Anterior Choroidal Artery Aneurysm Research Articles

Posterior reversible encephalopathy syndrome: a case following reversible cerebral vasoconstriction syndrome masquerading as subarachnoid haemorrhage

Posterior reversible encephalopathy syndrome (PRES) is a neurotoxic clinico-radiological diagnosis typically presenting with headache, encephalopathy and visual disturbance accompanied by a unique neuroradiological pattern of symmetrical parieto-occipital vasogenic oedema. Here we present the case of a 51-year-old woman who presented to hospital following a thunderclap headache, initially thought to be secondary to a subarachnoid haemorrhage (SAH). A tiny anterior choroidal artery aneurysm was demonstrated on cerebral angiogram. At surgical clipping, no evidence of haemorrhage was observed. Post-operatively, the patient developed delayed right-sided hemiparesis, managed with aggressive hypertensive treatment, and later, with onset of septicaemia, central visual loss. Computed tomography (CT) brain scans demonstrated oedematous changes within the parieto-occipital regions bilaterally and later areas of infarction. The initial diagnosis of SAH was revised to reversible cerebral vasoconstriction syndrome (RCVS), which gave rise to PRES. To our knowledge, this is the first reported case of RCVS with concomitant PRES and cerebral infarction.

もやもや病に合併し血行再建術後に消失した末梢性破裂前脈絡叢動脈瘤の1例

もやもや病に合併し血行再建術後に消失した末梢性破裂前脈絡叢動脈瘤の1例

Distal anterior choroidal artery aneurysm following iatrogenic posterior cerebral artery occlusion

Aneurysms of the anterior choroidal artery are uncommon and account for only 2-5% of all intracranial aneurysms. Distal anterior choroidal artery aneurysms are rare and the pathogenesis of this aneurysm may be different from typical proximal ones. We describe an unusual case of ruptured de novo distal anterior choroidal artery aneurysm in a 55 year-old man who had previously undergone endovascular proximal occlusion for a fusiform aneurysm of the ipsilateral posterior cerebral artery (PCA). A comprehensive review of literature using Medline, PubMed and all related journals was also performed. Only 34 reported distal AchoA aneurysms were found: 16 associated with moyamoya disease, 10 idiopathic, two with atherosclerosis, two with arteriovenous malformation, two dissecting, one infectious and one due to trauma. It is probable that the increased hemodynamic stress within the AchoA contributed to the formation and rupture of the reported aneurysm. This late complication needs to be considered when large intracranial vessels are iatrogenically occluded in the management of complex intracranial aneurysms.

Usefulness of motor-evoked potential monitoring during coil embolization of anterior choroidal artery aneurysms: technical reports

Objectives: To determine whether transcranial motor-evoked potential (TCMEP) monitoring is useful for detecting blood flow insufficiency in the anterior choroidal artery (AChA) and reflects motor function during coil embolization of AChA aneurysms.Methods: We analysed MEP findings in seven patients who underwent coil embolization for AChA aneurysms. Corkscrew electrodes positioned at C3 and C4 were used to deliver supra-maximal stimuli (230-550 V). TCMEPs were recorded from the brachioradialis, abductor pollicis brevis, anterior tibialis, and abductor hallucis muscles during all endovascular surgery procedures.Results: Three of seven patients showed transient decreases in TCMEP amplitudes obtained from the lower extremities after coil insertion into the aneurysms, although digital subtraction angiography (DSA) showed no blood flow insufficiency in the AChAs. In two of these three patients, extraction of the coils resulted in recovery of TCMEP amplitudes. In the other patient, the amplitude recovered gradually during repeated TCMEP recordings. One of the three patients experienced transient hemiparesis and aphasia 3 hours after treatment. No patients experienced permanent morbidity post-operatively.Discussion: Decreases in TCMEP amplitude during endovascular treatment for AChA aneurysms are likely to reflect motor dysfunction due to a subtle blood flow insufficiency in the AChA, not detectable by DSA. TCMEP monitoring is a simple and safe monitoring method during coil embolization of AChA aneurysms.

