Introduction: The mini orbitozygomatic approach (mOZA) can relieve frontal lobe retraction and is beneficial for clipping anterior communicating artery (Acom) aneurysms, especially high-position Acom aneurysms. The Acom can easily be observed through the mOZA. In this study, we evaluated the usefulness of the mOZA for Acom aneurysm clipping by comparing various aneurysm orientations.
Materials and Methods: Aneurysm neck position (height and anteroposterior position) and maximum diameter, patient age and sex, and incidence of previous subarachnoid hemorrhage were compared between 5 cases treated via the mOZA and 13 cases treated via the pterional approach (PA) for Acom aneurysm clipping. Furthermore, the appropriateness of the two approaches was assessed by reviewing the intraoperative video.
Results: The mean ages of the mOZA and PA groups were 64.0 and 59.8 years (p = 0.552), respectively. There were 3 male patients (60%) in the mOZA group and 7 (53.8%) in the PA group (p = 1.000). Two patients (40%) in the mOZA group and 8 (61.5%) in the PA group had a previous subarachnoid hemorrhage (p = 0.608). The mean maximum aneurysm diameter was 5.4 mm in the mOZA group and 5.7 mm in the PA group (p = 0.811). The mean height of the aneurysmal neck was significantly higher in the mOZA group (8.3 mm) than in the PA group (5.5 mm; p = 0.045). The mean anteroposterior position was not different between the two groups (8.5 mm vs 5.1 mm, p = 0.216). When the aneurysm neck was located at a height of between 8 and 10 mm from the planum sphenoidale and anteriorly located 10 mm from the jugum sphenoidale, mOZA was considered to be useful for Acom aneurysm clipping on the basis of the review of the intraoperative video.
Conclusion: Understanding the positional relationship between the height and the anteroposterior position of the aneurysm neck is a key factor in considering the mOZA for Acom aneurysms. The approach is especially useful in cases where the aneurysm neck is located at a high level anteriorly.

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We performed clipping surgeries for patients with unruptured middle cerebral artery (MCA) bifurcation aneurysms and used preoperative magnetic resonance (MR) imaging (T2-weighted image; T2WI) and MR angiography (MRA), intraoperative findings, and postoperative computed tomographic scans to investigate 1) whether the subfrontal approach (SFA) with frontal lobe retraction or the transsylvian approach (TSA) can secure a minimum surgical field by less invasive procedures and 2) which site in the Sylvian fissure (SyF) is it the most effective for entering via TSA. TSA is classified into 1) the transproximal Sylvian approach (proximal TSA) by opening the proximal SyF, 2) transmiddle Sylvian approach (middle TSA) by opening the middle SyF, and 3) transdistal Sylvian approach (distal TSA) by opening the distal SyF. Determinants of selecting each approach are not only the length of the horizontal portion of the MCA (M1) and size and location of aneurysms in the deep SyF, but also the width of the anterior operculoinsular compartment (A-OpIC) of the SyF exposed by resection of the sphenoidal ridge and deep sphenoidal compartment (SphC) of the SyF. In conclusion, 1) the SFA is speculated to be appropriate for cases wherein M1 is hidden by aneurysms deeply located inside the narrow SphC; 2) the proximal TSA, for cases wherein M1 and aneurysms are located at the border of the wide SphC and A-OpIC; 3) the middle TSA, for cases wherein M1 and aneurysms are located at the lateral part of the wide A-OpIC; and 4) the distal TSA, for cases wherein long M2 and aneurysms are located in the OpIC.

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Basilar artery trunk aneurysm (BATA) is an aneurysm that occurs between the union of the bilateral vertebral arteries and the superior cerebellar artery. Dissection, in addition to the formation of an aneurysm itself, has been considered a cause of BATA. Direct surgery is difficult in many cases; however, recently, endovascular treatment (EVT) has been used for BATA rupture.
Between November 2007 and October 2015, acute-phase EVT was performed in five cases of ruptured BATA in our hospital. The male-to-female ratio and mean age of the patients were 1:4 and 63.6 years, respectively. The mean (range) maximum diameter of the aneurysm was 9.24 mm (3.2-17.8 mm). Four aneurysms were multilocular and irregular in shape, while two were partially thrombosed. During EVT, the balloon remodeling technique was used in four cases and a stent was used in one case as an adjunctive technique. We encountered two technical problems, namely failure during the delivery of the stent system and in-stent thrombosis. Three cases were exacerbated during the perioperative period and resulted in a modified Rankin score of 6.
In our cases, EVT did not contribute adequately to improving the prognosis of BATA. This study suggests that to perform coil embolization safely and effectively for ruptured BATA, establishing not only the appropriate procedural strategies, including perioperative antiplatelet drugs management, but also a treatment plan that considers disease severity and systemic condition is important.

