Aneurysm at the origin of the accessory middle cerebral artery

An aneurysm at the junction of the accessory middle cerebral artery and the horizontal portion of the anterior cerebral artery is reported. The importance of this anomalous artery is discussed with regard to the genesis of aneurysms of the anterior cerebral artery.     

The accessory middle cerebral artery (author's transl)]

The accessory middle cerebral artery has rarely been documented. Four cases of the anomalous artery were found in 1240 carotid angiograms, the incidence being estimated to be 0.24 to 0.34%. Ages of the patients were 45, 52, 53, and 56. They were two males and two females. In two patients, the angiography was carried out because of positive neurological signs after head injury, and in the other two, because of cerebrovascular stroke. All the anomalous arteries were found as incidental findings. The angiography was carried out bilaterally in two patients and the anomalous arteries were found only on one side. They arose from the horizontal portion of the anterior cerebral artery and coursed laterally in paralled with the stem of the middle cerebral artery. Two of them gave rise to the perforating arteries into the brain which accompanied those from the middle cerebral artery. These atomalous arteries were identified very easily on an antero-posterior projection of the angiogram. In the most striking patient, the 52-year-old man, a selective angiography for the middle cerebral artery, which did not demonstrate the anterior cerebral artery and its branch, the accessory middle cerebral artery, was carried out and in the light of the findings, the accessory middle cerebral artery could be identified running in elliptic circle just above D1 on the lateral projection of the routine carotid angiogram. All the accessory middle cerebral arteries in our series were not associated with either intracranial aneurysm or anomalies such as agenesis of the corpus callosum and reduplication of the circle of Willis.     

Aneurysms of the proximal anterior cerebral artery

The authors report eight cases of aneurysm of the anterior cerebral artery proximal to the anterior communicating artery (A1 segment). In six of these cases, the aneurysms arose from the proximal anterior cerebral artery at the origin of either a cortical branch (on case), the accessory middle cerebral artery (one case), or a perforating branch (four cases). In another case the aneurysm arose at the proximal end of the fenestration, whereas in the one remaining case no branch was present at the site of the aneurysmal neck.     

Saccular aneurysm of the accessory middle cerebral artery--case report

A 30-year-old man presented with a rare ruptured saccular aneurysm located at the junction of the accessory middle cerebral artery and the horizontal portion (A1 segment) of the anterior cerebral artery. A right frontotemporal craniotomy was performed and the aneurysm was clipped through a transsylvian approach. The postoperative course was uneventful and he was discharged in good condition. The transsylvian approach is the method of choice for such aneurysm.     

Ruptured aneurysm at a duplicated middle cerebral artery with accessory middle cerebral artery

Summary. Although many cerebral vascular anomalies are widely recognized, others are less well known or unclassified. Accessory middle cerebral artery (MCA) and duplicated MCA are among uncommon anomalies. We present a very rare case of subarachnoid haemorrhage due to rupture of a saccular aneurysm arising from a duplicated middle cerebral artery which was associated with an accessory middle cerebral artery.     

Ruptured Aneurysm at the Trunk of the Accessory Middle Cerebral Artery

We present a 32-year-old woman with intracranial haemorrhage due to rupture of a saccular aneurysm arising from the trunk of an accessory middle cerebral artery. This is the first report of an aneurysm arising distally to the anomalous vessel's origin from the A1 segment of the anterior cerebral artery.     

Ruptured anterior cerebral artery aneurysm at the origin of the accessory middle cerebral artery

A 36-year-old female patient was admitted to our hospital with a rare case of aneurysm at the origin of the accessory middle cerebral artery (MCA) manifesting as severe headache and vomiting. Neurological examination did not detect any abnormalities or consciousness disturbance. Computed tomography demonstrated diffuse subarachnoid hemorrhage. Magnetic resonance angiography showed an aneurysm in the horizontal portion of the left anterior cerebral artery (A(1)). Digital subtraction angiography and three-dimensional digital subtraction angiography demonstrated a saccular aneurysm originating at the junction of the left A(1) and accessory MCA. Another accessory MCA originated at the proximal portion of the left A(2) without an aneurysm. Two accessory MCAs were found on the left. Neck clipping was performed via a left pterional approach. One month after admission, she was discharged without neurological deficits.     

