Publications by authors named "Yoneyama M"
New non-contrast MRI of endolymphatic hydrops in Ménière's disease considering inversion time.
Laryngoscope Investig Otolaryngol
August 2024
Objectives: Three-tesla MRI with gadolinium-based contrast agents is important in diagnosing Ménière's disease. However, contrast agents cannot be used in some patients. By using the compositional difference between the inner ear endolymph and perilymph, we performed basic and clinical research focused on potassium ions and protein to find the optimal parameters for visualizing endolymphatic hydrops on MRI without contrast.
View Article and Find Full Text PDFArticle Synopsis
- The study aimed to evaluate the effectiveness of model-based deep learning reconstruction (DL-DWI) in improving prostate diffusion-weighted imaging (DWI) compared to traditional parallel imaging (PI-DWI).
- Researchers analyzed 32 patients with prostate cancer and found that DL-DWI significantly outperformed PI-DWI in terms of image quality, as shown by both qualitative and quantitative measures.
- The results indicated that DL-DWI provided better signal-to-noise ratio, contrast-to-noise ratio, and diffusion coefficient values for prostate tissues and lesions; however, the study lacked comparisons with other deep learning methods, highlighting a need for future research.
Article Synopsis
- This study aimed to evaluate how well lenticulostriate arteries (LSAs) can be seen using advanced imaging techniques, specifically comparing deep learning-based reconstruction with traditional methods.
- It involved five healthy volunteers and analyzed high-resolution images with varying levels of data reduction to assess the visibility and quality of LSAs as recognized by radiologists.
- Results showed that deep learning reconstruction improved the visibility and quality of LSAs compared to conventional methods, particularly at higher data reduction levels, making it a potentially better option for medical imaging.
Background And Purpose: Symptomatic radiation pneumonitis (SRP) is a complication of thoracic stereotactic body radiotherapy (SBRT). As visual assessments pose limitations, artificial intelligence-based quantitative computed tomography image analysis software (AIQCT) may help predict SRP risk. We aimed to evaluate high-resolution computed tomography (HRCT) images with AIQCT to develop a predictive model for SRP.
View Article and Find Full Text PDFPurpose: Quantitative MRI techniques such as T2 mapping are useful in comprehensive evaluation of various pathologies of the knee joint yet require separate scans to conventional morphological measurements and long acquisition times. The recently introduced 3D MIXTURE (Multi-Interleaved X-prepared Turbo-Spin Echo with Intuitive Relaxometry) technique can obtain simultaneous morphologic and quantitative information of the knee joint. To compare MIXTURE with conventional methods and to identify differences in morphological and quantitative information.
View Article and Find Full Text PDFArticle Synopsis
- The study evaluated a new imaging technique called MIXTURE, used for assessing cartilage and meniscus in knee specimens, compared to traditional turbo spin-echo (TSE) sequences.
- Standardized cartilage defects were created in human cadaver knees, and both MIXTURE and TSE sequences were analyzed for their effectiveness in showing defects and measuring relaxation times.
- The results showed that while both imaging methods had comparable visual results, MIXTURE provided a time-efficient way to obtain useful quantitative data on cartilage conditions.
Quantitative MRI techniques such as T2 and T1ρ mapping are beneficial in evaluating knee joint pathologies; however, long acquisition times limit their clinical adoption. MIXTURE (Multi-Interleaved X-prepared Turbo Spin-Echo with IntUitive RElaxometry) provides a versatile turbo spin-echo (TSE) platform for simultaneous morphologic and quantitative joint imaging. Two MIXTURE sequences were designed along clinical requirements: "MIX1", combining proton density (PD)-weighted fat-saturated (FS) images and T2 mapping (acquisition time: 4:59 min), and "MIX2", combining T1-weighted images and T1ρ mapping (6:38 min).
View Article and Find Full Text PDFArticle Synopsis
- The study evaluates a new imaging technique called MIXTURE, developed by Philips, which produces high-resolution T2 maps for diagnosing cervical radiculopathy.
