Infra-posterior inferior cerebellar artery aneurysm arising after occlusion of the ipsilateral vertebral artery--case report.

An 85-year-old woman had subarachnoid hemorrhage due to rupture of a very rare left infra-posterior inferior cerebellar artery (PICA) aneurysm, a saccular aneurysm located proximally at the junction of vertebral artery (VA) and PICA. Right vertebral angiography demonstrated the aneurysm since the left VA was occluded in the extracranial portion. The aneurysm projected in the opposite direction to common VA-PICA aneurysms. The angiographical and intraoperative findings imply this rare aneurysm resulted from the hemodynamic changes caused by the VA occlusion. Detailed exploration of angiography is emphasized to detect such rare aneurysms among the diversity of hemodynamic patterns in elderly patients with subarachnoid hemorrhage.     

Isolated intraventricular hemorrhage due to a ruptured vertebral artery aneurysm

A rare case of ruptured aneurysm originating from the vertebral artery, and presenting an isolated clot in the fourth ventricle is reported. The patient underwent surgery via a right lateral suboccipital craniectomy on the third day. As the aneurysm was huge and partially thrombosed, trapping was performed and completed successfully. If isolated intraventricular hematoma was found without obvious parenchymal hemorrhage or subarachnoid clot, the diagnosis of vertebral artery aneurysm should be considered as a possibility in addition to posterior inferior cerebellar artery aneurysm. Complete vertebral angiography is indispensable for the recognition of this condition.     

Cerebellar hemorrhage after coil embolization for a ruptured vertebral dissecting aneurysm

BACKGROUND: We present a case of ruptured vertebral dissecting aneurysm that exhibited cerebellar hemorrhage after successful embolization of the vertebral artery including the dissected site. CASE PRESENTATION: A 59-year-old man suffered a sudden onset of severe occipital headache when he looked up. Computed tomography demonstrated subarachnoid hemorrhage. Angiography revealed a right vertebral dissecting aneurysm distal to the posterior inferior cerebellar artery. Endovascular embolization of the aneurysm was performed with preservation of the posterior inferior cerebellar artery. The next day, the patient suffered a cerebellar hemorrhage in the vermis. The intracranial pressure was controlled by external ventricular drainage. The patient was discharged with mild cerebellar ataxia and bilateral abducens nerve palsy. CONCLUSION: In a case of vertebral dissecting aneurysm distal to the posterior inferior cerebellar artery, blood circulation in the vertebral arterial system may change after embolization of the aneurysm. In our case, the preserved posterior inferior cerebellar artery might have been hemodynamically stressed postoperatively, resulting in cerebellar hemorrhage. Therefore, strict control of blood pressure is essential in the acute stage after occlusion of the aneurysm.     

Perimedullary arteriovenous fistula at the craniocervical junction - case report -

Perimedullary arteriovenous fistulas (AVFs) at the craniocervical junction are uncommon, and are often fed by the anterior spinal artery, with only a few cases fed by the intradural vertebral artery (VA). A 55-year-old man presented with a case of perimedullary AVF fed by the VA at the craniocervical junction manifesting as subarachnoid hemorrhage. Left vertebral angiography demonstrated an AVF supplied by branches from the VA. Three-dimensional computed tomography angiography (3D-CTA) revealed that the feeding arteries originated from the VA at the intradural position. Two feeding arteries were coagulated and dissected, followed by coagulation of a small feeder. The draining veins became discolored and shrank. 3D-CTA performed 2 months after the operation revealed disappearance of the AVF. Open surgery was successfully performed for the almost perimedullary AVF at the craniocervical junction, and is considered to be preferable for the treatment of this disease.     

Familial cerebral aneurysms in three families, with two sibling pairs

The authors describe two pairs of siblings and a mother-son with cerebral aneurysms and the characteristics of familial intracranial aneurysms are briefly discussed. Family 1: A 54-year-old hypertensive woman (case 1) developed subarachnoid hemorrhage and a saccular aneurysm at the proximal portion of the left anterior cerebral artery was demonstrated on the angiogram. An azygos anterior cerebral artery was found as an associated anomaly. A 53-year-old hypertensive woman (case 2), a younger sister of case 1, suffered from subarachnoid hemorrhage and a saccular aneurysm at the distal portion of the right anterior cerebral artery was found on the angiogram. Vertebral angiogram showed bilateral fenestration of the extracranial vertebral arteries as a coincidental anomalies. Neck clipping for the aneurysms were successfully done in these two cases. Family 2: A 52-year-old hypertensive woman (case 3) suffered from subarachnoid hemorrhage and vertebral angiogram demonstrated a saccular aneurysm at the distal portion of the right posterior inferior cerebellar artery. The aneurysm was re-bled before surgical intervention and she died five days after admission. A 65-year-old hypertensive woman (case 4), an elder sister of case 3, was admitted with subarachnoid hemorrhage. Vertebral angiogram showed a saccular aneurysm on the proximal portion of the left posterior inferior cerebellar artery at the junction of the vertebral artery and a massive extravasation of the contrast medium from the aneurysm. The patient died three days after the onset before surgical intervention.(ABSTRACT TRUNCATED AT 250 WORDS)     

