Giant aneurysm of the azygos pericallosal artery: case report and review of the literature

BACKGROUND: Pericallosal aneurysms are encountered less than 6.7%, and giant aneurysms among them even less. Giant azygos pericallosal artery aneurysm at the callosomarginal bifurcation is extremely rare, and our case presented herein is the second one. The case is discussed with thorough review of the literature. METHODS: A 65-year-old woman presented with an extremely rare giant aneurysm on the azygos pericallosal artery manifesting as subarachnoid hemorrhage in World Federation of Neurosurgical Societies Grade 3. Computed tomography (CT), magnetic resonance angiography (MRA), and four vessel angiography revealed a giant azygos pericallosal artery aneurysm associated with a second aneurysm at the left M1. RESULTS: After recovery to Grade 2, she underwent surgery via the right frontal interhemispheric approach for the azygos artery aneurysm on the 17th day after bleeding. The true dimensions of the aneurysm were greater than indicated by angiography because of partial thrombosis. Trilobulate aneurysm was carefully dissected from the surrounding structures. Postoperative cerebral angiography showed no filling of the clipped aneurysm and preservation of circulation. CONCLUSIONS: The treatment of distal anterior cerebral artery aneurysms is often difficult, because of their broad-based irregular configurations and adherence to surrounding tissue, tendency to bleed irrespective of size and the coexistence of other cerebral aneurysms. However, excellent outcomes can be obtained based on thorough preoperative radiologic evaluation, including magnetic resonance imaging (MRI), and correct selection of surgical approach.     

Dissecting aneurysm of the anterior cerebral artery requiring surgical treatment--case report

A 45-year-old male presented with spontaneous dissecting aneurysm in the anterior cerebral artery manifesting as headache persisting for several days and speech disturbance. Neurological and laboratory examinations showed no abnormalities. Magnetic resonance imaging revealed infarction in the right cingulate gyrus. Angiography revealed occlusion of the right A2. Repeat angiography 8 months later showed a saccular aneurysm had developed. The interhemispheric approach exposed the aneurysm at the junction between the right frontopolar artery and the pericallosal artery. The aneurysm was fusiform due to the right A2 dissection. The aneurysm was trapped and resected. One month after the operation, the patient was discharged without neurological deficits. Cases of dissecting aneurysms in the anterior cerebral artery with ischemic onset are usually treated conservatively. Cases requiring surgery include those due to trauma, growing aneurysms, giant aneurysms, and uncontrolled hypertension. Some dissecting aneurysms of the distal anterior cerebral artery require only resection without bypass surgery.     

Giant aneurysm of the pericallosal artery causing acute subdural hematoma--case report

A 66-year-old female presented with a very rare giant aneurysm of the distal pericallosal artery. She lost consciousness and was admitted. Computed tomography demonstrated a subdural hematoma over the left cerebral convexity and a mass in the frontal lobe. Cerebral angiography disclosed a giant aneurysm located on the distal segment of the right pericallosal artery. The subdural hematoma was removed and the aneurysmal neck was clipped, but she died 15 days after the operation. Autopsy found the giant aneurysm (33 x 30 x 27 mm) on the distal segment of the right pericallosal artery. Highly atheromatous changes were recognized in part of the aneurysmal wall, the arteries near the circle of Willis, and the distal anterior cerebral artery (ACA) adjacent to the aneurysm. There were no anomalous vessels such as azygos ACA. Giant aneurysms situated beyond the genu of the corpus callosum are extremely rare. Atherosclerosis was probably a major etiological factor in this case.     

Bilateral distal anterior cerebral artery aneurysm associated with supreme anterior cerebral artery: case report]

A 67-year-old woman presented with bilateral distal anterior cerebral artery aneurysms manifesting as consciousness disturbance. Computed tomography revealed subarachnoid hemorrhage in the interhemispheric fissure, right sylvian fissure, and a hematoma in the right frontal lobe and lateral ventricles. Angiography showed bilateral symmetrical aneurysms located on the pericallosal artery at the bifurcation of the callosomarginal artery. The operation was performed on the day the patient was admitted. The aneurysms were clipped via the interhemispheric approach, and the hematoma was aspirated. Operative view demonstrated rupture of the left aneurysm, and supreme anterior cerebral aneurysm. Postoperative angiography showed disappearance of the aneurysms and an intact bilateral anterior cerebral artery. The patient was discharged with mild organic mental syndrome. However, a few days later, she was admitted again with a high fever and died of complications due to sepsis. Pathological view showed clipped aneurysms and the connection of the bilateral distal anterior cerebral artery with the so-called supreme anterior communicating artery.     

