This report describes a comparison of cassette front material in terms of its effect on radiographic imaging. We compared aluminum, carbon fiber, and a new material (Hylite) in terms of their absorption, scatter rate (lead-disc method), MTF, and subjective appearance, using an extremity phantom. For scatter rate and MTF, we also carried out analysis using Monte Carlo simulation. Results indicated that the cassette using the new material was intermediate between the aluminum panel and CFRP panel in terms of weight, absorption rate, and scatter rate. We also found that the new panel material showed a visual difference from the aluminum panel when a lower tube voltage and thinner object were assigned.
We evaluated the effect of fat suppression techniques (fatsat) and magnetization transfer contrast (MTC) for MR venography (MRV) using the 2D TOF sequence in the lower extrmities. In addition, the improvement of vessel conspicuity resulting from three different warming procedures was evaluated. Three combinations of fatsat and MTC were performed. Both the signal intensity ratio (SIR) and contrast-to-noise ratio (CNR) were measured at ROIs of vein, fat, and muscle in knee. The vessel conspicuity of MIP was evaluated by three radiologists. The experimental results indicated that MTC pulses did not affect fatsat. The combination techniques of fatsat and MTC improved SIR (≒13%) and CNR (≒5%) of the vein compared with techniques using fatsat only. The continuous warming procedure was better than temporary warming in terms of vessel conspicuity. We conclude that the combined techniques of fatsat and MTC with the continuous warming procedure were clearly useful for MRV using the 2D TOF sequence in the lower extremities.