Intracranial aneurysms associated with moyamoya disease

A Ruptured Aneurysm of the Transdural Anastomotic Artery Occurring at the Temporal Base in Moyamoya Disease: Case Report and Literature Review

A 24-year-old woman with hemorrhagic onset moyamoya disease received bilateral indirect bypass surgery 11 years ago. She presented with a life-threatening atraumatic acute right subdural hematoma with temporal lobe intracerebral hemorrhage due to a transdural anastomosis (TDA) aneurysm rupture. We reviewed six cases of rare TDA aneurysms, all of which occurred around the temporal base. TDA aneurysms may occur near the main trunk of the middle meningeal artery (MMA) where hemodynamic stress is high. Therefore, we must pay attention to skull base aneurysms that form near the MMA; otherwise, the prognosis would be poor if such an aneurysm ruptured.

Radiological Features and Management of Intracranial Aneurysms Associated With Moyamoya Disease: A Case Series of Single-Center Experience

Background Moyamoya disease (MMD) can be a major cause of hemorrhagic stroke. Though extensive angiographic studies have been undertaken, the understanding of the association between aneurysms and MMD remains unanswered. In this study, we explore the association of the aneurysm with MMD and its management. We have also reviewed such associations described in the literature and how the present cases differ from those previously described. Materials and methods The clinical and radiologic data of moyamoya disease cases were accessed from medical and radiological records between January 2010 and July 2017. Two neuroradiologists independently analyzed the data and imaging details. Results Out of 103 patients with MMD, eight patients (7.77%) had associated intracranial aneurysms with eleven aneurysms. Out of the 11 aneurysms, five were the tip of the basilar artery aneurysms and were the most common location for aneurysm (45.5%), followed by lenticulostriate artery, PCA perforator, and distal ACA (DACA) in the P1 PCA, P2 PCA, and P3 PCA artery aneurysms. Out of eight patients, five (62.5%) had a hemorrhage on a non-contrast computed tomography (NCCT) scan of the brain, whereas three (37.5%) had an ischemic presentation. Out of 11 aneurysms, seven aneurysms, including three basilar tip aneurysms (unruptured) and one PCA perforator (ruptured), and three saccular PCA (P1, P2, and P3) (ruptured) were treated by endovascular coiling. Follow-up angiography showed stable aneurysmal occlusion except in one basilar tip, where recurrence was observed. Conclusions MMD-intracranial aneurysm is commonly observed in patients with intracranial hemorrhage and carries a higher risk of rupture. Therefore, identification of the aneurysm is essential for management. Endovascular treatment, either with coil or glue embolization, can be a safe and effective treatment method for such aneurysms with long-term good results.

Spontaneous Middle Meningeal Artery Aneurysms: A Case Report and Review of the Literature

Most reported aneurysms concerning the middle meningeal artery (MMA) are pseudoaneurysms; however, there have been rare reports of non-traumatic MMA aneurysms in the literature. In this paper, we present the case of a 70-year-old female with a true 5-mm aneurysm in the anterior division of the left MMA that was causing erosion through the left temporal bone and was successfully treated with coil embolization. We also present a comprehensive literature review of non-traumatic MMA aneurysms reported since 1930. These aneurysms are associated with conditions such as hypertension, Paget's disease, and intracranial meningiomas and result from flow dynamics disturbances. Treatment involves both endovascular treatment and open surgery, while rupture, especially in the elderly, results in high disability, underscoring the importance of timely intervention upon identification.

