Ruptured distal anterior cerebral artery aneurysms presenting as acute subdural hematoma--report of three cases.

The authors report three cases of distal anterior cerebral artery aneurysm presenting as acute subdural hematoma (SDH). Two patients were comatose on admission and died of massive SDH. One patient underwent aneurysmal neck clipping in the chronic stage and returned to normal daily life. A convexity SDH continuous with a wedge-shaped interhemispheric SDH was the characteristic computed tomographic appearance in all cases. There was no accompanying subarachnoid or intracerebral hemorrhage in one case (pure SDH). These cases are 9.4% of 32 ruptured distal ACA aneurysms treated in our institute in the last 14 years, a higher incidence than reported previously.     

Distal anterior cerebral artery mirror aneurysms and middle cerebral artery aneurysms

A 52-year-old woman presented with bilateral distal anterior cerebral artery (ACA) mirror aneurysms, in addition to two right middle cerebral artery (MCA) aneurysms. The left distal ACA and right MCA aneurysms were clipped through right interhemispheric and right pterional craniotomies. The right distal ACA aneurysm was thrombosed. Distal ACA aneurysms tend to be multiple, but mirror aneurysms are rare, especially in the absence of congenital vascular anomaly. Single stage unilateral craniotomy is recommended for surgical treatment.     

Surgical approach to giant intracranial aneurysms. Operative experience with 80 cases.

The authors report experience with the surgical management of 80 giant intracranial aneurysms (greater than 2.5 cm in diameter) during a 10-year period in which they performed 594 operations for aneurysms. The overall incidence of giant aneurysms was 13% but varied according to location: 20% of aneurysms of the internal carotid artery (ICA); 13% of middle cerebral artery (MCA) aneurysms; 1% of anterior cerebral artery (ACA) aneurysms; 15% of aneurysms of the basilar artery caput (BAC); and 18% of vertebrobasilar trunk (VB) aneurysms. Twenty-five patients had a subarachnoid hemorrhage (SAH), 49 had mass effect from the aneurysm, and six had ischemic events. There was no apparent difference in results related to the presence or absence of an SAH. Poor results were attributable to the operation except in the two cases of ACA aneurysm in which preexisting dementia persisted. Mortality was 4% and morbidity was 14%, varying from a combined low morbidity-mortality of 8% for ICA lesions to a high to 50% for BAC aneurysms. During the period of the study, different techniques were developed in an attempt to lower the risks of surgery. Ultimately ICA aneurysms were monitored with cerebral blood flow measurements and electroencephalography before and after temporary ICA ligation, then approached following resection of the anterior clinoid or treated with bypass in combination with ICA ligation. Aneurysms of the MCA were either opened during temporary MCA occlusion or resected in combination with a bypass procedure. Bypass grafts and circulatory arrest with extracorporeal circulation may have a role in giant aneurysms of the posterior circulation.     

Paraparesis associated with ruptured anterior cerebral artery territory aneurysms

BACKGROUND: Paraparesis is a rare but characteristic manifestation of ruptured anterior communicating artery or anterior cerebral artery (ACA) aneurysms, but the pathogenesis remains unclear. This study investigated the neuroimaging and clinical features of patients with such paraparesis to evaluate possible causes. METHODS: Nine of 178 patients with ruptured anterior communicating artery or ACA aneurysms presented with paraparesis among 462 patients with subarachnoid hemorrhage (SAH) admitted between May 1996 and November 2001. Diffusion-weighted magnetic resonance (MR) imaging was performed within 48 hours of the onset of SAH in 4 of these 9 patients. The clinical course and neuroimaging studies of these 4 patients were retrospectively reviewed. RESULTS: Diffusion-weighted MR imaging revealed -intensity areas in the medial aspects of the bilateral frontal lobes, which were supplied by the ACAs and distal to the aneurysms, in all 4 patients. These high-intensity lesions had normal to subnormal values of apparent diffusion coefficient (ADC). Most of the high-intensity lesions recovered and did not result in the final lesions regardless of the ADC values, but some lesions with subnormal ADC values resulted in cerebral infarction. Paraparesis was transient and almost completely resolved in 3 patients. CONCLUSIONS: Diffusion-weighted MR imaging detected primary brain damage in the ACA territories caused by acute SAH, which was compatible with the clinical paraparesis. Primary brain damage caused by SAH may include 3 types of lesions: reversible with normal ADC value, reversible with subnormal ADC value, and irreversible with subnormal ADC value.     