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We evaluated long-term outcomes in patients treated with carotid endarterectomy (CEA). Postoperative intima-media thickness (IMT) and peak systolic velocity (PSV) were measured using duplex ultrasonography in 38 patients. In addition, the long-term survival of the patients after CEA was assessed. The mean follow-up period was 60 months. The IMT was increased in 15 patients, and changing patterns were categorized into the three following groups: gradual increase, transient peak, and plateau. Postoperative uncontrolled diabetes mellitus (defined as HbA1c level of >7.0) was the only predictor of increased IMT of ≥2 mm. Restenosis (defined as >50% stenosis or >150 cm/s of PSV) or occlusion of the internal carotid artery occurred in 2 patients (5%). In the present case with restenosis, spontaneous restoration was observed after hospitalization without smoking habit for 6 months. Other diseases that required treatment were found in 18 patients (47%) despite routine preoperative systemic examination such as blood examination and chest X-ray photography, and evaluation of current ischemic coronary disease. Of the 18 patients, 6 had cancer and 7 had cardiovascular events. One patient died because of pancreatic cancer, and another patient with acute subdural hematoma had a decrease in modified Rankin scale score. These results indicate that careful postoperative follow-up of IMT and systemic surveillance may play a key role to achieve favorable long-term out-come after CEA.

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Once hyperperfusion occurs after carotid endarterectomy (CEA), artificial hypotension under sedation often needs to be induced until cerebral blood flow (CBF) improves. Arterial spin-labeling magnetic resonance imaging (ASL-MRI) can noninvasively evaluate cerebral blood perfusion. We investigated the usefulness of ASL-MRI in a series of patients with carotid artery stenosis who underwent CEA. We reviewed eight cases of carotid artery stenosis treated with CEA. In the preoperative examination, ASL-CBF had no correlation with the single-photon emission computed tomography (SPECT) -CBF finding (r = 0.03, p = 0.77). However, the ratio of the affected side to the healthy side on ASL-MRI had a significant positive linear correlation with that on SPECT (r = 0.74, p < 0.001). In two patients with hyperperfusion, ASL-MRI detected the hyperperfusion and serially tracked its improvement. Although ASL-CBF was less quantitative than the reference CBF value, it is a useful and noninvasive method to serially evaluate cerebral hemodynamics after CEA.

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The aim of this study was to determine age-related differences in outcome between clipping and coiling in patients with intracranial aneurysms. We retrospectively analyzed 377 consecutive patients (clipping, 304 cases and coiling, 73 cases) dividing them into four groups based on age as follows: <50 years, 50 to 59 years, 60 to 69 years, and ≥70 years. Outcomes were assessed in the perioperative period and 1 year later. Of the cases with perioperative symptomatic events, 7 (2.3%), including 4 cases (1.3%) of symptomatic ischemic stroke, were treated with clipping and none was treated with coiling. All cases of symptomatic perioperative ischemic stroke after clipping occurred in patients aged 60 years (p = 0.027). Events at 1 year occurred only after clipping in 10 cases (3.3%) and after coiling in none of the cases. Eight of 10 patients had chronic subdural hematoma, and all of them were >60 years old (p = 0.028). Favorable outcome was observed for both clipping and coiling in both age groups. Clipping was related to risks of perioperative ischemic stroke and chronic subdural hematoma within 1 year in patients >60 years of age.

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To determine the predictors of medical complications in aneurysmal subarachnoid hemorrhage during the vasospasm stage, we reviewed the medical complications of 92 patients treated for ruptured cerebral aneurysm at our institutions between January 2010 and December 2014.
The 92 patients were divided into medical and non-medical complication groups. Their clinical characteristics were compared, including age, sex, World Federation of Neurological Surgeons (WFNS) grade, vasospasm, medical condition, creatinine (Cr) level, estimated glomerular filtration rate (eGFR), glycemia, cardiothoracic ratio at admission, albumin level, natrium level at onset of medical complication, Cr level 3 days after admission (first period), Cr level at onset of medical complication (second period), eGFR at 3 days after admission (first period), eGFR at onset of medical complication (second period), average intake volume for 3 days (first period), and onset of medical complication (days; second period) after admission by using the Mann-Whitney U test or Fisher test. Univariate and multiple logistic regression analyses were used to determine factors associated with risk of medical complication.
The overall rate of medical complication was 26.1% (24/92). The most common medical complication was pulmonary cardiac complication. The Mann-Whitney U test and univariate analyses showed WFNS grade and eGFR (second period) to be significantly higher in the medical complication group than in the non-medical complication group. The independent risk factors of medical complications that were identified in the multiple analyses were WFNS grade and eGFR (second period; odds ratio, 95% confidence interval: 4.9577, 1.6557-15.0264 and 6.6759, 2.2421-19.8780, respectively).
We identified WFNS grade and eGFR (second period) as independent risk factors. Under the wrong WFNS grade at admission, extensive care should be taken in the management of the disease. When eGFR is less than that at admission during the vasospasm stage, it may play a predictive role for medical complications.

