ABSTRACT
PURPOSE: The aim of this study was to investigate the efficacy of different designs and types of ocular radiation protection devices depending on simulated varied body heights in a phantom-simulated thoracic intervention. MATERIALS AND METHODS: A clinical angiography system with a standardized fluoroscopy protocol with an anthropomorphic chest phantom as a scattering object and optically stimulated luminescence dosimeters for measuring radiation dose were used. The dosimeters were placed at the position of eyes of an anthropomorphic head phantom simulating the examiner. The head phantom was placed on a height-adjustable stand simulating the height of the examiner from 160 to 200 cm with 10 cm increments. The dose values were then measured with no radiation protection, a weightless-like radiation protection garment, radiation protection glasses and visors. RESULTS: The average dose reduction using radiation protection devices varied between 57.7 and 83.4% (p < 0.05) in comparison with no radiation protection. Some radiation protection glasses and visors showed a significant dose reduction for the eye lenses when the height of the examiner increased. The right eye was partially less protected, especially if the distances between the simulated examiner's head and the scatter object were small. CONCLUSION: All the investigated protection devices showed a significant reduction in radiation exposure to the simulated examiner. For some devices, the radiation dose increased with decreasing distance to the scattering object, especially for the right eye lens.
Subject(s)
Eye Protective Devices , Phantoms, Imaging , Radiation Exposure/prevention & control , Radiation Protection/methods , Equipment Design , Radiation DosageABSTRACT
There are no guidelines for the use of heparin in the prophylaxis of deep vein thrombosis in outpatients. In a prospective clinical investigation in 1996 and 1997, 1321 outpatients after trauma of the lower extremities were screened by duplex-color-coded-ultrasound in order to detect deep vein thrombosis. There were two separate groups: group A with drug prophylaxis of deep vein thrombosis (n = 723) and group B (n = 598) without. The classification A or B was mainly related to the ability of weight bearing (at least 20 kp) and of ankle mobility (at least 20 degrees). Patients who did not achieve both criteria were classified in group A and were treated with heparin until they attained a higher level of activity (B). Group A showed 30 deep vein thrombosis while group B had no thromboembolic complications. We conclude that outpatients achieving a level of activity close to a physiological situation will show no thromboembolic complications.
