Whole Process of Standardization of Diffusion-Weighted Imaging: Phantom Validation and Clinical Application According to the QIBA Profile.

To use the apparent diffusion coefficient (ADC) as reliable biomarkers, validation of MRI equipment performance and clinical acquisition protocols should be performed prior to application in patients. This study aims to validate various MRI equipment and clinical brain protocols for diffusion weighted imaging (DWI) using commercial phantom, and confirm the validated protocols in patients' images. The performance of four different scanners and clinical brain protocols were validated using a Quantitative Imaging Biomarker Alliance (QIBA) diffusion phantom and cloud-based analysis tool.

Automated segmentation of the fractured vertebrae on CT and its applicability in a radiomics model to predict fracture malignancy.

Although CT radiomics has shown promising results in the evaluation of vertebral fractures, the need for manual segmentation of fractured vertebrae limited the routine clinical implementation of radiomics. Therefore, automated segmentation of fractured vertebrae is needed for successful clinical use of radiomics. In this study, we aimed to develop and validate an automated algorithm for segmentation of fractured vertebral bodies on CT, and to evaluate the applicability of the algorithm in a radiomics prediction model to differentiate benign and malignant fractures.

Prediction of the Acuity of Vertebral Compression Fractures on CT Using Radiologic and Radiomic Features.

Rationale And Objectives: To develop and validate prediction models to differentiate acute and chronic vertebral compression fractures based on radiologic and radiomic features on CT.

Materials And Methods: This study included acute and chronic compression fractures in patients who underwent both spine CT and MRI examinations. For each fractured vertebra, three CT findings ([1] cortical disruption, [2] hypoattenuating cleft or sclerotic line, and [3] relative bone marrow attenuation) were assessed by two radiologists.

Incidence of Immune-Mediated Pseudoprogression of Lymphoma Treated with Immune Checkpoint Inhibitors: Systematic Review and Meta-Analysis.

We evaluated the incidence of pseudoprogression and indeterminate response (IR) in patients with lymphoma treated with immune checkpoint inhibitors (ICIs). A systematic search of PubMed and EMBASE was performed up to 6 February 2021, using the keywords "lymphoma," "immunotherapy," and "pseudoprogression." Random-effects models were used to calculate both pooled incidence of pseudoprogression patients with lymphoma and an IR according to LYRIC criteria, while the Higgins inconsistency index (I2) test and Cochran's Q test were used for heterogeneity.

Photothermal therapy via a gold nanoparticle-coated stent for treating stent-induced granulation tissue formation in the rat esophagus.

Minimally invasive therapies using stent technology are currently limited by stent-induced granulation tissue formation adjacent to the stent. The effectiveness of photothermal therapy (PTT) using a gold nanoparticle (AuNP)-coated stent for treating stent-induced granulation tissue formation in the rat esophagus was investigated. All experiments were approved by the animal research committee of our institution.

CDISC-compliant clinical trial imaging management system with automatic verification and data Transformation: Focusing on tumor response assessment data in clinical trials.

Objective: Major issues in imaging data management of tumor response assessment in clinical trials include high human errors in data input and unstandardized data structures, warranting a new breakthrough IT solution. Thus, we aim to develop a Clinical Data Interchange Standards Consortium (CDISC)-compliant clinical trial imaging management system (CTIMS) with automatic verification and transformation modules for implementing the CDISC Study Data Tabulation Model (SDTM) in the tumor response assessment dataset of clinical trials.

Materials And Methods: In accordance with various CDISC standards guides and Response Evaluation Criteria in Solid Tumors (RECIST) guidelines, the overall system architecture of CDISC-compliant CTIMS was designed.

Combined radiomics-clinical model to predict malignancy of vertebral compression fractures on CT.

Objectives: To develop and validate a combined radiomics-clinical model to predict malignancy of vertebral compression fractures on CT.

Methods: One hundred sixty-five patients with vertebral compression fractures were allocated to training (n = 110 [62 acute benign and 48 malignant fractures]) and validation (n = 55 [30 acute benign and 25 malignant fractures]) cohorts. Radiomics features (n = 144) were extracted from non-contrast-enhanced CT images.

Tract ablation after radiofrequency ablation to prevent viable tumor cell adhesion to the needle electrode.

Purpose: To evaluate whether the additive needle tract ablation (TA) can reduce adherent cells on the needle tract after radiofrequency ablation (RFA) in a preclinical HCC mouse model.