Aneurysm of peripheral cerebral arteries with developmental anomaly of the anterior cerebral artery

We report a 71-year-old woman who was initially admitted because of a ruptured internal carotid aneurysm, and found to have an aneurysm of the terminal portion (A5 portion) of pericallosal artery. Both of the aneurysms were surgically treated at one stage operation. A saccular aneurysm of the pericallosal artery was verified at operation. Right internal carotid angiography disclosed that medial part of the right anterior cerebral hemisphere was supplied by the right callosomarginal artery, and that unpaired pericallosal artery made a trifurcation at A5 portion, where the saccular aneurysm arose. According to Baptista's classification, anomaly of the anterior cerebral artery (ACA) in this patient was bihemispheric ACA type. Distal ACA aneurysms almost always locate at or near the genu of corpus callosum, either in pericallosal-callosomarginal or in pericallosal-frontopolar junction. In reviewing the literature, we were able to find 14 cases, including ours, of aneurysms located beyond either pericallosal-callosomarginal junction or the genu of corpus callosum. Also the possible role of hemodynamic stress caused by vascular anomaly for aneurysm formation are discussed.     

Traumatic pericallosal aneurysm in a patient with no major trauma. Case report

The case of a young woman who developed a traumatic distal anterior cerebral artery ("pericallosal") aneurysm from a roller-coaster ride is described. She presented with a subarachnoid hemorrhage (SAH) restricted to the interhemispheric fissure. The initial angiogram was normal but repeat angiography at 8 days revealed the aneurysm. After craniotomy and clipping the patient made a satisfactory recovery. This is the only reported case of a traumatic aneurysm arising under circumstances not usually considered as trauma. It raises questions about the pathophysiology of the formation of such aneurysms and suggests that traumatic pericallosal aneurysms should be considered in SAH of unknown etiology. This case provides further evidence that repeat angiography occasionally helps reveal an aneurysm when the initial study fails to do so.     

Multiple fungal aneurysms: report of a rare case implicating steroid as predisposing factor

A 61-year-old man with a ruptured aneurysm of the anterior communicating artery developed hemorrhagic cerebral infarction 22 days after an operation associated with occlusion of the right angular artery. Angiograms further revealed sequential changes of intracranial vessels including progressive obstructions of the right anterior and middle cerebral arteries and four aneurysms on the left pericallosal artery. Subsequently, the patient became comatose and died. At autopsy the newly formed aneurysms originating from the left pericallosal artery were of fungal (Phycomycetes) origin and numerous nonseptate, branching hyphae were also seen in the obstructed cerebral arteries. Intracranial fungal aneurysms are reviewed in the literature and the pathogenesis in the present case is discussed.     

Giant pericallosal artery aneurysm: case report and review of the literature

Pericallosal artery aneurysms comprise 5% of all intracranial saccular aneurysms and are usually small. Giant cerebral aneurysms mostly occur in major arteries. To date, 12 cases of giant pericallosal artery aneurysm have been reported in the literature. An unusual giant thrombosed pericallosal artery aneurysm is reported here. A 65-year-old female presented with headache and personality changes. Computed tomography, magnetic resonance imaging, and cerebral angiography revealed a right-sided giant thrombosed pericallosal artery aneurysm. The patient was operated via an anterior interhemispheric approach and the neck of the aneurysm was successfully clipped. The postoperative period was uneventful. This rare lesion is one of few cases presented in the literature in which neuroradiologic and neuropathologic evaluation was completely performed and the neck of the aneurysm was clipped. Received: 14 November 2000 / Accepted: 4 January 2000     

Spontaneous disappearance of aneurysm after total removal of accompanying intracranial arteriovenous malformation. Case report]

