Dissecting aneurysms at the A1 segment of the anterior cerebral artery--two case reports

Two rare cases of dissections which involve the anterior cerebral artery (ACA) are reported. A 58-year-old woman presented with a ruptured dissecting aneurysm manifesting as sudden onset of severe headache and consciousness disturbance followed by aphasia, right hemiparesis, paresis of the left lower extremity, and choreoathetotic movements of the upper arms and face. Computed tomography and angiography revealed subarachnoid hemorrhage due to a dissecting aneurysm at the left A1 segment. The dissecting aneurysm was trapped surgically on the day of onset. Her neurological deficits disappeared within a month. A 39-year-old woman experienced continuous dull headache from the day before onset, and then suffered right hemiparesis. Magnetic resonance (MR) imaging revealed cerebral infarction at the left globus pallidus. Angiography and MR imaging revealed a dissecting aneurysm at the left A1 segment and occlusion of the left Heubner's artery. She received conservative treatment and her neurological findings were improved. Dissections or dissecting aneurysms involving the ACA can be classified into three types: Extension of a dissection to the ACA from the internal carotid artery, dissection at the A1 segment, and dissection at the A2-A4 segments. These types of dissection have distinct uniform clinical features.     

Subarachnoid hemorrhage in a case of segmental arterial mediolysis with coexisting intracranial and intraabdominal aneurysms

The authors report the rare case of a 58-year-old man with segmental arterial mediolysis (SAM) with associated intracranial and intraabdominal aneurysms, who suffered subarachnoid hemorrhage (SAH) due to rupture of an intracranial aneurysm. This disease primarily involves the intraabdominal arterial system, resulting in intraabdominal and retroperitoneal hemorrhage in most cases. The patient presented with severe headache and vomiting. The CT scans of the head revealed SAH. Cerebral angiography revealed 3 aneurysms: 1 in the right distal anterior cerebral artery (ACA), 1 in the distal portion of the A(1) segment of the right ACA, and 1 in the left vertebral artery. The patient had a history of multiple intraabdominal aneurysms involving the splenic, gastroepiploic, gastroduodenal, and bilateral renal arteries. He underwent a right frontotemporal craniotomy and fibrin coating of the dissecting aneurysm in the distal portion of the A(1) segment of the right ACA, which was the cause of the hemorrhage. Follow-up revealed no significant changes in the residual intracranial and intraabdominal aneurysms. An SAH due to SAM with associated multiple intraabdominal aneurysms is extremely rare. The authors describe their particular case and review the literature pertaining to SAM with associated intracranial and intraabdominal aneurysms.     

Serial angiography and endovascular treatment of dissecting aneurysms of the anterior cerebral and vertebral arteries. Case report.

This 47-year-old man was admitted to the hospital with disturbance of consciousness due to subarachnoid hemorrhage caused by a ruptured dissecting aneurysm of the left anterior cerebral artery (ACA). Conservative treatment resulted in improvement in the patient's consciousness; however, repeated rupture occurred during the chronic stage. Endovascular coil embolization of the parent artery was successful. Serial angiography demonstrated all stages in the development of the aneurysm. Follow-up angiography demonstrated an incidental dissecting aneurysm of the right vertebral artery. This aneurysm was also treated by endovascular embolization. No new neurological deficit appeared during or after the treatment. Multiple dissecting aneurysms are rare, especially those involving both supra- and infratentorial regions. A ruptured dissecting aneurysm of the ACA is also an uncommon vascular disorder. This case shows that rebleeding may occur, even during the chronic stage, and thus appropriate treatment for the prevention of subsequent bleeding is essential. Incidental dissecting aneurysms can be treated using the endovascular technique, but further study is necessary.     

Dissecting aneurysms of the vertebrobasilar system. A comprehensive review on natural history and treatment options

Vertebral artery dissection has been recognized as an uncommon cause of ischemic stroke. However, it is less well known as a cause of subarachnoid hemorrhage. Even if dissecting aneurysms of the vertebral artery are rare, their importance arise from their high morbidity and mortality with rebleeding occurring more often than in cases of saccular aneurysms. Dissecting aneurysms of the vertebrobasilar system are a complex entity which requires a rapid and effective treatment to prevent rerupture. The sole stenting technique stands as a promising approach, allowing to occlude the aneurysm while preserving the vessel patency and reconstructing the diseased segment.     

