Background: Traditionally, unruptured internal carotid-posterior communicating artery aneurysms (IC-PC ANs) with oculomotor nerve palsy (ONP) have been considered at a relatively high risk of future rupture. Therefore, surgical treatment is urgently indicated to prevent the presumed impending subarachnoid hemorrhage (SAH). In this article, we reviewed our experiences with IC-PC AN cases diagnosed as impending rupture.

Materials and Methods: We treated 10 patients from December 2012 to April 2017. We reviewed their clinical characteristics and aneurysm images.

Results: The initial symptoms were ptosis or double vision in 3 patients (30%), ipsilateral deep orbital or temporal pain in 5 (50%), and upset eye in 4 (40%). In their first visit to our hospital, 9 patients (90%) had ONP and 7 (70%) had ipsilateral deep orbital pain or temporal pain. All patients underwent successful microsurgical clipping or intravascular embolization and discharged with a modified Rankin scale score of 0 or 1. The mean IC-PC AN diameter was 6.9±2.9 mm. The ANs were irregular in shape and had multiple blebs in all the patients. Furthermore, many ANs had blebs projecting over the top of the ANs; hence, aspect ratios tended to be relatively high (mean, 2.8±1.0). In the surgical clipping cases, we confirmed that the AN blebs seemed extremely fragile and had very thin walls, and intraoperative aneurysm rupture occurred in 3 cases.

Conclusion: In addition to ONP, ipsilateral deep orbital pain or focal headache is an important sign of impending IC-PC AN rupture. Furthermore, the irregular shape, multiple blebs, and projecting bleb over the top of the AN may be characteristic features indicating impending rupture.

Background and Purpose: The superior treatment modality between surgical clipping and endovascular coiling for the treatment of internal carotid-posterior communicating artery aneurysms (IC-Pcom ANs) with oculomotor nerve palsy is controversial. In the present study, we compared clipping and coiling in terms of recovery from oculomotor nerve palsy induced by IC-Pcom ANs.

Materials and Methods: The study included patients treated with clipping or coiling for IC-Pcom ANs with oculomotor nerve palsy over the past 12 years. Age, sex, diabetes mellitus (DM), subarachnoid hemorrhage (SAH), aneurysm size, severity of oculomotor nerve palsy (complete or partial), interval from onset to treatment, degree of recovery from oculomotor nerve palsy, and time to recovery were compared.

Results: Eleven patients were treated with clipping, while four were treated with coiling. No significant differences were found between the clipping and coiling cases in terms of age, sex, DM, SAH, aneurysm size, or proportion of patients with complete oculomotor nerve palsy. The coiling cases tended to be older and have a larger aneurysm. The patients with complete oculomotor nerve palsy tended to be treated with clipping. The interval from onset to treatment was significantly longer in the coiling group than in the clipping group (3.8 days vs. 46 days). The degree of improvement of oculomotor nerve palsy was significantly better in the clipping group than in the coiling group. No significant difference in the proportion of patients with full recovery of the oculomotor nerve was found between the two groups. The time to recovery from oculomotor paresis tended to be longer in the coiling group than in the clipping group.

Conclusion: Although both clipping and coiling achieved good recovery from oculomotor nerve palsy caused by IC-Pcom ANs, clipping may achieve better recovery from complete oculomotor nerve palsy in a short term after onset.

Purpose: The aim of the present study was to assess the recurrence and retreatment rate after coil embolization of unruptured internal carotid artery-posterior communicating artery aneurysms (IC‑PC AN) classified according to the development of the posterior communicating artery (Pcom A) and to determine the risk factor of recurrence.

Methods: The authors examined 42 patients treated with coil embolization for IC‑PC AN in our department. We divided the IC‑PC ANs into 3 groups according to the development of the Pcom A as follows: fetal (group F), adult (group A), and hypoplastic types (group H). Patient data, angiographic findings, treatment information, and follow-up data were analyzed. We also analyzed the recurrence and retreatment rates, and determined the risk factor of recurrence.

Results: The recurrence and retreatment rates had no significant differences among the groups. We found higher-risk aneurysm (large aneurysm of >10 mm, partially thrombosed aneurysm, and recurrent aneurysm post clipping) was the only risk factor of recurrence after coil embolization.

Conclusion: The recurrence rate of Pcom A-preserving coil embolization for IC‑PC AN was not higher than that of coil embolization for IC‑PC AN with hypoplastic Pcom A.

Objective: The prognosis of patients with poor-grade subarachnoid hemorrhage (SAH), especially those with out-of-hospital cardiac arrest (OHCA), is extremely poor. The aim of this study was to assess the prognostic factors and characteristics of patients with SAH with Glasgow Coma Scale (GCS) scores of 3 or 4, including patients with OHCA.