A 55-year-old male was hospitalized with severe headache. On admission, neurological examination revealed no abnormal findings. Plain computed tomography (CT) showed a slightly high-density area in the medial surface of the right parietal lobe. A marked enhancement in the same region was noted in enhanced CT. Cerebral angiography showed an arteriovenous malformation (AVM) in the medial surface of the right parietal lobe and two aneurysms on the right pericallosal artery which fed the AVM. In addition, a saccular aneurysm was noted at the anterior communicating artery. It was not possible to treat the AVM, two aneurysms nearby the AVM, and the unruptured anterior communicating artery aneurysm simultaneously with a single craniotomy. It was therefore decided to perform surgery for the AVM and two aneurysms nearby the AVM prior to clipping of the anterior communicating artery aneurysm. Total excision of the AVM and two aneurysms nearby the AVM was performed. Cerebral angiography performed 18 days after surgery revealed no AVM and also reduction in size was noted of the anterior communicating artery aneurysm. Three months later, repeated cerebral angiography showed disappearance of the aneurysm. This was further confirmed 15 months after surgery by angiography. From the literature, 117 cases of coexistence of AVM and aneurysms of the brain were collected and classified into three types according to their anatomical and hemodynamic correlation. It is suggested that hemodynamic stress, due to increased blood flow caused by the AVM, played a major role in the development of the aneurysm.(ABSTRACT TRUNCATED AT 250 WORDS)     

An aneurysm of the distal anterior cerebral artery with a remarkably anomalous configuration

A case of aneurysm on the distal anterior cerebral artery with a remarkably anomalous configuration was reported. In the present case, the left anterior cerebral artery showed hairpin-like angulation, at the top of which a small saccular aneurysm was noticed. This anomalous anterior cerebral artery seemed to feed the territories of the fronto-orbital artery and the pericallosal artery. Although the incidence of distal anterior cerebral artery aneurysm is low, they are very interesting due to several characteristics. According to the reported cases of distal anterior cerebral artery aneurysms, acute angulation of the parent vessel, at the top of which saccular aneurysm is often noticed, and the hemodynamic stress has been considered to play important roles in aneurysm formation. The findings of the cerebral angiograms and the operation of the present case were demonstrated.     

A case of iatrogenic traumatic intracranial aneurysm

A case of traumatic aneurysm due to an arterial injury during removal of a tuberculum sellae meningioma is reported. A 43-year-old man had undergone craniotomy for removal of the tumor. It was very hard with many feeders from bilateral anterior cerebral arteries (ACA), so the resection between the left ACA and the tumor was difficult. A small artery was accidentally pulled out from the left ACA and bleeding occurred from the small artery in the artery. The ACA was trapped temporarily with two clips and was coated using Oxycell and Biobond. The bleeding was stopped by this procedure and the blood reflowed. This tumor was removed totally, but postoperative CT scan showed an enhancing small lesion in the anterior part of the left basal ganglia 10 days after operation. The angiograms performed next day revealed a fusiform aneurysm of the left proximal ACA near the anterior communicating artery. The skull was reopened to treat the aneurysm. The aneurysm arising from just a bleeding point in the previous operation was oval in shape without neck, so it was trapped by two small aneurysm clips and resected. The patient's condition was uneventful after the second operation. Pathological diagnosis of the aneurysm was confirmed a false aneurysm. Iatrogenic traumatic aneurysms caused by neurosurgical procedure has been reported in 29 cases. Eighteen cases showed bleeding from injured artery during surgery and a half of them showed rupture from the aneurysm within one month after operation. Such doubtful cases of traumatic aneurysm should be diagnosed by angiography and operated as early as possible.     

Stent-assisted coiling of an acutely ruptured large aneurysm of the internal carotid artery: case report

A 48-year-old female was referred to our hospital for the management of a ruptured 22-mm-diameter internal carotid aneurysm, located immediately distal to the ophthalmic artery. The right internal carotid artery was completely involved in the aneurysm. Because the right carotid siphon was relatively nontortuous stent-assisted coiling of the aneurysm was attempted 4 days after subarachnoid hemorrhage. A new coil-type coronary stent, a DRIVER stent, was deployed after microcatheter insertion into the aneurysm dome under systemic heparinization, followed by dome packing using Guglielmi detachable coils. Systemic heparinization was continued for 18 hours postoperatively, and aspirin (100 mg/day) was administered orally immediately after the embolization. However, 4 hours after heparin administration cessation, left hemiparesis became apparent. Immediate magnetic resonance angiography revealed a right internal carotid artery occlusion. Diffusion-weighted images demonstrated ischemic spots in the watershed zones of the right cerebral hemisphere. Following an immediate thrombolysis of the right internal carotid artery, systemic heparinization was continued for 5 days, and aspirin and ticlopidine were administrated orally. The patient was discharged on day 37, following the recovery from left hemiparesis within ten days. A DRIVER stent is a low profile coil-type coronary stent, which can be used for the stent-assisted coiling of large internal carotid aneurysms, located distal to the carotid siphon. It seems necessary to continue systemic heparinization for more than 2 days and to administer increased dose or two types of antiplatelet after the stent-assisted coiling of large cerebral aneurysms.     

