Analysis of radiation scatter during angiographic procedures: evaluation of a phantom model and a modified radiation protection system.
OBJECTIVE
To study the radiation scattering associated with the digital subtraction angiography (DSA) unit in angiographic procedures and to design an effective radiation protection shield based on these data.


METHODS
The number of scattered photons was measured at three points relative to the operator's position. Anteroposterior abdominal and lateral cranial fluoroscopy were evaluated. As protective devices, a lead curtain, sliding shields, and a brim-shaped image intensifier (II) hood were designed.


RESULTS
In abdominal fluoroscopy, radiation was found to scatter to the operator's lower limbs from the underside of the catheter table, to the abdomen from the side of the patient's body, and to the head and neck from the table surface adjacent to the patient. The use of protective devices reduced exposure from 2.89 to 0.058 mR/min for the operator's lower limbs, from 0.987 to 0.069 mR/min for the operator's abdomen, and from 0.696 to 0.139 mR/ min for the operator's head and neck area. With lateral cranial fluoroscopy, radiation was detected to scatter to the operator's lower limbs from the underside of the catheter table, to the abdomen from the patient's temporal area, and to the head and neck from the patient's face. The use of protective devices reduced exposure from 0.248 to 0.010 mR/min for the operator's lower limbs, from 0.129 to 0.010 mR/min for the operator's abdomen, and from 0.162 to 0.018 mR/min for the operator's head and neck area.


CONCLUSIONS
The characteristic directions of scattering to the operator were identified. An effective modified radiation protection system was designed based on this information.
Ito
H
H
Department of Radiology, Yamagata University School of Medicine, Yamagata City, Japan. hitoh@med.id.yamagata-u.ac.jp
Hosoya
T
T
Eguchi
Y
Y
Adachi
M
M
Watanabe
Y
Y
Yamaguchi
K
K
D000005:Abdomen / Q000528:radiation effects; D015901:Angiography, Digital Subtraction; D004867:Equipment Design; D006257:Head / Q000528:radiation effects; D006801:Humans; D007866:Leg / Q000528:radiation effects; D009333:Neck / Q000528:radiation effects; D019047:Phantoms, Imaging; D011832:Radiation Injuries / Q000517:prevention & control*; D011835:Radiation Protection / Q000295:instrumentation*; D011874:Radiometry; D012542:Scattering, Radiation