Transdural Anastomotic Aneurysm in Association with Moyamoya Disease: A Rare and Troublesome Neurosurgical Entity

Moyamoya disease (MMD) is an idiopathic progressive steno-occlusive disease in the internal carotid artery (ICA) bifurcation. In rare circumstances, transdural anastomotic aneurysm (TAA) could develop during the progression of MMD. We present an illustrative case of TAA in association with MMD. To further explore this rare entity, a comprehensive literature review was also conducted. Our illustrative patient experienced spontaneous remission of the aneurysm during follow-up. By literature review, 12 patients with 13 TAAs, including our case, were identified. The patients aged from 10 to 74 years (46.3 ± 17.4). Eleven (92%) of the patients presented with intracranial hemorrhage, and 1 TAA (8%) was incidentally found. The responsible transdural collaterals were from the middle meningeal artery, occipital artery, internal maxillary artery, and ophthalmic artery in 8 (66.7%), 2 (16.7%), 1 (8%), and 2 (17%) patients, respectively. The anastomosed cerebral arteries were middle cerebral artery, anterior cerebral artery, posterior cerebral artery, and ICA in 5 (42%), 3 (25%), 3 (25%), and 1 (8%) patient, respectively. Eight (67%) patients underwent open surgeries. Two (17%) patients underwent transarterial embolization (TAE) only. Two (17%) patients experienced spontaneous remission of the aneurysm. Seven (58%) patients died or had neurologic deficits. TAAs rarely occur in the progression of MMD, which often presents with intracranial bleeding. Invasive management through open surgery or endovascular treatment is warranted to prevent catastrophic rebleeding. As some individuals might experience spontaneous aneurysm remission, conservative treatment and close imaging follow-up could be considered as an alternative when invasive treatment is risky.

Clinical Features and Outcomes of Intracranial Aneurysm Associated with Moyamoya Disease

Background and Purpose

Moyamoya disease (MMD) is a rare form of intracranial stenoocclusive disease that can be associated with intracranial aneurysms. We evaluated the clinical features and outcomes of MMD-associated aneurysms while focusing on their locations.

Methods

Between January 1998 and December 2018 there were 1,302 adult and pediatric patients diagnosed as MMD at a single institution. These patients included 38 with 44 MMD-associated aneurysms. The MMD-associated aneurysms were classified into two groups based on their locations: major-artery aneurysms and non-major-artery aneurysms. The clinical and radiological data for patients with MMD-associated aneurysms were reviewed retrospectively.

Results

The 44 MMD-associated aneurysms comprised 28 in major arteries and 16 in nonmajor arteries. All of the major-artery aneurysms were initially unruptured lesions, and follow-up angiography showed that 23 (82.1%) had an improved or stable status and 5 (17.9%) had a worse status. The non-major-artery aneurysms comprised 10 ruptured and 6 unruptured lesions, and follow-up angiography showed that 11 (68.8%) had improved or were stable and 5 (31.2%) had worsened. At the latest follow-up, there were four cases of unfavorable outcome: two initial hemorrhagic insults, one treatment-related morbidity, and one repeated-hemorrhage case.

Conclusions

MMD-associated aneurysms occurred in 3.3% of the MMD cohort in this study, of which 63.6% were major-artery aneurysms and 36.4% were non-major-artery aneurysms. The major-artery group included 17.9% that became angiographically worse, while 31.2% were growing or hemorrhaging in the non-major-artery group.

Location-based treatment of intracranial aneurysms in moyamoya disease: a systematic review and descriptive analysis

We conducted a systematic review of the literature to evaluate the efficacy of various treatment modalities for intracranial aneurysms (IA) in patients with moyamoya disease (MMD) based on anatomical location of IA. A comprehensive review of studies documenting single cases or series of MMD patients with concomitant IA was conducted. Aneurysms were classified into two primary anatomical categories: those of the Circle of Willis (CoW) and those of peripheral "moyamoya" collateral vessels. Conservative, endovascular, and open surgical treatment modalities and their outcomes between each anatomical subgroup were descriptively compared. A total of 124 studies consisting of 275 patients with 313 IA were included. Of all IA, 59.6% were located on CoW vessels, 33.7% on peripheral vessels, and 6.7% in "other" locations. Of all CoW IA, 87.2% treated with endovascular techniques had no or minimal deficit at follow-up as compared with 56.7% of those treated with open surgery. Ninety-five percent of patients with peripheral aneurysms treated with endovascular therapy had no or minimal deficit, in contrast to open surgery (69.6%). Of peripheral IA treated conservatively with or without revascularization, 65.7% had spontaneous resolution as compared with 12.0% IA of the CoW. Our results support the use of endovascular techniques for direct treatment of both CoW and peripheral IA. Aneurysms of peripheral vessels respond well to indirect treatment through surgical revascularization as opposed to CoW aneurysms. The quality of evidence is limited due to heterogeneity of included studies and IA management in MMD patients should be considered in a case-specific manne.