Traumatic cerebral aneurysm showing remarkable extravasation into the lateral ventricle--report of a case in an infant (author's transl)

A case of traumatic cerebral aneurysm showing remarkable extravasation into the lateral ventricle was reported. This 9-month-old female baby fell down from 30 cm height and hit the right occipital area against the concrete floor. Immediately after the accident she cried, but three minutes later apnea and cardiac arrest were developed. On admission, plain craniogram showed a linear skull fracture extending from the parietal to occipital area on her right side. Since the retrograde vertebral angiography performed through the right brachial artery revealed no finding of hematoma, the patient was treated conservatively. On the third day from the accident, she developed convulsion on her right leg and the left CAG showed an aneurysm of 5 mm X 3 mm size at C2 portion of the carotid artery but no hematoma was detected. As plain craniograms taken with intervals revealed progressive suture separation, V-P shunt was performed. Immediately after the operation, mydriasis was noted on the left side. The left CAG showed remarkable extravasation of the contrast medium from the aneurysm into the left lateral ventricle. Trapping of the aneurysm was performed and the clot was removed out of the left lateral ventricle as much as possible. Ten months after surgery, she was able to eat. Development and treatment of traumatic aneurysms and extravasation from aneurysms of various origin have been discussed.     

Etiological factors and surgical treatment of pericallosal aneurysm

In spite of the belief that pericallosal bifurcation is the predilectional site for aneurysm, only a few reports have so far been available. Since 1963 nine cases of such aneurysms have been encountered at the Yamaguchi University Hospital. All aneurysms located on so-called pericallosal bifurcation at the genu of the corpus callosum. Seven aneurysms were saccular and two were fusiform. Multiple aneurysms were found in one case, while another case had a combined arteriovenous malformation at the periphery of the aneurysm. In one case, the internal carotid artery on the opposite side was occluded. Seven of the 9 patients were treated surgically. Ligation of the afferent artery was performed in the case with combined arteriovenous anomaly. Direct attack to the aneurysm was safely done in the remaining 6 cases through interhemispheric approach, neck clipping in 3 cases and adhesive coating in 3. Postoperative results were excellent in all cases but one, in which postoperative meningitis developed. In view of the disastrous outcome of pericallosal aneurysm when left alone, we believe that the direct surgical attack is the treatment of choice. Fortunately, an aneurysm at this site can be handled easier and safer than deep seated aneurysms in connection with Willis's circle, since it can be approached by interhemispheric route.     

De novo formation and rupture of an azygos pericallosal artery aneurysm. Case report

An azygos pericallosal artery (APCA) aneurysm is a rare anomaly that is closely associated with saccular aneurysms. This is the earliest report to document de novo formation and rupture of an aneurysm at the bifurcation of an unpaired pericallosal trunk. The authors report the case of a woman who presented at the age of 52 years with subarachnoid hemorrhage (SAH) from the rupture of a newly formed APCA bifurcation aneurysm, 7 years after she had undergone surgery to clip a ruptured anterior cerebral artery aneurysm. De novo formation of aneurysms after SAH rarely occurs and certain risk factors like multiple and familial aneurysms, arterial hypertension, or smoking have been postulated. Late follow-up examination with angiography to detect de novo aneurysms should be considered in patients with this vascular anomaly after SAH.     

A case showing the infraoptic course of the anterior cerebral artery associated with anterior cerebral artery aneurysm

A ruptured anterior cerebral artery aneurysm with anomalous right infraoptic course of the anterior cerebral artery (ACA) was reported. A 40-year old male was admitted because of SAH episode, and computerized tomography (CT) on the day of admission revealed hemorrhage in both Sylvian and interhemispheric fissures. Four-vessel angiography was performed on the same day. A saccular aneurysm was demonstrated in the region of the anterior communicating artery (ACoA), and anomalous artery, which originated from the intradural right carotid artery at the level of the right ophthalmic artery was found to be running medially and superiorly. It supplied the bilateral callosomarginal arteries and the unpaired pericallosal artery. The fenestration of the vertebral artery, duplication of bilateral superior cerebellar arteries, and an occipital artery arising from the right internal carotid artery at the C3 level were found. Surgery was performed on the first day of admission, and the anterior interhemispheric approach was selected. The anomalous branch of the right ICA ran beneath the right optic nerve, ascended between the optic nerves, and supplied the ACoA system. The left hypoplastic A1 segment entered the ACoA. However, the right A1 segment could not be found. The aneurysmal neck, situated between the bilateral callosomarginal arteries and the unpaired pericallosal artery, was clipped with Sugitas curved clip. The postoperative course was uneventful and a follow-up angiograph revealed successful obliteration of the aneurysm.     

