Duplicated Middle Cerebral Artery Aneurysms Treated by Coil Embolization; A Report of Two Cases and Literature Review

BackgroundDuplication of the middle cerebral artery (DMCA) is an anomalous vessel arising from the internal carotid artery (ICA). Aneurysms at the origin of a DMCA have been reported; however, most have been treated with clipping surgery. Here, we describe two cases of aneurysms at the origin of a DMCA treated with coil embolization.Case presentationCase 1: A seventy-three year-old man presented with severe headache and was diagnosed with subarachnoid hemorrhage (SAH). Digital subtraction angiography (DSA) and 3-dimensional (3-D) DSA showed an aneurysm arising from a DMCA. Coil embolization was performed with DMCA patency. The patient had an uneventful postoperative course.Case 1A 44-year-old woman presented with a history of clipping for an IC-anterior choroidal artery (AchA) aneurysm 8 years prior. Magnetic resonance imaging (MRI) showed regrowth of the aneurysm. 3-D DSA showed an IC-DMCA aneurysm located laterally and distal to the AchA. The DMCA arose from the bottom of the aneurysm. Coil embolization was performed without DMCA occlusion and showed no postoperative ischemic changes.ConclusionAn IC-DMCA aneurysm is rare and may be misdiagnosed as an AchA aneurysm. Clinicians should perform a 3D-DSA evaluation if the aneurysm arises from the lateral wall of the IC to obtain a precise diagnosis and to preserve the DMCA during coil embolization.     

Kissing aneurysms of the distal anterior cerebral artery

Kissing aneurysms, a particular type of multiple aneurysm are rare. A kissing aneurysms was identified at the distal anterior cerebral artery (ACA) in a 59-year-old male patient diagnosed with subarachnoid hemorrhage (SAH). The use of three-dimensional intracranial CT angiograms revealed that kissing aneurysms (that is, an aneurysm with a bilateral symmetrical mirror image) were located at the distal ACA and diffuse SAH in basal, sylvian, and interhemispheric cisterns. Both conventional carotid angiograms showed that both distal ACA aneurysms were seen separately on both internal carotid angiograms. Two aneurysms were observed simultaneously on carotid compression of either side. Some particular cautions required in diagnosing and treating kissing aneurysms are discussed, together with a literature review.     

Saccular bilobed aneurysm of an azygos anterior cerebral artery.

An azygos anterior cerebral artery is an anatomical variant in which the anterior communicating artery is absent and both the A1 segments unite to form a single A2 segment of the artery. This anatomical variant may be associated with holoprosencephaly and may predispose to aneurysm formation, however the association of such an anomaly with an aneurysm is rare. When associated with an aneurysm, it poses management difficulties due to the single distal anterior cerebral artery. Most of the reported aneurysms with such an anomaly are saccular and located in the distal part of the artery. We report a patient with a wide neck saccular multilobed aneurysm who presented after a grade 3 subarachnoid haemorrhage. A right pterional craniotomy and clipping of the aneurysm was performed following cerebral angiography. The mechanism of formation and difficulties in management of such an aneurysm is discussed.     

Hydro<Emphasis Type="Italic">Coil</Emphasis> embolization of a ruptured infectious aneurysm in a pediatric patient: case report and review of the literature

Introduction Intracranial infectious aneurysms in the pediatric population are rare. Although surgery has been the traditional treatment of ruptured pediatric infectious aneurysms, endovascular coil embolization has become an attractive alternative due to its low rate of morbidity and mortality. Case report A 9-year-old boy with a significant medical history of aortic valve replacement, antibiotic-treated infective endocarditis, and multiple embolic cerebral infarcts presented with a high-grade intraventricular hemorrhage due to the rupture of a large infectious proximal posterior circulation aneurysm. Computed tomography and cerebral angiogram demonstrated a right crural/ambient cistern hematoma and an associated infectious aneurysm of the right proximal posterior cerebral artery. The ruptured infectious aneurysm was coil-embolized with hydrogel-coated platinum coils without sacrifice of the distal parent artery. The aneurysm was completely occluded, and the patient regained all neurological function. Conclusion Ruptured infectious aneurysms in the pediatric population occur despite aggressive medical therapy. Patients with infective endocarditis and embolic infarcts should be followed closely due to the risk of major hemorrhagic events, including aneurysm rupture. Hybrid coil embolization of ruptured infectious aneurysms with preservation of the distal parent artery is exceedingly rare and effective in the management of ruptured infectious aneurysms in the pediatric population.     

