Radiation dose reduction using novel size 1 and size 0 rectangular collimators in pediatric dental imaging.

Objectives: Commercial intraoral rectangular collimators are available for collimating to size 2 image receptor. The benefits of reducing the x-ray beam to match the area of the image detector in adult intraoral radiography are endorsed internationally. However, in pediatric dentistry the image receptor can be further decreased to size 1 and 0.

Assessment of dental radiation dose reduction utilizing mathematical pediatric phantom models: applications in clinical practice.

Objectives: Replacing conventional round intraoral collimators with rectangular collimators provides a considerable radiation dose reduction in adult patients. This study aimed to determine the radiation dose reduction via mathematical phantom when converting from round to appropriately sized rectangular collimation in children ages 5 to 15 years.

Method And Materials: Virtual full mouth series (FMX) were simulated using a commercially available radiation dose software.

Kerma area product (KAP) and scatter measurements for intraoral X-ray machines using three different types of round collimation compared with rectangular beam limiter.

Objectives:: The objective of the study was to determine the radiation dose reduction achieved when rectangular collimation was used on various round collimators. In addition, we evaluated the tissue doses imparted to various head and neck organs.

Methods:: To evaluate the variation in radiation output based on the variable geometric configurations, the kerma area product (KAP) was measured using a commercially available KAP-meter with an internal ion chamber capable of detecting both radiation dose (µGy) and the primary X-ray beam area.

METHOD FOR OCCUPATIONAL SKIN DOSE ESTIMATION IN UPPER EXTREMITY 131I-MIBG CONTAMINATION.

This study examines upper extremity skin contamination of nuclear medicine and radiation safety staff during 131I-Metaiodobenzylguanidine (MIBG) therapy. Utilizing retrospective data, a methodology for performing a rapid assessment of the radiation dose to the skin of the upper extremities is presented. Using the skin contamination measurements and calculated skin dose for each contamination incident at our facility, a conversion factor (XE) was derived that estimates skin dose (DE) based on the initial contamination measurement.

Investigation of dental cone-beam CT pixel data and a modified method for conversion to Hounsfield unit (HU).

Objectives: To investigate the relationship in dental cone-beam CT (CBCT) between the manufacturer-reported image pixel data and a modified conversion to CT number densities in Hounsfield unit (HU).

Methods: A standardized CT phantom was imaged using typical clinical parameters on CBCT from three manufacturers (Carestream 9300, Carestream Health, Rochester, NY; J Morita 3D Accutomo, J. Morita Mfg.

Female gonadal shielding with automatic exposure control increases radiation risks.

Background: Gonadal shielding remains common, but current estimates of gonadal radiation risk are lower than estimated risks to colon and stomach. A female gonadal shield may attenuate active automatic exposure control (AEC) sensors, resulting in increased dose to colon and stomach as well as to ovaries outside the shielded area.

Objective: We assess changes in dose-area product (DAP) and absorbed organ dose when female gonadal shielding is used with AEC for pelvis radiography.

Intussusception reduction: Effect of air vs. liquid enema on radiation dose.

Background: Both air and radiopaque liquid contrast are used to reduce ileocolic intussusception under fluoroscopy. Some suggest air lowers radiation dose due to shorter procedure times. However, air enema likely lowers radiation dose regardless of fluoroscopy time due to less density over the automatic exposure control cells.

THE EFFECT OF RADIATION SHIELDS ON OPERATOR EXPOSURE DURING CONGENITAL CARDIAC CATHETERISATION.

Cardiac catheterisation personnel are exposed to occupational radiation and its health risks. Little data exist regarding the efficacy of radiation-protective equipment from congenital catheterisation laboratories (CLs). The authors retrospectively reviewed data in which CL operators wore a radiation dosemeter during catheterizations on patients of >20 kg.

Developing low-dose C-arm CT imaging for temporomandibular joint (TMJ) disorder in interventional radiology.

Background: Manufacturers have provided C-arm CT imaging technologies for applications in interventional radiology in recent years. However, clinical imaging protocols and radiation doses have not been well studied or reported.

Objective: The purpose of this study is to develop low-dose settings for clinically acceptable CT imaging of temporomandibular joint in interventional radiology suites, using a C-arm imaging angiography system.

Medical radiation exposure and risk of retinoblastoma resulting from new germline RB1 mutation.

Although ionizing radiation induces germline mutations in animals, human studies of radiation-exposed populations have not detected an effect. We conducted a case-control study of sporadic bilateral retinoblastoma, which results from a new germline RB1 mutation, to investigate gonadal radiation exposure of parents from medical sources before their child's conception. Parents of 206 cases from nine North American institutions and 269 controls participated; fathers of 184 cases and 223 friend and relative controls and mothers of 204 cases and 260 controls provided information in telephone interviews on their medical radiation exposure.

Dose reduction fluoroscopy in pediatrics.

Background: It is essential that we find ways to reduce radiation exposure to children and maintain image quality.

Objectives: We compared radiation dose, image quality, and spatial resolution when continuous and pulse fluoroscopy with a full and half dose are applied to a phantom. The film-screen technique was compared to fluoroscopy with the digitized spot technique (fluoro grab image) in procedures such as voiding cystourethrogram (VCUG).