The Effect of Young People-Assisted, Individualized, Motion-Based Video Games on Physical, Cognitive, and Social Frailty Among Community-Dwelling Older Adults With Frailty: Randomized Controlled Trial.

Background: The aging population highlights the need to maintain both physical and psychological well-being. Frailty, a multidimensional syndrome, increases vulnerability to adverse outcomes. Although physical exercise is effective, adherence among older adults with frailty is often low due to barriers.

The Effects of the Connecting All Generations Through the Gerontech (CARETech) Program on Motivating Young People to Enter the Elderly Care Sector.

Purpose: This study aims to organize an intergenerational program to provide unemployed young people with operational skills related to gerontechnology and the experience required to deliver digital outreach rehabilitation services to community-dwelling older people.

Methods: A quasi-experimental research design was adopted. The young participants received a 12-session training program on the management of common chronic diseases, communication with older people, the functions and use of interactive games, and techniques to teach and match interactive games with older people.

Technical note: Workload and transmission data for mobile C-arm fluoroscopy in gastrointestinal endoscopy.

Background: Mobile C-arms may be used in fixed locations, and it is recommended that qualified experts evaluate structural shielding.

Purpose: To assess clinical workload distributions for mobile C-arms used in gastrointestinal endoscopy and determine the Archer equation parameters for the C-arm beam spectra.

Methods: Consecutive (30 months) gastrointestinal endoscopic procedures on two Cios Alpha systems (Siemens) were retrospectively analyzed.

Neurointerventions on two generations of angiography systems: Recent systems reduce radiation exposure by half.

Purpose: Fluoroscopically-guided neurointervention may be associated with prolonged procedure time and substantial radiation exposure to the patient and staff. This study sought to examine technological features affecting the potential radiation exposure reduction of new angiography systems, compared to older systems, for neurointerventional procedures.

Methods: Consecutive neurointerventional patients (2020-2022) were retrospectively analyzed.

Cumulative radiation exposure from multimodality recurrent imaging of CT, fluoroscopically guided intervention, and nuclear medicine.

Objectives: To assess cumulative effective dose (CED) over a 4-year period in patients undergoing multimodality recurrent imaging at a major hospital in the USA.

Methods: CED from CT, fluoroscopically guided intervention (FGI), and nuclear medicine was analyzed in consecutive exams in a tertiary care center in 2018-2021. Patients with CED ≥ 100 mSv were classified by age and body habitus (underweight, healthy weight, overweight, obese), as per body mass index percentiles < 5, 5 to < 85, 85 to < 95, and ≥ 95 (age 2-19 years), and its ranges < 18.

Visualization and comparison of CT dose distribution between axial and helical acquisitions.

Background: It is challenging to assess the accuracy of volume CT Dose Index (CTDI ) when the axial scan modes corresponding to a helical scan protocol are not available. An alternative approach was proposed to directly measure using helical acquisitions and relatively small differences (< 20%) from CTDI were observed.

Purpose: To visually demonstrate the 3D dose distribution for both axial and helical CT acquisitions and quantitively compare and CTDI .

Patient follow-up for possible radiation injury from fluoroscopically-guided interventions: Need to consider high cumulative exposure from multiple procedures.

Purpose: Patient skin dose from interventional fluoroscopy procedures may exceed the threshold of tissue injuries and established guidelines recommend patient follow-up for air kerma at reference point (K) ≥ 5 Gy for individual procedures. Patients may undergo multiple procedures and skin injuries may be possible by cumulative exposure, even when individually insufficient to cause injury. This study sought to quantify the frequency of patients whose individual procedure doses are below 5 Gy but whose cumulative K is ≥ 5 Gy.

CT image quality evaluation in the age of deep learning: trade-off between functionality and fidelity.

Objective: To quantitatively compare DLIR and ASiR-V with realistic anatomical images.

Methods: CT scans of an anthropomorphic phantom were acquired using three routine protocols (brain, chest, and abdomen) at four dose levels, with images reconstructed at five levels of ASiR-V and three levels of DLIR. Noise power spectrum (NPS) was estimated using a difference image by subtracting two matching images from repeated scans.