Dissecting posterior inferior cerebellar artery aneurysm presenting with subarachnoid hemorrhage right after anticoagulant and antiplatelet therapy against ischemic event

BACKGROUND: Dissecting aneurysms with initial ischemic manifestations may present with subsequent subarachnoid hemorrhage (SAH), and their treatment is controversial. This is a case report that illustrates the dilemma when dealing with an immediate post-SAH period dissecting posterior inferior cerebellar artery (PICA) aneurysm initially presenting with an ischemic event. METHODS: We present a 57-year-old man with a dissecting PICA aneurysm who had SAH right after anticoagulant and antiplatelet therapy for cerebral infarction. The aneurysm was not detected by magnetic resonance angiography performed at the time of admission. RESULTS: On admission, he was treated with both anticoagulant and antiplatelet therapy. After the SAH episode, he underwent emergent resection of the dissecting aneurysm and left OA-PICA anastomosis. CONCLUSION: If hemorrhagic transformation occurs at the site of an ischemic dissecting aneurysm, surgical or endovascular intervention should be considered immediately. Although the optimal treatment of dissecting aneurysms with ischemic onset remains controversial, anticoagulant and antiplatelet therapy should not be rejected out of hand.     

Agenesis of the right internal carotid artery associated with complicated anastomosis of middle cerebral artery: a case report

A 57-year-old female was admitted to our hospital because of headache, nausea, and vomiting. Head CT scan demonstrated subarachnoid hemorrhage. Cerebral angiography showed the absence of the right internal carotid artery, and skull base CT of the bone window level revealed the absence of the right carotid canal. The right middle cerebral artery (MCA) and anterior cerebral artery (ACA) were opacified from the left internal carotid artery. The right A1 portion was hypoplastic and the distal portion of the right M1 portion was replaced by several minute complicated anastomotic vessels connected to the right M2 portion. The right MCA territory was mainly supplied by collateral flow from the right ACA and the right posterior cerebral artery via the leptomeningeal anastomosis. These was neither aneurysm nor arteriovenous malformation. The second angiography, 1 week after the initial angiography, showed the same hemodynamic pattern and aneurysms were not found. We diagnosed the patient as agenesis of the right internal carotid artery and the etiology of subarachnoid hemorrhage was suspected to be a rupture of the anastomotic vessels between the right M1 and M2. She was discharged on the 21st hospital day without any neurological deficit.     

Ruptured distal accessory anterior cerebral artery aneurysm--case report

A 48-year-old man presented with an extremely rare aneurysm arising from an accessory anterior cerebral artery (ACA) manifesting as sudden onset of headache lasting for 5 days. Neurological examination on admission revealed no abnormalities. Computed tomography showed subarachnoid hemorrhage of the interhemispheric fissure and intraparenchymal hematoma of the left cingulate gyrus. Magnetic resonance and cerebral angiography revealed a saccular aneurysm of the distal portion of the accessory ACA classified as the bihemispheric type. Neck clipping of the aneurysm was performed via an interhemispheric approach 17 days after symptom onset. The patient made a good postoperative recovery without neurological deficit. Distal accessory ACA aneurysms tend to arise from the first bifurcation and supply parietal branches. The aneurysms tend to occur on the bihemispheric type of distal accessory ACA. Hemodynamic stress may contribute to formation or development of these aneurysms.     

Ruptured dissecting aneurysm of the vertebral artery missed by initial angiography; case report]

Dissecting aneurysm of the intracranial arteries is a well known clinical entity, and its angiographic findings are also well recognized. We encountered a case with dissecting aneurysm of the vertebral artery presented with subarachnoid hemorrhage (SAH). The initial angiography was normal but repeated angiography demonstrated a dissecting aneurysm. This case is reported here, and the relevant literature is reviewed. A 46-year-old woman had been well until she complained of headache. She was admitted to a local hospital and found to have SAH. She was transferred to our clinic for further examination. On admission the patient was drowsy but able to be aroused. Her neurological state was normal except for a mildly stiff neck. Computed tomography (CT) demonstrated massive SAH in the basal cistern and intraventricular hemorrhage in all ventricles. CT also demonstrated acute hydrocephalus. Four-vessel cerebral angiography was performed using transfemoral catheterization. No definite abnormalities, except for a small aneurysm in the cavernous portion of the right internal carotid artery, were found. Because aneurysm in the cavernous portion could not cause SAH, we could not define the origin of the SAH. However, retrospectively, a slightly irregular wall of the left intracranial vertebral artery was evident. Repeated angiography performed 28 days later revealed aneurysmal dilatation of this left vertebral artery. Double density of the contrast material was found in the aneurysmal dilatation. Retention of the contrast medium was also seen in the late capillary phase. From these angiographic findings, the aneurysm was diagnosed as being a dissecting aneurysm. Direct surgical attack on the vertebral aneurysm was performed via a left suboccipital craniectomy.(ABSTRACT TRUNCATED AT 250 WORDS)     

