Publications by authors named "Ramon Barajas"
Article Synopsis
- This study introduces a new way to classify patients with a type of brain cancer called IDH-wildtype glioblastomas by looking at how much of the tumor is removed during surgery.
- It involves 622 patients from one hospital and another 536 patients from three different hospitals, all of whom received standard cancer treatments and had tests to check their tumor characteristics.
- The new classification model shows that younger patients with certain tumor features have a better chance of living longer after surgery, compared to older patients or those with less successful surgeries.
Article Synopsis
- * Imaging genomics explores how genetic and molecular features relate to imaging data, potentially transforming brain tumor diagnosis and treatment.
- * The article reviews imaging genomics methods, recommends analytic techniques, discusses their clinical relevance, and proposes future research directions in tumor habitat analysis.
Article Synopsis
- The study compares the effectiveness of two contrast agents, Gadolinium (GBCA) and Ferumoxytol (FBCA), in enhancing MRI images for high-grade glioma at different field strengths (3T and 7T).
- It involved 10 patients, where lesions received both GBCA on the first day and varying doses of FBCA on the second day; CNR and nCBV were analyzed for different types of lesions.
- Results showed GBCA provided higher contrast-to-noise ratio (CNR) than FBCA at 7T, but both agents had similar performances at 3T, particularly with the higher dosage of FBCA being most effective for imaging.
Article Synopsis
- MRI is commonly used in high-grade glioma treatments to map tumor boundaries and assist in surgery, revealing important tumor biology through its measurements.
- The study found that specific MRI techniques (like T1+C) not only visualize the tumor's blood flow disruption but also indicate immune cell infiltration, enhancing our understanding of how these factors interact within the tumor environment.
- The research offers a new, unbiased methodology for linking MRI results with tumor biology, laying the groundwork for future advancements in noninvasive diagnostics and treatment strategies for patients with high-grade gliomas.
Article Synopsis
- MRI with gadolinium (Gd) is commonly used to monitor glioblastoma treatment but lacks specificity in revealing the tumor's immune environment; ferumoxytol (Fe), an iron nanoparticle, targets macrophages and microglia within glioblastomas.
- In a study involving stereotactic biopsy samples and RNA microarray analysis, researchers examined how different MRI contrast agents (Gd versus Fe) correlated with immune pathways and gene expression patterns in glioblastoma patients.
- Findings indicated that Fe-enhanced imaging provided a better understanding of immune processes, showing higher levels of immune-related gene sets and M2 polarized macrophages, highlighting its potential to inform treatment and tumor biology more effectively than standard Gd-based imaging.
Article Synopsis
- Poor clinical outcomes in glioblastoma patients may result from issues within the tumor's immune environment; understanding this could lead to better patient assessment through imaging techniques.
- The study involved patients with newly diagnosed glioblastoma who underwent MRI and tissue sampling to analyze gene expression and identify different immune signatures associated with specific MRI features.
- Results showed that different MRI phenotypes correlate with varying immune responses, with enhancing lesions reflecting a stronger immune signature compared to non-enhancing areas, indicating that MRI can be a valuable tool for assessing glioblastoma's immune microenvironment.
Article Synopsis
- Pulsed field ablation (PFA) is a heart treatment showing promise for safety, but concerns exist about its potential to create harmful gas microbubbles that may lead to brain emboli.
- In an experiment using swine models, researchers monitored the effects of PFA in the left ventricle, finding that PFA didn’t produce any microbubbles or associated cerebral abnormalities, while control swine injected with air microbubbles did show signs of brain emboli.
- The study concluded that PFA, when applied to both healthy and heart-injured tissues, doesn’t appear to cause brain emboli, suggesting it may be a safer option for cardiac procedures.
Article Synopsis
- Pathogenic mutations in key genes linked to Lynch syndrome impair DNA mismatch repair and increase cancer risk, including endometrial and colorectal cancers.
- A case study highlights an adult female with no previous cancer history who developed a multicentric glioma in different brain regions, showing distinct tumor characteristics but sharing a common genetic mutation associated with Lynch syndrome.