Posttraumatic Middle Meningeal Artery Pseudoaneurysm: Case Report and Review of the Literature

BACKGROUND

Intracranial pseudoaneurysm is a rare entity, with few cases described in the literature, and is mostly associated with a history of traumatic brain injury. Traumatic aneurysms comprise <1% of all intracranial aneurysms. In particular, middle meningeal artery (MMA) aneurysms are uncommon and usually caused by a skull fracture in the temporal region. About 40 traumatic MMA aneurysms are reported in the literature, and only 28 nontraumatic aneurysms are reported, usually related to high-flow conditions. The behavior of these aneurysms is largely unknown: both spontaneous resolution and aneurysm growth, leading to subsequent rupture, have been reported. Surgical and endovascular management are feasible for MMA aneurysms; however, the criterion standard treatment is not defined.

CASE DESCRIPTION

We report the case of a traumatic pseudoaneurysm of the right MMA treated with an endovascular approach and provide a review of the literature.

CONCLUSIONS

Aneurysms of the MMA are a rare entity that must be taken into account in the setting of a traumatic brain injury or predisposing factors. The diagnosis and aggressive treatment are mandatory, preventing the devastating consequences of their rupture. Endovascular and surgical techniques are well defined and available, even though there is not a demonstrated superiority in any of them.

Rupture of a Middle Meningeal Artery Pseudoaneurysm in Moyamoya Syndrome Related with Tuberculous Meningitis

We report a rare case of a patient with Moyamoya syndrome who presented with intracerebral hemorrhage resulting from rupture of a middle meningeal artery pseudoaneurysm. This 38-year-old woman was unconscious and hemiplegic when she was admitted to our hospital. The patient had mental retardation as a result of tuberculous meningitis infection at the age of one year. On radiologic examination, she had intracerebral hemorrhage in the right temporo-parietal lobe and an aneurysm in the middle meningeal artery with right internal carotid artery occlusion. The patient underwent surgical treatment for the hemorrhage and aneurysm. The radiologic data, intraoperative findings, and pathology were consistent with a diagnosis of pseudoaneurysm. In the current report, we describe a rare case of a patient with a history of tuberculous meningitis who developed Moyamoya syndrome and pseudoaneurysm, which resulted in a ruptured middle meningeal artery pseudoaneurysm and brain hemorrhage.

Embolization of a peripheral cerebral aneurysm associated with intracranial major artery occlusion through a transdural anastomotic artery: Case report

A peripheral cerebral aneurysm is known to develop at collateral vessels as a result of hemodynamic stress by the occlusion of the intracranial major arteries. We report a case of successful embolization of a ruptured aneurysm through a transdural anastomotic artery. The aneurysm formed at the developed collateral vessel from the meningeal branch of the occipital artery (OA) to the posterior pericallosal artery. A 59-year-old man presented with acute-onset headache, and computed tomography revealed subarachnoid hemorrhage and intracerebral hemorrhage at the splenium of the corpus callosum with intraventricular hemorrhage. Digital subtraction angiography demonstrated a ruptured aneurysm located at a transdural anastomotic artery from the right OA to the posterior pericallosal artery. The patient underwent endovascular treatment for the aneurysm through the transdural anastomotic artery with a coil and n-butyl-2-cyanoacrylate. Because it was impossible to navigate a microcatheter to the aneurysm through the right anterior cerebral artery because of the occlusion of its proximal portion, it was advanced through the transdural anastomosis from the right OA. The aneurysm was completely occluded without complications. Endovascular embolization is a useful treatment option for a peripheral cerebral aneurysm developed at a collateral vessel with intracranial major artery occlusion.

