Objective: Recanalization rates and clinical outcomes of acute internal carotid artery (ICA) occlusion are less favorable than those of middle carotid artery (MCA) occlusion despite using IV recombinant tissue plasminogen activator (rt-PA) therapy or previous-generation thrombectomy devices. We report the treatment outcomes of endovascular reperfusion therapy for acute ICA occlusion after the introduction of stent retrievers (SR).

Methods: After the introduction of SR in our hospital, endovascular intervention for acute ICA occlusion was performed in 26 patients between June 2014 and January 2018. We retrospectively investigated the clinical results and compared them with those of 45 patients with MCA occlusion in same period and those of 11 patients with ICA occlusions before the introduction of SR.

Results: Various etiologies of ICA occlusion were noted in the patients, including atrial fibrillation in 17, myocardial infarction in 2, intracranial atherosclerosis in 2, pre-existing carotid artery stenosis in 3, ICA dissection in 1, and other in 1. Based on the clot morphology and functional collaterals, ICA occlusion were categorized as T or L occlusions in 17 patients and I occlusions in 9. The most effective device for reperfusion was SR in 12 patients, although application of a percutaneous transluminal angiography balloon catheter or an intracranial stent was needed in some cases. Two patients developed symptomatic intracerebral hemorrhage after SR thrombectomy. Successful reperfusion (Thrombolysis in Cerebral Infarction [TICI] 2b or 3) was achieved in 24 patients (92%) in the ICA occlusion group and 37 patients (82%) in the M1 occlusion group. A favorable functional outcome (modified Rankin Scale [mRS] score of 0-2) at discharge was achieved in 13 patients (50%) in the ICA occlusion group and 14 patients (31%) in the M1 occlusion group. No significant differences in recanalization rates (TICI 2b, 3) and good outcomes (mRS scores of 0-2) were found between the ICA and M1 occlusion groups. The rate of successful reperfusion and favorable functional outcomes in patients after the introduction of SR were significantly higher than those reported before the introduction of SR (p = 0.0009 and 0.003, respectively).

Conclusion: The selection of appropriate devices and techniques, including SR thrombectomy, according to stroke etiology has contributed to high rates of successful reperfusion and good functional outcomes in patients with acute ICA occlusion.

Objective: We compared the effect of endovascular treatment for acute ischemic stroke between patients aged >80 years and those aged <80 years.

Patients and Methods: A total of 37 consecutive patients underwent mechanical thrombectomy between July 2014 and November 2016. Patients were divided into 2 groups by age, those aged >80 years (n = 16) and those aged <80 years (n = 21).

Results: There were no significant differences between the two groups regarding preprocedural computed tomography (CT) Alberta Stroke Programme Early CT Score (ASPECTS) (9.1 vs. 8.7), National Institutes of Health Stroke Scale (NIHSS) (20.5 vs. 19.2), and previous intravenous administration of alteplase (56.3% vs. 61.9%). Successful recanalization (Thrombolysis in Cerebral Infarction〔TICI〕 grade 2b, 3) was achieved in 87.5% patients aged >80 years and 81.0% patients aged <80 years. However, the rate of favorable outcomes, such as modified Rankin Scale score of 0-2 at 90 days after stroke, was significantly lower in patients aged >80 years than in those aged <80 years (12.5% vs. 52.4%). In addition, the complication rate, including heart failure, aspiration pneumonia, and urinary infection, was much higher in patients aged >80 years than in those aged <80 years.

Conclusion: Mechanical thrombectomy is safe and effective for acute ischemic stroke, even in patients aged >80 years. However, the clinical outcomes in patients aged >80 years were poorer than those in aged <80 years. A higher incidence of general complications was associated with a poorer prognosis in elderly patients.

Parent artery occlusion is a standard endovascular strategy for subarachnoid hemorrhage due to ruptured vertebral aneurysms. Occasionally, there is no option, except for reconstructing the affective arteries, such as in the case of vertebra-basilar aneurysms with contra-vertebral occlusion.

We treated four cases of ruptured vertebra-basilar aneurysms with stent-assisted coil embolization in the Hokkaido Medical Center between April 2014 and March 2017. Reconstructive treatment was performed for two basilar lesions and two vertebral lesions. Three patients underwent stent-assisted coil embolization in the acute phase, whereas one patient received intentional two-staged therapy, partial embolization in the acute phase, and the stent-assisted coiling approximately a month after the onset.

We present cases of three women and one man, with a mean age of 63.5 years. Follow-up duration was 12-32 months. No re-rupture or ischemic complications were detected, but one case presented with hemorrhagic infarction four days after endovascular balloon angioplasty for vasospasm of the middle cerebral artery. The modified Rankin scale score at 90 days was good (0-1) in two cases (50%). Follow-up magnetic resonance angiography revealed partial recurrence in one case.

The reconstructive technique is a promising treatment for ruptured aneurysms of the posterior circulation in cases when the parent artery should not be sacrificed. Long-term neurologic outcomes vary from patient to patient; therefore, all patients should be carefully followed up.