Dissecting aneurysm of distal posterior inferior cerebellar artery--case report and review of the literature

A rare case of dissecting aneurysm of distal posterior inferior cerebellar artery (PICA) is reported. A 51-year-old woman was admitted to our hospital complaining of severe headache and nausea. CT scan revealed subarachnoid hemorrhage which was thicker in the posterior fossa. The vertebral angiography demonstrated an aneurysm on the telovelotonsillar segment (Lister's classification) of the left PICA. On the third day, the left suboccipital craniotomy was performed and the fusiform aneurysm was resected. The postoperative course was uneventful. Histological examination of the resected aneurysm showed a dissection between the ruptured elastic lamina and the tunica media. Dissecting aneurysm of distal PICA is still belong to a rare entity. In all three cases found in the literature, the dissecting aneurysms are sited in the anterior medullary segment of PICA. Probably, this is the first report described a dissecting aneurysm on the more distal part-telovelotonsillar segment of PICA. The clinical features, pathogenesis and treatment of intracranial dissecting aneurysms are briefly discussed with reviewing the literature.     

Ruptured Total Intrameatal Anterior Inferior Cerebellar Artery Aneurysm

Among the distal anterior inferior cerebellar artery (AICA) aneurysms, a unique aneurysm at the meatal loop inside the internal auditory meatus is extremely rare. The authors report a case of surgically treated total intrameatal AICA aneurysm. A 62-year-old female patient presenting with sudden bursting headache and neck pain was transferred to our department. Computed tomography and digital subtraction angiography showed subarachnoid hemorrhage at the basal, prepontine cistern and an aneurysm of the distal anterior inferior cerebellar artery inside the internal auditory meatus. Surgery was performed by retrosigmoid craniotomy with unroofing of the internal auditory meatus. The aneurysm was identified between the seventh and eighth cranial nerve in the meatus and was removed from the canal and clipped with a small straight Sugita clip. After operation the patient experienced transient facial paresis and tinnitus but improved during follow up.     

Aneurysm of the anterior inferior cerebellar artery (AICA) associated with high-flow lesion: report of two cases and review of literature.

OBJECTIVE AND IMPORTANCE: Although aneurysms of the anterior inferior cerebellar artery (AICA) are rare lesions, their occurrence in combination with high-flow lesions in the same arterial territory is even more striking. Two cases of an AICA aneurysm in combination with a high -flow lesion are described. CLINICAL PRESENTATION: In one case, a 52-year-old female presented with cerebellar syndrome as the result of a left-sided cerebellar tumor. Angiography revealed a highly vascularized tumor and a broad-based aneurysm at the offspring of the left AICA. In the second case, a 17-year-old female presented with a right-sided cerebellar hemorrhage. Angiography revealed a large peripheral AICA aneurysm and a distal arteriovenous malformation (AVM) fed by the AICA. INTERVENTION: In the first case, a left lateral suboccipital craniotomy was performed and a highly vascularized tumor was removed. The AICA aneurysm could not be adequately clipped and was subsequently wrapped with muscle and reinforced with fibrin glue. Pathological examination of the tumor revealed a hemangioblastoma. Five years after surgery, the patient experienced a subarachnoid hemorrhage. Subsequent vertebral angiography revealed local enlargement of the known AICA aneurysm just at the superior aspect, but the patient refused further treatment. In the second case, the patient sustained a novel cerebellar rebleed while awaiting surgery. A right-sided lateral retromastoid suboccipital craniotomy was performed and the AICA aneurysm could be successfully clipped. More peripherally, the AVM with two draining veins could be totally removed. Postoperative angiography revealed no residual aneurysm or AVM. CONCLUSION: Several aspects of these cases are discussed, such as the rare occurrence of AICA aneurysm and the contribution of high-flow lesions to the genesis of the AICA aneurysms.     

A giant fusiform basilar aneurysm treated by bilateral vertebral artery occlusion.