- The findings underscore the relevance of genetic profiling in gliomas, demonstrating that mismatched repair gene alterations may play a crucial role in the development of these brain tumors.
Article Synopsis
- Conventional MRI is useful for assessing multiple sclerosis (MS), but it has limitations in detecting early neurodegeneration and mainly shows late-stage brain atrophy.
- There is a pressing need for biomarkers that can identify neurodegenerative processes before they become irreversible, particularly with the role of oxidative stress in MS pathogenesis being underexplored.
- Recent advancements in imaging markers related to inflammation and neuronal integrity highlight the potential for non-invasive imaging to assess oxidative stress in real-time, which could enhance the understanding and management of MS and other neurodegenerative diseases.
Article Synopsis
- CE-MRI is the preferred imaging method for diagnosing and monitoring primary central nervous system lymphoma, but it may not accurately reflect the true tumor size due to its reliance on specific anatomical measurements.
- While standard T1 and T2 MRI techniques are commonly used, incorporating additional methods like diffusion-weighted and perfusion-weighted imaging could enhance understanding of tumor behavior and response to treatment.
- There is a pressing need for standardizing imaging practices and reporting, as current inconsistencies hinder effective treatment planning and clinical trial outcomes for patients with PCNSL.
Article Synopsis
- Response assessment after immunotherapy for glioblastoma is difficult due to the occurrence of pseudoprogression, which can complicate diagnosis.
- Current imaging methods like gadolinium-enhanced MRI are limited in their ability to accurately characterize this condition.
- A study using FMISO PET showed potential for measuring hypoxia in tumors, indicating that it could help differentiate between pseudoprogression and actual tumor recurrence more effectively.
Article Synopsis
- High-grade glioma (HGG) patients often have similar MRI results for disease progression and treatment-related changes, complicating treatment response evaluations.* -
- The review analyzed 28 studies, involving 638 patients with true progression and 430 with treatment-related changes, to assess the effectiveness of dynamic susceptibility contrast (DSC) MRI.* -
- Results showed DSC MRI had a combined area under the receiver operating curve (AUROC) of 0.85, with sensitivity and specificity rates of 0.84 and 0.78, respectively, indicating it is effective in distinguishing between true tumor progression and treatment-related changes.*
Article Synopsis
- PET imaging is now a key diagnostic tool in precise medicine, with various pre-targeting methods developed to improve traditional immuno-PET's limitations.
- The new Dual-Receptor Pre-Targeting (DRPT) system enhances tumor radioligand uptake and retention by using a tumor-receptor-specific peptide, outperforming previous methods.
- DRPT is compatible with short-lived isotopes, could reduce the necessary amount of pre-administered antibodies, and offers a potential cost-saving approach in antibody-based molecular imaging.
Article Synopsis
- The article discusses the challenges faced in imaging brain tumors due to the rise of immune-modulating therapies and the need for personalized treatment plans.
- It highlights the limitations of existing imaging techniques like gadolinium contrast-enhanced MRI and FDG PET, and emphasizes the importance of understanding the tumor's interaction with the immune system.
- The article aims to provide insights on imaging methods for detecting neuroinflammation in brain tumors and offers practical guidance on using iron nanoparticle imaging as a tool for diagnosing and monitoring these malignancies.
Article Synopsis
- A case study of a 6-year-old girl presented severe symptoms from a high-grade AVM, leading to surgery and initial SRS treatment, but she later developed recurrent symptoms due to a new AVM nidus.
- The treatment for her persistent RIN shifted from steroids to bevacizumab, resulting in a significant improvement in her symptoms and reduced side effects associated with long-term steroid use.
Article Synopsis
- Amino acid PET imaging is valuable for assessing brain tumors but is rarely used in clinical settings due to high costs.
- This study involved 17 patients undergoing PET/MRI scans grouped by the day of tracer production, leading to cost savings and improved access.
- The results showed a 48.5% reduction in costs when patients were scanned in batches, highlighting how strategic scheduling can enhance the use of PET imaging in neuro-oncology.