Intracranial saccular aneurysms are commonly associated with autosomal dominant polycystic kidney disease (ADPKD). However, intracranial dissecting aneurysms have rarely been reported. Here, we report a case of ADPKD associated with an intracranial dissecting aneurysm of the anterior cerebral artery. A 58-year-old female presented with a subarachnoid hemorrhage (SAH), and the angiography showed the pearl and string sign with a small bulge, suggesting rupture of the anterior cerebral artery dissection. She suffered from a second SAH on Day 9, and the angiography demonstrated that the enlargement of the bulge was an aneurysm. Subsequently, she underwent trapping of the right A1 segment together with aneurysm dissection, and the lesion was excised.

Histological examination showed disruption of internal elastic laminas not only in the aneurysmal portion but also in the parent artery (A1), resulting in a final diagnosis of dissecting aneurysm-induced SAH.

Background: Although neuroimaging technology has rapidly advanced over the recent decades, the initial evaluations for an idiopathic subarachnoid hemorrhage (SAH) cannot detect the bleeding source in 15%-20% of cases, and some assessments produce false-negative results. Thus, it is generally recommended that SAH with unknown etiology should be re-evaluated 2 weeks after symptom onset to identify the cryptogenic vascular lesion. Here, we present a case of a dissecting distal superior cerebellar artery (SCA) aneurysm that was detected 4 months after SAH onset.

Case presentation: A 42-year-old female presented with sudden-onset headache and was diagnosed with SAH on computed tomography (CT). Initial evaluation, including angiography, could not identify the bleeding source. Subsequently, several magnetic resonance imaging (MRI) evaluations also failed to detect the bleeding source. An MRI performed 4 months later showed aneurysmal dilatation of the left distal SCA, thought to be the bleeding source. This lesion was successfully treated using endovascular coil embolization.

Conclusion: In cases of SAH with unknown etiology, frequent re-evaluation for a vascular lesion is indicated to avoid delayed re-bleeding. As MRI can non-invasively detect a wide variety of lesions, it may be suitable for repeat evaluation of SAH with unknown etiology.

The rupture-risk scoring systems, PHASES and UCAS, can numerically evaluate the risk of rupture of incidental unruptured cerebral aneurysms (UCA). We investigated 211 patients with UCA, diagnosed and treated for the past 4 years, using these risk-scoring systems and discussed the tendency and validity of our surgical indications retrospectively. When comparing 85 cases judged as surgical indications and 126 cases that became follow-up observations, the aneurysm size, aspect ratio, and the rate of irregularity (bleb) and growth of aneurysm were significantly higher in the surgery group, indicating that operations were performed in selected patients with a higher risk of rupture of UCA. When we compared the locations of the aneurysms in surgical cases, aneurysms arising from bifurcation of the anterior choroidal artery were significantly smaller and showed lower values of PHASES and UCAS scores than those of other locations, reflecting our treatment policy. The PHASES and UCAS scores effectively assist decision-making and surgical indication for UCA; however, the scores may not match the actual clinical judgment of rupture risks for the internal carotid artery aneurysms.

We report the outcomes of patients aged 75 years or older who underwent surgical treatment (coil embolization or clipping) for a subarachnoid hemorrhage at our hospital, from January 2008 to January 2017.

We included 39 patients (age range, 77 to 101 years). Hunt and Kosnik grading upon admission revealed that 18 patients were Grade II, 11 were Grade III, five were Grade IV, and five were Grade V. Twenty-seven patients received coil embolization and 12 received clipping.

Overall, 16 of 39 (41%) patients were in a good clinical state (modified Rankin Scale, 0-3) at discharge. Additionally, 66.7% of patients with Grade II had good outcomes. Favorable outcomes occurred in 50% of patients aged 75-79 years, 52.6% aged 80-89 years, and 0% aged 90 years or older. Complications associated with the surgical procedures were confirmed in seven (17.9%) patients. Furthermore, symptomatic vasospasm was observed in 7.7% of patients. According to the treatment method, favorable outcomes were observed in 33% of patients who received coil embolization and 58.3% of those who received clipping.

Patients younger than 90 years who have a good clinical grade upon admission can be candidates for aneurysm repair treatment.

Hemodialysis in patients with intracerebral hemorrhage may cause dialysis disequilibrium syndrome, in which severe brain edema occurs due to the osmotic gradient resulting in a sudden rise in brain pressure. Based on our recent findings, we report the utility of Goreisan administration for the management of these conditions, i.e., prevention of increased brain pressure and exacerbation of brain edema during hemodialysis.

Goreisan was administered 30 minutes prior to dialysis. The dose was adjusted according to the hematoma size and the degree of brain edema. All 17 patients completed acute phase dialysis and were either transferred to other hospitals or discharged. Three representative cases are reported herein.