A case of accessory middle cerebral artery associated with internal carotid artery aneurysm (author's transl)

A case of accessory middle cerebral artery associated with internal carotid artery aneurysm was reported. A 50-year-old female was admitted to our hospital with complaints of headache, nausea, vomiting and conciousness disturbance. Lumbar puncture showed bloody CSF. Right carotid angiogram revealed saccular aneurysm of the internal carotid-posterior communicating artery and accessory middle cerebral artery originating from the horizontal portion of the right anterior cerebral artery. No other vascular lesion was observed on other angiograms. Operation was performed 2 days after admission. The neck of the aneurysm was clipped. Postoperative aseptic meningitis was cured by frequent lumbar punctures, and her course was uneventful. The etiological hypothesis of these cerebral vascular anomalies was briefly discussed.     

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.     

Accessory middle cerebral artery and duplication of middle cerebral artery--terminology, incidence, vascular etiology, and developmental significance.

A series of 455 bilateral carotid angiographies included 14 accessory middle cerebral arteries (Acc-MCAs) and seven duplication of middle cerebral arteries (Dup-MCAs). The branching patterns of Dup-MCA could be classified as "direct bifurcation" from the internal carotid artery, since most lacked the essential bifurcation or trifurcation at the distal end of the M1 portion. On the other hand, Acc-MCAs are probably residual congenital arteries. These anomalous MCAs were apparently associated with epilepsy. Five Acc-MCAs were associated with anterior communicating artery aneurysm at the origin. In addition, a rare case of Dup-MCA with arteriovenous malformation at its origin was found.     

Ruptured intracranial aneurysm combined with multiple cerebral vessel anomalies; a case report

We report a very rare case of subarachnoid hemorrhage associated with fenestration of the anterior cerebral artery (ACA), the accessory middle cerebral artery (A-MCA) and the duplication of the middle cerebral artery (D-MCA). It seems that this is the first report of these combined intracranial vascular anomalies, although many authors have reported each anomaly in isolation. A 50-year-old male visited a local physician complaining of the sudden onset of a severe pulsating headache. A lumbar puncture showed bloody cerebrospinal fluid, and he was transferred to our institution. An emergency CT scan showed no apparent subarachnoid hemorrhage, but the left internal carotid angiography showed a saccular aneurysm at the origin of the D-MCA. Other anomalies, such as the fenestration of the ACA and the A-MCA, were also apparent during angiography. The ruptured aneurysm was safely clipped on the next day and the patient was discharged with no neurological deficits three weeks after the operation. The incidence of fenestration of the ACA is 0.2% in the angiographic series, and 0.1-7.2% at autopsy. Fenestration of the ACA is thought to be less than that of the vertebral artery. Ever since it was proposed by Teal et al, the term A-MCA has been restricted to an artery that arises from the ACA, and a branch arising from the internal carotid artery has been termed as the D-MCA. These anomalous vessels supply the cortex in the distribution of the middle cerebral artery. The angiographic incidence of A-MCA is about 4%, and six cases of aneurysm located at the origin of the A-MCA have been reported so far.(ABSTRACT TRUNCATED AT 250 WORDS)     

Aneurysm rupture at an anomalous collateral artery that extended from the proximal A2 segment to the middle of the M1 segment, bypassing atresia of the internal carotid artery bifurcation. Case report

The authors report the first known case in which an anomalous collateral artery was found to connect the proximal A2 segment with the middle of the M1 segment. This rarity was associated with atresia of the T-shaped internal carotid artery bifurcation. Two aneurysms had developed on a tortuous and tangled portion of the anomalous artery; one of them had ruptured, producing a subarachnoid hemorrhage and an intracerebral hematoma in the area of the putamen. The aneurysms were clipped and the intracerebral hematoma was removed via an emergency craniotomy. Possible causes of the anomaly and the differences between it and accessory and duplicated middle cerebral arteries are reviewed.     

Angiographic analysis of the middle cerebral artery in cerebral aneurysms--its branching pattern and so-called vascular anomalies

Branching patterns of middle cerebral artery (MCA) were angiographically analyzed in 704 cases with cerebral aneurysms. The mean age was 53 years old and the men-to-women ratio was 1.1. In addition, 13 vascular anomalies of MCA were reported and their correlation with the occurrence of cerebral aneurysm was studied. Results: MCA branching patterns were classified in 6 types. Each type was further studied by dividing into 2 subgroups, namely one with MCA aneurysms at their side and the other without MCA aneurysms. There were no differences statistically between each two groups. Vascular anomalies were consisted of 5 duplications of MCA, 4 fenestrations, 3 accessories and one case of combination of duplication and accessory in the same side. Duplications and accessories did not have any evidence of developing aneurysm more frequently at their bifurcation than any one of normal MCA branching patterns. So we concluded that duplications and accessories should be thought to have similar meanings with the ordinary branching patterns of MCA in the occurrence of aneurysms. A postmortem case of accessory MCA without aneurysm revealed that the origin of the anomaly was pathologically normal. We suggested that the origin of accessory MCA could both be an enlarged Heubner artery and a rare branching pattern of MCA. The fenestration should be a true anomaly but at this point we do not have any suggestive clue for that. Finally, we thought that the combination of duplication and accessory in a single MCA was very rare morphologically, and worthwhile to report.     