Endovascular treatment of a ruptured aneurysm associated with unilateral moyamoya disease

We report a case presenting with subarachnoid hemorrhage due to a ruptured aneurysm associated with unilateral moyamoya disease. The patient was a 29-year-old woman exhibiting sudden onset headache. Computed tomography revealed subarachnoid hemorrhage around the brain stem. Cerebral angiography showed a saccular aneurysm at the junction of the left P1 portion of the posterior cerebral artery and its perforator. The right internal carotid artery was occluded at the terminal portion, and the right middle cerebral artery territory was perfused anterogradely via abnormal moyamoya vessels in the basal ganglia. The aneurysm was completely embolized with preservation of the perforator. We suggest that as compared to surgical clipping by craniotomy, endovascular therapy is safe and effective for treatment of intracranial aneurysms associated with moyamoya disease.     

Anterior cerebral artery dissections manifesting as cerebral hemorrhage and infarction,and presenting as dynamic angiographical changes--case report

A 65-year-old woman presented with multiple dissecting aneurysms of the anterior cerebral artery (ACA) manifesting as hemiparesis on the right with dominance in the lower extremity. Computed tomography revealed hematoma in the left frontal lobe, corresponding to the area perfused by the callosomarginal artery. Initial angiography showed string sign and occlusion in the distal portion of the left callosomarginal artery and abnormal feeding suggesting double lumen of the A2 portion of the left ACA. The patient was treated conservatively under a diagnosis of multiple spontaneous dissecting aneurysms of the left ACA. Repeat angiography on Day 8 showed improvement of the string sign and occlusion in the left callosomarginal artery, and change of the double lumen of the A2 portion into string sign. Further angiography on Day 36 showed normalization of the left callosomarginal artery and improvement of the string sign in the A2 portion. Multiple spontaneous dissecting aneurysms of the ACA are extremely rare. Serial angiography beginning in the early stage will be important for correct diagnosis.     

Dissecting aneurysm of the anterior cerebral artery with persistent pearl & string sign on cerebral angiograms over a period of eight years]

We present a rare case of a dissecting aneurysm of the left anterior cerebral artery (ACA) with persistent pearl & string sign on cerebral angiograms over a period of 8 years. A 43-year-old woman with disturbance of consciousness and right sided hemiparesis was conservatively treated. Computed tomographic (CT) scan revealed a low-density area in the left frontal lobe. Initial angiography, which was performed at 6 months after the onset, showed a pearl & string sign at the A2 portion of the left ACA. After 8 years, repeat angiography again showed persistent pearl & string sign at the same portion of the left ACA. We discussed the changes in findings usually obtained in cerebral angiography concerning dissecting aneurysms in ACA.     

Dissecting aneurysm confined to the anterior cerebral artery

Dissecting aneurysm confined to the anterior cerebral artery (ACA) is extremely rare. Four patients presented with dissecting aneurysms confined to the ACA, two with cerebral infarctions in the territories of the ACA and two with subarachnoid haemorrhages. The two patients with infarction were treated by conservative therapy with anti-platelet therapy and the two patients with subarachnoid haemorrhage were treated by wrapping surgery in the early period after the ictus. Conservative treatment for patients with infarction and early wrapping surgery for patients with subarachnoid haemorrhage are recommended.     

Multiple spontaneous dissecting aneurysms of the anterior cerebral and vertebral arteries

A 50-year-old woman presented with rare multiple dissecting aneurysms that appeared first in the anterior cerebral artery (ACA) and shortly afterwards in the vertebral artery (VA). She initially suffered sudden motor weakness in the left lower limb due to acute brain infarction. Angiography revealed diffuse string sign in the right ACA. Conservative treatment resulted in resolution of the deficits. Follow-up angiography performed 1 year later revealed recovery of the ACA stenosis. Fourteen days later, she complained of sudden headache and became comatose. Computed tomography showed diffuse subarachnoid hemorrhage. Angiography revealed a new right VA dissecting aneurysm involving the posterior inferior cerebellar artery (PICA). The orifice of the dissection was not apparent in the operative field and the dissection extended to the median. The patient underwent extracranial right VA ligation, clipping of the proximal PICA, and revascularization between the right occipital artery and distal PICA. Her postoperative course was uneventful and she was discharged without neurological deficits. VA dissecting aneurysms involving the PICA without evident orifice or extending over the median can be treated by extracranial ligation with clipping of the PICA, followed by revascularization.     

