Development of a neonate X-ray phantom for 2D imaging applications using single-tone inkjet printing.

Purpose: Inkjet printers can be used to fabricate anthropomorphic phantoms by the use of iodine-doped ink. However, challenges persist in implementing this technique. The calibration from grayscale to ink density is complex and time-consuming.

Physics-based iterative reconstruction for dual-source and flying focal spot computed tomography.

Purpose: For single-source helical Computed Tomography (CT), both Filtered-Back Projection (FBP) and statistical iterative reconstruction have been investigated. However, for dual-source CT with flying focal spot (DS-FFS CT), a statistical iterative reconstruction that accurately models the scanner geometry and acquisition physics remains unknown to researchers. Therefore, our purpose is to present a novel physics-based iterative reconstruction method for DS-FFS CT and assess its image quality.

Flat Panel Detector c-Arms Are Associated with Dramatically Reduced Radiation Exposure During Ureteroscopy and Produce Superior Images.

We wished to determine whether newly available flat panel detector (FPD) c-arms were (1) associated with lower radiation dose during ureteroscopy (URS) than conventional image intensifier (CII) c-arms and (2) to compare fluoroscopic image quality between the units. We retrospectively reviewed 44 consecutive patients undergoing URS at a pediatric hospital, with c-arms assigned by availability in the operating room. We performed dosimetry experiments using the same c-arms on standard phantoms.

Development of a novel framework to evaluate the localization accuracy of tomosynthesis-guided breast biopsy units.

Purpose: To develop a scheme to quantitatively assess localization accuracy of tomosynthesis-guided vacuum-assisted breast biopsy apparatus.

Methods: A phantom containing a metallic pellet on a flexible plastic shaft was constructed and was tested in cranio-caudal (CC) and lateral (LAT) arm biopsy geometries following the standard clinical breast biopsy workflow. Three points were manually digitized on tomosynthesis images including: the center of the target, and the tip of the needle in pre- and postfire positions.

Improving Low-Dose Pediatric Abdominal CT by Using Convolutional Neural Networks.

Purpose: To evaluate the efficacy of convolutional neural networks (CNNs) to improve the image quality of low-dose pediatric abdominal CT images.

Materials And Methods: Images from 11 pediatric abdominal CT examinations acquired between June and July 2018 were reconstructed with filtered back projection (FBP) and an iterative reconstruction (IR) algorithm. A residual CNN was trained using the FBP image as the input and the difference between FBP and IR as the target such that the network was able to predict the residual image and simulate the IR.

Intraoperative Use of O-arm in Pediatric Cervical Spine Surgery.

Introduction: Traditionally, fluoroscopy and postoperative computed tomographic (CT) scans are used to evaluate screw position after pediatric cervical spine fusion. However, noncontained screws detected postoperatively can require revision surgery. Intraoperative O-arm is a 3-dimensional CT imaging technique, which allows intraoperative evaluation of screw position and potentially avoids reoperations because of implant malposition.

The effect of surgeon versus technologist control of fluoroscopy on radiation exposure during pediatric ureteroscopy: A randomized trial.

Background: Fluoroscopy is commonly used during pediatric ureteroscopy (PURS) for urolithiasis, and the most important contributor to overall radiation exposure is fluoroscopy time (FT). One factor that may impact FT is who controls activation of the fluoroscope: the urologist (with a foot pedal) or the radiation technologist (as directed by the urologist). While there are plausible reasons to believe that either approach may lead to reduced FT, there are no systematic investigations of this question.

Current state of practice regarding digital radiography exposure indicators and deviation indices: Report of AAPM Imaging Physics Committee Task Group 232.

Beginning with the advent of digital radiography systems in 1981, manufacturers of these systems provided indicators of detector exposure. These indicators were manufacturer-specific, and users in facilities with equipment from multiple manufacturers found it a challenge to monitor and manage variations in indicated exposure in routine clinical use. In 2008, a common definition of exposure index (EI) was realized in International Electrotechnical Commission (IEC) International Standard 62494-1 Ed.

