PMC4628205_01
Preoperative digital subtraction angiography (DSA) showing a ruptured aneurysm at the basilar bifurcation, which extended superiorly to the midbrain (A). Computed tomography showing diffuse subarachnoid hemorrhage in the basal cistern (B). Note that no perianeurysmal edema was detected preoperatively. The aneurysm was obliterated with GDCs , with a slight neck remnant (C). Postoperative fluid attenuated inversion recovery sequence with magnetic resonance imaging detected perianeurysmal edema, which resolved spontaneously (arrow in D).
nmc-55-519-g1.jpg
PMC4628205_01_nmc-55-519-g1.jpg
F1
Computed tomography studies of the brain confirmed subarachnoid hemorrhage (Fisher grade 3) with hydrocephalus, and digital subtraction angiography demonstrated an aneurysm at the basilar bifurcation, which extended superiorly to the midbrain (Fig. 1A, B). Bare platinum coils (GDC , Boston Scientific, Natick, Massachusetts, USA) were used for embolization with balloon neck remodeling technique, which resulted in a occlusion with a slightly neck remnant (Fig. 1C). Interestingly, asymptomatic perianeurysmal edema was detected in the midbrain on fluid attenuated inversion recovery sequence with magnetic resonance imaging (FLAIR-MRI) 2 weeks after the initial treatment (Fig. 1).
Follow-up DSA showing aneurysm recanalization and regrowth (A) with a perianeurysmal edema on FLAIR-MRI 8 weeks after the initial treatment (B). Second embolization with Matrix , Micrus Coil , and GDC  enabled complete obliteration of the aneurysm (C), but induced massive perianeurysmal edema in the midbrain (arrow in D). The edema was asymptomatic and spontaneously resolved a week after the 2nd embolization (double arrow in E). DSA: digital subtraction angiography, FLAIR-MRI: fluid attenuated inversion recovery-magnetic resonance imaging.
nmc-55-519-g2.jpg
PMC4628205_01_nmc-55-519-g2.jpg
F2
Follow-up angiogram demonstrated aneurysm recanalization and regrowth, with a perianeurysmal edema again on FLAIR-MRI 8 weeks after the initial treatment (Fig. 2A, B), but she presented no obvious neurological symptoms. She underwent re-embolization with bioactive coils and bare platinum coils (Matrix , Micrus Coil , and GDC ) 9 weeks after the initial treatment, and complete occlusion was achieved (Fig. 2C). However, perianeurysmal edema massively deteriorated on postoperative FLAIR-MRI at 2 days after the procedure (Fig. 2D), which was spontaneously improved 4 weeks later (Fig. 2E).
Follow-up DSA showing aneurysm recanalization and regrowth again (A) with a perianeurysmal edema on FLAIR-MRI 16 weeks after the initial treatment (arrow in B). Third embolization with GDC  enabled complete obliteration of the aneurysm (C), which achieved with a slight improvement of the edema (D). DSA: digital subtraction angiography, FLAIR-MRI: fluid attenuated inversion recovery-magnetic resonance imaging.
nmc-55-519-g3.jpg
PMC4628205_01_nmc-55-519-g3.jpg
F3
Follow-up angiogram demonstrated aneurysm recanalization and regrowth again in parallel with asymptomatic perianeurysmal edema on FLAIR-MRI 16 weeks after the initial treatment (Fig. 3A, B). She underwent the 3rd embolization with GDC  31 weeks after the initial treatment, and complete occlusion was achieved (Fig. 3C). FLAIR-MRI 2 days after the third treatment revealed a slight improvement of the edema (Fig. 3C).