Embolization with NBCA for Ruptured Aneurysm Located in the Moyamoya-like Collateral Network Associated with Isolated Middle Cerebral Artery Occlusion

Collateral vessel formation in moyamoya disease is a well-described phenomenon. However, the occurrence of unusual anastomosis pattern (moyamoya-like) associated with isolated middle cerebral artery (MCA) stenosis or occlusion has been reported very rarely and is not well known the relationship with aneurysm. We report a case of ruptured aneurysm treated with N-butyl cyanoacrylate (NBCA) located in moyamoya like collateral network with isolated MCA occlusion.

Ruptured choroidal artery aneurysms in patients with moyamoya disease: Two case series and review of the literatures

Distal peripheral artery aneurysms in moyamoya disease (MMD) remain difficult to treat given their deep location, small size, and fragility. Here, we report two cases of choroidal artery aneurysms associated with MMD who were treated through direct clipping and coil embolization. Timing of aneurysm formation remains unclear, however, annual follow-up DSA for surveillance of hemodynamic status is necessary and prompt treatment of aneurysm should be performed when diagnosed. Moreover, choroidal artery aneurysms may benefit from endovascular coil embolization due to their characteristics.

Onyx embolization of an intraosseous pseudoaneurysm of the middle meningeal artery in a patient with meningiomatosis, McCune-Albright syndrome, and gray platelet syndrome

A 13-year-old boy with meningiomatosis, McCune-Albright syndrome, and gray platelet syndrome presented with an enlarging "lump" on his right forehead. A head CT scan revealed a polyostotic fibrous dysplasia involving the entire skull. A 3.4-cm right frontal osseous cavity and an overlying right forehead subcutaneous soft-tissue mass were seen, measuring 5.2 cm in diameter and 1.6 cm thick. Ultrasound of the cavity and overlying mass showed swirling of blood and an arterialized waveform. MRI revealed an en plaque meningioma underlying the cavity. An intraosseous pseudoaneurysm fed by 3 distal anterior division branches of the right middle meningeal artery (MMA) with contrast extravasation was found on angiography. Two MMA feeders were embolized with Onyx, with anterograde filling of the intraosseous cavity with Onyx. A small pocket of residual intracavity contrast filling postembolization from a smaller third MMA feeder eventually thrombosed and the forehead lump regressed.

Onyx embolization of a ruptured aneurysm in a patient with moyamoya disease

We report a woman who presented with an intraparenchymal hemorrhage. Her cerebral angiogram showed a middle cerebral artery (MCA) M1 occlusion with multiple collaterals supplying the distal MCA territory, compatible with moyamoya disease. Also, an associated 8 mm dysplastic distal aneurysm fed by a left-sided P2 perforator was seen, collateral from the posterior cerebral artery. The aneurysm was successfully occluded with Onyx (ev3 Endovascular, Plymouth, MN, USA) embolization. The woman had an uneventful postoperative course. Aneurysm formation in patients with moyamoya disease represents a major hemorrhagic risk. Several treatment strategies exist including endovascular and surgical approaches. Patients with moyamoya disease who present with aneurysmal intracerebral hemorrhage should be treated to prevent rebleeding. Onyx embolization can be an effective treatment of aneurysms that are associated with moyamoya disease and would otherwise be difficult to treat surgically.

Resolution of bilateral moyamoya associated collateral vessel aneurysms: Rationale for endovascular versus surgical intervention

BACKGROUND

Management of aneurysms associated with deep collateral vessels in moyamoya disease is challenging both from an endovascular and a surgical standpoint. Difficulties with access or localization, and compromise of the collateral circulation with subsequent ischemia are the primary concerns, making direct obliteration potentially unfeasible or risky. Alternatively, superficial temporal artery-middle cerebral artery bypass is another potential strategy for resolution of these aneurysms.

