Application of deep learning techniques for breath-hold, high-precision T2-weighted magnetic resonance imaging of the abdomen.

Purpose: To evaluate the feasibility of a high-precision single-shot fast spin-echo (SS-FSE) sequence using the deep learning-based Precise IQ Engine (PIQE) algorithm in comparison with standard SS-FSE for T2-weighted MR imaging of the abdomen, and to compare the image quality with a multi-shot (MS)-FSE sequence using the PIQE algorithm.

Methods: This retrospective study included 105 patients who underwent abdominal MR including T2-weighted sequences using the PIQE reconstruction algorithm. The image quality, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) in high-precision SS-FSE sequences using PIQE were compared to those in standard SS-FSE without PIQE and MS-FSE sequences using PIQE.

High-precision MRI of liver and hepatic lesions on gadoxetic acid-enhanced hepatobiliary phase using a deep learning technique.

Purpose: The purpose of this study was to investigate whether the high-precision magnetic resonance (MR) sequence using modified Fast 3D mode wheel and Precise IQ Engine (PIQE), that was collected in a wheel shape with sequential data filling in the k-space in the phase encode-slice encode plane, is feasible for breath-hold (BH) three-dimensional (3D) T1-weighted imaging of the hepatobiliary phase (HBP) of gadoxetic acid-enhanced MRI in comparison to the compressed sensing (CS) sequence using Advanced Intelligent Clear-IQ Engine (AiCE).

Methods: This retrospective study included 54 patients with focal hepatic lesions who underwent dynamic contrast-enhanced MRI. Both standard HBP images using CS with AiCE and high-precision HBP images using modified Fast 3D mode wheel and PIQE were obtained.

Image quality in three-dimensional (3D) contrast-enhanced dynamic magnetic resonance imaging of the abdomen using deep learning denoising technique: intraindividual comparison between T1-weighted sequences with compressed sensing and with a modified Fast 3D mode wheel.

Purpose: To assess the image quality of a modified Fast three-dimensional (Fast 3D) mode wheel with sequential data filling (mFast 3D wheel) combined with a deep learning denoising technique (Advanced Intelligent Clear-IQ Engine [AiCE]) in contrast-enhanced (CE) 3D dynamic magnetic resonance (MR) imaging of the abdomen during a single breath hold (BH) by intra-individual comparison with compressed sensing (CS) with AiCE.

Methods: Forty-two patients who underwent multiphasic CE dynamic MRI obtained with both mFast 3D wheel using AiCE and CS using AiCE in the same patient were retrospectively included. The conspicuity, artifacts, image quality, signal intensity ratio (SIR), signal-to-noise ratio (SNR), contrast ratio (CR), and contrast enhancement ratio (CER) of the organs were compared between these 2 sequences.

Dual-Source Contrast-Enhanced Multiphasic CT of the Liver Using Low Voltage (70 kVp): Feasibility of a Reduced Radiation Dose and a 50% of Contrast Dose.

This study investigated the feasibility of both a reduced radiation dose and a 50% of contrast dose in multiphasic CT of the liver with a 70 kVp protocol compared with a standard-tube-voltage protocol derived from dual-energy (DE) CT (blended DE protocol) with a full-dose contrast-agents in the same patient group. This study included 46 patients who underwent multiphasic contrast-enhanced dynamic CT of the liver with both a 70 kVp and a blended DE protocols. For quantitative analysis, median CT values for the liver, aorta, and portal vein, as well as signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR), were measured and calculated.

Portal vein embolization via the ipsilateral percutaneous transhepatic approach versus laparotomic transileocecal approach: complications, profile and changes in future liver remnant volume.

Objective: Major liver resection is an effective treatment option for patients with liver malignancy. The future liver remnant (FLR) volume and complications after portal vein embolization (PVE) were compared between the ipsilateral right portal vein (PTPE) and transileocolic (TIPE) approaches.

Methods: A total of 42 patients (TIPE, = 22; PTPE, = 20) underwent right lobectomy after PVE.

Assessment of gastric wall structure using ultra-high-resolution computed tomography.