Methods: Hep3B-Luc cells were engrafted in the Balb/c-nude mice. Nineteen mice were randomly assigned into three groups: the needle only group (needle placement only without performing RFA), the RFA only group (needle placement with active RFA treatment), and the RFA-TA group (needle placement with active RFA treatment and additive tract ablation).

Percutaneous antegrade removal of foreign bodies in the urinary tract: a 20-year, single-center experience.

Background: While removing urinary tract foreign bodies is mostly performed through retrograde cystoscopy, antegrade removal using interventional procedures is reported less frequently.

Purpose: To evaluate the safety and effectiveness of percutaneous antegrade removal of urinary tract foreign bodies.

Material And Methods: A total of 14 consecutive patients (age range 9-80 years) who percutaneous antegrade removal of urinary tract foreign bodies between January 2001 and March 2020 were reviewed.

Test-retest repeatability of ultrasonographic shear wave elastography in a rat liver fibrosis model: toward a quantitative biomarker for preclinical trials.

Purpose: This study evaluated the test-retest repeatability and measurement variability of ultrasonographic shear wave elastography (SWE) for liver stiffness in a rat liver fibrosis model.

Methods: In 31 Sprague-Dawley rats divided into three groups (high-dose, low-dose, and control), liver fibrosis was induced by intraperitoneal administration of thioacetamide for 8 weeks. A dedicated radiographer performed SWE to measure liver stiffness in kilopascals in two sessions at a 3-day interval.

Temporary percutaneous radiologic gastrojejunostomy with single gastropexy.

Background: Although the effectiveness of percutaneous radiologic gastrojejunostomy (PRGJ) has been reported, a detailed description of the indications and clinical effectiveness of temporary PRGJ is still limited.

Purpose: To evaluate the clinical effectiveness and technical feasibility of temporary PRGJ using the modified Chiba-needle technique with single gastropexy.

Material And Methods: Temporary PRGJ using the modified Chiba-needle technique with single gastropexy was performed in 27 consecutive patients (19 men, 8 women; mean age = 61 years; age range = 32-77 years) for esophageal perforation (n = 18) or postoperative gastroparesis (n = 9).

Gadoxetate-enhanced dynamic contrast-enhanced MRI for evaluation of liver function and liver fibrosis in preclinical trials.

Background: To facilitate translational drug development for liver fibrosis, preclinical trials need to be run in parallel with clinical research. Liver function estimation by gadoxetate-enhanced dynamic contrast-enhanced MRI (DCE-MRI) is being established in clinical research, but still rarely used in preclinical trials. We aimed to evaluate feasibility of DCE-MRI indices as translatable biomarkers in a liver fibrosis animal model.

Balloon-Expandable Biodegradable Stents Versus Self-Expandable Metallic Stents: A Comparison Study of Stent-Induced Tissue Hyperplasia in the Rat Urethra.

Purpose: To compare the degrees of stent-induced tissue hyperplasia of balloon-expandable, biodegradable stents (BEBSs) with those of self-expandable metallic stents (SEMSs) in a rat urethral model.

Materials And Methods: A total of 20 rats were randomized into two groups. The BEBS group (n = 10) received a poly-l-lactic acid (PLLA) biodegradable stent.

In Vivo Fluorescence Microendoscopic Monitoring of Stent-Induced Fibroblast Cell Proliferation in an Esophageal Mouse Model.

Purpose: To evaluate the feasibility of self-expanding metal stent (SEMS) placement and fluorescence microendoscopic monitoring for determination of fibroblast cell proliferation after stent placement in an esophageal mouse model.

Materials And Methods: Twenty fibroblast-specific protein (FSP)-1 green fluorescent protein (GFP) transgenic mice were analyzed. Ten mice (Group A) underwent SEMS placement, and fluoroscopic and fluorescence microendoscopic images were obtained biweekly until 8 weeks thereafter.

Evaluation of drug mechanism and efficacy of a novel anti-angiogenic agent, TTAC-0001, using multi-modality bioimaging in a mouse breast cancer orthotopic model.

Purpose: Targeting of vascular endothelial growth factor receptors (VEGFRs) has potential anti-angiogenic effects because VEGFR-2 is the major signaling regulator of VEGF/VEGFR pathways. We aimed to elucidate the drug mechanism and anti-tumor efficacy of TTAC-0001, a novel, fully human anti-VEGFR-2/KDR monoclonal antibody, in mouse orthotopic breast cancer model using multi-modal bioimaging.

