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    Renal angiomyolipomas: Typical and atypical features on computed tomography and magnetic resonance imaging
    (Baishideng Publishing Group Inc., 2025-02-28)
    LABRA WEITZLER, ANDRES ANTONIO  
    ;
    SCHIAPPACASSE FAUNDES, GIANCARLO  
    ;
    Diego Constenla
    ;
    Joaquin Cristi
    <jats:p>Angiomyolipomas (AMLs) represent the most common benign solid renal tumors. The frequency of their detection in the general population is increasing owing to advances in imaging technology. The objective of this review is to discuss computed tomography (CT) and magnetic resonance imaging findings for both typical and atypical renal AMLs, along with their associated complications. AMLs are typically defined as solid triphasic tumors composed of varying amounts of dysmorphic and tortuous blood vessels, smooth muscle components and adipose tissue. In an adult, a classical renal AML appears as a solid, heterogeneous renal cortical mass with macroscopic fat. However, up to 5% of AMLs contain minimal fat and cannot be reliably diagnosed by imaging. Fat-poor AMLs can appear as hyperattenuating masses on unenhanced CT and as hypointense masses on T2WI; other AMLs may be isodense or exhibit cystic components. Hemorrhage is the most common complication, and AMLs with hemorrhage can mimic other tumors, making their diagnosis challenging. Understanding the variable and heterogeneous nature of this neoplasm to correctly classify renal AMLs and to avoid misdiagnosis of other renal lesions is crucial.</jats:p>
      4
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    Impact of myocardial scar burden on microvascular resistance reserve in patients with coronary artery disease
    (Springer Science and Business Media LLC, 2025-02-20)
    Masahiro Hoshino
    ;
    Roel Hoek
    ;
    Ruurt. A. Jukema
    ;
    Jorge Dahdal
    ;
    Pepijn van Diemen
    Purpose The impact of myocardial scar on coronary microcirculation is not well understood. This study aims to evaluate the association between microvascular resistance reserve (MRR) and scar tissue. Methods In this post-hoc analysis of the PACIFIC 2 trial, symptomatic patients with prior myocardial infarction (MI) and/or percutaneous coronary intervention (PCI) underwent [15O]H2O positron emission tomography (PET), cardiac magnetic resonance (CMR) imaging, and fractional flow reserve (FFR). MRR was assessed utilizing PET-derived coronary flow reserve and FFR measurements. Scar quantification was assessed by CMR late gadolinium enhancement (LGE). Vessel LGE burden was defined as the scar tissue proportion in each myocardial territory. Total LGE burden was defined as the proportion of overall scar. Results The study included 154 patients with 397 vessels with a mean MRR of 3.56 ± 1.24. Patients with any scar tissues (LGE > 0%) exhibited a lower MRR in every myocardial territory than those without scar tissues. After adjusting for cardiovascular risk factors, either vessel LGE burden (β =-0.013, P = 0.006) or total LGE burden (β =-0.039, P = 0.002) independently predicted a reduced MRR. Compared to myocardial territories without scar tissues (LGE burdens = 0%), MRR was significantly lower in myocardial territories with vessel LGE burden = 0% + total LGE burden > 0%, and in myocardial territories with both LGE burdens > 0%. Conclusion Scar burden was negatively associated with MRR in patients with prior MI and/or PCI. Our findings indicate that both the proportion of myocardial scar in the vascular territory and the overall myocardial scar affect the microcirculation of individual vascular territories.
      1Scopus© Citations 4
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    White matter volume and microstructural integrity are associated with fatigue in relapsing multiple sclerosis
    (Springer Science and Business Media LLC, 2025-05-12)
    FIGUEROA VARGAS, ALEJANDRA MABEL  
    ;
    Sebastián Navarrete-Caro
    ;
    Claudia Cárcamo
    ;
    Ethel Ciampi
    ;
    Macarena Vásquez-Torres
      10
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    Scopus© Citations 3  8
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    Secondary rectal linitis plastica caused by prostatic adenocarcinoma - magnetic resonance imaging findings and dissemination pathways: A case report
    (2024)
    LABRA WEITZLER, ANDRES ANTONIO  
    ;
    SCHIAPPACASSE FAUNDES, GIANCARLO  
    ;
    Rolando Alfonso Cocio
    ;
    Jorge Tomás Torres
    ;
    GONZALEZ COFRE, FERNANDO OMAR  
    <jats:p>BACKGROUND</jats:p> <jats:p>Secondary rectal linitis plastica (RLP) from prostatic adenocarcinoma is a rare and poorly understood form of metastatic spread, characterized by a desmoplastic response and concentric rectal wall infiltration with mucosal preservation. This complicates endoscopic diagnosis and can mimic gastrointestinal malignancies. This case series underscores the critical role of magnetic resonance imaging (MRI) in identifying the distinct imaging features of RLP and highlights the importance of considering this condition in the differential diagnosis of patients with a history of prostate cancer.