CASE DESCRIPTION

Presented are the findings and management for a patient with moyamoya disease and bilateral deep collateral vessel aneurysms, successfully treated with endovascular obliteration following a right-sided hemorrhage and subsequently with bypass for an unruptured but growing contralateral aneurysm.

CONCLUSIONS

A rationale and approach to management is outlined, as derived from review of the current literature and the illustrative case with bilateral collateral vessel aneurysms.

Incidental major artery aneurysms in patients with non-hemorrhagic moyamoya disease

BACKGROUND

Major artery aneurysms may be found incidentally while evaluating moyamoya disease (MMD). The purpose of this study was to delineate the prevalence and characteristics of these uncommon aneurysms with a brief mention of their management and outcomes.

METHODS

We conducted a retrospective review of 249 adult patients who were diagnosed with non-hemorrhagic MMD. Cerebral angiograms obtained at the time of initial diagnosis were carefully reviewed to identify incidental aneurysms located on a major intracranial artery or near its tributaries. Aneurysms originating from distal peripheral arteries or moyamoya vessels were ineligible for this study.

RESULTS

Nine patients (3.6%) were found to have 13 major artery aneurysms, 7 (54%) of which were located in the posterior circulation, especially in older patients with bilateral MMD. The sizes of all aneurysms were less than 10 mm. Surgical clipping was performed on two aneurysms, and endovascular coiling on six (five posterior circulation aneurysms). Ischemic complications occurred in two patients after clipping of an anterior communicating artery aneurysm and in one patient after the second coiling of a recanalized basilar tip aneurysm.

CONCLUSIONS

Incidental major artery aneurysms can be found in 3.6% of adult patients with non-hemorrhagic MMD, an observed frequency that increases with age. About half of these aneurysms are located in the posterior circulation, particularly in older patients with bilateral MMD. Considering the risks of treatment-related complications, more information about the natural course of these aneurysms is needed to design proper management strategies both for the aneurysms and MMD.

Repeated rupture of a middle meningeal artery aneurysm in moyamoya disease. Case report

A case of moyamoya disease associated with subarachnoid hemorrhage and intracerebral hematoma resulting from repeated rupture of a middle meningeal artery aneurysm is reported. The aneurysm was progressively enlarged over a period of 1 month and was treated with middle meningeal artery embolization. The treatment method is discussed.

Endovascular treatment of intracranial aneurysms associated with moyamoya disease or moyamoya syndrome

Direct surgical clipping proves to be difficult and dangerous for intracranial aneurysms associated with moyamoya disease (MMD) or moyamoya syndrome (MMS). This study presents our clinical experience of endovascular embolization of intracranial aneurysms associated with these diseases. A total of 13 cases of intracranial aneurysms associated with MMD or MMS were treated by endovascular embolization between January 2001 and January 2009. Patients were divided into two groups: a saccular aneurysm group (n=10) and a pseudoaneurysm group (n=3). Different endovascular therapeutic strategies were employed for each type of case. Of the 13 cases, 11 received successful endovascular embolization and had an uneventful postoperative course during one to two years of follow-up. However, endovascular embolization failed in the other two cases, of whom one died from rebleeding after the five-month follow-up, while the other was conservatively treated and experienced no rebleeding during the two-year follow-up. A favorable prognosis may be secured through careful selection of endovascular treatment regimens for patients with intracranial aneurysms associated with MMD or MMS according to the site of intracranial aneurysms.

Disappearance of a middle cerebral artery aneurysm associated with Moyamoya syndrome after revascularization in a child: case report

INTRODUCTION

Pediatric Moyamoya disease is rarely associated with intracranial aneurysms. We report a case of a 7-year-old girl with an antecedent of persistent craniopharyngeal canal, who presented with a history of choreiform movements.

