Radiation dose in x-ray computed tomography (CT) has become a topic of high interest due to the increasing numbers of CT examinations performed worldwide. This review aims to present an overview of current concepts for both scanner output metrics and for patient dosimetry and will comment on their strengths and weaknesses. Controversial issues such as the appropriateness of the CT dose index (C...

Intensity modulated radiation therapy (IMRT) treatment planning typically considers beam optimization and beam delivery as separate tasks. Following optimization, a multi-leaf collimator (MLC) or other beam delivery device is used to generate fluence patterns for patient treatment delivery. Due to limitations and characteristics of the MLC, the deliverable intensity distributions often differ f...

The purpose of this study is to investigate the effectiveness of the HIPO planning and optimization algorithm for real-time prostate HDR brachytherapy. This study consists of 20 patients who underwent ultrasound-based real-time HDR brachytherapy of the prostate using the treatment planning system called Oncentra Prostate (SWIFT version 3.0). The treatment plans for all patients were optimized u...

OBJECTIVE The Image Gently Campaign of The Alliance for Radiation Safety in Pediatric Imaging seeks to increase awareness of opportunities to lower radiation dose in the imaging of children. Pause and Pulse is the most recent phase of the campaign, addressing methods of dose optimization in pediatric fluoroscopy. CONCLUSION This article discusses 10 steps that can be taken for fluoroscopic do...

Background Increasing the x-ray film to focus distance (FFD), has been recommended as a practical dose optimization tool for patients undergoing conventional radiological procedures. In the previous study, we demonstrated a 32% reduction in absorbed dose is achievable due to increasing the FFD from 100 to 130 cm during pediatric chest radiography. The aim of this study was to examine whether in...

Introduction: Skin dose and depth dose distribution of some beta sources that can contaminate skin or protective clothing covering the skin have been calculated using VARSKIN2. Materials and Methods: In this research, absorbed dose to skin and depth dose from the skin surface have been calculated for 90Sr/90Y, 147Pm, 32P beta emitter radioisotopes by using input parameters: activity of source, ...

Introduction: Due to the use of ionizing radiation in the CT scan, optimal parameters should be used to reduce the risk of cancer in patients who are constantly exposed to X-rays. The aim of this study was to optimize the parameters used in CT scan of cervical vertebrae and neck soft tissue with minimal loss of image quality   Materials and Methods: In this s...

Introduction: Beam-angle optimization (BAO) is a computationally intensive problem for a number of reasons. First, the search space of the solutions is huge, requiring enumeration of all possible beam orientation combinations. For example, when choosing 4 angles out of 36 candidate beam angles, C36 = 58905 possible combinations exist.  Second, any change in a   beam 4 config...