Materials And Methods: We used orthotopic xenograft tumor model in which human breast cancer cells (MDA-MB-231) were injected into the right mammary fat pad of Balb/c nude mice.

Direct Synthesis of Carbon Nanotube Field Emitters on Metal Substrate for Open-Type X-ray Source in Medical Imaging.

We report the design, fabrication and characterization of a carbon nanotube enabled open-type X-ray system for medical imaging. We directly grew the carbon nanotubes used as electron emitter for electron gun on a non-polished raw metallic rectangular-rounded substrate with an area of 0.1377 cm² through a plasma enhanced chemical vapor deposition system.

Radiation-induced esophageal strictures treated with fluoroscopic balloon dilation: clinical outcomes and factors influencing recurrence in 62 patients.

Background Balloon dilation is safe and effective for the treatment of radiation-induced esophageal stricture (RIES), with favorable short-term and mid-term outcomes; however, few reports of long-term outcomes exist. Few studies have evaluated factors associated with recurrence after balloon dilation. Purpose To evaluate the long-term outcome of balloon dilation in patients with RIES and to identify factors associated with stricture recurrence.

Fluoroscopic-guided stent placement in failed tentative endoscopic approaches to malignant gastroduodenal obstructions.

Background Fluoroscopic or endoscopic placement of metallic stents is used as a safe, non-surgical, palliative treatment option for malignant gastroduodenal obstructions. However, endoscopic stent placement is not always feasible, due to the tight or tortuous stricture of the obstructed area and insufficient visualization of the stomach due to remnant food material. Purpose To assess the technical feasibility and clinical outcomes of fluoroscopic-guided stent placement in malignant gastroduodenal obstructions following the technical failure of endoscopic stent placement.

Overlapping self-expandable metallic stent for palliation of a long (>10 cm) malignant gastroduodenal obstruction.

Background Self-expandable metallic stent (SEMS) placement is a well-established palliative treatment approach for malignant gastroduodenal obstruction. In patients with a long (>10 cm) stricture, multiple stents placed in an overlapping fashion are often required. Purpose To investigate the outcomes of overlapping SEMS placement for the palliative treatment of malignant gastroduodenal obstruction in patients with a long (>10 cm) stricture.

Removal of Retrievable Self-Expandable Metallic Tracheobronchial Stents: An 18-Year Experience in a Single Center.

Purpose: The purpose of the study was to retrospectively evaluate the technical outcomes of removal of retrievable self-expandable metallic stents (REMSs) and identify predictors of technical failure in 81 patients with benign and malignant tracheobronchial strictures.

Materials And Methods: A total of 98 REMSs were removed under fluoroscopic guidance in 81 patients with benign (n = 48) or malignant (n = 33) tracheobronchial strictures. Primary and secondary technical success rates and complication rate were evaluated.

Fluoroscopic removal of retrievable self-expandable metal stents in patients with malignant oesophageal strictures: Experience with a non-endoscopic removal system.

Objectives: To evaluate clinical outcomes of fluoroscopic removal of retrievable self-expandable metal stents (SEMSs) for malignant oesophageal strictures, to compare clinical outcomes of three different removal techniques, and to identify predictive factors of successful removal by the standard technique (primary technical success).

Methods: A total of 137 stents were removed from 128 patients with malignant oesophageal strictures. Primary overall technical success and removal-related complications were evaluated.

Incidence and management of oesophageal ruptures following fluoroscopic balloon dilatation in children with benign strictures.

Objectives: The purpose of this study is to investigate the incidence and management of oesophageal ruptures following fluoroscopic balloon dilatation (FBD) in children with benign oesophageal strictures.

Methods: Sixty-two children with benign oesophageal strictures underwent FBDs. Oesophageal rupture was categorized as intramural (type 1), transmural (type 2), or transmural with free leakage (type 3).

Preliminary Results of Percutaneous Radiologic Gastrostomy in a Pediatric Population: A Modified Chiba-Needle Puncture Technique With Single Gastropexy.

Objective: The purpose of this study was to evaluate the technical feasibility, safety, and clinical effectiveness of percutaneous radiologic gastrostomy using a modified Chiba-needle puncture technique with single gastropexy in pediatric patients.

Materials And Methods: From July 2006 to December 2013, percutaneous radiologic gastrostomy was performed in 12 children (median age, 21 months; range, 6-46 months). Their stomachs were punctured using a 21-gauge Chiba needle.