Ruptured pseudoaneurysm following Gamma Knife surgery for a vestibular schwannoma

A 75-year-old woman underwent Gamma Knife surgery (GKS) for a vestibular schwannoma. Eight years after GKS, she suffered sudden onset of headache. Computed tomography revealed diffuse subarachnoid hemorrhage around the cisterns of the posterior fossa. Right vertebral artery angiography showed an aneurysm arising from the lateral pontomedullary segment of the left anterior inferior cerebellar artery. The aneurysm was not located at a branching site. Trapping of the distal anterior inferior cerebellar artery aneurysm was performed, and the aneurysm was removed. The pathological features of this aneurysm are discussed. This aneurysm was diagnosed as a pseudoaneurysm pathologically. This is the first report of aneurysm formation with pathological findings following GKS for a vestibular schwannoma.     

Dissecting vertebral aneurysm with subarachnoid hemorrhage after ischemic onset on the same day: a case report

We report a case of a dissecting vertebral aneurysm with subarachnoid hemorrhage (SAH) after ischemic onset on the same day. A 48-year-old man had abrupt vertigo and nausea. CT & MRI on admission showed no abnormality, but he complained of left hemiparesis after admission. Twelve hours after the ischemic onset he suddenly complained of severe headache and his consciousness deteriorated. The follow-up CT showed diffuse SAH. Cerebral angiography showed occlusion of the right vertebral artery at the origin of the posterior inferior cerebellar artery (PICA) and segmental stenosis of the left vertebral artery at the portion distal to the vertebral PICA junction. We treated the patient conservatively. Four days later, he suddenly fell into a coma, but CT showed no bleeding. Because of this we suspected brain stem ischemia due to deterioration of vertebral dissection. The patient died 8 hours after the ischemic reattack. We report difficulty of treatment of a dissecting vertebral aneurysm with simultaneous ischemia and subarachnoid hemorrhage.     

Ruptured vertebral artery dissecting aneurysm followed by spontaneous acute occlusion and early recanalization: case report

A 47-year-old man presented with a ruptured vertebral artery dissecting aneurysm manifesting as subarachnoid hemorrhage followed by acute occlusion and early recanalization of the affected artery. Cerebral angiography 2 hours after the onset of the symptom showed pearl-and-string sign in the right vertebral artery. Serial angiography showed that the affected artery was occluded at 12 hours but was recanalized on the 4th day. The dissecting aneurysm was resected with side-to-side anastomosis between the bilateral posterior inferior cerebellar arteries. Postoperative cerebral angiography demonstrated disappearance of the lesion and patency of the right posterior inferior cerebellar artery via the anastomosis. Histological examination of the lesion showed hematoma between the media and adventitia, disrupting the internal elastica and intima. Acute occlusion and early recanalization of the affected artery may occur in ruptured vertebral artery dissecting aneurysms. Serial neurological and neuroradiological examinations are essential to decide the timing and method of treatment.     

Aneurysm of the distal posteroinferior cerebellar artery of extracranial origin: case report

OBJECTIVE AND IMPORTANCE: We describe a very rare case involving a ruptured intracranial aneurysm at the distal posteroinferior cerebellar artery (PICA) branching from the extracranial vertebral artery. CLINICAL PRESENTATION: A 53-year-old woman experienced the sudden onset of a severe occipital headache and vomiting. Computed tomographic scanning revealed subarachnoid and intraventricular hemorrhage. Cerebral angiography of the left vertebral artery demonstrated the left PICA branching from the extracranial segment of the extracranial vertebral artery at the level of C2; a saccular aneurysm arose from the intracranial portion of the distal PICA. INTERVENTION: Via the transcondylar approach, we were able to obtain adequate visualization without retracting important structures. To avoid injury to the anomalous PICA, the aneurysm was clipped. CONCLUSION: Only four other cases of a distal aneurysm of the PICA branching from the extracranial vertebral artery have been reported in the literature. In all cases, the aneurysm originated at the intradural extracranial portion of the PICA. To our knowledge, the case presented here is the first report of a ruptured aneurysm at the level of the intracranial portion of the PICA branching from the extracranial segment of the vertebral artery.     

