Patient knowledge regarding radiation exposure from spinal imaging

Background Context

Spine surgeons employ a high volume of imaging in the diagnosis and evaluation of spinal pathology. However, little is known regarding patients' knowledge of the radiation exposure associated with these imaging techniques.

Purpose

To characterize spine patients' knowledge regarding radiation exposure from various imaging modalities.

Study Design/Setting

A cross-sectional survey study.

Patient Sample

One hundred patients at their first clinic visit with a single spine surgeon at an urban institution.

Outcome Measures

The primary outcome was patient estimate of radiation dose for various common spinal imaging modalities as compared with true dose.

Methods

An electronic survey was administered to all new patients before their first appointment with a single spinal surgeon. The survey asked patients to estimate how many chest x-rays (CXRs) worth of radiation were equivalent to various common spinal imaging modalities. Patient estimates were compared to true effective radiation doses determined from the literature. The survey also asked patients whether they would consider avoiding types of imaging modalities out of concern for excessive radiation exposure.

Results

Patients accurately approximated the radiation associated with two views of the cervical spine, with a median estimate of 3.5 CXRs, compared with an actual value of 4.7 CXRs. However, patients underestimated the dose for computed tomography (CT) scans of the cervical spine (2.0 CXRs vs. 145.3 CXRs), two views of the lumbar spine (3.0 CXRs vs. 123.3 CXRs), and CT scans of the lumbar spine (2.0 CXRs vs. 638.3 CXRs). The majority of patients believed that there is at least some radiation exposure associated with magnetic resonance imaging (MRI). The percent of patients who would consider forgoing imaging recommend by their surgeon out of concern for radiation exposure was 14% for x-rays, 13% for CT scans, and 9% for MRI.

Conclusion

These results demonstrate a lack of patient understanding regarding radiation exposure associated with common spinal imaging techniques. These data suggest that patients might benefit from increased counseling and/or educational materials regarding radiation exposure before undergoing diagnostic imaging of the cervical or lumbar spine.