Correction to: Ionizing radiation from computed tomography versus anesthesia for magnetic resonance imaging in infants and children: patient safety considerations.

The published version of this article incorrectly lists Dr. Joseph P. Cravero in the Department of Radiology at Boston Children's Hospital.

Ionizing radiation from computed tomography versus anesthesia for magnetic resonance imaging in infants and children: patient safety considerations.

In the context of health care, risk assessment is the identification, evaluation and estimation of risk related to a particular clinical situation or intervention compared to accepted medical practice standards. The goal of risk assessment is to determine an acceptable level of risk for a given clinical treatment or intervention in association with the provided clinical circumstances for a patient or group of patients. In spite of the inherent challenges related to risk assessment in pediatric cross-sectional imaging, the potential risks of ionizing radiation and sedation/anesthesia in the pediatric population are thought to be quite small.

How we read pediatric PET/CT: indications and strategies for image acquisition, interpretation and reporting.

PET/CT plays an important role in the diagnosis, staging and management of many pediatric malignancies. The techniques for performing PET/CT examinations in children have evolved, with increasing attention focused on reducing patient exposure to ionizing radiation dose whenever possible and minimizing scan duration and sedation times, with a goal toward optimizing the overall patient experience. This review outlines our approach to performing PET/CT, including a discussion of the indications for a PET/CT exam, approaches for optimizing the exam protocol, and a review of different approaches for acquiring the CT portion of the PET/CT exam.

Development of a tool to aid the radiologic technologist using augmented reality and computer vision.

This technical innovation describes the development of a novel device to aid technologists in reducing exposure variation and repeat imaging in computed and digital radiography. The device consists of a color video and depth camera in combination with proprietary software and user interface. A monitor in the x-ray control room displays the position of the patient in real time with respect to automatic exposure control chambers and image receptor area.

Operational and Dosimetric Aspects of Pediatric PET/CT.

No consistent guidelines exist for the acquisition of a CT scan as part of pediatric PET/CT. Given that children may be more vulnerable to the effects of ionizing radiation, it is necessary to develop methods that provide diagnostic-quality imaging when needed, in the shortest time and with the lowest patient radiation exposure. This article describes the basics of CT dosimetry and PET/CT acquisition in children.

Quality of pediatric abdominal CT scans performed at a dedicated children's hospital and its referring institutions: a multifactorial evaluation.

Background: Pediatric patients requiring transfer to a dedicated children's hospital from an outside institution may undergo CT imaging as part of their evaluation. Whether this imaging is performed prior to or after transfer has been shown to impact the radiation dose imparted to the patient. Other quality variables could also be affected by the pediatric experience and expertise of the scanning institution.

Neuroimaging of Children With Surgically Treated Hydrocephalus: A Practical Approach.

Objective: Children with surgically treated hydrocephalus commonly undergo multiple neuroimaging studies. The purpose of this article is to share an experience with use of the as low as reasonably achievable (ALARA) principle to guide the imaging approach to these patients.

Conclusion: A reasonably achievable strategy for minimizing ionizing radiation in patients with surgically treated hydrocephalus includes rapid-sequence MRI and judicious use of dose-optimized head CT.

Selecting appropriate gastroenteric contrast media for diagnostic fluoroscopic imaging in infants and children: a practical approach.

In our experience, questions about the appropriate use of enteric contrast media for pediatric fluoroscopic studies are common. The purpose of this article is to provide a comprehensive review of enteric contrast media used for pediatric fluoroscopy, highlighting the routine use of these media at a large tertiary care pediatric teaching hospital.

Pediatric thoracic CT angiography at 70 kV: a phantom study to investigate the effects on image quality and radiation dose.

Background: Studies have demonstrated that 70-kilovolt (kV) imaging enhances the contrast of iodine, potentially affording a reduction in radiation dose while maintaining the contrast-to-noise ratio (CNR). There is a maximum amount of image noise beyond which increased contrast does not improve structure visualization. Thus, noise should be constrained during protocol optimization.