</jats:p> <jats:p>CASE SUMMARY</jats:p> <jats:p>Three patients with secondary RLP due to prostatic adenocarcinoma presented with varied clinical features. The first patient, a 76-year-old man with advanced prostate cancer, had rectal pain and incontinence. MRI showed diffuse prostatic invasion and significant rectal wall thickening with a characteristic "target sign" pattern. The second, a 57-year-old asymptomatic man with elevated prostate-specific antigen levels and a history of prostate cancer exhibited rectoprostatic angle involvement and rectal wall thickening on MRI, with positron emission tomography/computed tomography PSMA confirming the prostatic origin of the metastatic spread. The third patient, an 80-year-old post-radical prostatectomy, presented with refractory constipation. MRI revealed a neoplastic mass infiltrating the rectal wall. In all cases, MRI consistently showed stratified thickening, concentric signal changes, restricted diffusion, and contrast enhancement, which were essential for diagnosing secondary RLP. Biopsies confirmed the prostatic origin of the neoplastic involvement in the rectum.</jats:p> <jats:p>CONCLUSION</jats:p> <jats:p>Recognizing MRI findings of secondary RLP is essential for accurate diagnosis and management in prostate cancer patients.</jats:p>
      1
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    Approaches to supratentorial brain tumours in children
    (2024)
    Francisco Sepulveda
    ;
    Raffaella Scotto Opipari
    ;
    Fiorenza Coppola
    ;
    Antonia Ramaglia
    ;
    Kshitij Mankad
    Scopus© Citations 1  5
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    The BrainLat project, a multimodal neuroimaging dataset of neurodegeneration from underrepresented backgrounds
    (2023)
    Pavel Prado
    ;
    Vicente Medel
    ;
    Raul Gonzalez-Gomez
    ;
    Agustín Sainz-Ballesteros
    ;
    Victor Vidal
    The Latin American Brain Health Institute (BrainLat) has released a unique multimodal neuroimaging dataset of 780 participants from Latin American. The dataset includes 530 patients with neurodegenerative diseases such as Alzheimer’s disease (AD), behavioral variant frontotemporal dementia (bvFTD), multiple sclerosis (MS), Parkinson’s disease (PD), and 250 healthy controls (HCs). This dataset (62.7 ± 9.5 years, age range 21–89 years) was collected through a multicentric effort across five Latin American countries to address the need for affordable, scalable, and available biomarkers in regions with larger inequities. The BrainLat is the first regional collection of clinical and cognitive assessments, anatomical magnetic resonance imaging (MRI), resting-state functional MRI (fMRI), diffusion-weighted MRI (DWI), and high density resting-state electroencephalography (EEG) in dementia patients. In addition, it includes demographic information about harmonized recruitment and assessment protocols. The dataset is publicly available to encourage further research and development of tools and health applications for neurodegeneration based on multimodal neuroimaging, promoting the assessment of regional variability and inclusion of underrepresented participants in research.
      30Scopus© Citations 22
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      5
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      9Scopus© Citations 7
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    Multivariate word properties in fluency tasks reveal markers of Alzheimer's dementia
    (2023)
    Franco J. Ferrante
    ;
    Joaquín Migeot
    ;
    Agustina Birba
    ;
    Lucía Amoruso
    ;
    Gonzalo Pérez
    <jats:title>Abstract</jats:title><jats:sec><jats:title>INTRODUCTION</jats:title><jats:p>Verbal fluency tasks are common in Alzheimer's disease (AD) assessments. Yet, standard valid response counts fail to reveal disease‐specific semantic memory patterns. Here, we leveraged automated word‐property analysis to capture neurocognitive markers of AD vis‐à‐vis behavioral variant frontotemporal dementia (bvFTD).</jats:p></jats:sec><jats:sec><jats:title>METHODS</jats:title><jats:p>Patients and healthy controls completed two fluency tasks. We counted valid responses and computed each word's frequency, granularity, neighborhood, length, familiarity, and imageability. These features were used for group‐level discrimination, patient‐level identification, and correlations with executive and neural (magnetic resonanance imaging [MRI], functional MRI [fMRI], electroencephalography [EEG]) patterns.</jats:p></jats:sec><jats:sec><jats:title>RESULTS</jats:title><jats:p>Valid responses revealed deficits in both disorders. Conversely, frequency, granularity, and neighborhood yielded robust group‐ and subject‐level discrimination only in AD, also predicting executive outcomes. Disease‐specific cortical thickness patterns were predicted by frequency in both disorders. Default‐mode and salience network hypoconnectivity, and EEG beta hypoconnectivity, were predicted by frequency and granularity only in AD.</jats:p></jats:sec><jats:sec><jats:title>DISCUSSION</jats:title><jats:p>Word‐property analysis of fluency can boost AD characterization and diagnosis.</jats:p></jats:sec><jats:sec><jats:title>Highlights</jats:title><jats:p><jats:list list-type="bullet"> <jats:list-item><jats:p>We report novel word‐property analyses of verbal fluency in AD and bvFTD.</jats:p></jats:list-item> <jats:list-item><jats:p>Standard valid response counts captured deficits and brain patterns in both groups.</jats:p></jats:list-item> <jats:list-item><jats:p>Specific word properties (e.g., frequency, granularity) were altered only in AD.</jats:p></jats:list-item> <jats:list-item><jats:p>Such properties predicted cognitive and neural (MRI, fMRI, EEG) patterns in AD.</jats:p></jats:list-item> <jats:list-item><jats:p>Word‐property analysis of fluency can boost AD characterization and diagnosis.</jats:p></jats:list-item> </jats:list></jats:p></jats:sec>
      3Scopus© Citations 10