MATERIALS AND METHODS

A Moyamoya disease was found with an unruptured left middle cerebral artery aneurysm on her first angiography. Conservative treatment was chosen for the aneurysm and she underwent indirect revascularization by encephalosynangiosis using the multiple bur-hole technique for her Moyamoya disease. Abnormal movements were improved. Control angiogram at 6 months showed development of intracranial-extracranial anastomoses with complete resolution of the aneurysm. Aneuryms including the major arteries of the basal arterial circle occur as a by-product of the high velocity and blood flow secondary to the arterial stenosis. Blood flow modification after revascularization often lead to spontaneous regression and disappearance of these aneurysms.

CONCLUSION

Therefore, a conservative treatment of these proximal aneurysms must be chosen after encephalosynangiosis.

Pathological and immunohistochemical findings of an autopsy case of adult moyamoya disease

Moyamoya disease is vaso-occlusive disease involving the arteries of the circle of Willis that is accompanied by a compensatory recruitment of a vascular network. The pathological and immunohistochemical findings of an autopsy case of hemorrhagic moyamoya disease in a 69-year-old woman are described in the present report. The autopsy findings of the brain revealed cerebral and intraventricular hemorrhage with edema. The left anterior cerebral artery, bilateral middle cerebral arteries and left posterior cerebral artery were marked narrowing, and the other arteries revealed mild narrowing. Microscopically, the arteries of the circle of Willis showed narrowed lumen, fibrocellular intimal thickening, marked tortuousness of internal elastic lamina and attenuation of media. The thickened intima was composed of smooth muscle cells. The vessels with dilated or irregular-shaped lumen suggested abnormal vascular networks demonstrated by angiography. In this case, no correlation between the abnormal vascular network and expression of VEGF or VEGF receptor was disclosed. It was hypothesized that abnormal vascular networks might be composed of collateral vessels in relation to various pathological changes of the arteries, such as occlusion and stenosis, and intracranial hemorrhage in patients with moyamoya disease might occur as a result of rupture of arteries including abnormal vascular networks.

Aneurysms of the Posterior Cerebral Artery: Retrospective Review of Surgical Treatment

A series of 10 cases of posterior cerebral artery (PCA) aneurysms were retrospectively reviewed. There were five men and five women aged 38 to 68 years (mean 57.5 years). Seven patients presented with subarachnoid hemorrhage. Two aneurysms were found incidentally during clinical examination for stroke. One aneurysm was associated with moyamoya disease. All aneurysms were saccular. The aneurysms arose from the P1 segment in three patients, the P1/P2 junction in three patients, the P2 segment in three patients, and the P3 segment in one patient. Two patients died before operation and one patient refused surgery. Aneurysmal clipping was performed for seven patients. All aneurysms except the P2 and the P3 aneurysms were treated via the pterional approach. Four patients had excellent outcome, but one patient with a P3 aneurysm developed homonymous hemianopsia due to thrombosis of the parent vessel and another patient with a P2 aneurysm had moderate disability from the initial insult. Coil embolization has been indicated as the first choice of therapy, but PCA aneurysms are good candidates for direct clipping.

Bypass combined with embolization via a venous graft in a patient with a giant aneurysm in the posterior communicating artery and bilateral idiopathic occlusion of the internal carotid artery in the neck

The authors describe the case of a patient with a symptomatic giant aneurysm of the posterior communicating artery (PCoA) associated with bilateral idiopathic occlusion of the internal carotid artery (ICA). The presence of severe tortuosity of the vertebral arteries (VAs), both at their origin from the subclavian artery and at the level of the third segment, impeded navigation of the catheter for embolization of the aneurysm with Guglielmi detachable coils (GDCs). A direct surgical approach was considered to be a high-risk procedure because of the bilateral occlusion of the ICAs and the size of the aneurysm. The following therapeutic strategy was therefore adopted: 1) balloon occlusion test of the left VA; 2) vertebro-vertebral bypass with saphenous vein graft to provide a pathway for subsequent embolization; 3) ICA-left middle cerebral artery bypass to ensure blood flow in the event that embolization resulted in closure of the PCoA; and 4) GDC embolization of the aneurysm via the posterior circulation graft to ensure complete exclusion of the lesion from the arterial circulation and preservation of the PCoA. At 3-month follow-up review the patient did not present with any neurological deficits; at 1-year control examination, magnetic resonance (MR) imaging and MR angiography both confirmed complete exclusion of the aneurysm and patency of the two bypasses.