"Kissing" aneurysms of the internal carotid artery treated by coil embolization

A 62-year-old female complaining of sudden severe headache was referred to our stroke center in consultation. Computed tomography showed diffuse spread of thick subarachnoid hemorrhage to the basal cistern and both sylvian fissures, and digital subtraction angiography showed kissing aneurysms arising in the left lateral and occipital directions in the C(1) portion of the internal carotid artery (ICA). The anterior choroidal artery was situated between the two aneurysms, and another small branch originating from the dome of the distal aneurysm was confirmed as a duplicated middle cerebral artery (MCA). Endovascular treatment was successfully performed to spare the two vessels involved. This case of kissing aneurysms and ICA-duplicated MCA is very rare, and presents difficulties for both surgical and endovascular treatments.     

A middle cerebral artery dissecting aneurysm manifesting solely with pain, following a vertebral artery dissecting aneurysm

A 41-year-old male had presented with severe neck pain and was diagnosed as having a left vertebral artery (VA) dissecting aneurysm. During the observation period, he suddenly suffered from a pain on his left temple. MR imaging revealed neither SAH nor cerebral infarction. MR angiography, computed tomographic (CT) angiography and cerebral angiography showed fusiform dilatation of the M1 portion of the left middle cerebral artery (MCA) which had been normal in the former study. The abnormality of the left MCA normalized on both MR and CT angiography 6 months after the second onset. Because of the chronological change of radiological findings compatible with the symptom, we diagnosed the second episode as a MCA dissecting aneurysm manifesting with isolated pain. Among the previous forty-four MCA dissecting aneurysms, all but one case presented with hemorrhagic or ischemic event. In addition, this is the only case of multiple dissecting aneurysms of VA and MCA manifesting with isolated pain.     

Subarachnoid hemorrhage from intracranial dissecting aneurysms of the anterior circulation. Two case reports.

Two rare cases of intracranial dissecting aneurysms of the anterior circulation associated with subarachnoid hemorrhage (SAH) are described. A 56-year-old female presented with a dissecting aneurysm in the proximal segment of the left middle cerebral artery. Proximal occlusion of the affected artery and a superficial temporal artery-middle cerebral artery anastomosis were performed, but the outcome was poor. A 61-year-old male presented with a dissecting aneurysm in the proximal segment of the left anterior cerebral artery. Clipping was enhanced by a piece of fascia lata, allowing patency of the affected artery with a satisfactory outcome. Dissecting aneurysm of the carotid system should be considered in a patient with SAH but no evidence of berry aneurysm.     

Vertebrobasilar artery dissection presenting with simultaneous subarachnoid hemorrhage and brain stem infarction: case report

BACKGROUND: Intracranial dissecting aneurysms have been associated with subarachnoid hemorrhage (SAH) or cerebral ischemia. We encountered a patient presenting with simultaneous subarachnoid hemorrhage and brainstem infarction caused by a dissecting aneurysm of the vertebrobasilar artery, which was diagnosed by magnetic resonance imaging (MRI) but did not show abnormal findings on cerebral angiography. CASE DESCRIPTION: A 55-year-old man had sudden onset of headache and left abducens palsy. Computed tomography revealed a subarachnoid hemorrhage localized in the left prepontine cistern and the left cerebellomedullary fissure. Cerebral angiography showed neither a saccular aneurysm nor fusiform dilatation causing the subarachnoid hemorrhage. MRI demonstrated a small infarction in the left dorsal pons, and an intramural hematoma of the left vertebral artery and lower basilar artery. CONCLUSION: This is a rare case of a vertebrobasilar dissecting aneurysm that simultaneously caused both SAH and brain stem infarction. MRI should be performed in the acute phase of SAH of unknown origin to determine the possible coexistence of a dissecting aneurysm, as occurred in this case.     