Calculation of scan length and size-specific dose at longitudinal positions of body CT scans using dose equilibrium function.

Background: Dose evaluation at longitudinal positions of body computed tomography (CT) scans is useful for CT quality assurance programs and patient organ dose evaluation. Accurate estimates depend on both patient size and scan length.

Purpose: To propose practical evaluation of the average dose to the transverse slab of an axial image slice for adult body CT examinations, considering not only patient size but also scan length, and to compare the results with those of Monte Carlo (Geant4) simulation [D (z)] and size-specific dose estimates at longitudinal positions of scans [SSDE(z)] from international standards (IEC publication no.

Technical note: Advancing size-specific dose estimates in CT examinations: Dose estimates at longitudinal positions of scans.

Purpose: American Association of Physicists in Medicine (AAPM) (Report 204) introduced the size-specific dose estimate (SSDE) for the average dose to the center of a fixed-mA scan. International standards establish a method that CT manufacturers and radiation dose index monitoring software may use to calculate SSDE(z) at longitudinal positions of scans with fixed mA or tube current modulation, and its scan range average . We sought to test how accurate SSDE(z) is in tracking the average dose to the transverse slab of an axial image slice (D ), evaluated with Monte Carlo calculation, in the chest and abdominopelvic examinations.

Radiation exposure in 101 non-coronary fluoroscopically guided interventional procedures: reference levels of air kerma at the reference point and air kerma area product.

Objectives: To present the median value and 75th percentile of air kerma at the reference point (K), air kerma-area product (KAP), and fluoroscopic time for a large number of fluoroscopically guided interventional (FGI) procedures.

Methods: This retrospective study included the consecutive non-coronary FGI procedures from a Radiology department between May 2016 and October 2018 at a large tertiary-care hospital in the U.S.

Power Spectrum Analysis of Breast Parenchyma with Digital Breast Tomosynthesis Images in a Longitudinal Screening Cohort from Two Vendors.

Rationale And Objectives: To quantitatively compare breast parenchymal texture between two Digital Breast Tomosynthesis (DBT) vendors using images from the same patients.

Materials And Methods: This retrospective study included consecutive patients who had normal screening DBT exams performed in January 2018 from GE and normal screening DBT exams in adjacent years from Hologic. Power spectrum analysis was performed within the breast tissue region.

Patient-level dose monitoring in computed tomography: tracking cumulative dose from multiple multi-sequence exams with tube current modulation in children.

Background: In children exposed to multiple computed tomography (CT) exams, performed with varying z-axis coverage and often with tube current modulation, it is inaccurate to add volume CT dose index (CTDI) and size-specific dose estimate (SSDE) to obtain cumulative dose values.

Objective: To introduce the patient-size-specific z-axis dose profile and its dose line integral (DLI) as new dose metrics, and to use them to compare cumulative dose calculations against conventional measures.

Materials And Methods: In all children with 2 or more abdominal-pelvic CT scans performed from 2013 through 2019, we retrospectively recorded all series kV, z-axis tube current profile, CTDI, dose-length product (DLP) and calculated SSDE.

Fetal dose evaluation for body CT examinations of pregnant patients during all stages of pregnancy.

Purpose: CTDI-to-fetal-dose coefficients from Monte Carlo simulations are useful for fetal dose evaluations, but the available data is limited to the fetus being completely inside the abdominopelvic scan range. Whereas in a chest examination, the fetus is completely outside the scan range. In an abdominal examination, the fetus after 16 gestational weeks is partly in the scan region, and an earlier fetus is completely outside of it.

Experimental and numerical studies on kV scattered x-ray imaging for real-time image guidance in radiation therapy.

Motion management is a critical component of image guided radiotherapy for lung cancer. We previously proposed a scheme using kV scattered x-ray photons for marker-less real-time image guidance in lung cancer radiotherapy. This study reports our recent progress using the photon counting detection technique to demonstrate potential feasibility of this method and using Monte Carlo (MC) simulations and ray-tracing calculations to characterize the performance.

Radiation Effective Dose Above 100 mSv From Fluoroscopically Guided Intervention: Frequency and Patient Medical Condition.