Intraaneurysmal embolization of an unruptured basilar tip aneurysm associated with moyamoya disease

We describe a patient with moyamoya disease associated with an unruptured basilar tip aneurysm which was treated by endovascular embolization using Guglielmi detachable coils (GDCs). A 53-year-old man presented with left hemiparesis persisting for 3 mon ths before admission. Cerebral angiography revealed occlusion of the bilateral middle cerebral arteries and the left anterior cerebral artery, stenosis of the right anterior cerebral artery, and basal moyamoya vessels. In addition, a saccular small aneurysm was seen at the top of the basilar artery. The aneurysm was completely embolized by intraaneurysmal GDCs. Direct surgical clipping is often selected for the treatment of posterior fossa aneurysms in moyamoya disease. However, complete clipping is usually difficult due to the difficulties in operative technique associated with moyamoya disease. We suggest that the endovascular treatment using GDCs is comparatively safe and effective for the treatment of surgically difficult aneurysms in patients with moyamoya disease.

Distal anterior choroidal artery aneurysm in a patient with moyamoya disease: case report

OBJECTIVE AND IMPORTANCE

Distal anterior choroidal artery (AChA) aneurysms in moyamoya disease are rare, with few surgically verified reported cases.

CLINICAL PRESENTATION

We report a rare case of distal AChA aneurysm associated with moyamoya disease in a 48-year-old man who presented with vomiting and severe headache. Computed tomographic scans revealed an intracerebral hematoma in the right temporoparietal lobe and a diffuse intraventricular hemorrhage.

INTERVENTION

The hematoma was removed via computed tomography-guided stereotactic aspiration and ventricular drainage. Cerebral angiography showed a saccular aneurysm located at the distal branch of the right AChA. By means of magnetic resonance imaging, a small signal void lesion was detected in the periventricular area lateral to the trigone of the right lateral ventricle. The aneurysm was accurately accessed via a parietal cortical incision by use of magnetic resonance imaging-guided stereotactic localization. The aneurysm was successfully resected after undergoing trapping of the parent artery, and when the patient was discharged, he had no evidence of neurological deficit. The aneurysm was histologically verified to be a true aneurysm.

CONCLUSION

Direct surgery should be considered in cases of ruptured distal AChA aneurysms located in the periventricular or intraventricular regions.

Long-term natural history of hemorrhagic moyamoya disease in 42 patients

OBJECT

The purpose of this study was to delineate the long-term natural history of hemorrhagic moyamoya disease (MMD).

METHODS

A retrospective review was conducted among 42 patients suffering from hemorrhagic MMD who had been treated conservatively without bypass surgery. The group included four patients who had undergone indirect bypass surgery after an episode of rebleeding. The follow-up period averaged 80.6 months. The clinical features of the first bleeding episode and repeated bleeding episodes were analyzed to determine the risk factors of rebleeding and poor outcome. Intraventricular hemorrhage with or without intracerebral hemorrhage was a dominant finding on computerized tomography scans during the first bleeding episode in 29 cases (69%). During the follow-up period, 14 patients experienced a second episode of bleeding, which occurred 10 years or longer after the original hemorrhage in five cases (35.7%). The annual rebleeding rate was 7.09%/person/year. The second bleeding episode was characterized by a change in which hemisphere bleeding occurred in three cases (21.4%) and by the type of bleeding in seven cases (50%). After rebleeding the rate of good recovery fell from 45.5% to 21.4% and the mortality rate rose from 6.8% to 28.6%. Rebleeding and patient age were statistically significant risk factors of poor outcome. All four patients in whom there was indirect revascularization after the second bleeding episode experienced a repeated bleeding episode within 8 years.

