Dose Indices of Radiation to Skin in Fluoroscopically Guided Invasive Cardiology Procedures

Abstract

Tissue injury depends on the extent as well as the intensity of the assault. It would be helpful to develop skin dose indices that are more descriptive of the skin area receiving radiation above a threshold value of potential injury. For monitoring radiation exposure to patients, radiochromic film was placed close to the skin of a patient undergoing cardiac catheterization procedures. With the approval of the Institutional Review Board, films from 36 patients were scanned. Contours were drawn at the increment of 100 cGy in air kerma. Using each contour value as a threshold, the area exceeding this threshold and the average dose within this area were computed. For the four patients who had skin doses exceeding the 200 cGy threshold, the peak entrance doses have a range from 230 cGy to 409 cGy. However, these high radiation exposures were confined to limited skin areas and support the absence of any significant skin injury in these patients. The area exceeding a chosen threshold value and the average dose within the area circumscribed might therefore serve as helpful measures of the assault to the skin. This investigation has demonstrated the technical feasibility of providing such dose indices.

Calibration of GafChromic XR‐RV3 radiochromic film for skin dose measurement using standardized x‐ray spectra and a commercial flatbed scanner

“…7 These methods include the use of thermoluminescent dosimeters ͑TLDs͒, radiochromic film, metal-oxide semiconductor field-effect transistors ͑MOS-FETs͒, ionization chambers, and software-based dose calculators. [8][9][10][11][12][13][14][15][16][17][18] MOSFETs and TLDs can be time-consuming to attach to a patient's back and, unless there is a priori knowledge of the expected x-ray field locations, often produce an insufficient sampling density to capture the spatial features and peak dose from multiple overlapping x-ray exposures. 9,10 Radiochromic film offers high spatial resolution, large surface area ͑e.g., 14 in.…”