Spontaneous dissecting aneurysms of anterior and middle cerebral artery associated with brain infarction: a case report and review of the literature

BACKGROUND

Intracranial dissecting aneurysms have been reported with increasing frequency and are recognized as a common cause of stroke. In some reviews and case reports, attempts have been made to compare the outcomes of surgical and medical treatments. However, the appropriate management of dissecting aneurysms in the anterior circulation remains controversial, especially in patients who also manifest cerebral infarction.

CASE DESCRIPTION

A 45-year-old male was diagnosed as having a dissecting aneurysm of the right middle cerebral artery (MCA) with cerebral infarction. In the course of conservative treatment, he developed a new cerebral infarction in the territory of the right anterior cerebral artery (ACA). Repeat cerebral angiograms revealed an increase in the aneurysmal dilatation of the right M2 and the appearance of a segmental dilatation of the right A2. He continued to be treated conservatively and his course was satisfactory. On subsequent angiograms, we observed resolution of the right A2 dissection and no further progression of the dilatation of the right M2.

CONCLUSION

This is the first reported case of simultaneous idiopathic dissecting aneurysms of different major arterial branches in the anterior circulation. Our review of the literature disclosed 36 and 23 cases, respectively, of dissecting aneurysms of the ACA and MCA. Many previously reported patients with these dissecting aneurysms involving subarachnoid hemorrhage (SAH) underwent surgery, which resulted in better outcome. More than half of the patients with ACA and MCA dissecting aneurysms had cerebral infarction. All ACA dissecting aneurysms involving ischemia occurred in the A2 region. The outcomes of both surgical and conservative management were equally satisfactory. On the other hand, in patients with MCA dissecting aneurysms, the area of ischemia frequently involved the M1 region; in these patients, conservative treatment resulted in poor outcomes. Therefore, revascularization distal to the compromised artery should be considered in patients with MCA-dissecting aneurysms who have ischemia. Careful interpretation of serial angiograms and/or magnetic resonance (MR) images is necessary because of the possibility of disease progression. If the aneurysmal size increases or there is progression of ischemic symptoms in the course of conservative treatment, surgery must be urgently evaluated.     

Distal anterior cerebral artery aneurysm causing acute subdural hematoma: report of two cases

We report two cases of distal anterior cerebral artery aneurysms (distal ACA-aneurysm) causing acute subdural hematomas, which were diagnosed preoperatively. Case 1: 56 y.o. female who presented with stupor and right hemiparesis, was operated on 8 hrs. post-ictus. Case 2: 51 y.o. female who presented with semi-coma, anisocoria and decerebrate posture was operated on 5 hrs. post-ictus. She is alive in fair condition at present. Incidence of acute subdural hematomas in association with ruptured cerebral aneurysms has been reported as variously as 0.5 to 7.9% (clinical cases), with their source of bleeding being either IC or MCA aneurysms. Acute subdural hematomas as complication of ruptured distal ACA aneurysms are rare, and to the authors' knowledge, only 6 cases have been reported so far. Review of the literature regarding mechanism of formation of subdural hematoma, clinical course and treatment of choice are also reported.     

Fatal bleeding from arterial dissection after clipping of a ruptured aneurysm--case report

A 67-year-old man died of subarachnoid hemorrhage (SAH) resulting from dissection of the distal part of the anterior cerebral artery (ACA). A saccular aneurysm in the anterior communicating artery had ruptured and was successfully clipped on Day 0. The patient recovered consciousness after surgery but his condition deteriorated due to another SAH on Day 1. A second surgical procedure disclosed bleeding from a laceration in the opposite wall of the ACA distal to the clipped aneurysm. Histological examination of the autopsy specimens revealed damage to the internal elastic lamina and inflammatory infiltration of leukocytes. The fatal dissection may have resulted from atherosclerosis, hemodynamic stress caused by hypertension, or trauma due to surgical manipulation.     

