Evaluation of skin dose calculation factors in interventional fluoroscopy.

Purpose: The purpose of this study was to measure fluoroscopic dose calculation factors for modern fluoroscopy-guided interventional (FGI) systems, and to fit to analytical functions for peak skin dose (PSD) calculation.

Methods: Table transmission factor (TTF), backscatter factor (BSF), and a newly termed kerma correction factor (KCF) were measured for two interventional fluoroscopy systems. For each setup, air kerma rates were measured using a small ionization chamber in fluoroscopic service mode while selecting kVp, copper (Cu) filter thickness, incident angle, and x-ray field size at the assumed patient skin locations.

Procedure-specific CT Dose and Utilization Factors for CT-guided Interventional Procedures.

Purpose To present procedure-specific radiation dose metric distributions and define quantitative CT utilization factors for CT-guided interventional procedures. Materials and Methods This single-center, retrospective study collected dictation reports and radiation dose data from 9143 consecutive CT-guided interventional procedures in adult patients from 2012 to 2017. Procedures were sorted into four major interventional categories: ablation, aspiration, biopsy, and drainage, each of which was further divided into subcategories.

Comprehensive evaluation of broad-beam transmission of patient supports from three fluoroscopy-guided interventional systems.

Purpose: The purpose of the study was to measure, evaluate, and model the broad-beam x-ray transmission of the patient supports from representative modern fluoroscopy-guided interventional systems, for patient skin dose calculation.

Methods: Broad-beam transmission was evaluated by varying incident angle, kVp, added copper (Cu) filter, and x-ray field size for three fluoroscopy systems: General Electric (GE) Innova 4100 with Omega V table and pad, Siemens Axiom Artis with Siemens tabletop "narrow" (CARD) table and pad, and Siemens Zeego with Trumpf TruSystem 7500 table and pad. Field size was measured on the table using a lead ruler for all setups in this study.

Assessment of radiation dose from abdominal quantitative CT with short scan length.

Objective: To assess radiation dose for patients who received abdominal quantitative CT and to compare the midpoint dose [D(0)] at the centre of a 1-cm scan length with the volume CT dose index (CTDI). Although the size-specific dose estimate (SSDE) proposed in The American Association of Physicists in Medicine Report No. 204 is not applicable for short-length scans, commercial dose-monitoring software, such as Radimetrics Enterprise Platform (Bayer HealthCare, Whippany, NJ), reports SSDE for all scans.

Comparison of computed tomography shielding design methods using RadShield.

Purpose: To comprehensively compare four computed tomography (CT) scanner shielding design methods using RadShield, a Java-based graphical user interface (GUI).

Methods: RadShield, a floor plan based GUI, was extended to calculate air kerma and barrier thickness using accepted methods from the National Council on Radiation Protection and Measurements (NCRP), the British Institute of Radiology, and a method using isodose maps, for spatially distributed points beyond user defined barriers. For a stationary CT scanner, the overall shielding recommendations found using RadShield were also compared to those found by American Board of Radiology certified diagnostic medical physicists using the conventional NCRP dose length product method and the isodose map method.

RadShield: semiautomated shielding design using a floor plan driven graphical user interface.

The purpose of this study was to introduce and describe the development of RadShield, a Java-based graphical user interface (GUI), which provides a base design that uniquely performs thorough, spatially distributed calculations at many points and reports the maximum air-kerma rate and barrier thickness for each barrier pursuant to NCRP Report 147 methodology. Semiautomated shielding design calculations are validated by two approaches: a geometry-based approach and a manual approach. A series of geometry-based equations were derived giv-ing the maximum air-kerma rate magnitude and location through a first derivative root finding approach.