, and the localized type of tenosynovial giant cell tumors are the most frequent solid condition. Both may be easily recognized owing to their typical clinical and radiological characteristics. However, categorization of the spectrum of soft-tissue lesions of the fingers remains limited, despite imaging development, and many patients undergo surgery before radiological or histological diagnosis. Clinical history, radiographic features, and ultrasound and magnetic resonance patterns may help in obtaining the correct diagnosis or reducing the list of differential diagnoses. Radiologists should be familiar with imaging findings so that they can determine the size, extension, and affected neighboring anatomical structures, and provide information that allows adequate presurgical counseling.


Assuntos
Diagnóstico por Imagem/métodos , Dedos , Neoplasias de Tecidos Moles/diagnóstico , Diagnóstico Diferencial , Cistos Glanglionares/diagnóstico por imagem , Cistos Glanglionares/patologia , Hemangioma/diagnóstico por imagem , Hemangioma/patologia , Humanos , Imageamento por Ressonância Magnética , Radiografia , Ultrassonografia
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