Article Synopsis
- Advanced characterization of primary central nervous system lymphoma (PCNSL) has led to the development of targeted therapies and emphasizes the importance of imaging techniques like PET and MRI in diagnosis and treatment monitoring.* -
- There are significant inconsistencies in clinical imaging practices and trial reporting that affect the reliability of PCNSL response assessments; therefore, an international survey was conducted to evaluate current imaging practices among clinical sites.* -
- The International PCNSL Collaborative Group (IPCG) has proposed standardized imaging recommendations that incorporate biological insights and has developed both "ideal" and "minimum standard" MRI protocols to aid researchers and clinicians in effectively implementing these guidelines.*
Article Synopsis
- CNS lymphoma can show unusual imaging features, making it hard to diagnose and start treatment promptly.
- Nonenhancing CNS lymphoma is particularly rare, occurring in about 1% of cases.
- The study discusses three cases of this type in patients with healthy immune systems, highlighting the usefulness of diffusion- and perfusion-weighted imaging for diagnosis.
Article Synopsis
- The study aimed to compare the effectiveness of ferumoxytol-enhanced MRI against standard gadolinium-enhanced MRI in detecting intracranial metastatic disease by looking at the number and size of lesions in patients.
- A total of 19 patients with different types of cancers had their MR images analyzed by two neuroradiologists, who independently assessed lesions identified with both imaging techniques.
- The results indicated that ferumoxytol-enhanced MRI was equally effective as gadolinium-enhanced MRI for detecting brain metastases, suggesting it could be a useful alternative for patient monitoring and diagnosis.
Article Synopsis
- Glioblastoma is a highly aggressive brain cancer with varied characteristics, making it difficult to develop effective personalized treatments; addressing intratumoral heterogeneity is key to better tumor classification.
- Researchers used transcriptional profiles from glioblastoma samples to enhance patient stratification by focusing on the cellular tumor structure for more accurate analysis.
- The study demonstrates that analyzing pure cellular tumor tissue can improve biomarker effectiveness, aiding in diagnostics, prognostics, and treatment strategies for glioblastoma patients.
Article Synopsis
- * The review examines existing research on liquid biopsy specifically in pediatric and adult gliomas, focusing on high-grade cases.
- * Although still in early stages, advancements in detecting liquid biomarkers for pHGG could significantly enhance the development of liquid biopsy techniques in neuro-oncology.
Article Synopsis
- Noninvasive differentiation between therapy-induced pseudoprogression and actual disease recurrence in glioblastoma patients is challenging without specific imaging metrics.
- This study analyzed MRI results using ferumoxytol and gadolinium contrast in 45 glioblastoma patients, focusing on how these contrasts can serve as biomarkers by measuring enhancement mismatch ratios.
- Results indicated that the ferumoxytol to gadolinium mismatch ratios can effectively distinguish between pseudoprogression and disease recurrence, showing 100% sensitivity and specificity, particularly in differentiating responses based on IDH-1 mutational status.
Article Synopsis
- Spin-lattice relaxation in the rotating frame (SLRRF) is a technique used in magnetic resonance imaging (MRI) to measure differences in tissue characteristics, particularly in glioblastoma.
- A case of an 84-year-old man with a brain mass showed that SLRRF metrics helped diagnose glioblastoma after an initial tissue sample was inconclusive.
- This case emphasizes the effectiveness of SLRRF MRI in detecting aggressive tumor regions, aiding in better characterization of glioblastoma heterogeneity.
Article Synopsis
- The study aimed to quantitatively compare the enhancement of T-weighted images using two contrast agents, ferumoxytol and gadoteridol, in high grade glioma patients.
- A total of 206 post-gadoteridol and 24-hour post-ferumoxytol scans from 58 patients were analyzed to calculate enhancement volumes and signal intensities.
- Results showed that ferumoxytol had smaller enhancement volume (13.83% less) and lower signal intensity (7.24% less) compared to gadoteridol, but the differences were consistent across various treatment groups, supporting the use of ferumoxytol for imaging gliomas.