Endovascular Coil Embolization of a Ruptured Distal Anterior Choroidal Artery Aneurysm Associated With Ipsilateral Middle Cerebral Artery Occlusion -Case Report-

An 84-year-old woman with a history of hypertension and a brain infarction presented with a rare distal anterior choroidal artery (AChoA) aneurysm not associated with moyamoya disease manifesting as sudden onset of headache caused by intraventricular hemorrhage. Digital subtraction angiography revealed a peripheral aneurysm in the left AChoA located distal to the plexal point and steno-occlusive changes of the proximal left middle cerebral artery (MCA) and the left posterior cerebral artery (PCA). Collateral arterial channels to the left MCA and left PCA territories were observed along the left AChoA. No neuroimaging findings were compatible with moyamoya disease. Since the aneurysm did not shrink at 2 months after the onset, endovascular treatment was indicated. Under local anesthesia, a microcatheter was placed into the AChoA proximal to the aneurysm with the aid of a 0.008-inch microguidewire. After a provocation test, three detachable platinum coils were delivered into the aneurysm and the parent artery. Complete obliteration of the aneurysm was achieved without additional neurological sequelae. Successful treatment of a ruptured distal AChoA aneurysm associated with atherosclerotic changes of the intracranial arteries was achieved using a meticulous endovascular technique.

内頚動脈‐前脈絡叢動脈分岐部動脈瘤の形態的特徴に基づく分類と手術

In many cases of anterior choroidal artery aneurysms (IC-AChA An), anterior choroidal arteries (AChA) arise from the aneurysmal neck or dome. This is an important reason for a higher rate of surgical complications. We treated 29 cases of IC-AChA An between January 2006 and May 2010, and classified them based on the origin of AChA by retrospective investigation of preoperative 3D-DSA. Cases in which AChA mainly arose from internal carotid arteries were classified as Group 1, those from the aneurysmal neck were classified as Group 2, and those from the aneurysmal dome were classified as Group 3. Thare were 3 cases (10.3%) in Group 1, 21 cases (72.4%) in Group 2 and 5 cases (17.2%) in Group 3. The average of dome /neck ratio was 1.22. Clipping was performed with indocyanine green (ICG) videoangiography in 27 cases and motor evoked potential monitoring (MEP) in 18 cases. There were no ischemic lesions in MRI or neurological dysfunction after surgeries in any of the groups. In 3 of 18 cases with MEP—1 in Group 2 and 2 in Group 3—the amplitudes decreased. In 2 of the 3 cases, ICG videoangiography showed good blood flow. We should keep in mind that ICG videoangiography is not quantitative. ICG videoangiography is very useful, but MEP is routinely needed. Group 1 and Group 2 cases about 90% of all cases, require careful modification of the origin of AChA in clipping. Understanding the origin of AChA using 3D-DSA before surgery is very important to realize good surgical results.

未破裂脳動脈瘤クリッピング術における術中モニタリング―インドシアニングリーンビデオ脳血管造影と電気生理学モニタリングの併用について―

We analyzed the outcome of 62 consecutive patients with unruptured intracranial aneurysm treated by surgical clipping. Thirty-one cases were operated without intraoperative monitoring, 17 cases with indocyanine green videoangiography (ICGA), and 14 cases with electrophysiological monitoring (EPM) in addition to ICGA. Complete obliteration of the aneurysm was confirmed in all 62 cases. Diffusion-weighted imaging of MRI disclosed no ischemic lesions after surgery in any of the cases. Asymptomatic venous infarction was detected by CT study in 2 cases. Cranial nerve palsy occurred in 4 cases but EPM could not detect it. There was no difference among the group without monitoring, the group with ICGA and the group with ICGA and EPM. The mortality and morbidity of all cases was calculated as 0% and 6.5%, respectively. ICGA appeared to be useful in surgery for aneurysms encasing perforators or for repair of problems such as premature rupture. EPA seemed effective in surgery for anterior choroidal artery aneurysms or aneurysms requiring trapping before clipping. However, monitoring would not have been effective without extensive dissection of aneurysms, suggesting that basic microsurgical techniques are crucial for successful surgery.

Unusual Cisternal Coil Migration in the Follow-up Period After Aneurysm Perforation During Endovascular Coiling -Case Report-

A 61-year-old woman suffered cisternal coil migration in the follow-up period after endovascular coil embolization for a ruptured cerebral aneurysm. She presented with sudden onset of headache. Computed tomography demonstrated diffuse subarachnoid hemorrhage, and cerebral angiography disclosed a left anterior choroidal artery aneurysm. The aneurysm was treated by endovascular embolization with Guglielmi detachable coils. During the embolization procedure, the microcatheter perforated the aneurysm. For direct closure of the perforation site with coils, the microcatheter was withdrawn and coils were deployed partially in the subarachnoid space and partially in the aneurysm sac. The coil mass was spread in the subarachnoid space around the aneurysm immediately after embolization. The patient was discharged with no neurological deficit. Three months later, follow-up radiography demonstrated obvious reduction in the size and compaction of the coil mass. Magnetic resonance angiography and digital subtraction angiography demonstrated stable occlusion of the aneurysm. The coil mass probably spread in the cistern around the aneurysm and was compacted by the shape memory of the coils and pulsation of the brain and vessels, as the subarachnoid clots around the aneurysm had disappeared. This case suggests that cisternal coil migration should be considered in the follow up of intracranial aneurysm treated with detachable coils.