OBJECTIVE AND IMPORTANCE: Fusiform aneurysms of the vertebrobasilar arteries that progressively enlarge causing symptomatic brainstem compression are dangerous and their treatment is difficult. A patient with such an aneurysm treated successfully with staged, microsurgical occlusions of the proximal vertebral arteries is described, and the literature pertaining to this rare condition is briefly reviewed. CLINICAL PRESENTATION: A 48-year-old man with a fusiform basilar trunk aneurysm of uncertain etiology presented initially with transient ischemic attacks (TIAs) of the posterior circulation that ceased with anticoagulation. Four years later he presented again with progressive ataxia, dysphagia and dysphonia due to considerable enlargement of the aneurysm causing brainstem compression. INTERVENTION: Staged microsurgical vertebral artery occlusions proximal to the aneurysm were performed. The second (left) vertebral artery was clipped only after the patient passed its temporary occlusion with an endovascular test balloon. The aneurysm subsequently thrombosed, the distal basilar artery kept patent by a single (left) posterior communicating artery. The patient's clinical condition improved markedly over a number of months as the aneurysm mass atrophied. CONCLUSION: Giant vertebrobasilar aneurysms are rare but treacherous lesions, sometimes justifying aggressive management. Carefully selected patients with progressive and severe symptoms due to brainstem compression may tolerate proximal vertebral artery occlusions, provided there is adequate collateral flow to the basilar termination and all of its perforating branches.     

Dissecting aneurysm of the middle cerebral artery associated with subarachnoid haemorrhage

A 73-year-old male with known hypertension presented with subarachnoid haemorrhage due to a ruptured dissecting aneurysm of the middle cerebral artery. Angiography showed a dilatation with proximal and distal narrowing of the right middle cerebral artery. Conservative treatment resulted in almost complete resolution of the angiographic abnormalities 6 months later. Dissecting aneurysms of the middle cerebral artery with haemorrhagic manifestations are extremely rare and are not generally recognized as a cause of subarachnoid haemorrhage. If angiography fails to demonstrate a saccular aneurysm in a patient with subarachnoid haemorrhage, a ruptured dissecting aneurysm may be a possible cause. Repeat angiography should be performed for definitive diagnosis. More knowledge about the natural course is essential before determining whether surgical treatment is always necessary.     

Tratamiento endovascular de un aneurisma «verdadero» de la arteria comunicante posterior

True posterior communicating artery aneurysms originate exclusively from the wall of this artery and should be differentiated from aneurysms of the posterior communicating segment of the distal carotid artery. As these lesions are rare, their anatomical relationships have been poorly described; likewise, reports concerning their endovascular treatment are extremely rare and the technical aspects poorly detailed.A case of a patient with a true aneurysm of the left posterior communicating artery treated by endovascular coiling is presented. A literature review was also conducted to illustrate the anatomical and technical details relevant to achieving its successful treatment.     

Traumatic cerebral aneurysm formation following ventriculoperitoneal shunt insertion

Introduction Iatrogenic intracranial aneurysms are rare in children.Case report A 15-year-old girl presented in coma with a fixed dilated left pupil six weeks following removal of a long-standing left-sided ventriculoperitoneal shunt. Computed tomography (CT) and cerebral angiography revealed a left temporoparietal intracerebral haemorrhage with a fusiform distal middle cerebral artery aneurysm. The patient underwent image-guided localisation of the aneurysm to enable evacuation of the haemorrhage and resection of the fusiform aneurysm.Conclusion A high index of suspicion is required for diagnosis and early treatment to prevent unnecessary morbidity and mortality.     

Glue Embolization of Ruptured Anterior Thalamoperforating Artery Aneurysm in Patient with Both Internal Carotid Arteries Occlusion

Thalamoperforating artery aneurysms are rarely reported in the literature. We report an extremely rare case of ruptured distal anterior thalamoperforating artery aneurysm which was treated by endovascular obliteration in a patient with occlusion of both the internal carotid arteries (ICAs) : A 72-year-old woman presented with severe headache and loss of consciousness. Initial level of consciousness at the time of admission was drowsy and the Glasgow Coma Scale score was 14. Brain computed tomography (CT) scan was performed which revealed intracerebral hemorrhage in right basal ganglia, subarachnoid hemorrhage, and intraventricular hemorrhage. The location of the aneurysm was identified as within the globus pallidus on CT angiogram. Conventional cerebral angiogram demonstrated occlusion of both the ICAs just distal to the fetal type of posterior communicating artery and the aneurysm was arising from right anterior thalamoperforating artery (ATPA). A microcatheter was navigated into ATPA and the ATPA proximal to aneurysm was embolized with 20% glue. Post-procedural ICA angiogram demonstrated no contrast filling of the aneurysm sac. The patient was discharged without any neurologic deficit. Endovascular treatment of ATPA aneurysm is probably a more feasible and safe treatment modality than surgical clipping because of the deep seated location of aneurysm and the possibility of brain retraction injury during surgical operation.     

