Visualization of C7-T1 on portable lateral cervical spine radiographs using a lead-lined acrylic filter.

Abstract

To determine whether lead-lined acrylic cervical filters can improve the quality of portable lateral cervical spine (c-spine) radiographs for trauma patients. Twenty trauma patients who required portable c-spine x-rays had these taken with a lead filter attached to the collimator of the portable x-ray machine to improve penetration and visualization of lower cervical structures without overpenetrating upper cervical structures. The radiographs of these patients were compared with the first portable c-spine radiographs without filters for 20 controls matched for gender and injury severity. The comparison of radiographs was done by an experienced emergency physician and a neuroradiologist blinded to whether the filter was used. The two groups were similar for demographic and clinical characteristics. There was a significant improvement in the ability to visualize the C7-T1 level for the filter group compared with the control group (65% vs 30%, p < 0.05). Agreement between the physicians was excellent (kappa = 0.79, 95% CI = 0.60-0.99). Lead-lined acrylic filters improve the ability to visualize the lower c-spine in trauma patients.