Endovascular Embolization of Distal Anterior Choroidal Artery Aneurysms Associated with Moyamoya Disease

We evaluated the feasibility of endovascular embolization for the management of distal anterior choroidal artery (AChA) aneurysms associated with moyamoya disease and performed a literature review to summarize their clinical features and treatment. We describe two cases of moyamoya disease-associated distal AChA aneurysms treated by endovascular embolization. In both cases, a good outcome was observed. We performed a MEDLINE (1980-2010) search which identified 13 similar cases. Our analysis of the clinical data from these 15 cases led us to conclude that (i) endovascular embolization is an effective and feasible treatment for distal AChA aneurysms associated with moyamoya disease; (ii) aneurysm location and the preservation of the parent artery are two major prognostic factors for moyamoya disease-associated distal AChA aneurysms subjected to craniotomy or endovascular therapy; (iii) the parent artery should be preserved when the aneurysm is located in the temporal horn of the lateral ventricle, but sacrificed when it is located in the trigone of the lateral ventricle.

Practical Decision-Making in the Treatment of Unruptured Cerebral Aneurysm in Japan: The U-CARE Study

Background: Decision-making during the management of unruptured cerebral aneurysms is a delicate process for both neurosurgeons and patients. Guidelines are evidence-based references that can aid in making decisions. However, neurosurgeons do not always follow guidelines in clinical practice. The purpose of this study is to verify the hypothesis that there is substantial dissociation between treatment guidelines and practical decision-making due to a bias in treatment selection for unruptured cerebral aneurysms. This bias is dependent upon clinician-driven factors such as experience and specialty, and patient-driven factors such as patient preference. Methods: This study was performed using internet questionnaires. A total of 282 randomly selected, qualified Japanese neurosurgeons (out of approx. 6,000 registered neurosurgeons), including 45 endovascular specialists, participated in this study. Radiological and demographic data from 88 cases of unruptured cerebral aneurysm were opened on the Web. Participating neurosurgeons decided on the treatment for each case (clipping, coiling or observation). Results: Variations in treatment selection were not significant between neurosurgeons and endovascular specialists, except for aneurysms such as anterior choroidal artery aneurysm. However, contrary to the guidelines, aneurysms larger than 10 mm tended to be treated conservatively because the risk of treatment is high, while aneurysms smaller than 5 mm in diameter were often selected for intervention (clipping or coiling). Conclusions: This study revealed that in real-world clinical practice, physicians are not always faithful to the current guidelines. In making practical treatment decisions for unruptured cerebral aneurysms, the patient’s will and the recognition of unavoidable, treatment-related risks seriously influence neurosurgeons’ decisions.

An Aneurysm Rupturing into a Middle Cranial Fossa Arachnoid Cyst Presenting as an Intracystic Hemorrhage

We report a case of an aneurysm rupturing into an arachnoid cyst presenting as a confined intracystic hemorrhage. A 37-year-old man with a history of sporadic headaches for several years complained of a headache of several days' duration. Brain computed tomography and magnetic resonance imaging revealed a cystic lesion in the left side of the middle cranial fossa that included a 3-cm-diameter hematoma in the Sylvian fissure without extracystic hemorrhage. Left carotid artery angiography showed an internal carotid artery-posterior communicating artery (IC-PC) aneurysm and an anterior choroidal artery aneurysm. The cyst wall was excised, and the aneurysms were clipped. The bleeding point was the spot at which the IC-PC aneurysm entered the arachnoid cyst. Right oculomotor nerve palsy developed after surgery, but resolved after 3 months. To the best of our knowledge, this is the only fourth report to date in the literature of a confined aneurysm rupturing into an arachnoid cyst.

