PubMed HealthSearch

Biomedical subjects

H Q Woodard

Publications and source records attributed to H Q Woodard.

8 recordsLinked to original sources

Absorbed radiation dose in mammography.

Radiation dose from mammographic techniques was determined as a function of surface exposure, beam quality, and depth. Relative exposure vs. depth was measured in tissue-substitute materials by thermoluminescent dosimetry. The f-factors were calculated from elemental compositions of mastectomy specimens. Dose at depth depends on beam quality as well as exposure and tissue composition. Analysis of data from the ACS/NCI Screening Centers shows current average midbreast doses to be 25 times lower (film/screen) and 3 times lower (Xerox) than the 2 rads previously estimated. Quantitative risk indicators other than midbreast dose are also discussed.

Adipose Tissue

Radiation-induced soft-tissue and bone sarcoma.

From the records of Memorial Hospital of the past 50 years, 47 cases with an established diagnosis of radiation-induced sarcoma were identified and divided into two groups: the first included 20 cases of soft-tissue sarcoma arising from irradiated tissues, and the second comprised 27 cases of bone sarcoma arising from normal bones in the irradiated field. Medians for the latent periods from irradiation to diagnosis of bone and soft-tissue sarcoma were 11 and 12, years, respectively. In bone sarcomas, the latent period was longer after larger radiation doses and children appeared to be more susceptible to cancer induction than adults. Criteria for establishing the diagnosis of radiation-induced sarcoma and the magnitude of the risk of bone sarcoma are discussed.

Adolescent

Distribution and retention of 35S-sodium sulfate in man.

Measurements were made of the 35S content of tissues obtained from biopsies and autopsies made during and up to 6 months after treatment of chondrosarcoma or chordoma with carrier-free Na235SO4. Usually 70--90% of an intravenous dose was excreted in the urine during the first 3 days. The major component of the blood concentration had a biologic half-time of 0.4--0.7 days. The initial uptakes in chondrosarcoma, chordoma, and red bone marrow were high and nearly equal, but the rates of loss differed greatly. Uptake in epiphyseal cartilage was comparable to that in chondrosarcoma; uptake in other types of cartilage was lower, but subsequent loss was very slow. For an administered dose of 1 mCi per kilogram of body weight, the integrated radiation doses were 2.4 rads for blood, 33 rads for red bone marrow, 155 rads for chondrosarcoma, 49 rads for chordoma, and 135 rads for normal cartilage. Doses to muscle, skin, and fibrous tissue were 7--15 rads.

Adolescent