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Relatively small unruptured intracranial aneurysms (UIAs) are often managed conservatively. However, rupture of UIA during follow-up occurs occasionally in clinical situations. We retrospectively analyzed cases of ruptured UIAs followed in our institution between 2012 and 2016. Four patients presented with subarachnoid hemorrhage caused by ruptured aneurysms during observation. We calculated the rupture-risk score on the basis of two meta-analyses previously reported. However, these were not effective to estimate the rupture risk of relatively small aneurysms in these cases. Meanwhile, aneurysmal growth was detected in all the cases, which also had at least one risk factor for aneurysm growth. Thus, increase in aneurysm size might be an indicator of rupture, and a slight growth in size should be carefully and seriously considered as a risk factor of rupture to prevent the rupture of small aneurysms.

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An 89-year-old man presented to our hospital with a pulsatile mass in his neck. Based on magnetic resonance imaging (MRI) and blood tests, he was diagnosed as having an infected aneurysm of the right carotid artery bifurcation. Conservative therapy with antibiotic use was initiated. However, the aneurysm was found to rapidly increase in size. We decided to repair the culprit vessel walls because of the risk of lethal rupture. The aneurysm extended between the common carotid artery (CCA) and internal carotid artery (ICA). Strong adhesions were noted between the walls of the aneurysm and surrounding structures. The wall was difficult to dissect and showed leakage of blood, indicating vascular injury. Thus, resection of the CCA, ICA and external carotid artery (ECA) was performed, followed by reconstruction using a synthetic graft. The patient demonstrated no neurological deficit postoperatively, and postoperative magnetic resonance angiography (MRA) and MRI revealed a patent graft and no new ischemic lesion. Conservative therapy maintained his general condition without any vascular event. Extracranial aneurysms of the carotid artery without any associated history of traumatic events are rare. We discuss the treatment strategy for this condition based on previous reports.

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Thrombosis of cerebral aneurysms increases the risk of rupture and may even lead to cerebral infarction due to the dispersion of thrombus. We describe two case reports for patients who underwent surgical treatment for a symptomatic partially thrombosed aneurysm of the middle cerebral artery (MCA).
Case 1 was a 20-year-old man who presented with a headache. Detailed examination revealed a partially thrombosed large cerebral aneurysm along the right MCA, which was enlarged owing to advanced thrombosis. The patient experienced subarachnoid hemorrhage while awaiting planned surgery and underwent emergency neck clipping of the aneurysm.
Case 2 was a 63-year-old woman who developed cerebral infarction following a right MCA aneurysm growth with thrombosis and underwent emergency coil embolization. She presented with a recurrent aneurysm 3 months later, and underwent a second coil embolization. Both cases showed acute transformation secondary to thrombosis. Urgent treatment is warranted when symptoms related to thrombosis are observed. The treatment strategy should be designed carefully to suit individual cases based on varying anatomy/geometrical patterns of aneurysms and varying progression of thrombosis.

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Superficial temporal artery-middle cerebral artery bypass techniques are widely used to prevent secondary cerebral infarction during internal carotid artery occlusion. However, no effective surgical procedure is available for common carotid artery occlusion. Bonnet bypass using a saphenous vein graft was first described in 1980. However, the saphenous vein graft can easily become twisted and occluded by the tension of the skin flap. Therefore, we create a gutter in the skull to hold and fix the vein graft, using a mini-plate, to prevent such complications. We treated 3 patients with symptomatic (transient ischemic attack or minor stroke) common carotid artery occlusion, with modified Rankin Scale 1-2 and independent activities of daily living. Magnetic resonance imaging did not detect extensive cerebral infarction. Quantitative single photon emission computed tomography showed reduced vascular reserve (stage II) in the left middle cerebral artery territory. Bonnet bypass performed in the chronic phase achieved good patency of the bypass and improved vascular reserve.

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