Pulsation and Collimation During Fluoroscopy to Decrease Radiation: A Cadaver Study

Awareness of the harmful effects of long-term low-dose radiation is rising. Many studies have assessed both patient and physician exposure to radiation in association with the use of fluoroscopy in the operating room. However, to our knowledge, previous studies have not assessed, in a detailed fashion, the reduction in radiation exposure that pulsation and collimation provide.

Seven fresh cadavers were irradiated for 5 minutes with C-arm fluoroscopy with use of standard x-ray and pulsed and collimated x-ray beams. The x-ray sources were placed under the table, over the table, and lateral to the table. Radiation exposure doses were measured at different points, such as the center of the radiation field on the cadaver as well as at the locations of the surgeon's hand and thyroid gland. In addition, Monte Carlo simulation (a physics equation to predict exposure) was performed to estimate the dose reduction and to confirm the experimental results.

The radiation exposure doses associated with the use of pulsed fluoroscopy (8 times per second) were reduced by approximately 30% for the patient and by approximately 70% for the surgeon's hand and thyroid gland as compared with those associated with the use of continuous fluoroscopy. The radiation exposure doses associated with the use of collimated beams were reduced to approximately 65% for the surgeon's hand and thyroid gland as compared with those associated with the use of non-collimated fluoroscopy. These results were consistent with the simulation, and the phenomena could be appropriately explained by physics.

The present study revealed the effectiveness of pulsed and collimated x-ray beams in reducing radiation exposure doses resulting from C-arm fluoroscopy. Surgeons should consider using the techniques of pulsed fluoroscopy and collimation to protect patients and themselves from radiation.

This study presents data regarding the reduction of radiation exposure provided by pulsed fluoroscopy and collimation.