The first patient was a 77-year-old woman admitted to the hospital for right thalamic hemorrhage and intraventricular rupture. After stereotactic hematoma aspiration had been performed, increased blood pressure, tachypnea, and anisocoria appeared at the first postoperative dialysis session. We attributed this to a sudden increase in brain pressure, but a crisis was prevented by the administration of an osmotic diuretic. Considering that her condition was disequilibrium syndrome, saireito, a combination of Goreisan and Sho-saiko-to, was administered 30 minutes prior to dialysis. This combination prevented the increase in brain pressure. The second patient was a 45-year-old man hospitalized for right brainstem hemorrhage with intraventricular hematoma. He was treated conservatively. Difficulties at the time of dialysis were prevented by administration of Goreisan prior to dialysis. The third patient was a 74-year-old man who was admitted to the hospital for right thalamus hemorrhage with intraventricular hematoma. His condition was complicated by acute hydrocephalus; therefore, ventricular drainage was performed. Pretreatment with Goreisan prevented a rise in brain pressure during dialysis. Hydrocephalus did not relapse even after drain removal.

Goreisan is a representative treatment for sui disturbance and is considered to be an effective means of managing disequilibrium syndrome, which is an iatrogenic sui disturbance. Its mechanism of action is considered to involve aquaporin 4 in the cell membrane. Goreisan exerts an inhibitory effect on aquaporin 4 and thus may have inhibited the progression of brain edema by inhibiting the sudden transfer of water from the blood vessels to the brain due to the osmotic gradient induced by dialysis. Regarding the acute phase management of patients with intracerebral hemorrhage receiving hemodialysis, administration of Goreisan 30 minutes prior to dialysis is useful for preventing the exacerbation of brain edema.

There are certain cerebral aneurysms, such as large, giant, thrombosed, or fusiform, that are unsuitable for clipping or coil embolization. The flow alteration treatment is considered suitable for these aneurysms. We report a case of a large middle cerebral artery (MCA) aneurysm that was successfully treated by flow alteration in a hybrid operating room (OR). The patient was a 37-year-old woman who was incidentally diagnosed with a right MCA M1 proximal unruptured aneurysm. Digital subtraction angiogram (DSA) on admission revealed an irregularly shaped M1 aneurysm with branching M1 perforators adjacent to an aneurysmal neck. Firstly, we tried to perform direct clipping; however, it was impossible to do so unless M1 perforators were sacrificed. Secondly, we planned the flow alteration treatment for this aneurysm. In a hybrid OR, we performed a right superficial temporal artery (STA)-MCA bypass and an EC-IC high-flow bypass with a saphenous vein graft followed by right neck internal carotid artery (ICA) ligation. According to the findings of the intraoperative DSA, the depiction of an aneurysm was more obvious via the posterior communicating artery (Pcom) by a left vertebral angiogram (VAG) than via the anterior communicating artery (Acom) by a left internal carotid angiogram (ICAG). Therefore, we decided to obliterate the Pcom by a Sugita straight clip. Finally, we confirmed the acceptable reduction in flow into the aneurysm by intraoperative DSA. In a postoperative course, the aneurysm was visualized by magnetic resonance imaging (MRI) and DSA and was seen to have gradually reduced. The patient was discharged without any deficit 25 days after a second operation. A DSA at 8 months after the second operation demonstrated the complete obliteration of the aneurysm. For the flow alteration treatment, it is important to consider the flow dynamics through an aneurysm from multiple blood vessels during the operation. A hybrid OR can facilitate the provision of a safe and clean location to perform intraoperative multi-vessel DSA. Thus, a hybrid OR is very useful for flow alteration treatment of complicated cerebral aneurysms.

We report a case in which spinal nerve disorder caused by cervical hyperextension during carotid endarterectomy was avoided by monitoring transcranial motor evoked potentials.

The patient was a 78-year-old man with severe asymptomatic stenosis of the right internal carotid artery in the neck. We recorded contralateral motor evoked potentials (MEPs) normally during carotid endarterectomy (CEA), but were unable to record ipsilateral MEPs. Preoperative magnetic resonance imaging (MRI) of the cervical cord revealed severe spinal canal stenosis and we concluded that recording MEPs was hindered because the cervical cord had been compressed by the hyperextension of the neck during CEA. When we repositioned the patient’s neck from the hyperextended position to its neutral position, we were able to record ipsilateral MEPs. Owing to the monitoring of transcranial MEPs, we avoided causing postoperative motor paralysis in the patient. The hyperextended position of the neck during CEA increases the risk of postoperative motor paralysis; this can be avoided by using transcranial MEP monitoring.

A 66-year-old man referred to our department had presented with progressive myelopathy for over 2 years. A high-signal-intensity lesion was seen at the cervical spinal cord on T2-weighted magnetic resonance imaging (MRI). Cerebral angiography demonstrated a dural arteriovenous fistula (DAVF) at the craniocervical junction (CCJ), which was fed by the ascending pharyngeal artery and drained into the cervical perimedullary veins. A right suboccipital craniotomy was performed. Dural opening disclosed an abnormally dilated vein posterior to the jugular foramen. The draining vein was surgically coagulated. After surgery, the patient’s symptom subsided. Post-operative cerebral angiography confirmed the complete obliteration of the fistula. On MRI, the abnormal signal of the cervical cord markedly improved. We discuss the surgical strategies for CCJ-DAVF.