Bony Protuberances on the Anterior and Posterior Clinoid Processes Lead to Traumatic Internal Carotid Artery Aneurysm Following Craniofacial Injury

Traumatic intracranial aneurysms are rare, comprising 1% or less of all cerebral aneurysms. The majority of these aneurysms arise at the skull base or in the distal anterior and middle cerebral arteries or their branches following direct mural injury or acceleration-induced shearing force. We present a 50-year-old patient in whom subarachnoid hemorrhage (SAH) was developed as a result of traumatic aneurysm rupture after a closed craniofacial injury. Through careful evaluation of the three-dimensional computed tomography and conventional angiographies, the possible mechanism of the traumatic internal carotid artery trunk aneurysm is correlated with a hit injury by the bony protuberances on the anterior and posterior clinoid processes. This traumatic aneurysm was successfully obliterated with clipping and wrapping technique. The possibility of a traumatic intracranial aneurysm should be considered when patient with SAH demonstrates bony protuberances on the clinoid process as a traumatic aneurysm may result from mechanical injury by the sharp bony edges.     

Clinical characteristics of ruptured distal middle cerebral artery aneurysms: Review of the literature

Middle cerebral artery (MCA) aneurysms usually arise at the primary MCA bifurcation or trifurcation. Distal MCA aneurysms are rarely considered as sources of aneurysmal subarachnoid hemorrhage (SAH). It has been reported that ruptured distal MCA aneurysms are associated with head trauma, neoplastic emboli, arterial dissection, or bacterial infection. We experienced five cases of ruptured distal MCA aneurysms and evaluated their clinical characteristics. Retrospective analysis of aneurysmal SAH at Kobayashi Neurosurgical Neurological Hospital was performed from January, 2004 to December, 2014. Clinical characteristics of ruptured distal MCA aneurysms were analyzed using our database. Among 191 aneurysmal SAH patients, there were five ruptured distal MCA aneurysms. All patients did not have any specific medical problems such as infectious disease, head trauma, or cardiac disorders. The incidence of ruptured distal MCA aneurysm was higher than expected and was equivalent to 9.4% of the total ruptured MCA aneurysms. Strong male predominance (80%) and M2–3 junction aneurysm preponderance (80%) were observed. In addition, there were only two patients (40%) with intracerebral hematoma in our study. We reported five cases of ruptured distal MCA aneurysms. Although ruptured distal MCA aneurysms are thought to be rare as sources of aneurysmal SAH, the incidence of ruptured distal MCA aneurysm was 9.4% of all ruptured MCA aneurysms in our study. Ruptured distal MCA aneurysms should be considered as sources of aneurysmal SAH without intracerebral hematoma.     

Distal posterior cerebral artery aneurysm associated with multiple aneurysms

True congenital peripheral aneurysms of the cerebral arteries are rare and may constitute a special entity. We report a rare case of nonmycotic peripheral aneurysm of the posterior cerebral artery (PCA) found in association with aneurysms of distal middle cerebral artery (MCA), junction between basilar artery (BA) and superior cerebellar artery (SCA) and MCA trunk. Our present case was a 37-year-old man with a history of abrupt loss of consciousness. Cerebral angiography revealed a right PCA aneurysm originating at the junction between the trunk of the PCA and the posterior temporal branch, and also aneurysms of the right distal MCA, at the right BA–SCA junction and at the trunk of right MCA just distal to the anterior temporal artery. Distal PCA aneurysm causing subarachnoid hemorrhage was successfully clipped and all the other aneurysms were treated in a one-stage procedure. Pathological examination of the surgically excised distal PCA aneurysmal sac demonstrated no infectious etiology. There have not been any similar cases showing an association of vascular anomalies with distal PCA aneurysm. This is the only reported case with the association of nonmycotic peripheral aneurysms involving the MCA and PCA.     