Distal anterior cerebral artery aneurysms: report of 26 cases

Distal anterior cerebral artery (ACA) aneurysms are rare, and constitute approximately 1.5% to 9% of all intracranial aneurysms. They show some unique features compared with other aneurysms in the cerebral circulation and are frequently treated with a different technique. Twenty-six of 364 patients with cerebral aneurysms treated at our department between 1996 and 2004 had distal ACA aneurysms (7.1%). Twenty-three of the 26 patients were treated through an anterior interhemispheric approach and two with a pterional approach. All saccular aneurysms were successfully clipped except one which was embolized after the surgery. The only fusiform aneurysm spontaneously thrombosed and resolved with parent artery occlusion. Two of the 26 patients had multiple aneurysms. The surgical mortality was 8%. Distal ACA aneurysms have higher mortality and morbidity than other anterior circulation aneurysms. They should be aggressively treated even if very small because of the tendency to rupture. Endovascular treatment is an alternative in the management of these aneurysms. The most important factors affecting the outcome are grade on admission and the neurosurgeon's experience.     

Usefulness of CT angiography for demonstrating cerebral aneurysms

We report the usefulness of computed cerebral angiotomography (CT angiography) for demonstrating cerebral aneurysm and the clinical significance of CT angiography for ruptured cerebral aneurysm. Our modified method of CT angiography was easy and less time-consuming. Fifteen seconds after starting a single bolus injection, 1 ml/kg/25 seconds via cubital vein, of contrast medium (60% urograffin), 5 serial 5 mm thick-CT slices were scanned in every 6.5 seconds including 2 seconds of interval, beginning from an axial level 20 mm above the orbitomeatal line and ending at a level 40 mm. A total of 103 patients were examined in this report, consisting of 70 unruptured asymptomatic, 8 unruptured symptomatic (oculomotor nerve palsy) and 25 subarachnoid hemorrhage (SAH). Seven unruptured aneurysms in 4 asymptomatic cases, 2 unruptured aneurysms in 2 symptomatic cases 27 aneurysms in 24 SAH cases were suspected by CT angiography. Of these 36 aneurysms suspected by CT angiography 32 aneurysms were confirmed by cerebral angiography. The detection rate of CT angiography in this report was 89%, higher than those of previous reports. Thirteen aneurysms were located at internal carotid-posterior communicating artery (ICPC) junction. 11 at anterior communicating artery (Acom), 7 at middle cerebral artery (MCA). CT angiography showed a false positive findings in 4 cases, which were all located at Acom. Four aneurysms were not detected in CT angiography, which were all located at MCA and were very small (2-3 mm) in diameter. There were no deteriorated cases during and after CT angiography. We suggest that CT angiography is a useful and safe method for predicting the location of not only unruptured but ruptured aneurysms.     

Intracranial bacterial aneurysms--report of two cases with special reference to operative indications

Two cases of intracranial bacterial aneurysms caused by bacterial endocarditis are reported. Case 1 was a 20-year-old male who underwent mitral valve annuloplasty because of mitral regurgitation due to mitral valve prolapse syndrome 3 year prior to this admission. He was referred when a large intracerebral hemorrhage of the right frontal lobe ruptured into the lateral ventricle was seen in computed tomography (CT) scan on admission. An aneurysm at the distal portion of precentral artery of the middle cerebral artery (MCA) was found by right carotid angiography. Emergency evacuation of the hematoma and trapping of the aneurysm were performed. Another three aneurysms, located at the distal portion of contralateral left precentral artery of MCA, the left posterior cerebral artery (PCA) and the right anterior falx artery were found in the subsequent angiogram. The latter two aneurysms developed while receiving antibiotics. The aneurysms of PCA and MCA were trapped surgically. However, the aneurysm of anterior falx artery disappeared spontaneously under antibiotic therapy without surgery. Case 2 was a 21-year-old female who underwent cardiac surgery one month prior to presentation for aortic insufficiency and coarctation of the aorta. She was referred to our clinic because of sudden loss of consciousness, aphasia and right hemiparesis. CT scan and left carotid angiography showed a large hematoma in the left frontal lobe and an aneurysm at the distal portion of the opercular-frontal artery. Emergency ventricular drainage was performed. The operation for evacuation of the hematoma and clipping of aneurysm was performed 10 days later. However, at the operation the aneurysm neck was only partially clipped in order to prevent the obstruction of efferent vessels.(ABSTRACT TRUNCATED AT 250 WORDS)     

