Effect of environmental factors on film badge dosimetry readings of dental office personnel.

Inadvertent exposure of film badges to environmental factors may produce fogging of the film and yield higher radiation exposure readings. Common environmental factors in everyday living were studied to assess their effect on film badge readings. Only heat appeared to have any significant effect, because moisture, chemicals, pressure, cold temperature, and non-work-related electromagnetic radiation did not substantially alter film badge readings. Therefore not all unexplained high readings on personnel film badge reports may be due to heat or other common environmental factors evaluated in this study.

Efficacy of radioiodine urinalysis.

Little exists in the literature to support the efficacy of urinalysis for demonstrating thyroid uptake of radioiodine. A review was made of a variety of kinetic models. Computer analysis and graphics were used to assess the variables in the two models chosen for this study. The applicability of each model was tested by using data obtained from a group of euthyroid subjects. The results indicate that using an integral urine-sampling method and a three-component model yields minimum detectable thyroid uptakes which fall well below required reporting limits. Furthermore, the results show that integral urine samples obtained in the first few hours post exposure may be used to predict major thyroid uptakes in time for effective thyroid blocking.

Suggested revisions in the radiology curriculum based on probable future trends.

Based on the trends noted in a recent survey of dental practitioners, the following areas in the predoctoral dental radiology curriculum should be emphasized: clinical use of rectangular cones; clinical use of E speed intraoral film; theory, maintenance, and use of automatic processors; theory and clinical use of panoramic machines; and opportunities to teach clinical techniques to others.

Dental radiologic survey of Virginia and Florida.

The results of a survey of 2,257 dental offices recording dental radiology practices are presented and compared to earlier surveys. In many practices patients were exposed to radiographs at predetermined intervals; the variables of manual processing are not well controlled, and darkrooms had excessive light.

A review of three incidents involving the release of 125I from seeds interstitially implanted within the prostate gland.

Three cases have occurred at the Medical College of Virginia in which 125I seeds were accidentally ruptured while being interstitially implanted within cancerous prostate-gland tumors. During the first incident the physician performing the surgery was contaminated. In the second and third cases, the iodine seeds were post-operatively discovered to be leaking. Both patients demonstrated significant thyroid uptakes and were administered potassium iodide as a blocking agent. Routine urine analyses and thyroid bioassays were performed during a period of several months to study the removal of 125I from the thyroid and to determine the effect potassium iodide had on the iodine-removal rate. Data obtained during the follow-up studies emphasize the necessity of post-operative monitoring and point out the value of administering a blocking agent in cases involving the release of 125I from a ruptured seed. The findings also indicate the risks during this type of therapeutic procedure may warrant the prophylactic use of exogenous iodine prior to implanting the iodine seeds.