Bilateral anomalous posterior inferior cerebellar artery-anterior inferior cerebellar artery anastomotic arteries associated with a ruptured cerebral aneurysm--case report

A 50-year-old man presented with subarachnoid hemorrhage from a ruptured cerebral aneurysm arising from a left posterior inferior cerebellar artery (PICA)-anterior inferior cerebellar artery anastomotic artery manifesting as severe headache, obtundation, and quadriplegia. Conventional and three-dimensional digital subtraction angiography showed that the anastomotic complex was present bilaterally and both vertebral arteries terminated at the origin of the PICA. The identification of this anomalous vascular network allowed coil embolization of the broad-based aneurysm with occlusion of the parent artery. The patient had residual moderate disturbance of consciousness and quadriplegia before transfer for rehabilitation.     

Subarachnoid hemorrhage caused by posterior inferior cerebellar artery aneurysm with an anomalous course of the atlantoaxial segment of the vertebral artery. Case report and review of literature

Various anatomical courses of the vertebral artery (VA) and posterior inferior cerebellar artery (PICA) have been described. The authors present a unique case of a subarachnoid hemorrhage resulting from an aneurysm in a patient with an anatomical variation of the extracranial portion of the VA and cervical origin of the PICA. The surgical implications of this variant are discussed, and the pertinent literature reviewed. Subarachnoid hemorrhage caused by rupture of a PICA aneurysm is reported for the first time in association with a rare variation of the course of the VA.     

Posterior inferior cerebellar artery aneurysm associated with persistent primitive hypoglossal artery

A 49-year-old woman presented with subarachnoid hemorrhage (SAH) from an aneurysm associated with a persistent primitive hypoglossal artery (PPHA) manifesting as sudden onset of headache, but without neurological deficits. Conventional computed tomography (CT) of her head showed no abnormality but lumbar tap indicated SAH. Three-dimensional (3D)-CT angiography showed a PPHA originating from the internal carotid artery and an aneurysm of the posterior inferior cerebellar artery at the junction with the remnant hypoplastic vertebral artery. 3D-CT angiography was essentially useful for presurgical planning to determine the extent of craniotomy and the space for possible temporary clipping, and confirmed the diagnosis of aneurysmal SAH. The aneurysm was clipped and she returned to her job 4 weeks later. Cerebral angiography is the golden standard technique to diagnose PPHA, but 3D-CT angiography can be recommended for presurgical evaluation, especially in patients with complex and anomalous anatomical structures.     

Ruptured aneurysm at an anastomotic artery extending from the vertebral artery to the posterior inferior cerebellar artery: a case report

A 51-year-old hypertensive man presented with subarachnoid haemorrhage. He had a past history of cerebellar infarction due to occlusion of the right posterior inferior cerebellar artery (PICA) 4 years earlier. Digital subtraction angiography showed a saccular aneurysm above an arterial loop extending from the vertebral artery to the distal part of the PICA, reminiscent of peripheral PICA branches. We performed aneurysmal neck clipping with excellent outcome. Aneurysms at anastomotic arteries are extremely rare and can result from increased haemodynamic stress. We report the first case of a ruptured aneurysm at an anastomotic artery in the posterior circulation territory.     

Anterior inferior cerebellar artery aneurysm, carotid bifurcation aneurysm, and dural arteriovenous malformation of the tentorium in the same patient

An exceptional combination of intracranial vascular malformations is reported: distal anterior inferior cerebellar artery (AICA) aneurysm, carotid bifurcation aneurysm, and dural arteriovenous malformation (DAVM) of the tentorium. The AICA aneurysm was the source of recurrent subarachnoid and cerebellar hemorrhage, revealed only after repeated vertebral angiography. After external drainage of associated hydrocephalus, both aneurysms were successfully clipped and the dural malformation was subtotally embolized. The literature concerning AICA aneurysms, DAVMs, and combined intracranial vascular malformations is reviewed and discussed.     

Surgical repair of aneurysms of the posterior inferior cerebellar artery--a clinical series

Aneurysms of the posterior inferior cerebellar artery are relatively rare. Fourteen such aneurysms (10 vertebral, 4 peripheral) are reported, and their clinical presentation, surgical therapy, and outcome are discussed. All 14 patients had suffered a subarachnoid hemorrhage; 93% (n = 13) underwent direct clipping of the aneurysm while 7% (n = 1) underwent coating of the aneurysm. Two patients died in the perioperative period (one from vasospasm and one from rebleeding). Full activity was achieved by all but one (92%) of the remaining patients in extended follow-up.     

