Radiation Exposure in Aneurysmal Subarachnoid Hemorrhage

Introduction: Modern diagnosis and management of aneurysmal subarachnoid hemorrhage depends heavily on imaging that repeatedly exposes patients to ionizing radiation during their initial hospitalization. Sources of exposure include computed topography (CT) scans, CT angiography, CT perfusion studies, and digital-subtraction angiography. While the individual radiation dose from these sources is well defined, the cumulative radiation dose in this patient population is poorly understood and lightly considered in decision-making. We seek to define the cumulative radiation dose aneurysmal subarachnoid hemorrhage patients receive at our institution during their primary admission and compare radiation exposure between surgical versus endovascular management of ruptured aneurysms.

Methods: This study retrospectively reviewed adult patients who were admitted to our institution between January 1, 2018 and December 31, 2019 for aneurysmal subarachnoid hemorrhage. Patient aneurysm location, mode of securing the aneurysm, number, type, and radiation dose of imaging studies were recorded from the primary hospital admission for a ruptured cerebral aneurysm. Defined volume CT dose index (CTDIvol) for the CT scanners at our institution were used to determine the average mGy patients received in CT studies. Data was analyzed using an unpaired t-test to determine statistical significance.

Results: Preliminary work identified a total of 53 patients that met the inclusion criteria for this study. Of these aneurysms, 40 were secured with endovascular coiling and 13 were secured with clipping. On average, patients with aneurysms that were coiled received 3.9 CT head scans without contrast, 1.1 CT angiography head scans, 0.3 CT perfusion scans, and 1.6 angiograms. In comparison, patients with aneurysms that were clipped received 2.8 CT head scans, 1.7 CT angiography head scans, 0.6 CT perfusion scans, and 1.8 angiograms. The average cumulative radiation dose in patients who were managed with endovascular coiling was 5,694 versus 2,536 mGy in patients treated with surgical clipping (p = 0.0014).

Conclusion: Patients admitted for aneurysmal subarachnoid hemorrhage receive potentially harmful cumulative radiation doses during their primary hospitalization. Average irradiation is significantly higher in patients with ruptured aneurysms that are treated with endovascular coiling under fluoroscopy relative to aneurysms that are secured with surgical clip ligation.

Publication History

Article published online:
12 February 2021