The purpose of this article was to investigate the medical condition of patients who received substantial cumulative effective dose (CED) in fluoroscopically guided interventional (FGI) procedures. We examined 25,253 patients (mean age, 58.2 years; 50.

Quantitative evaluation of transmission properties of breast tissue equivalent materials under Compton scatter imaging setup.

To explore the potential of utilizing Compton scattered x-ray photons for imaging applications, it is critical to accurately evaluate scattered x-ray transmission properties of targeted tissue materials. In this study, scattered x-ray transmission of breast tissue equivalent phantoms was evaluated. Firstly, two validations were carried out using a primary x-ray beam at 80 kVp with both experimental measurement (ion chamber with narrow-beam setup) and analytical calculation (Spektr toolkit).

A method of rapid quantification of patient-specific organ doses for CT using deep-learning-based multi-organ segmentation and GPU-accelerated Monte Carlo dose computing.

Purpose: One technical barrier to patient-specific computed tomography (CT) dosimetry has been the lack of computational tools for the automatic patient-specific multi-organ segmentation of CT images and rapid organ dose quantification. When previous CT images are available for the same body region of the patient, the ability to obtain patient-specific organ doses for CT - in a similar manner as radiation therapy treatment planning - will open the door to personalized and prospective CT scan protocols. This study aims to demonstrate the feasibility of combining deep-learning algorithms for automatic segmentation of multiple radiosensitive organs from CT images with the GPU-based Monte Carlo rapid organ dose calculation.

Patients undergoing recurrent CT scans: assessing the magnitude.

Objectives: To assess percent of patients undergoing multiple CT exams that leads to cumulative effective dose (CED) of ≥ 100 mSv and determine their age distribution.

Methods: Data was retrieved retrospectively from established radiation dose monitoring systems by setting the threshold value of 100 mSv at four institutions covering 324 hospitals. The number of patients with CED ≥ 100 mSv only from recurrent CT exams during a feasible time period between 1 and 5 years was identified.

Effective Dose Assessment for Patients Undergoing Contemporary Fluoroscopically Guided Interventional Procedures.

The purpose of this study was to establish procedure-specific air kerma-area product (KAP) and effective dose for a large number of fluoroscopically guided interventional (FGI) procedures. This retrospective study collected dose data for consecutive adult cases from 12 examination rooms between May 2016 and October 2018. A total of 24,911 cases (50.

Data of CT bow tie filter profiles from three modern CT scanners.

As one of the key hardware components in Computed Tomography (CT) scanners, a bowtie filter reduces unnecessary radiation dose to the peripheries of a patient and equalizes radiation signal to the detector. Knowledge of the exact profiles from different bowtie filters are critical to model the imaging process of CT scanners and to estimate patient dose. However, bowtie filter profiles remain proprietary to most CT vendors.

Characterization of dynamic collimation mechanisms for helical CT scans with direct measurements.

Dynamic collimation is an important dose reduction mechanism for helical CT scans, especially for modern wide-beam scanner models. Its implementation and efficacy need to be studied to optimize CT scan protocols and to reduce unnecessary patient dose. The purpose of this study is to evaluate dynamic beam collimation for modern wide-beam CT scanners with direct measurements and to estimate the efficacy for dose reduction.

Exam-level dose monitoring in CT: Quality metric consideration for multiple series acquisitions.

Purpose: Multi-series CT examination is common in the clinic, but no metric is agreed upon to report the overall dose from such an examination. This work proposes a relevant metric for tracking patient dose from multi-series examinations and illustrates the evaluation method through explanatory examples.

Materials And Methods: In each acquisition series, a previously reported method was used to evaluate the cross-sectional average dose along the z-axis of a water phantom, with inputs of CTDI , scan length, tube current, and patient water-equivalent diameter.

Radiation Dose Monitoring for Fluoroscopically Guided Interventional Procedures: Effect on Patient Radiation Exposure.

Purpose To analyze the clinical effect of continuous dose monitoring and patient follow-up for fluoroscopically guided vascular interventional procedures over 8 years. Materials and Methods In this retrospective study, an in-house semiautomated system was developed for fluoroscopic dose monitoring. The quarterly number of procedures from January 2010 to December 2017 was analyzed with count time series to estimate quarterly change rate.