Dissecting aneurysm of the posterior inferior cerebellar artery; a case report]

A case of a dissecting aneurysm of the left posterior inferior cerebellar artery caused by giant cell angiitis is presented. A 22-year-old woman was admitted on August 30, 1990, with sudden onset of severe occipital headache and vomiting. Neurological examination on admission only showed severe meningismus. CT scan demonstrated subarachnoid hemorrhage and a small hematoma in the 4th ventricle. A left vertebral angiogram demonstrated that the left posterior inferior cerebellar artery was occluded at the lateral medullary segment. We diagnosed subarachnoid hemorrhage from a dissecting aneurysm. On the day following admission, the patient underwent a left suboccipital craniectomy. The posterior inferior cerebellar artery was enlarged for a distance of about 8 mm and there was typical purplish-red appearance in the dissecting aneurysm. This aneurysm was excised after trapping. The histological diagnosis was primary localized giant cell angiitis without systemic involvement. The etiology of the intracranial dissecting aneurysm is obscure, but this report suggests that cerebral angiitis can be considered as an important factor.     

Subarachnoid hemorrhage caused by ruptured posterior inferior cerebellar artery aneurysm arising from the extracranial portion of an anomalous vertebral artery

A 42-year-old woman presented with subarachnoid hemorrhage caused by a ruptured posterior inferior cerebellar artery aneurysm arising from the extracranial portion of an anomalous vertebral artery. We speculated that the aneurysm formed by dissection of the media because of its shape and location. Therefore, the aneurysm was isolated by trapping and excised, with occipital artery to posterior inferior cerebellar artery bypass. Histological examination showed a typical true aneurysm without evidence of dissection. This case suggests that an aneurysm of an anomalous artery is caused by hemodynamic stress and is a true aneurysm, not a dissection.     

Multiple,peripheral aneurysms of the anterior inferior cerebellar artery

Summary In this case report, a 49-year-old woman developed subarachnoid hemorrhage in the right cerebellopontine angle cistern and blood into the fourth ventricle from a ruptured peripheral aneurysm of the anterior inferior cerebellar artery (AICA) located at the meatal loop. Concomitantly, a contralateral peripheral aneurysm was found in the posterior inferior cerebellar artery (PICA). A second peripheral aneurysm, not identified by previous angiography, was found in the caudomedial branch of AICA. We describe this diagnostic dilemma, management, and review the clinical presentation and location of 84 other peripheral AICA aneurysms reported in the literature.     

Spontaneous occlusion of ruptured vertebral artery dissection at the extradural fenestration associated with extradural origin of the posterior inferior cerebellar artery--case report

A 69-year-old female suffered from sudden onset of severe headache. Computed tomography showed subarachnoid hemorrhage primarily located in the posterior fossa. Initial angiography demonstrated a fenestration of the vertebral artery and an extracranial origin of the posterior inferior cerebellar artery. However, no bleeding points could be clearly detected. The operative findings revealed a massive clot in subarachnoid space, but no bleeding point. Serial angiography demonstrated dissection in one of the limbs of the fenestrated vertebral artery on the 25th day after the onset. On the 100th day, the lesion was spontaneously occluded. The patient is presently doing well at 8 years after surgery.     

A case of aneurysm at the junction of the vertebral artery and a spinal arterial branch

A 68-year-old male suffered from severe occipitalgia, nausea, and vomiting was admitted to our hospital. On admission, he complained only of headache and displayed no evidence of disturbed consciousness or neurological deficits. A computed tomographic (CT) scan revealed a subarachnoid hemorrhage in the basal subarachnoid cisterns, with the thickest, densest area in the bilateral ambient cisterns. Four-vessel angiograms disclosed no pathological findings. The patient was treated with bed rest and his blood pressure was maintained below 120 mmHg. Fortunately, no untoward events occurred during the period of bed rest, and a second vertebral angiogram was obtained 4 weeks after admission. At that time a vertebral artery aneurysm was discovered. At surgery a 3 X 3 X 3 mm aneurysm was found at the junction of the vertebral artery and a branch of the spinal artery. Small clots surrounding the aneurysm were removed. The aneurysm itself was easily clipped without destruction of the caudal cranial nerves and the patient recovered fully. The incidence of vertebral artery aneurysms is very small--about 5%. Moreover, to our knowledge an aneurysm on the proximal portion of the intracranial vertebral artery at the junction of the posterior-inferior cerebellar artery has never before been reported. On the other hand, our case might have been included among cases of subarachnoid hemorrhage of unknown etiology. The first cerebral angiogram revealed no aneurysm; it was found on the second set of angiograms. This case illustrates the importance of repeat angiography when the CT scan clearly shows a subarachnoid hemorrhage.