USDOE Human Subjects Research Database, fiscal year 1995

Brookhaven National Laboratory

Project Identifier: BNL-95-263

Project Title:

Medical Imaging with Xenon K-Edge Dichromography

Principle Investigator: Dr. William Thomlinson

Project started in: 1995

Fiscal Year 1995 Funding for Research on Human Subjects:

Project Funding Information:
Project received funding in Fiscal Year 1995.
Project used human subjects in Fiscal Year 1995.

Funding Sources:

DOE: Office of Health and Environmental Research (OHER)

Amount: $12,000 (Est.)

Information on Use of Human Subjects:

Project does not involve use of multiple protocols/subprojects.

IRB Review:
Type of Review: Full Board
Most Recent Approval: July 12, 1995

Number of Human Subjects in the Last Reporting Period for this Project: 2
(Reporting periods vary.)

Type of Human Subjects Involvement:

Ionizing Radiation and Radioactive Substances:

External use of ionizing radiation on human subjects.

• For diagnostic research.

Chemical Substances:

Internal use of chemical substances (solid, liquid, or gas) in human subjects.

• For diagnostic research.

Instrument/Device/Product Testing or Man-Machine Studies:

Use of human subjects to develop/test instruments, materials, devices, or objects.

(a. Objectives, b. Methodology, c. Ionizing Radiation, Radioactive Substances, or Chemical Substances to which human subjects are exposed, d. Involvement of Human Subjects [d.1. procedures used, d.2. risks if any])

Lung cancer remains the leading cause of cancer-related death in the US for both men and women. This grim statistic reflects the inadequate diagnostic tests available for early detection of the disease. In another Brookhaven project, the Coronary Angiography project (BNL-86-210), we have demonstrated the feasibility of using monochromatic synchrotron x-rays and iodine k-edge dichromography to image vascular structures in humans. This study is a new application of k-edge dichromography, using inhaled xenon as the contrast agent in order to image the proximal bronchial passages in human subjects. Subjects will inspire a small amount of non-radioactive xenon into their air passages. The subjects will be seated on a moveable chair which will pass through two monochromatic x-ray beams which bracket the k-edge of xenon. The images resulting from subtraction of the low from the high energy image will contain only xenon-filled structures, in this case, the bronchial passages. The k-edge of xenon is 34.56 kiloelectronvolts (keV), which is very similar to the k-edge of iodine, 33.17 keV. Thus, only minor adjustments of the monochromator are necessary to perform the studies. The plan is to study approximately 25 patients during the first year. Based on our findings, we may elect to perform repeat examinations, particularly in patients who are at increased risk to develop lung cancer. A potential side effect of radiation is the induction of cancer. However, no harm in a human individual or in a large population exposed at doses as low as those delivered in this procedure has been reported. The estimation of risk of harm can be obtained only by extrapolation from much higher doses. Xenon is an inert gas; when it is inhaled in very small quantities and mixed with 20% oxygen, there is essentially no known risk from inhaling the xenon gas.