Intramedullary Dose Measurements in the Beagle Following Whole-Body 1000-kVp X-Irradiation

Holes of sufficient size to admit small dosimeters were drilled into several loci within the major bones of an embalmed beagle cadaver. The dosimeters consisted of 5.5 mg of LiF dosimetry powder sealed within polyethylene tubing. The animal was whole-body bilaterally irradiated with 1000-kVp X-rays; the results are given in units of rads per 100 R of midline air exposure. The average of the measurements made throughout the ribs was 76.6 rads, while throughout the other bones with thicker walls (and with smaller associated scattering masses) the doses ranged from 66.8 to 71.8 rads. If ionizing radiation acts directly on the hematopoietic centers in bone marrow, then an irradiation of this type would result in a more pronounced effect on this function in the ribs than in the marrow of the thicker bones.