case_images: PMC3927094_01
case_images: Computed tomography (CT) of the patient at admission showed a thick subarachnoid hemorrhage (SAH) predominantly in the basal cistern and right Sylvian fissure (a). The SAH was spreading to the peripheral subarachnoid space and the brain seemed really tight (b). Three-dimensional CT angiography revealed an aneurysm arising from a distal point of the right middle cerebral artery bifurcation (c). Magnetic resonance (MR) angiography shows a clear image of the stalk-like and narrow aneurysm neck (d)
case_images: SNI-5-5-g001.jpg
case_images: PMC3927094_01_SNI-5-5-g001.jpg
case_images: F1
case_images: SAH, localized in the right sylvian fissure, and evidence of skull fracture [Figure 1]. Subsequent CT angiography indicated an aneurysm of the right M2, which was not at a bifurcation site [Figure 1]. Magentic resonance (MR) angiography revealed that the aneurysm had a stalk-like narrow neck.
case_images: Operative pictures of the aneurysm clipping. (a) The aneurysm was buried into the right frontal lobe (arrow). With parent artery trapping, the aneurysm was tentatively clipped. (b) Final view of the clipping. The aneurysm was carefully resected. There was no obvious arterial wall (asterisk). The aneurysm was located distal to the right middle cerebral artery bifurcation without an adjacent artery
case_images: SNI-5-5-g002.jpg
case_images: PMC3927094_01_SNI-5-5-g002.jpg
case_images: F2
case_images: A thin-walled, pseudo-looking aneurysm was found buried in the frontal lobe, but it appeared to be clippable [Figure 2]. A 5-mm bayonet-type clip (Sugita 2, Mizuho) was chosen and several attempts were made to close the ruptured hole without narrowing the parental artery [Figure 2].
case_images: Histopathological studies of the surgical specimen. (a) Hematoxylin and eosin (H and E) staining. The upper side is the vascular lumen. Atherosclerotic change was not observed. (b) Elastica van Gieson (EVG) staining shows thickened intima and mild invasion of inflammatory cells. (c) Masson's trichrome staining. (d) SMA (smooth muscle actin) immunohistochemistry. Staining reveals lack of smooth muscle cells in the tunica media. Scale bar: 600 mum
case_images: SNI-5-5-g003.jpg
case_images: PMC3927094_01_SNI-5-5-g003.jpg
case_images: F3
case_images: There was mild invasion of lymphocytes and plasmacytes, but no neutrophils [Figure 3]. There was no atherosclerotic change in the tunica intima, which is usually observed in cerebral aneurysms [Figure 3].
case_images: Computed tomography (CT) image acquired on the day of discharge showed an intact brain with a clip (a,b) CT angiography after 2 weeks showed obliteration of the aneurysm and ideal flow of the parent artery (c)
case_images: SNI-5-5-g004.jpg
case_images: PMC3927094_01_SNI-5-5-g004.jpg
case_images: F4
case_images: Two weeks later, CT angiography showed complete amelioration of the aneurysm and normal flow of the parent artery [Figure 4]. Plain CT after sugery also confirmed an intact brain [Figure 4].