Traumatic false aneurysm of the middle meningeal artery causing an intracerebral hemorrhage: case report and literature review

BACKGROUND: Traumatic false aneurysms of the meningeal arteries are rare. We report an unusual case of an intracerebral hematoma caused by the rupture of a traumatic aneurysm of the middle meningeal artery. CASE DESCRIPTION: A 64-year-old woman suffered a massive spontaneous intracerebral fronto-temporal hemorrhage. Cerebral angiogram revealed a pseudoaneurysm of the middle meningeal artery. At operation, a skull fracture was discovered in the vicinity of the aneurysm. The patient died the day after surgery. CONCLUSION: Although rare, traumatic meningeal aneurysms should be considered as a possible cause of cerebral hematoma. Because of their potential morbidity and mortality, they must be detected and treated rapidly.     

A ruptured aneurysm in the hypoplastic proximal anterior cerebral artery (A1 portion); case report

A case of ruptured aneurysm in the hypoplastic proximal anterior cerebral artery (A1 portion) is reported. This 25-years old man complained of the sudden onset of severe headache and vomiting on January 11, 1989. He was referred to our hospital on the same day, and CT scan revealed subarachnoid hemorrhage. Cerebral angiography on the next day revealed an aneurysm in the hypoplastic A1 portion of the right anterior cerebral artery, and no branch was present at the site of the aneurysmal neck. He was operated on using the right pterional approach. The A1 portion was trapped and the aneurysm was removed successfully. The histology of the aneurysm was that of the usual type of the saccular aneurysm. The post-operative course was uneventful. He was discharged with no neurological deficit two months after the operation. As far as we know, there has been no report on a ruptured aneurysm in the hypoplastic A1 portion. We also reviewed the 55 aneurysms in the A1 portion that have been reported in the literature.     

Giant aneurysm of the pericallosal artery

A rare case of a giant aneurysm of the pericallosal artery, evaluated by computed tomography, magnetic resonance imaging, and angiography, is reported, and the other 7 cases in the literature are reviewed. Giant aneurysms are exceptional in the distal segments of the anterior cerebral arteries, and may simulate a callosal tumor or hematoma on computed tomographic scan. The clinical, radiological, surgical, and pathological findings of giant aneurysms of this location are discussed and the other reported cases are analyzed. The role of magnetic resonance imaging in diagnosing and characterizing giant aneurysms is stressed.     

The early hemorrhage and development of a bacterial aneurysm after a cerebral ischemic attack caused by a septic embolism--a case report]

A 71-year-old female was admitted with the complaints of dysarthria and right hemiparesis. CT scan revealed subarachnoid hemorrhage in the left cerebral sulcus. The first angiography was performed 3 days after the onset and left carotid angiography revealed a small aneurysm arising from the left middle cerebral artery. After 3 weeks of antibiotic therapy, the second angiography showed the aneurysm to be clearly enlarged, so it was resected. The patient complained of marked dysarthria a day after the operation and CT scan revealed a new infarction in the right frontal lobe. The third angiography showed an aneurysm arising from the right middle cerebral artery and the fact that two peripheral arteries of the aneurysm had disappeared 3 weeks after the first operation. The second operation was performed and a bacterial aneurysm was resected. The patient left the hospital without any neurological deficits. Septic embolism is the most important complication of infective endocarditis and it is usually presented with subarachnoid hemorrhage and intracerebral hemorrhage caused by ruptured bacterial aneurysms. In this case the septic embolism occurred two times. At each time cerebral ischemic attacks were presented. The reason why this case presented with ischemic symptoms was suspected to be that embolisms occurred at the trifurcation of the distal middle cerebral arteries. We were able to detect a bacterial aneurysm angiographically 3 days after the ischemic attack and we suspected that a bacterial aneurysm had been able to develop within 3 days after the septic embolism.