Dissecting aneurysms of the anterior cerebral artery and accessory middle cerebral artery. Case report

A 66-year-old woman presented with dissecting aneurysms of the anterior cerebral artery (ACA) and accessory middle cerebral artery (MCA) manifesting as subarachnoid hemorrhage but without radiological evidence of the dissecting aneurysms. Intraoperative observation revealed that the vessel walls were dark purple in color, a typical finding of dissecting aneurysm. The abnormal A1 segment was trapped and the dissecting aneurysm of the accessory MCA was wrapped. In the case of SAH of unknown origin, dissecting aneurysm should always be kept in mind even if the angiogram does not show any abnormal finding. This is the first reported case of dissecting aneurysm of the accessory MCA.     

Intraparenchymal and intrasylvian haematomas secondary to ruptured middle cerebral artery aneurysms: prognostic factors and therapeutic considerations.

The aim of this study was to investigate prognostic factors and the most appropriate treatment for patients with ruptured middle cerebral artery (MCA) aneurysms in relation to haematoma distribution. Ninety-two patients with ruptured MCA aneurysms, who underwent surgery during the last 11 years from 1986 to 1996, were assigned to one of the three groups according to the haematoma distribution. Group A comprised 17 patients who had an intraparenchymal haematoma (IPH) larger than 30 mm (maximum diameter) with or without subarachnoid haemorrhage (SAH), group B comprised 24 patients having a dense intra-Sylvian fissure haematoma (ISH) larger than 30 mm (maximum diameter) and group C consisted of 52 patients having only diffuse SAH without a localized dense haematoma. The clinical course and factors affecting the outcome of the patients in each group were investigated. Patients in groups A and B had a more severe clinical grade on admission than those in group C. As a result, patients in these two groups had a poorer outcome. In group C, independent life was achieved for 98% of the patients. In group A, the clinical grade on admission and the diameter of the haematoma were significantly correlated with outcome. Initial brain damage due to IPHs seemed to be the main cause of disability, while only 7% developed delayed ischaemic neurological deficits (DIND). In group B, 54% of patients suffered from subsequent brain oedema and DIND occurred in 50%. These factors were related to a poor outcome. The MCA aneurysms tend to have localized dense haematomas, as well as diffuse SAH; the former seems to affect more on the course and outcome of the patients. Accurate assessment of the bleeding patterns in patients with ruptured MCA aneurysms will be useful in helping us predict the clinical course and the most appropriate treatment for these individuals.     

Ruptured intracranial dissecting aneurysms: management considerations with a focus on surgical and endovascular techniques to preserve arterial continuity

Background. The present retrospective analysis was undertaken to review an institutional experience with 13 intracranial dissecting aneurysms as source of subarachnoid haemorrhage (SAH) among a total of 585 ruptured intracranial aneurysms. Methods and results. In 6 patients the vertebral artery (VA) was affected, in 2 patients the basilar artery (BA), in 3 the internal carotid (ICA), in 1 the middle cerebral (MCA) and in 1 the postcommunicating (A2) segment of the anterior cerebral artery (ACA). Maintaining arterial patency was aimed at in all patients. Tangential clipping or circumferential wrapping were used as surgical methods. Endovascular stenting and/or coiling was applied in 2 instances. Four of the 6 VA dissecting aneurysms underwent surgical exploration between 1 and 22 days after haemorrhage. Two patients were in WFNS grade V and died subsequently with the aneurysms untreated, one after rehaemorrhage. In the patients with secured VA aneurysms the postoperative course was uncomplicated with the exception of additional caudal cranial nerve injury in 1 instance. Both BA aneurysms were initially treated by endovascular methods. In the first patient incomplete packing with Gugliemi detachable (GDC) coils was achieved. Follow-up angiography 6 months later showed growth and coil compaction and subsequent wrapping with Teflon fibres resulting in angiographic stabilization. The other BA aneurysm was treated by a combination of a coronary stent and GDC coils. The 3 dissecting ICA aneurysms were all explored surgically. In only 1 instance ICA continuity could be preserved by wrapping, in the other 2 cases a major portion of the vessel wall disintegrated upon removal of the surrounding clot. The only ACA dissecting aneurysm, on A2, was successfully treated with a Dacron cuff. In the single patient with a MCA aneurysm, a decision for conservative management was taken, because neither a surgical nor an endovascular solution was seen as a possibility that did not risk occlusion of lenticulostriate branches. The patient suffered a fatal rehaemorrhage 4 weeks later at her home. Conclusions. The reported experience suggests that in Western countries also dissecting aneurysms are an occasional source of SAH. The outcome in our conservatively managed patients confirms the poor prognosis of conservative management. Wrapping and endovascular stent based methods can achieve stabilization of the dissected artery without sacrificing the artery. Results of treatment appear to depend largely on the location of the dissecting aneurysm.     

