ABSTRACT
Objective To study the radiation dose distribution in the X-ray room,and provide the strategy of radiation protection for the medical staff and the patient’s nursing who had to enter the room while the X-ray was exposing.Methods The thermolumi-nescent dosemeters(TLDs)was placed around the center of the X-ray tube with the same level of the bed.Then,exposure parame-ters,including the X-ray tube voltage value and the field of view,were changed for different groups while exposing.All of the TLDs were taken back to the lab for analysis.Results The differences between the two groups which had the same distance in different di-rections were statistically significant (P <0.01).With the same radiographic condition and direction,the radiation dose on the site of 10 cm from X-ray tube center was the maximum,while the site of 120 cm was the minimum.With the same radiographic condition and distance,the radiation dose on the anode side of the X-ray tube in the room was relative lower,while the site behind the X-ray tube was relative higher.With the same voltage value,distance and direction,the same sites that had the smaller FOV(34 cm×34 cm) received lower radiation dose than those with larger FOV(52.6 cm× 52.6 cm).Meanwhile,the sites with the voltage of 70 kV re-ceived the lower radiation dose than that with the voltage value of 120 kV.Conclusion In the X-ray room,the medical staff and the patient’s nursing can choose the area on the right side(anode side),keep far away from the X-ray tube center,avoid the rear of the X-ray tube and the cathodic direction of the X-ray tube to reduce the radiation dose.
ABSTRACT
Objective To investigate MRI signal features and MRI appearances of patients with advanced stage in polyacrylamide hydrophilic gel injection for facial plasty.Methods In this study,MRI of 11 cases with 23 polyacrylamide hydrophilic gel injection of facial plasty for 6 to 10 years were retrospectively reviewed.All images were acquired with GE 3.0T MR imaging unit.MR sequences,including FSE T1WI,FSE FS T2WI,and STIR were applied with 8-channel brain coil.MRIs sliced through the maxillofacial region in the transverse,coronal and sagittal planes.Results In 11 cases of 23 polyacrylamide hydrophilic gel injection,there were different degrees of capsule rupture and induration in 6 polyacrylamide hydrophilic gel injection,and the images showed sporadic callosities such as subcutaneous nodules and nodules in glands or muscles ; hydrogel migration in 8 polyacrylamide hydrophilic gel injection.Secondary deformity occured in 80 ％ cases,in which the most cases were induced by hydrogel migration.Conclusions Magnetic resonance imaging can make clear of the type of rupture and the distribution leakage of polyacrylamide hydrophilic gel for facial plasty and it is an ideal approach for advanced patients with polyacrylamide hydrophilic gel injection for follow-up.