CONCLUSIONS

The occurrence of rebleeding a long time after the first hemorrhagic episode was not uncommon. Furthermore, the change in which hemisphere and the type of bleeding that occurred after the first episode suggested the difficulty encountered in the prevention of repeated hemorrhage.

Intraventricular aneurysms--three case reports

Three rare cases of purely intraventricular aneurysms are described, including a unique aneurysm in the fourth ventricle. A 30-year-old female, a 47-year-old male, and an 11-year-old girl presented with disturbance of consciousness due to massive intraventricular hemorrhage. Digital subtraction angiography revealed an idiopathic peripheral aneurysm in the fourth ventricle in the first patient, and aneurysms in the lateral ventricle associated with moyamoya disease in the latter two patients. The former two aneurysms were treated surgically and histologically confirmed to be pseudoaneurysms. The latter aneurysm disappeared spontaneously within 2 months after onset. The aneurysm in the lateral ventricle was resected via a parietal corticotomy with stereotactic insertion of an 8-Fr silicone tube to guide the approach route. This method was very useful because computerized neuronavigation was not available. The aneurysm in the fourth ventricle was resected via a midline suboccipital approach with C-1 laminectomy. Conservative treatment is usually recommended initially for patients with intraventricular aneurysm because spontaneous cure often occurs. We recommend direct surgery if the size of the aneurysm remains unchanged, because the risk of surgery has decreased recently owing to new techniques for neuronavigation.

A case of posterior cerebral artery aneurysm associated with idiopathic bilateral internal carotid artery occlusion: case report

BACKGROUND

Aneurysms of the posterior circulation are challenging lesions to neurosurgeons, despite improvements in microsurgical techniques and advances in skull base approaches. We present a rare case of a posterior cerebral artery (PCA)-posterior communicating artery (PcomA) junction aneurysm associated with bilateral internal carotid artery (ICA) occlusion successfully treated with an endovascular procedure.

CASE DESCRIPTION

A 57-year-old female presented with sudden onset of severe headache and loss of consciousness. CT scan showed diffuse subarachnoid hemorrhage and acute hydrocephalus. The patient developed severe neurogenic pulmonary edema and shock. Although her neurogenic pulmonary edema did not resolve, she recovered from shock. However, her general condition was so critical and her vital signs so unstable, that direct surgery under general anesthesia was considered too risky. A cerebral angiogram showed complete occlusion of both internal carotid arteries without any Moyamoya vessels. A saccular aneurysm located at the right PCA-PcomA junction was seen. To obliterate the aneurysm and prevent rerupture, the patient underwent coil embolization via an endovascular approach under sedation with local anesthesia. The balloon remodeling technique was useful to prevent occlusion of parent arteries. Finally, four interlocking detachable coils (IDC) with a total length of 44 cm were used to completely obliterate the aneurysm using the balloon remodeling technique. The patient made a full recovery after treatment and the aneurysm remained obliterated 2 years after coil embolization.

CONCLUSIONS

We emphasize the advantages of the endovascular approach for the patient in critical condition. We believe that this is the first report of a PCA-Pcom junction aneurysm associated with bilateral ICA occlusion without moyamoya disease.

The main epidemiological, clinical and morphological features of moyamoya disease in Yugoslavia

Over a period of 22 years, 31 Moyamoya cases have been recorded in Yugoslavia. In this group of the patients comprising four children and 27 adults, peak age incidence is in the third and fourth decades of life. Males and females have been almost equally affected. Familial cases or territorial clustering of the patients have not been noted. In most cases leading symptoms on admission were motor disturbances. In four patients unilateral involvement was observed while in 27 patients bilateral changes of the internal carotid artery were seen.