Microneurosurgical Management of Anterior Choroidal Artery Aneurysms

Microneurosurgical Management of Anterior Choroidal Artery Aneurysms

Neurological Complications and Surgical Outcome in Patients with Anterior Choroidal Segment Aneurysms

ABSTRACTIntroduction: Choroidal segment aneurysms occur in close relation to terminal internal carotid branches and concomitant anatomical variations in the anterior choroidal artery. The authors evaluate the demographics, presentation, operative techniques, and surgical outcome in 13 patients with this aneurysm. Methods: After identifying the study group from a retrospective review of all supraclinoid ICA aneurysms operated in our institution over an 8-year period, analysis was done with respect to the radiological and operative findings and clinical follow-up. Statistical significance for outcome was analyzed using two-tailed Fisher's exact test (p < 0.05). Results: The incidence of choroidal segment aneurysm was 3.02%. Six (46%) patients had Fisher grade III bleed on imaging. Nine (69%) patients had a good surgical outcome. Three patients had ischemic stroke in the anterior choroidal territory. Patient demographics, Hunt and Hess score at presentation, Fisher score on computed tomogram scan, aneurysm characteristics and clip configuration had no bearing on surgical outcome. Conclusions: In patients with anterior choroidal artery aneurysms managed surgically, meticulous surgical exposure, identification of anatomical variations of parent artery, appropriate clip selection and usage of intra-operative Doppler limit ischemic complications, and allay the development of the morbid clinical syndrome associated with anterior choroidal territory infarction.

Endovascular treatment of tiny anterior choroidal artery aneurysms

Objective To evaluate the efficacy and feasibility of endovascular treatment in the management of tiny anterior choroidal artery aneurysms(AChANs) with the maximum diameter not more than 3 mm.Method 12 cases with 12 tiny AChANs treated with endovascular methods from July 1999 to July 2009 were retrospectively evaluated.11 patients presented with spontaneous subarachnoid hemorrhage.Among the 12 aneurysms,9 were ruptured,10 wide -necked and 10 with ipsilateral anterior choroid arteries (AChAs) involved in the necks.Results 6 aneurysms were managed with simple coil embolization,and balloon remodeling technique was used in 1 case.5 cases underwent intravascular stent implantation.Coil packing was done in 4 of 5 aneurysms,and stent implantation alone was used in the remaining aneurysms Immediate postoperative angiography demonstrated complete occlusion in 2 aneurysms,neck remnant in 4 and incomplete occlusion in 5 among the coil packed ones.The anterior choroidal artery syndrome(AChAS)happened in one of the 2 cases whose ipsilateral AChAs were showed occluded by the immediate angiography.Another patient also encountered transient AChAS despite the patent AChA.Intraoperative hemorrhage was encountered in 1 patient,who recovered well after the procedure.With the exception of 1 patient(Hunt and Hess grade 4) who was loss in follow-up duration,there was no hemorrhagic complication during the follow-up period in the remaining 11 patients.Follow-up angiography in 9 patients showed that 3 aneurysms remained stable,3 were getting better,2 aneurysms treated with stent totally healed,and only one aneurysm recanalization was found.Conclusions Endovascular treatment is a feasible and effective therapeutic alternative for tiny AChANs.The AChA should be kept patent during the procedure to avoid AChAS.Stent is helpful for the patency of AChAs and healing of TAChANs. Key words: Anterior choroidal artery aneurysm; Tiny aneurysm; Interventional therapy; Anterior choroidal artery infarction

Recanalization of Completely Thrombosed Non-Giant Saccular Aneurysm Mimicking asDe NovoAneurysm

Partial thrombosis of giant aneurysms is not uncommon however, complete angiographic occlusion occurs less frequently. In the case of non-giant aneurysms, complete thrombosis and recanalization has been rarely reported. A 31-year-old man presented to the emergency department with sudden bursting headache. Brain computed tomography (CT) revealed diffuse subarachnoid hemorrhage on the left side. Both CT angiography (CTA) and digital subtraction angiography showed suspicion of small left anterior choroidal artery aneurysm. We performed surgical exploration. In the operation field, anterior choroidal artery aneurysm of 2 × 2 mm with broad neck and friable appearance was observed. Because we could not clip without sacrificing the anterior choroidal artery, we performed wrapping only. Follow up CTA after 7 months demonstrated 4 mm right internal carotid artery bifurcation aneurysm. The patient underwent aneurismal neck clipping. During the operation, 9 × 13 mm sized thrombosed aneurysm was detected and completely clipped. We initially thought this aneurysm to be a de novo aneurysm however, it was an aneurysm that had recanalized from a completely thrombosed aneurysm. This case report provides an insight into the potential for complete thrombosis and recanalization of non-giant aneurysms.