Purpose: To evaluate the image quality of ultra-high-resolution CT (U-HRCT) in the comparison among four different reconstruction methods, focusing on the gastric wall structure, and to compare the conspicuity of a three-layered structure of the gastric wall between conventional HRCT (C-HRCT) and U-HRCT.

Method: Our retrospective study included 48 patients who underwent contrast-enhanced U-HRCT. Quantitative analyses were performed to compare image noise of U-HRCT between deep-learning reconstruction (DLR) and other three methods (filtered back projection: FBP, hybrid iterative reconstruction: Hybrid-IR, and Model-based iterative reconstruction: MBIR).

Reduced Field-of-View Diffusion-Weighted Magnetic Resonance Imaging of the Pancreas With Tilted Excitation Plane: A Preliminary Study.

Background: Reduced field-of-view diffusion-weighted imaging (rDWI) with tilted two-dimensional radiofrequency (RF) excitation planes has not yet been applied to the imaging of the pancreas although the utility of this technique which allows the acquisition of high-quality images without aliasing artifacts in the phase-encoding direction has been evaluated for brain and spinal cord imaging.

Purpose: To evaluate the visual image quality of the pancreas by tilting the excitation plane (tilted rDWI) in comparison to conventional DWI (cDWI) and rDWI without using the tilted excitation plane.

Study Type: Retrospective.

Transient respiratory motion artifacts in multiple arterial phases on abdominal dynamic magnetic resonance imaging: a comparison using gadoxetate disodium and gadobutrol.

Purpose: To compare the occurrence of transient respiratory motion artifacts (TRMAs) in multiple arterial phases on abdominal magnetic resonance (MR) images between those obtained using gadobutrol and gadoxetate disodium.

Materials And Methods: Two hundred and fourteen abdominal MR examinations (101 with gadoxetate disodium, 113 with gadobutrol) were evaluated. Dynamic three-dimensional contrast-enhanced T1-weighted imaging (CAIPIRINHA-Dixon-TWIST-VIBE) including single-breath-hold six arterial phase acquisitions was performed on a 3.

Image quality in dual-source multiphasic dynamic computed tomography of the abdomen: evaluating the effects of a low tube voltage (70 kVp) in combination with contrast dose reduction.

Purpose: To compare the image quality of multiphasic (arterial, portal, and equilibrium phases) dynamic computed tomography (CT) of the abdomen obtained by a low tube voltage (70kVp) in combination with a half-dose iodine load using low-concentration contrast agent in high tube output dual-source CT with a standard tube voltage (120kVp) and full-dose iodine load using the same group of adult patients.

Methods: Fifty-five patients who underwent both low-tube-voltage (70kVp) abdominal CT with a half-dose iodine load and standard-tube-voltage (120kVp) CT with a full-dose iodine load were analyzed. The mean CT values and signal-to-noise ratio (SNR) of the liver, aorta and portal veins were quantitatively assessed.

Incidentally detected pancreatic adenocarcinomas on computed tomography obtained during the follow-up for other diseases.

Purpose: To determine imaging findings of pancreatic adenocarcinomas incidentally detected on contrast-enhanced multiphasic dynamic computed tomography (CT) obtained during the follow-up for other diseases.

Methods: From January 2007 to December 2018, 14 patients with pancreatic adenocarcinomas incidentally detected on CT obtained during the follow-up for other diseases (incidental group) and 105 patients with pancreatic adenocarcinomas symptomatically detected on ultrasound or CT (non-incidental group) were included. Imaging characteristics of the tumor were compared between the two groups.

Liver imaging reporting and data system (LI-RADS) v2018: comparison between computed tomography and gadoxetic acid-enhanced magnetic resonance imaging.

Purpose: To determine the consistency of major hepatocellular carcinoma (HCC) features between CT and MRI based on Liver Imaging Reporting and Data System (LI-RADS) v2018 and to investigate the additional value on gadoxetic acid-enhanced MRI.

Materials And Methods: Patients who underwent dynamic CT and gadoxetic acid-enhanced MRI within 1 month were investigated. Two radiologists evaluated the presence of major HCC features and categorized observations using LI-RADS v2018 algorithm.