The authors evaluated the amount of radiation that patients and surgeons are exposed to while using both a standard c-arm and mini-c-arm devices. Previous studies have found that radiation exposure from use of the mini-c-arm is consistently less than that from use of a standard c-arm, and some have suggested that it is negligible. The author’s criticism of these studies was that they generally studied the exposure based on ideal configurations of patient and c-arm (patient positioned as far from radiation source as possible) and while imaging small body parts (generally hand and wrist). Clearly these conditions may not represent real working conditions in which patients are frequently repositioned and when the mini-c-arm is used to evaluate structures larger that the hand.
In this study exposures were measured at best and worst case configurations while imaging a foot and ankle. The authors found that radiation exposure doubled with use of the standard vs. the mini-c-arm. As expected, they found that radiation exposure was increased dramatically with improper positioning of the object being imaged. Interestingly they found that under a worst case configuration (with object positioned closest to the radiation source) the radiation exposure to the patient from the mini-c-arm was 5 times greater than with use of the standard c-arm in a best case configuration (object positioned closest to the image intensifier). The radiation exposure to the surgeon was equivalent under these two circumstances.
This study shows that contrary to popular belief, the patient and surgeon can be exposed to considerable radiation with use of the mini-c-arm. It underscores the importance of following dose reducing recommendations during fluoroscopy, and the authors recommend the use of a lead garment even when using the mini-c-arm.