Sinus Computed Tomography Imaging in Pediatric Cystic Fibrosis: Added Value?

Study Objective: To evaluate the prevalence of computed tomography (CT) sinus imaging in a pediatric cystic fibrosis (CF) population, determine changes in Lund Mackay (LM) scores over time, and estimate radiation exposure.

Study Design: Case series with chart review.

Setting: Tertiary care children's hospital.

Size-based protocol optimization using automatic tube current modulation and automatic kV selection in computed tomography.

Size-based diagnostic reference ranges (DRRs) for contrast-enhanced pediatric abdominal computed tomography (CT) have been published in order to establish practical upper and lower limits of CTDI, DLP, and SSDE. Based on these DRRs, guidelines for establishing size-based SSDE target levels from the SSDE of a standard adult by applying a linear correction factor have been published and provide a great reference for dose optimization initiatives. The necessary step of designing manufacturer-specific CT protocols to achieve established SSDE targets is the responsibility of the Qualified Medical Physicist.

AAPM/SNMMI Joint Task Force: report on the current state of nuclear medicine physics training.

The American Association of Physicists in Medicine (AAPM) and the Society of Nuclear Medicine and Molecular Imaging (SNMMI) recognized the need for a review of the current state of nuclear  medicine physics training and the need to explore pathways for improving nuclear medicine physics training opportunities. For these reasons, the two organizations formed a joint AAPM/SNMMI Ad Hoc Task Force on Nuclear Medicine Physics  Training. The mission of this task force was to assemble a representative group of stakeholders to:• Estimate the demand for board-certified nuclear medicine physicists in the next 5-10 years,• Identify the critical issues related to supplying an adequate number of physicists who have received the appropriate level of training in nuclear medicine physics, and• Identify approaches that may be considered to facilitate the training of nuclear medicine physicists.

Pediatric CT dose reduction for suspected appendicitis: a practice quality improvement project using artificial gaussian noise--part 2, clinical outcomes.

OBJECTIVE. The purpose of this study was to determine the effect of a nominal 50% reduction in median absorbed radiation dose on sensitivity, specificity, and negative appendectomy rate of CT for acute appendicitis in children. MATERIALS AND METHODS.

Managing radiation dose from thoracic multidetector computed tomography in pediatric patients: background, current issues, and recommendations.

This review includes an overview of the fundamental physics and dose metrics of multidetector computed tomography (MDCT), a brief summary of research concerning health effects of ionizing radiation with an emphasis on risks to children, research of dose optimization, and practical recommendations that can be implemented immediately at the radiologist's own center. It is hoped that by combining results of recent research, this review will provide valuable information for the practicing radiologist. The sections of this review were designed such that each section can be read independently or skipped depending on the level of expertise of the reader.

The optimal optical readout for the x-ray light valve--document scanners.

The x-ray light valve (XLV) is a novel, potentially low-cost, x-ray detector that converts an x-ray exposure into an optical image stored in a liquid crystal cell. This optical image is then transferred from the liquid crystal cell to a computer through an optical-to-digital imaging readout system. Previously, CCD-based cameras were used for the optical readout, but recently it was proposed that an inexpensive optical scanner, such as an office document scanner, is a better match to the optical properties of the XLV.

The x-ray light valve: a low-cost, digital radiographic imaging system--spatial resolution.

An x-ray light valve (XLV) coupled with an optical scanner has the potential to meet the need for a low-cost, high quality digital imaging system for general radiography. The XLV/scanner concept combines three well-established, and hence, low-cost technologies: An amorphous selenium (a-Se) layer as an x-ray-to-charge transducer, a liquid crystal (LC) cell as an analog display, and an optical scanner for image digitization. The XLV consists of an a-Se layer and LC cell in a sandwich structure which produces an optical image in the LC layer upon x-ray exposure.