- It compares T2 relaxation times and their variability using MIXTURE with another method, SHINKEI-Quant (S-Q), in both healthy participants and a patient with cervical disc herniation.
- Results show that MIXTURE provides significantly shorter T2 relaxation times and lower variability in measurements, indicating its potential for more accurate preoperative functional diagnosis of cervical nerve issues.
Purpose: Tumor-infiltrating lymphocytes (TILs) have prognostic significance in several cancers, including breast cancer. Despite interest in combining radiation therapy with immunotherapy, little is known about the effect of radiation therapy itself on the tumor-immune microenvironment, including TILs. Here, we interrogated longitudinal dynamics of TILs and systemic lymphocytes in patient samples taken before, during, and after neoadjuvant radiation therapy (NART) from PRADA and Neo-RT breast clinical trials.
View Article and Find Full Text PDFRNA silencing is a post-transcriptional gene-silencing mechanism mediated by microRNAs (miRNAs). However, the regulatory mechanism of RNA silencing during viral infection is unclear. TAR RNA-binding protein (TRBP) is an enhancer of RNA silencing that induces miRNA maturation by interacting with the ribonuclease Dicer.
View Article and Find Full Text PDFArticle Synopsis
- The study aims to improve diffusion-weighted imaging (DWI) in diagnostic radiology by tackling issues related to low signal-to-noise ratio (SNR) in high b-value images and biases in apparent diffusion coefficient (ADC) values through deep learning techniques.
- Researchers evaluated various reconstruction methods, including traditional parallel imaging and advanced AI-based techniques, using both commercial diffusion phantoms and numerical simulations, measuring their effectiveness across different acceleration factors and flip angles.
- Results indicated that lower SNR led to increased negative bias and reduced precision in ADC measurements, but the deep learning-based method (C-SENSE AI) showed significant improvements in denoised ADC maps compared to conventional methods, particularly at high acceleration and low flip angles.
RIG-I-like receptors (RLRs) are crucial for pathogen detection and triggering immune responses and have immense physiological importance. In this review, we first summarize the interferon system and innate immunity, which constitute primary and secondary responses. Next, the molecular structure of RLRs and the mechanism of sensing non-self RNA are described.
View Article and Find Full Text PDFPurpose: Prolonged scanning of time-resolved 3D phase-contrast MRI (4D flow MRI) limits its routine use in clinical practice. An echo-planar imaging (EPI)-based sequence and compressed sensing can reduce the scan duration. We aimed to determine the impact of EPI for 4D flow MRI on the scan duration, image quality, and quantitative flow metrics.
View Article and Find Full Text PDFArticle Synopsis
- Centrally located lung tumors pose challenges due to symptoms like airway obstruction and bleeding, and surgical removal often necessitates sacrificing lung tissue, making radiotherapy a preferred treatment.
- A study is being conducted using a dual-method approach of deep inspiration breath-hold (DIBH) and adaptive radiotherapy to improve the safety and efficacy of treating these tumors.
- The goal of the study is to evaluate the incidence of severe adverse events from this treatment approach, which may lead to advancements in radiotherapy methods for lung tumors if successful.
Purpose: Neuromelanin is visualized by optimizing the conditions of longitudinal relaxation (T1)-weighted imaging (T1WI). Although it was originally developed in 2D imaging, 3D imaging has been also reported, and T1WI sequences with magnetization transfer (MT) pulses are now widely used in 3D gradient echo (GRE) sequences. In this study, we assert that the use of spectral presaturation with inversion recovery (SPIR) may also be useful as an alternative to MT pulses, and we optimize SPIR and compare it with MT.
View Article and Find Full Text PDFArticle Synopsis
- This study compared the image quality of two types of diffusion-weighted imaging (DWI) techniques: echo planar imaging with compressed sensing-sensitivity encoding (EPICS-DWI) and conventional parallel imaging (PI-DWI) in healthy volunteers.
- Results showed that EPICS-DWI produced significantly higher signal-to-noise ratios (SNR) and better overall image quality at acceleration factors of 3 and 4 when compared to PI-DWI, although there were no significant differences in apparent diffusion coefficients (ADC) between the two methods.
