WEB, Woven EndoBridge
KAP, kerma-area product
ESD, entrance skin dose
RAK, reference air kerma
DSA, digital subtraction angiography
Intrasaccular flow disruption is a new and effective endovascular treatment for intracranial aneurysms. While endovascular treatment is a minimally invasive procedure, it does carry a radiation risk. As radiation dose should be kept as low as reasonably achievable (ALARA), the main objective of this study was to analyse KAP (kerma area product), fluoroscopy and procedure time during the treatment of aneurysms treated with coiling and the Woven-EndoBridge (WEB) device. A secondary objective was to look at the reference air kerma (RAK) to determine if the patient receives a dose that could cause tissue effects.
KAP, fluoroscopy and procedure time were retrospectively analysed in patients who had an aneurysm treatment. Aneurysms with diameters of 4-11mm, over a four-year period, in the anterior and posterior circulation of the brain were analysed in this study. Patients were treated by coiling or WEB. RAK were summed together in the working projection to give an estimated entrance surface dose (ESD) in cases with the highest KAP.
A total of 47 aneurysms treated with WEB and 104 aneurysms treated with coiling techniques met the inclusion criteria. The average KAP was 6884.1 ± 2774.4µGym2 with coiling techniques and 5658.7 ± 1602.5µGym2 with WEB (p=0.006; CI =363-2086µGym2). This demonstrates an 18% reduction with WEB. Mean fluoroscopy time for coiling was 63.5 ± 42.6minutes and 33.8 ± 28.8minutes for WEB (p=<0.001; CI=16-43minutes). Fluoroscopy time was reduced by nearly 50% with WEB. On average, there was a 27-minute reduction of procedure time when using WEB compared to coiling. The RAK determined for the working projections did not exceed the 2Gy threshold for tissue effects.
Treatment of aneurysms using the WEB shows a reduction in KAP, fluoroscopy, and procedure time. This study further demonstrates the benefits of intrasaccular flow disruption for treatment of intracranial aneurysms.