Multiple Cerebral Aneurysms Associated With Neurofibromatosis Type 1

Neurofibromatosis type 1 (NF1) is a rare disease with an incidence of approximately one in every 3000 births. NF1 is mainly recognized as a tumor suppressor. Vasculopathy in NF1 is well described in the literature, but the association between NF1 and cerebral aneurysm has not been determined. We report a case of a 67-year-old female with NF1 accompanied by 8 cerebral aneurysms. Two of the patient's unruptured aneurysms, the large distal anterior cerebral artery (ACA) aneurysm and anterior communicating artery aneurysm, were initially treated with microsurgical clipping. The peripheral ACA aneurysm gradually increased in size and ruptured after 5 years. Coil embolization was performed for the ruptured aneurysm. Four of the 5 remaining unruptured aneurysms were treated surgically. The patient is currently well, without neurological deficit, and coil embolization is scheduled for the last remaining aneurysm. NF1 is a probable risk factor for multiple cerebral aneurysms due to vessel wall vulnerability. Therapeutic indications for patients with NF1 who show multiple cerebral aneurysms include strict follow-up and aggressive treatment to avoid subarachnoid hemorrhage.     

Distal calcarine fusiform aneurysm: a case report and review of literature

A 50 year old female who was operated for atrial septal defect 8 years back, presented with clinical features suggestive of subarachnoid haemorrhage (grade I, Hunt and Hess). CT scan of brain revealed haemorrhage in all the supratentorial basal cisterns, sylvian cistern and small haematoma in the left occipital lobe. Conventional CT and MR angiography revealed aneurysm in relation to distal part of the calcarine branch of the left posterior cerebral artery (PCA). Left occipital craniotomy in prone position followed by deep dissection in the occipital lobe showed fusiform aneurysm of the distal part of the calcarine branch. PCA aneurysms constitute only 0.2 to 1% of all intracranial aneurysms and among them distal PCA aneurysms are most rare, constituting only 1.3%. They too are mostly seen at the bifurcation of the PCA. The present case however, is unique in the sense that it has developed as a fusiform aneurysm in the distal part of the calcarine branch. To the best of our knowledge this is rare among the rarest.     

A distal anterior cerebral artery aneurysm in infant: disappearance and reappearance of the aneurysm.

The incidence of intracranial aneurysms in childhood is rare, especially in infancy. Spontaneous thrombosis of a cerebral aneurysm in a child is very rare, particularly in a non-giant aneurysm. We report a case of a 1-month-old girl with a distal anterior cerebral artery aneurysm which disappeared spontaneously after subarachnoid hemorrhage and reappeared 6 months later. Surgical resection of the aneurysm was performed and she discharged uneventfully 10 days later. Histological examination revealed an aneurysm with a fibrous muscular layer, absence of the internal elastic lamina and partial hypertrophy of the intimal layer. Though the pathogenesis of this aneurysm is uncertain, two hypotheses are discussed.     

Extracranial to intracranial bypass for the treatment of cerebral aneurysms in the pediatric population

Cerebral aneurysms are rare in the pediatric population, making a definitive treatment algorithm difficult. Microsurgical clipping is the first choice for treatment but is not always feasible, while high recurrence rates and radiation exposure make endovascular options less favorable. Extracranial-intracranial (EC-IC) bypass, though not commonly performed in the pediatric aneurysm population, has been reported in a small number of studies to be both safe and effective for the management of cerebral aneurysms. The authors present the case of a child with a distal middle cerebral artery (MCA) aneurysm in eloquent territory, successfully treated with a superficial temporal artery (STA) to MCA bypass and trapping. A review of the current literature on pediatric EC-IC bypass in the treatment of intracranial aneurysms is presented.     

Distal aneurysm of the rostral duplicate anterior inferior cerebellar artery feeding an associated dural arteriovenous malformation: case report and review of the literature

A rare case of a distal aneurysm of a rostral, duplicate anterior inferior cerebellar artery feeding an associated dural arteriovenous malformation is reported. The patient presented with severe nuchal rigidity after sexual intercourse; no neurological deficit was seen. The aneurysm causing the subarachnoid hemorrhage was wrapped but the arteriovenous malformation was inoperable. An analysis of the literature showed 51 cases of coexisting aneurysms and arteriovenous malformations in the posterior fossa; only three of them had a dural arteriovenous malformation. A 7:3 male predominance was recognized. The mean age at diagnosis was 48.5 years. Ninety-four per cent presented with hemorrhage and 6% with cranial nerve deficit only. The bleeding originated from the aneurysm in 73% and from the arteriovenous malformation in 15%; in 12% the origin of bleeding was not mentioned or could not be identified. Outcome was satisfactory in 76%, poor in 7% and 17% died. Treatment of both lesions should be performed in a one-stage operation if technically feasible. Additionally, radiosurgery to surgically unresectable arteriovenous malformations should be considered in cases where aneurysms are clipped or coiled.