4 Clinical Trials for Various Conditions
The primary objective of the present trial is to compare the radiation attenuation provided by XPF caps (0.5mm lead-equivalent and 0.3mm lead-equivalent) to the standard protection (fabric cap, basically no protection) as measured in % radiation attenuation) during 150 days of fluoroscopy guided cardiology interventions. The second objective is to compare the operator comfort (rated on a visual analog scale) of wearing the XPF protection caps compared to the standard fabric caps.
The PREFER II trial primary objective of the trial is to show how much radiation attenuation is provided by XPF thyroid collars in absolute and relative terms.
Ionizing radiation efficiently induces chromosomal aberrations (CA) and several studies of CA have now been conducted among small groups of flight crews. However, most of the studies only evaluated the unstable aberrations that reflect recent exposures, but not long-term cumulative cosmic radiation exposure. Chromosome painting by fluorescence in situ hybridization (FISH) is a widely used and established cytogenetic method for detecting stable aberrations such as translocations. Thus, FISH can be used for estimating chromosomal damage from cumulative radiation exposure. No large studies of flight crews utilizing FISH have been conducted to date. We propose a study to measure CA using FISH in a group of pilots estimated to have high comic radiation exposure based on flight histories, i.e., those with long duration flying international routes, and a comparison group of university faculty with minimal flying history. These measurements will be used to determine if pilots have elevated frequencies of CA (specifically stable translocations) as compared with the university faculty. In addition, the frequencies of CA will be examined in relation to the cumulative cosmic radiation dose to determine if there is a dose-response relationship. Individual cumulative doses will be calculated from pilot flight histories using a computer program developed by the FAA which estimates cosmic radiation does by accounting for changes in altitude and latitude, and the 11-year solar cycle at the time of the flight. We will collect information on age, lifestyle factors, diet, health history, family cancer history, and medical radiation exposures from personal interview and self-administered dietary questionaire. These factors may affect the CA frequency and so we plan to adjust for them in the statistical analyses. Pilots will be identified based on the Allied Pilots Association roster and faculty from a commercial company that maintains a database of university faculty, including those in the Chicago area. Potential participants will be notified of the study by mail and recruited/screened for eligibility over the telephone. We will compensate participants $100 for their time. A field station will be set up at a medical or health clinic convenient to the participants, where interviews Will be conducted and a peripheral blood sample collected. Participants will be notified of the overall study results and may request their personal CA results at the end of the study. Participants may also choose to have additional blood drawn, however this blood sample will be anonymized so that it cannot be linked back to the participant. Genotypic variants in DNA repair (and possibly other) genes will be evaluated for an effect on CA frequency.
Radiation exposure to operator is an occupational hazard of invasive cardiologists. During radial access for diagnostic catheterization, a new radio-dense arm board is advertised to reduce operator radiation exposure. The investigators randomize patients to a new radio-dense armboard versus a standard radio-transparent armboard during diagnostic catheterization and measure radiation exposure to the operator. Both groups have a radio-dense pelvic shield in place. The investigators hypothesize that operator radiation dose will be decreased by use of the radio-dense armboard.