A new radiochromic dosimetry film was tested to determine its potential for patient skin dose monitoring in a fluoroscopically intensive environment such as the cardiac catheterization laboratory. The dose, time, energy, dose fractionation, dose rate, and sheet to sheet uniformity response were tested. All tests support the conclusion that this is a simple, noninvasive, retrospective method to identify skin regions at risk from high x-ray doses. The consistency and accuracy of dose measurements allow for an estimation of the localized skin dose to those patients who are susceptible to radiation induced skin injury.

A 90 degrees-tau 1-90 degrees-tau 2-image acquisition pulse sequence allows spatial mapping of resonant frequency. This sort of sequence has previously been used for magnet shimming, and its use in chemical-shift imaging has been proposed. The authors used this sequence in magnetic resonance imaging of a phantom to demonstrate the magnetic field gradients arising from susceptibility differences within the phantom and allow those gradients to be measured. Gradients may arise near interfaces between substances that cannot support the same magnetic flux density. The pulse sequence was found to work well in lower-field-strength instruments.

Traditionally, the absorption properties of protective aprons used in diagnostic radiology have been specified in units of lead equivalent thickness. This is appropriate and accurate when lead is the only high-atomic-numbered component in the apron. In an attempt to manufacture light-weight protective apparel, however, some manufacturers have included other elements with k absorption edges in the energy range of interest, to provide equivalent absorption properties with less weight. With these other high-atomic-numbered elements added, the lead equivalence of the apparel becomes a function of the photon energy. This must be recognized and specified by the supplier, because lead apparel is used in environments other than diagnostic radiology, where the shielding benefits may be substantially less than expected when specifications are based on the diagnostic x-ray energy range.

No abstract

No abstract