Saccular aneurysms of the distal anterior cerebral artery

We report a series of 42 consecutive patients with aneurysms of the distal anterior cerebral artery (ACA). Of these, 36 patients had one aneurysm, 5 had two aneurysms, and one had three aneurysms. Thirty patients had a ruptured distal ACA aneurysm; among these patients, the size of the aneurysm was less than 5 mm in diameter in 20, 6 to 10 mm in 7, and larger than 11 mm in 3. Eighteen patients (42.9%) had multiple aneurysms, and distal ACA aneurysms were responsible for a subarachnoid hemorrhage in 10. Thirty-four patients underwent direct surgery, and 30 of these had excellent outcomes 3 months after surgery. The treatment of patients with distal ACA aneurysms is often technically difficult, because of their broad neck configuration and the coexistence of other aneurysms. Nevertheless, the present study emphasizes that distal ACA aneurysms tend to bleed, irrespective of their size, and that excellent outcomes are obtainable by direct surgery.     

Observation of de novo formation and growth of an intracranial aneurysm: a case report

We observed a de novo formation and growth of an aneurysm in a 43-year-old woman who was followed up after treatment of a subarachnoid hemorrhage (SAH). In 2002, the patient, whose mother had a history of SAH, presented with SAH at the age of 36. Three-dimensional computed tomography angiography (3D-CTA) and digital subtraction angiography showed an aneurysm in the right internal carotid-posterior communicating artery. The aneurysm was clipped and postoperative course was uneventful without neurological deficit. The patient was followed up by 3D-CTA and magnetic resonance angiography every 6 months, because of an untreated small aneurysm, 3 mm in diameter, in the left middle cerebral artery (MCA). The MCA aneurysm remained unchanged but a de novo aneurysm, 1.5 mm in diameter, developed in the right anterior cerebral artery (ACA) 6 years after the first surgery. The ACA aneurysm grew to 4 mm in diameter during the following 10 months but the MCA aneurysm remained unchanged. Both aneurysms were clipped in one session. The MCA aneurysm had a smooth wall but the ACA aneurysm had an irregular and thin wall. The postoperative course was uneventful. Young female patients who have developed SAH with familial history, like this case, should receive long-term follow up to check whether a de novo aneurysm has developed.     

Ruptured distal middle cerebral artery aneurysm

OBJECT: Ruptured distal middle cerebral artery (MCA) aneurysms are uncommon, and their clinical and radiological features are poorly understood. To clarify characteristics of these lesions, the authors undertook a retrospective analysis of nine patients with ruptured distal MCA aneurysms. METHODS: The medical records of patients who underwent surgical repair of ruptured intracranial aneurysms between 1988 and 2002 at Shinshu University Hospital and its affiliated hospitals were retrospectively evaluated. The authors found only nine patients with a ruptured distal MCA aneurysm, and their clinical, neuroimaging, and intraoperative findings were evaluated. CONCLUSIONS: This study of nine patients with distal MCA aneurysms is the largest series to date. Eight lesions were saccular aneurysms that were clipped and the remaining one was a mycotic aneurysm that was trapped. Eight of the nine patients suffered cerebral hematomas with subarachnoid hemorrhage. All patients had good outcomes after obliteration of their aneurysm, although their preoperative condition was not good.     

