Thromboembolic Event Detected by Diffusion Weighted Magnetic Resonance Imaging After Coil Embolization of Cerebral Aneurysms

OBJECTIVE The purpose of this study was to evaluate the occurrence rate of diffusion positive lesions (DPLs), and to assess the peri-procedural risk factors for the occurrence of DPLs in patients who underwent coil embolization of cerebral aneurysms. MATERIALS AND METHODS A total of 304 saccular aneurysms were embolized during a seven-year period from Jan 2007 to Dec 2013. Of these, postoperative diffusion-weighted images were obtained in 186 procedures. There were 100 ruptured aneurysm and 86 unruptured aneurysms. The coiling procedures were as follows: simple coiling in 96, balloon assisted coiling (BAC) in 39, and stent assisted coiling (SAC) in 51 aneurysms. Clinical, angiographic and procedural factors were analyzed in relation to the occurrence of DPLs. RESULTS Overall, DPLs were observed in 50.5%. In unruptured aneurysms, DPLs occurred in 23.5% of BAC, 41.9% of SAC and 57.7% of simple coiling (p = 0.08). Among ruptured aneurysms, DPLs occurred in 63.6% of BAC, 62.5% of SAC and 54.3% of simple coiling (p = 0.71). DPLs had a tendency to increase in ruptured aneurysms compared with unruptured aneurysms (57% vs. 43%, p = 0.077). Logistic regression analysis revealed that age > 55 years was the only independent risk factor for the occurrence of DPLs. CONCLUSION DPLs occured more frequently in ruptured aneurysm and at an older age. Although most DPLs are asymptomatic, careful manipulation of cerebral or extracerebral arteries using various endovascular devices is important to reducing the occurrence of DPLs. BAC appeared to reduce occurrence of TE events in patient with unruptured aneurysm.