Ruptured aneurysm at the origin of the median artery of the corpus callosum associated with accessory middle cerebral artery--case report

A 62-year-old male presented with ruptured anterior communicating artery (ACoA) aneurysm manifesting as severe headache associated with the rare combination of median artery of the corpus callosum (MACC) and accessory middle cerebral artery (MCA). Computed tomography demonstrated diffuse subarachnoid hemorrhage. Left carotid angiography demonstrated an anomalous vessel originating from the ACoA complex and passing forward in the interhemispheric fissure between the two companion A2 segments. This vessel was identified as the MACC. Another anomalous vessel originated from the left A1-A2 segment and passed into the sylvian fissure. This vessel was identified as the accessory MCA. Left frontotemporal craniotomy was performed to clip the neck of the aneurysm. After identifying both A1 and A2 segments, accessory MCA, and the MACC, the aneurysm neck was occluded successfully. The ACoA complex is one of the most frequent sites of vascular anomalies. Preoperative and intraoperative care is required to identify the presence of anomalies of the ACoA complex prior to clip placement, to avoid accidental damage or clipping, which may result in severe neurological deficits.     

The usefulness of 3D-CTA for the diagnosis of a ruptured aneurysm at the origin of the duplicated middle cerebral artery: case report

Duplication of the middle cerebral artery is known as a rare anomalous vessel arising from the internal carotid artery and an aneurysm at the origin of the duplicated middle cerebral artery is very rare. We presented a case of ruptured aneurysm at the origin of the duplicated middle cerebral artery and discussed the usefulness of 3D-CTA (three-dimensional computed tomographic angiography) for its diagnosis. A 34-year-old female suffered from severe headache and was admitted to our hospital. CT scan revealed diffuse subarachnoid hemorrhage and angiography revealed duplication of the right middle cerebral artery and dilatation at its origin. We could not identify it as an aneurysm by angiography, so we performed 3D-CTA. 3D-CTA was able to demonstrate clearly the aneurysm at the origin of the duplicated middle cerebral artery and we performed neck clipping of the ruptured aneurysm. To our knowledge, previously there have been only 14 cases which reported such an aneurysm at the origin of a duplicated middle cerebral artery. We reviewed the 15 cases including ours and found that, in 4 cases, the aneurysm could not be detected by the initial angiography. We suspected that most of these aneurysms were small, so the detection of the aneurysms by angiography was difficult. We conclude that 3D-CTA is useful for diagnosing aneurysms at the origin of the duplicated middle cerebral artery even when thy can't be detected by angiography.     

Comparative study of retrograde and selective cerebral perfusion with transcranial Doppler

BACKGROUND: Retrograde cerebral perfusion (RCP) is a simple technique and is expected to provide cerebral protection. However, its optimum management and limitations remain unclear. Transcranial Doppler has been used to monitor cerebral perfusion. Using this Doppler technique, we compared cerebral blood flow for RCP with that for selective cerebral perfusion. METHODS: Thirty-two consecutive patients underwent elective surgical repair of an aortic aneurysm involving the aortic arch at Kyushu University Hospital. Retrograde cerebral perfusion was used in 15 patients and selective cerebral perfusion, in 17 patients. Continuous measurement of middle cerebral artery blood flow velocities was performed by transcranial Doppler technique. RESULTS: Retrograde middle cerebral artery blood flow velocities during RCP could be measured in only 3 patients, whereas middle cerebral artery blood flow velocities during selective cerebral perfusion could be measured in all but 1 woman. The increase in middle cerebral artery blood flow velocities after RCP was significantly greater than that after selective cerebral perfusion. CONCLUSIONS: The measurement of middle cerebral artery blood flow velocities with transcranial Doppler technique is practicable during selective cerebral perfusion but difficult during RCP. The increase in middle cerebral artery blood flow velocities after RCP indicates reactive hyperemia and reflects the critical decrease in cerebral blood flow during this type of perfusion.     