Vertebrobasilar junction aneurysms associated with fenestration: experience of five cases treated with Guglielmi detachable coils

BACKGROUND: Fenestration of vertebrobasilar junction is a rare congenital anomaly and often associated with aneurysm formation. We describe five cases of vertebrobasilar junction aneurysms in four patients associated with fenestration, which were treated with endovascular coil occlusion using Guglielmi detachable coils (GDCs). The importance of preoperative computed tomography (CT) angiography to understand the complex anatomy of fenestration and aneurysm is emphasized. CASE REPORTS: Three patients presented with subarachnoid hemorrhage and one patient presented with headache only. Among 3 patients with subarachnoid hemorrhage, 1 patient was referred for endovascular coil occlusion after clipping of ruptured distal ACA aneurysm. A six-French guiding catheter was placed in the left vertebral artery via right femoral artery, except for 1 patient who had two vertebrobasilar junction aneurysms with complex anatomic relationship, accessed bilaterally. Five vertebrobasilar junction aneurysms with fenestration were treated with endovascular coil occlusion using GDCs. Postoperative angiography demonstrated successful occlusion of aneurysmal sac with preservation of basilar artery. CONCLUSIONS: Vertebrobasilar junction aneurysms are frequently associated with fenestrations. In addition to vertebral angiography on both sides, CT angiography may be a valuable tool for better understanding of complex anatomy of aneurysms associated with fenestration. The surgically difficult aneurysms such as vertebrobasilar junction aneurysm with fenestration can be successfully treated with GDCs.     

Intra-operative hemorrhage due to hyperperfusion during direct revascularization surgery in an adult patient with moyamoya disease: a case report

Hemorrhagic complication is one of the notable surgical complications of the revascularization surgery for moyamoya disease (MMD). Cerebral hyperperfusion (CHP) has been considered as the underlying cause of this complication. It mostly occurs several days after surgery, but the intra-operative hemorrhage immediately after bypass has not been reported previously. A 21-year-old woman presented right thalamic hemorrhage and was diagnosed as having MMD by cerebral angiography. In light of the location of the hemorrhage at the vascular territory of posterior circulation and the manifestation of transient ischemic attack during the follow-up period, she underwent revascularization surgery to prevent future ischemic attack and rebleeding. Superficial temporal artery (STA) was uneventfully anastomosed to the temporal M4 branch of the middle cerebral artery in an end-to-side manner. A few minutes after the completion of the anastomosis, hemorrhage occurred in the fissure adjacent to the site of anastomosis. Indocyanine green (ICG) video angiography just before hemorrhage showed focal early filling through the STA graft with early venous filling around the site of the anastomosis. The bleeding was controlled by immediate hypotensive therapy (systolic blood pressure 117 to 91 mmHg). The mean blood flows of the STA graft measured by ultrasonic flowmetry before and after hypotensive therapy were 52.8 and 24.2 ml/min, respectively. Single-photon emission computed tomography (SPECT) on the next day after surgery showed focal hyperperfusion in the surgical side. Intra-operative ultrasonic flowmetry, ICG, and postoperative SPECT would explain that CHP was the potential cause of the hemorrhagic complication. This is the first case describing intra-operative hemorrhagic complication during revascularization surgery for MMD. Surgeons need to be aware of this rare complication and its management method.     

A case of Rathke's cleft cyst in association with a ruptured aneurysm of the anterior cerebral artery mimicking pituitary apoplexy

We present a rare case of a Rathke's cleft cyst in association with a ruptured aneurysm of the anterior cerebral artery (ACA). A 44-year-old man suffered from sudden onset of headache. Initial computed tomographic (CT) scan revealed a high-density mass lesion in the suprasellar region and a diffuse high-density area in the basal cistern. Using emergent magnetic resonance imaging (MRI), we found a cyst showed homogeneously high and iso-intensity on T1 and T2-weighted image, respectively. The cyst showed no enhancement of the cyst wall, but on Gd-DTPA, it was shown to compress the normal pituitary gland. Angiography showed an aneurysm at the A1 portion of the left ACA. Based on/these findings, we were able to diagnose Rathke's cleft cyst and a ruptured aneurysm. An operation was performed through the interhemispheric approach. The suprasellar cystic mass compressed the optic nerves and chiasm upward. Neck clipping of the aneurysm and opening of the cyst were performed. We confirmed the cause of the subarachnoid hemorrhage as being a ruptured aneurysm at the A1 portion of the left ACA. Histological diagnosis was Rathke's cleft cyst. Postoperative course was uneventful. There has been only one reported case of Rathke's cleft cyst in association with a ruptured aneurysm. When we encounter a case presenting subarachnoid hemorrhage with suprasellar mass and intracerebral aneurysm, we must discriminate between ruptured aneurysm and pituitary apoplexy in the acute stage as the cause of the subarachnoid hemorrhage. If the mass is Rathke's cleft cyst, we speculate that the cause of the subarachnoid hemorrhage is a ruptured aneurysm, because there are no reports of Rathke's cleft cyst with subarachnoid hemorrhage.