- Despite EPICS-DWI showing improved quality, it also displayed a higher degree of image distortion at lower acceleration factors, indicating that optimal parameter settings are crucial for achieving the best imaging results.
Sensorineural hearing loss (SNHL) induced by noise has increased in recent years due to personal headphone use and noisy urban environments. The study shows a novel model of gradually progressive SNHL induced by repeated exposure to moderate noise (8-kHz octave band noise, 90-dB sound pressure level) for 1 hr exposure per day in BALB/cCr mice. The results showed that the repeated exposure led to gradually progressive SNHL, which was dependent on the number of exposures, and resulted in permanent hearing loss after 5 exposures.
View Article and Find Full Text PDFArticle Synopsis
- The study aimed to compare deep learning (DL)-based image reconstruction with traditional compressed sensing (CS) methods for enhancing fat-suppressed contrast-enhanced 3D T1-weighted images (T1WIs) of the head and neck.
- Researchers analyzed images from 39 patients and evaluated them qualitatively (image quality, anatomical structure visibility, etc.) and quantitatively (signal-to-noise ratios and contrast-to-noise ratios).
- Results showed that DL-based reconstruction significantly improved image quality and quantitative metrics, suggesting it is a more effective technique for assessing head and neck conditions than conventional CS methods.
Article Synopsis
- This study evaluated the use of liver MR fingerprinting (MRF) to quantitatively assess and diagnose different focal liver lesions in 89 participants averaging 62 years old.
- The MRF measurements performed comparably to standard MRI assessments, showing strong agreement for T1 values and moderate for T2, while also demonstrating good repeatability across measurements.
- A combination of metrics derived from MRF distinguished between benign and malignant lesions effectively, achieving a high diagnostic accuracy with an area under the curve (AUC) of 0.92.
Article Synopsis
- Kawasaki disease is a systemic vasculitis that requires the evaluation of both coronary and systemic arteries, and this study aimed to assess the effectiveness of non-contrast magnetic resonance angiography (NC-MRA) in detecting complications related to the disease.* -
- The study involved 28 patients, with 57 exams focused on coronary arteries and 42 exams that included both coronary and systemic artery assessments, finding high image quality for various systemic arteries.* -
- Results showed no significant differences in examination time or sedation dosages between protocols and identified systemic artery aneurysms in 7.1% of patients, demonstrating the feasibility of a combined examination approach.*
Article Synopsis
- The study aimed to evaluate how effective deep learning (DL) image reconstruction is compared to traditional parallel imaging (PI) in head and neck diffusion-weighted imaging (DWI).
- Researchers analyzed data from 41 patients, focusing on qualitative aspects like image quality and artifacts, as well as quantitative metrics such as signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR).
- Results showed that DL-based reconstructions significantly outperformed PI-based reconstructions in both qualitative and quantitative assessments, indicating DL's potential to improve image quality in head and neck imaging.
Background: The failure of frozen-thawed blastocysts to re-expand adequately within a few hours after warming has been reported to have a negative impact on assisted reproductive technology (ART) outcomes. However, the extent to which this failure truly affects ART outcomes has not yet been presented in a manner that is easily understandable to medical practitioners and patients. This study aimed to assess the effects of blastocyst shrinkage on ART outcomes and determine a more effective morphological evaluation approach for use in clinical settings.
View Article and Find Full Text PDFPurpose: To assess the reproducibility of ADC, T1, T2, and proton density (PD) measurements on the cortex across the entire brain using high-resolution pseudo-3D diffusion-weighted imaging using echo-planar imaging with compressed SENSE (EPICS-DWI) and 3D quantification with an interleaved Look-Locker acquisition sequence with T2 preparation pulse (3D-QALAS) in normal healthy adults.
Methods: Twelve healthy participants (median age, 33 years; range, 28-51 years) were recruited to evaluate the reproducibility of whole-brain EPICS-DWI and synthetic MRI. EPICS-DWI utilizes a compressed SENSE reconstruction framework while maintaining the EPI sampling pattern.