Materials: Forty-two patients with GCS scores of 3 or 4, including 27 with OHCA, were evaluated. They were classified into a favorable outcome group (modified Rankin Scale [mRS] score of 0-2) and an unfavorable outcome group (mRS score of 3-6). The following factors were analyzed: OHCA, rebleeding, brain herniation, location and size of aneurysm, hydrocephalus, and surgical treatment.

Results: Nine patients (21%) underwent a surgical treatment for aneurysms. Five patients (12%) had a favorable outcome at 12 months. Surgical treatment was a significant favorable prognostic factor (p < 0.0001). OHCA (p < 0.005) and brain herniation (p < 0.01) were significant poor prognostic factors. In 24 cases (57%), causative aneurysms could be analyzed, including 18 saccular aneurysms and 6 dissecting aneurysms. Saccular aneurysms were located in the anterior communicating artery in 7 patients (39%) and in the posterior circulation in another 7 patients (39%). All dissecting aneurysms were located at the intradural vertebral artery. Half of the saccular aneurysms were <7 mm in size.

Conclusions: Although patients with OHCA and/or brain herniation inevitably results in poor prognosis, surgical treatment is recommended even for patients with SAH whose GCS score was 3 or 4, when their systemic condition allows.

The low-profile visualized intraluminal support device (LVIS) is a braided stent for stent assist coil embolization for intracranial aneurysms. The LVIS stent has a small stent cell design with higher neck coverage than Enterprise VRD/2 and Neuroform EZ/Atlas. The LVIS stent is applied for parent arteries with diameters ranging from 2.0 to 3.0 mm. In particular, LVIS Jr. enables embolization for distal artery aneurysms with a small parent artery. In this report, the authors reviewed cases of intracranial aneurysm coil embolization using a LVIS stent.

Between September 2015 and September 2016, stent assist embolization with a LVIS stent was performed for 15 patients. LVIS and LVIS Jr. were used in 4 and 11 cases, respectively. In the postprocedural result, complete occlusion was obtained in 12 (80%) of 15 cases and neck remnant was obtained in 3 (20%) of 15 cases.

Clinical complications with neurological deficit were observed in 2 (13%) of 15 cases, including instent occlusion and postoperative subarachnoid hemorrhage. The LVIS stent provided proper coverage of the aneurysmal neck for coiling. Procedural complications without sequelae were observed in 2 (13%) of 15 cases, including stent migration, stuck microcatheter, and flared stent.

LVIS and LVIS Jr. were useful for the stent assist aneurysm embolization; however, appropriate case selection and technical management based on stent characteristics are mandatory.

A3-A3 side-to-side bypass (A3-A3 bypass) is commonly used for revascularization of the anterior cerebral artery territory; however, it is indicated in few patients. This study investigated the indications for A3-A3 bypass based on our clinical experience and a literature review.

The study included 5 patients (3 men and 2 women) who underwent A3-A3 bypass between April 2012 and November 2017. The patients were in their 20s (n = 2), 40s (n = 1), and 50s (n = 2). The diagnoses included unruptured anterior communicating artery aneurysm treated with trapping (n = 1), recurrent enlargement of the anterior communicating artery after clipping (n = 1), anterior cerebral artery dissection (n = 1), anterior cerebral artery stenosis with cerebral infarction (n = 1), and traumatic distal anterior cerebral artery aneurysm (n = 1). A3-A3 bypass was completed and patency was confirmed in all patients.

The requirements for A3-A3 bypass performance include suturing skills for anastomosis, appropriate selection of donor and recipient vessels, and comprehensive preoperative assessment. The indications for A3-A3 bypass are various. When performing a craniotomy for anterior communicating artery aneurysms and distal anterior cerebral artery aneurysms, the A3-A3 bypass can be used as a rescue technique. Therefore, stroke surgeons should master the essential skills. Training in suturing skills is an important part of preparation for the procedure.

Intracranial hemorrhages can occur after carotid revascularization due to cerebral hyperperfusion syndrome (CHS). Subarachnoid hemorrhages associated with CHS after carotid artery stenting (CAS) have been reported in many cases; however, they are rare after carotid endarterectomy (CEA). We report a case of subarachnoid hemorrhage (SAH) associated with CHS after CEA performed in the acute phase of a cerebral infarction.

A 50-year-old man was admitted to our hospital with transient right hemiparesis and dysarthria. Magnetic resonance imaging (MRI) demonstrated a cerebral infarction in the left cerebral hemisphere. Digital subtraction angiography revealed a severe stenosis in the right cervical internal carotid artery. Medical treatment was started; however, cerebral infarction progressed. CEA was performed on the 7th day after admission. On the first postoperative day, MRI demonstrated SAH in the sulcus of the frontal and parietal lobes. Xenon CT revealed an increased cerebral blood flow (CBF) in the left cerebral hemisphere. We diagnosed CHS after CEA. We continued sedation using Propofol and maintained the systolic blood pressure below 120 mmHg using nicardipine. Sedation was stopped on postoperative day 3. The patient was discharged with slight dysarthria on postoperative day 17.