Characteristics and management of ruptured distal middle cerebral artery aneurysms

Summary Objective. Distal middle cerebral artery (dMCA) aneurysms are very rare with a reported frequency of 2–6%. Typically, patients with ruptured distal MCA aneurysms have poor clinical outcomes because often there is both a subarachnoid haemorrhage (SAH) and an intracerebral haematoma (ICH). The goals of this study were to identify the characteristics of the distal MCA aneurysms and evaluate the optimal treatment for a good outcome. Methods. The clinical, neuroradiological and operative records of 8 patients with a ruptured distal MCA aneurysm who underwent surgical management were reviewed retrospectively. The outcomes were presented according to the Glasgow Outcome Scale (GOS). Results. The clinical characteristics of the patients with ruptured dMCA aneurysms included the following: (1) a fusiform appearance in five out of eight (63%) patients. (2) Mean aneurysm size of 9.4 mm (range 2–35 mm). (3) The location being M2 (insular segment) in three, M2-3 junction in three, and M3 (opercular segment) in two patients. (4) Brain CT images revealed both SAH and an ICH in six of eight (75%) patients with the mean size of the ICH being 10 cc (range 5–25 cc). (5) Re-bleeding occurred in four out of eight (50%) of patients. All patients underwent early surgical treatment and the procedures used for surgical repair were, clipping in five patients, trapping in two, and trapping with end-to-end bypass surgery in one patient. Clinical outcomes were poor in two patients (death) due to severe brain swelling. Conclusions. In this study, dMCA aneurysms had a fusiform shape and a high re-bleeding rate; if ruptured, there was generally ICH and SAH. A good clinical outcome was associated with adequate control of brain swelling and early surgery to prevent re-bleeding.     

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.     

Ruptured intracranial aneurysms: an autopsy study of 133 patients

The autopsy findings of 133 patients with ruptured intracranial aneurysms were reviewed: 24 (18%) had multiple aneurysms. Intraventricular hemorrhage was seen in 53 patients (40%), and intracerebral hematoma was seen in 52 (39%). Intraventricular hemorrhage was seen most frequently in patients with anterior communicating artery aneurysms [21 of 40 (53%)]. Intracerebral hematoma occurred most frequently in patients with middle cerebral artery aneurysms [11 of 28 (39%)]. Hemorrhages arising from anterior communicating artery aneurysms had two types of penetration routes into the lateral ventricle. The first was through the inferomedial portion of the frontal lobe, and the second was through the corpus callosum. The second type was poorly visualized in horizontal sections of the brain. Of 40 patients with anterior communicating artery aneurysms, the first type of penetration route was observed in 15, and the second type was found in 3. The second type is rare, and if the hemorrhage is not massive, it may be overlooked in axial computed tomography scans. Of the 109 ruptured aneurysms, 18 (17%) were 4 mm or less in diameter, 50 (46%) were 5-9 mm in diameter, and 41 (38%) were 10 mm or larger in diameter. In the 21 patients with multiple aneurysms, unruptured aneurysms were smaller than ruptured aneurysms in 17 of 27 (63%), equal size in 9 (33%), and larger in 1 (4%). Regarding rerupture, the larger the ruptured aneurysms were, the higher the percentage of rerupture, that is, 11% of 18 ruptured aneurysms of 4 mm or less in diameter, 32% of 50 of 5-9 mm in diameter, and 37% of 41 of 10 mm or larger in diameter had reruptured. It seems that the larger the size of the aneurysm, the higher the risk of rerupture as well as of initial rupture.     

Aneurysms located at the proximal anterior cerebral artery and anterior communicating artery associated with middle cerebral artery aplasia: case report

BACKGROUND: Aneurysms arising from the proximal anterior cerebral artery (ACA) are quite rare. Here, we report upon such a case of aneurysms located at the proximal ACA and anterior communicating artery associated with middle cerebral artery (MCA) aplasia. CASE DESCRIPTION: A 64-year-old woman complained of severe headache. Brain computed tomography scans demonstrated acute subarachnoid hemorrhage. Angiograms showed 2 aneurysms located at the anterior communicating artery and proximal ACA, but did not show an MCA shadow on the lesion side. Instead, multiple collateral vessels ran toward the sylvian fissure and supplied the MCA territory, together with hypertrophied perforating branches. The operative findings confirmed that the cordlike rudimentary MCA had no internal blood flow. The 2 aneurysms were secured by neck clipping. CONCLUSION: The combined effects of these anomalies on the hemodynamic equilibrium of the arteries and the genesis of the aneurysms are noteworthy.