Endoscopic treatment of distal choroidal artery aneurysm

Distal choroidal artery aneurysms stemming from the lateral wall of the ventricles are rare and are mostly associated with moyamoya disease. The treatment of these aneurysms is difficult because of their deep location. The authors report the case of a 50-year-old woman followed for moyamoya disease presenting with 2 intraventricular hemorrhages. Cerebral angiography showed an aneurysm located on the left distal choroidal artery. Magnetic resonance imaging also demonstrated that the lesion protruded from the lateral wall of the trigone of the left lateral ventricle. Using MR imaging-guided stereotactic localization, the aneurysm was accurately reached endoscopically and successfully resected from the parent artery. The patient was discharged neurologically intact. To the best of the authors' knowledge, this is the first report of a successfully endoscopically treated distal anterior choroidal artery aneurysm. Endoscopic surgery may be added to the armamentarium of procedures used to treat intraventricular aneurysms.

Endovascular treatment of anterior choroidal artery aneurysms

Endovascular treatment (EVT) of anterior choroidal artery aneurysms (AChAA) may be challenging because of the close relationship with the parent artery. The aim of this study was to report our experience with EVT of AChAA. A retrospective review of our prospectively maintained database identified all AChAA treated by embolization. The clinical charts, procedural data and angiographic results were reviewed. From April 2004-August 2008, 11 patients were identified. Five patients presented with a subarachnoid hemorrhage (SAH) and six patients were asymptomatic. Aneurysms size varied from two to 13 mm (mean size=3.6 mm) and nine had an unfavourable neck/sac ratio (>or=0.7). The anterior choroidal artery was arising from the sac (n=6) or from the neck (n=5). Endovascular treatment consisted of balloon-assisted coiling (n=8), coiling (n=2) and stent-assisted coiling (n=1). No procedural complication occurred and all patients had an excellent outcome except one patient who died because of severe vasospasm 8 days after an uneventful EVT. Immediate angiographic control showed six complete occlusions, one neck remnant and four incomplete occlusions. Follow-up controls (mean=18 months) were obtained in eight patients and showed five stable occlusions and three further thrombosis achieving complete occlusion. EVT of AChAA is associated with very good clinical and long-term anatomical results. Because of their small size, unfavourable neck/sac ratio and close relationship with the parent artery, EVT frequently requires the use of adjunctive techniques such as balloon or stent-assisted coiling.

Spontaneous spinal cerebrospinal fluid leak as a cause of coma after craniotomy for clipping of an unruptured intracranial aneurysm

Spontaneous spinal CSF leaks are best known as a cause of orthostatic headache, but may also be the cause of coma. The authors encountered a unique case of a spontaneous spinal CSF leak causing coma 2 days after craniotomy for clipping of an unruptured aneurysm. This 44-year-old woman with autosomal dominant polycystic kidney disease underwent an uneventful craniotomy for an incidental anterior choroidal artery aneurysm. No intraoperative spinal CSF drainage was used. Two days after surgery the patient became comatose with a left oculomotor nerve palsy. Computed tomography scanning revealed a right extraceberal hematoma and loss of gray-white matter differentiation. The hematoma was evacuated and a diagnosis of hemodialysis disequilibrium syndrome was made. Continuous hemodialysis and hyperosmolar therapy were instituted without any improvement. The CT scans were then reinterpreted as showing sagging of the brain, and the patient was placed in the Trendelenburg position which resulted in prompt improvement in her level of consciousness. A CT myelogram demonstrated an upper thoracic CSF leak that eventually required surgical correction. The patient made a complete neurological recovery. Neurological deterioration after craniotomy may be caused by brain sagging caused by a spontaneous spinal CSF leak, similar to intracranial hypotension due to intraoperative lumbar CSF drainage.

Ruptured distal anterior choroidal artery aneurysm

This report describes a patient with a rare distal anterior choroidal artery (AChoA) aneurysm that developed a right intracerebral haematoma and intraventricular haemorrhage and was treated by surgical exploration and clipping via a transtemporal/ventricular approach. The patient was discharged neurologically intact. We review the literature related to these rare aneurysms within the temporal horn, and the surgical anatomy of the AChoA.

Intraventricular Hemorrhage Caused by Peripheral Anterior Choroidal Artery Aneurysm Rupture

Intraventricular hemorrhage is a severe ictal event secondary to several pathological conditions (anticoagulation therapies, hypertension, post-surgical, traumatic, neoplastic, vascular malformations), leading to blockage of CSF flow and possible hydrocephalus, often justifying surgical intervention. We describe an uncommon source of intraventricular hemorrhage in a 54-year-old woman caused by a peripheral anterior choroidal artery aneurysm rupture.