Spontaneous middle cerebral artery occlusion with moyamoya-like vessels associated with contralateral middle cerebral artery aneurysm; a case report]

A case of spontaneous middle cerebral artery occlusion with moyamoya-like vessels associated with contralateral middle cerebral artery aneurysm is reported. A 23-year-old male was admitted to our hospital with complaints of severe headache and vomiting. On admission CT scan demonstrated subarachnoid hemorrhage with high density in the left Sylvian fissure and suggested a ruptured left middle cerebral artery aneurysm. Carotid angiograms demonstrated a left middle cerebral artery aneurysm and an occlusion of the right middle cerebral artery at its origin with moyamoya-like vessels. There was no occlusion or stenosis in the bilateral intracranial internal carotid arteries. Furthermore, bilateral vertebral angiograms were also normal. The aneurysm was successfully clipped. The postoperative course was uneventful and the patient was discharged with no neurological deficit. So far as we could ascertain, there have been only 21 cases reported previously of spontaneous middle cerebral artery stenosis or occlusion with moyamoya-like vessels. According to angiographic studies and transcranial Doppler ultrasound findings, we are more inclined to believe that hemodynamic changes secondary to arterial occlusion lead to the formation and growth of aneurysms of the contralateral middle cerebral artery.     

Two cases of distal anterior cerebral artery aneurysm associated with accessory anterior cerebral artery

An accessory anterior cerebral artery (accessory ACA) is a rare anomalous vessel arising from the anterior communicating artery as a median artery of triplicated ACA. It is considered a large median artery of the corpus callosum and distributes to one or both hemispheres. The cases of an accessory ACA aneurysm are extremely rare; however, we experienced two cases of unruptured aneurysm growing at the distal portion of an accessory ACA. Two females, aged 66 and 67 years, respectively, separately consulted our hospital as a result of chronic headaches. Brain MR angiography and following DSA in the first patient demonstrated a triplicated ACA and an aneurysm located just above the corpus callosum growing from the distal portion of the accessory ACA. MRI and MR angiography in the second patient depicted a triplicated ACA and an aneurysm from the accessory ACA as with the first case. Neck clipping of the aneurysm was performed using an interhemispheric approach in both cases. These aneurysms appeared to present the same intraoperative findings as other unruptured aneurysms growing at the usual positions.     

Giant pediatric aneurysm treated with ligation of the middle cerebral artery with the Drake tourniquet and extracranial-intracranial bypass

Saccular intracranial aneurysms occur infrequently in children, and the incidence of pediatric giant aneurysms is statistically in the same proportion as in adults. The management of these giant aneurysms can be treacherous. This paper presents a case of a 9-year-old boy with a giant aneurysm of the right middle cerebral artery that was successfully managed by ligation of the middle cerebral artery using a Drake tourniquet with the patient awake and by augmentation of the middle cerebral artery circulation with superficial temporal artery-middle cerebral artery anastomosis without excision of the lesion.     

The Pruitt-Inahara shunt maintains mean middle cerebral artery velocities within 10% of preoperative values during carotid endarterectomy

OBJECTIVE: The purpose of this study was to assess the ability of the Pruitt-Inahara shunt to maintain adequate middle cerebral artery velocities during carotid endarterectomy.Study Design: Prospectively collected data recorded during 548 carotid endarterectomies performed at a single university hospital were analyzed to look at changes in cerebral blood flow velocities at different stages during the procedure. Parallel data relating to blood pressure and end-tidal carbon dioxide were also examined. RESULTS: During the first carotid artery cross clamp, middle cerebral artery velocity fell by 42%. A total of 169 patients (31%) had velocities that fell below 15 cm/s (electrical activity in the brain becomes altered below this level). After shunt insertion, only 2% of patients had middle cerebral artery velocities less than 15 cm/s. In only one patient was the velocity less than 10 cm/s. Increased systolic or diastolic blood pressure raised flow through the shunt significantly (P =.001). When two criteria used for selective shunt use were compared, only a moderate correlation was found between absolute middle cerebral artery velocity after carotid cross clamping and percentage change in middle cerebral artery velocity relative to preclamp values. CONCLUSIONS: The Pruitt-Inahara shunt is able to maintain adequate middle cerebral artery velocity in 98% of patients undergoing carotid endarterectomy. Alterations in blood pressure can significantly affect flow through the shunt.