SAH due to CHS is rare but can occur early after CEA. Careful patient management is required after CEA in consideration of SAH due to CHS.

In the treatment of subarachnoid hemorrhage, identifying the ruptured aneurysm is sometimes difficult when the patients have multiple intracerebral aneurysms (MIAs). In a recent study, circumferential enhancement along the aneurysmal wall is reported to be associated with ruptured aneurysm. We report two cases of subarachnoid hemorrhage with MIAs in which magnetic resonance imaging three-dimensional (3-D) T1 fast spin-echo (FSE) was useful for estimating the rupture site.

Case 1: An 87-year-old woman developed subarachnoid hemorrhage (SAH), and magnetic resonance angiography (MRA) detected bilateral internal carotid artery-posterior communicating artery (IC-PC) aneurysms. The right IC-PC aneurysm was large and broad-necked, suggesting difficulties in endovascular treatment. The left aneurysm was smaller; however, it had an irregular-shaped bleb on its wall. Bilateral craniotomies were thought to be exceedingly invasive because of her advanced age. On the 3-D FSE, stronger enhancement was observed along the left IC-PC aneurysm wall than along the right IC-PC aneurysm. The left IC-PC aneurysm was estimated as the ruptured aneurysm, and selective embolization was performed. Her postoperative course was uneventful.

Case 2: An 80-year-old woman developed SAH and was transferred to our hospital 7 days after onset. MRA detected anterior communicating artery (AcomA) and left middle cerebral artery (MCA) aneurysms. The AcomA aneurysm had a bleb on its wall and was likely to be the rupture site. The MCA aneurysm had a broad neck and was unsuitable for endovascular treatment. Craniotomy was thought to be risky because of her advanced age and her admission in the period of cerebral vasospasm. We performed 3-D FSE subsequently to the MRA. Significant enhancement was observed along the bleb of the AcomA; on the other hand, the wall of the MCA aneurysm was not enhanced. We determined the AcomA aneurysm as the rupture site and performed endovascular coil embolization, leaving the MCA aneurysm untreated. Her postoperative course was uneventful and rebleeding was not observed.

Identification of the ruptured aneurysm is the most important problem in the treatment of SAH. However, especially in elderly patients who are intolerant for surgical procedures, radical treatment can lead to a worse outcome. Enhancement of the aneurysmal wall on 3-D FSE can provide a useful finding in the decision of treatment strategies for SAH.

A 75-year-old woman presented with a subarachnoid hemorrhage due to a left internal carotid-posterior communicating artery (IC-PC) aneurysm. Diagnostic angiography revealed that the left posterior communicating artery (Pcom) arose from the aneurysmal dome. At the request of the family, endovascular treatment was performed on the day of onset. As the stent was deployed from the left distal to the proximal internal carotid artery (ICA), the deployment was difficult because of a tortuous vessel. Thus, a stent was deployed into the left Pcom so that the flared proximal end of the stent protruded into the aneurysm neck. Another stent was then placed in the left proximal ICA using the waffle-cone technique; its flared distal end also protruded into the aneurysm neck. The kissing wafflecone stent maintained the antegrade flow in the parent arteries during the coil embolization.

Although intracranial arterial vasospasm commonly occurs after subarachnoid hemorrhage, delayed symptomatic vasospasm rarely occurs after surgical clipping of unruptured intracranial aneurysms. We report the case of a 67-year-old woman who presented with symptomatic vasospasm 10 days after surgical clipping of an unruptured middle cerebral artery aneurysm. On the 10th operative day, the patient presented mild aphasia. Angiography revealed a vasospasm at the left middle cerebral artery. We performed chemical angioplasty and observed an immediate anatomical improvement and clinical recovery. The patient was discharged without deficit.

We report a case of multiple intracerebral hemorrhages that immediately occurred after evacuation of a chronic subdural hematoma along with previous cases described in the literature.

The complications of craniostomy for chronic subdural hematoma mostly have a good prognosis, but serious intracerebral hemorrhage after craniostomy has been reported to be rare but usually devastating.

We performed evacuation and irrigation of a chronic subdural hematoma via a burr hole under local anesthesia for an 87-year-old woman with a previous history of old cerebral infarction. Immediately after the operation, the patient had a general tonic seizure, and computed tomography scan revealed multiple intracerebral hemorrhages. After the operation, moderate left hemiparesis and gait disability remained.

The mechanism and precautionary signs of the onset of intracerebral hemorrhage must be identified. According to previous studies, the incidence rate of intracerebral hemorrhage as a complication of evacuation of chronic subdural hematoma is approximately 0.7-5%. The etiopathogenic mechanism of this complication is presumed to be the rapid surgical decompression of the chronically compressed brain causing a sudden increase in the local cerebral blood flow in the area where changes of the parenchymal vessels had occurred.

This devastating complication can be prevented if closed-system drainage is used for slow decompression while maintaining normotension during and after the surgery.