Spatial analysis of acoustic noise transfer function with a human-body phantom in a clinical MRI scanner.

Background: The acoustic noise in magnetic resonance imaging (MRI) potentially depends on the measurement position and presence of a patient inside the scanner bore.

Purpose: To analyze the spatial characteristics of the acoustic noise by using the gradient-pulse-to-acoustic-noise transfer function (GPAN-TF) with and without a human-body phantom on the examination table.

Material And Methods: Acoustic noise waveforms were acquired at 80 and 110 measurement positions with and without a phantom.

Evaluation of motion artifacts in brain magnetic resonance images using convolutional neural network-based prediction of full-reference image quality assessment metrics.

Motion artifacts in magnetic resonance (MR) images mostly undergo subjective evaluation, which is poorly reproducible, time consuming, and costly. Recently, full-reference image quality assessment (FR-IQA) metrics, such as structural similarity (SSIM), have been used, but they require a reference image and hence cannot be used to evaluate clinical images. We developed a convolutional neural network (CNN) model to quantify motion artifacts without using reference images.

Fast Phase-Contrast Cine MRI for Assessing Intracranial Hemodynamics and Cerebrospinal Fluid Dynamics.

We propose fast phase-contrast cine magnetic resonance imaging (PC-cine MRI) to allow breath-hold acquisition, and we compared intracranial hemo- and hydrodynamic parameters obtained during breath holding between full inspiration and end expiration. On a 3.0 T MRI, using electrocardiogram (ECG)-synchronized fast PC-cine MRI with parallel imaging, rectangular field of view, and segmented k-space, we obtained velocity-mapped phase images at the mid-C2 level with different velocity encoding for transcranial blood flow and cerebrospinal-fluid (CSF) flow.

[Comparison of image distortion between three magnetic resonance imaging systems of different magnetic field strengths for use in stereotactic irradiation of brain].

In this study, we evaluated the image distortion of three magnetic resonance imaging (MRI) systems with magnetic field strengths of 0.4 T, 1.5 T and 3 T, during stereotactic irradiation of the brain.

Qualitative near-infrared vascular imaging system with tuned aperture computed tomography.

We developed a novel system for imaging and qualitatively analyzing the surface vessels using near-infrared (NIR) radiation using tuned aperture computed tomography (TACT(®)). The system consisted of a NIR-sensitive CCD camera surrounded by sixty light emitting diodes (with wavelengths alternating between 700 or 810 nm). This system produced thin NIR tomograms, under 0.

Acoustic noise transfer function in clinical MRI a multicenter analysis.

Rationale And Objectives: Acoustic noise both in terms of its magnitude and frequency during magnetic resonance imaging (MRI) scan is influenced by imaging parameters and pulse sequences. It varies because of many different factors such as structure, materials, and magnetic field strength. The purpose of our study is to evaluate the characteristics of acoustic noise independent of MRI scan protocol by measuring a gradient-pulse-to-acoustic-noise transfer function (GPAN-TF) at various MRI scanners.

A patient with primary biliary cirrhosis complicated with slowly progressive insulin-dependent diabetes mellitus.

We report a case of primary biliary cirrhosis (PBC) complicated by slowly progressive insulin-dependent diabetes mellitus (SPIDDM). A 67-year-old woman was diagnosed as having PBC based on clinical manifestations and a positive result of anti-mitochondrial antibody. Furthermore, SPIDDM was diagnosed by her clinical course and a positive result of anti-glutamic acid decarboxylase antibody.