We report the results of 14 children with moyamoya disease who underwent simultaneous superficial temporal artery to anterior cerebral artery (STA-ACA) and superficial temporal artery to middle cerebral artery (STA-MCA) bypass combined with extensive indirect revascularization.
In a total of 21 procedures, the median operative time was 6.15 hours, and no patient experienced surgical wound complication. Technical success of STA-ACA bypass was observed in 19 (90.5%) procedures. In the other two cases, the procedure was changed from simultaneous STA-ACA/STA-MCA bypass to STA-MCA double bypass, because the appropriate recipient artery could not be found. In all of the 14 procedures, single-photon emission computed tomography revealed improved cerebral blood flow and vascular reserve in the ACA territory after the operation.
We conclude that simultaneous STA-ACA and STA-MCA bypass combined with extensive indirect revascularization is effective for improvement of hemodynamic insufficiency in the ACA and MCA territories. Moreover, it could prevent surgical wound complication by reducing the need for further surgical procedures in childhood moyamoya disease.

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Extracranial-intracranial (EC-IC) bypass is one of the most fundamental techniques for cerebrovascular surgery. We describe our surgical results and strategy for performing the EC-IC bypass safely and precisely in patients with chronic stage ischemia. Surgical indications were decided for symptomatic internal carotid or middle cerebral artery occlusive disease with misery perfusion detected using quantitative single-photon emission computed tomography. Antiplatelet medications were continued, and intravenous hyperosmotic colloid infusion was started 1 week before operation. Target recipient M4 arteries were superimposed on the superficial temporal artery and cranial bone. Preparation of the superficial temporal artery was performed by using an ultrasound instrument (Harmonic Scalpel^®). The craniotomy site was located under the supratemporal line. Various anastomotic techniques were adopted, including continuous, running, and intermittent suturing methods. The second target recipient artery was confirmed using intra-arterial indocyanine green videoangiography. Hyperbaric oxygen therapy was performed for wound problems. Forty patients (43 sides) underwent EC-IC bypass between September 2010 and March 2015 (mean age, 64.5 years; 28 men and 12 women; double bypass in 35 patients and single bypass in eight). Postoperative complications were chronic subdural hematomas and skin problems in five patients each. None of the patients had permanent deficit. Well-drained operative field and steady hand movements are necessary to perform safe and secure bypass procedures. The various technical tips and surgical strategies that we have suggested can contribute to improving surgical results.

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Hyperbaric oxygen therapy (HBO) was used to treat 9 patients who had delayed wound healing, among 30 patients who underwent a superficial temporal artery-middle cerebral artery bypass from 2014 to 2015. Of these 9 patients, 1 patient was treated after irradiation for intracranial tumor, 1 patient underwent surgical removal of basal cell carcinoma from the contralateral head skin, and 4 patients were undergoing treatment for diabetes mellitus. HBO was performed at an absolute pressure of 2 atmospheres for 75 minutes, with 100% oxygen inhalation. The wounds of all patients successfully healed after 5 to 20 sessions of HBO. Therefore, HBO might be useful for treatment of wounds that fail to heal.

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Considering the excellent results of coil embolization in several clinical studies for cerebral aneurysms, endovascular treatment has often been selected as the first-choice treatment of cerebral aneurysms, even in Japan. However, recurrence, which occurs at a certain probability after coil embolization, is a crucial problem. As a result of the increased use of endovascular treatment, we have experienced increased frequency of recurrent aneurysms after coil embolization.
Many authors have reported that re-coil embolization is safe and efficient for the treatment of recurrent aneurysms after coil embolization. On the other hand, surgical clipping is an alternative option for retreatment, especially in cases unsuitable for coil embolization. Surgical clipping for recurrent aneurysms after coil embolization is performed with or without removal of embolized coils. However, removal of embolized coils entails management of some uncertain elements during the procedure. Therefore, when technically feasible, clipping without removal of embolized coils is preferred.
We present our experience with retreatment of 24 cerebral aneurysms after coiling between 2009 and 2015. Among the 24 aneurysms, 12 were retreated with coiling, and 12 were retreated with clipping. Among the 12 cases with clipping, 10 involved neck clipping and two involved partial clipping of the non-thrombosed portion. In all the cases, clipping was accomplished without coil removal. No neurological complications occurred in any of the cases retreated with surgical clipping.
The management of recurrent lesions of embolized aneurysms requires appropriate choice of treatment that involves using coiling as well as clipping. In these cases, surgical clipping, especially without coil removal, plays an important role in ensuring safe treatment.

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Background: Surgical resection of an arteriovenous malformation (AVM) or fistula (AVF) is often complicated by severe bleeding that is difficult to manage. In order to perform resection successfully, surgical strategy is based on detailed understanding of the anatomy of not only feeders and drainers, but also small perforators; this information is difficult to obtain before surgery. Moreover, in deeper locations, an AVM is often close to important areas such as the pyramidal and optic tracts, and it is important to preserve their functions. In this study, we describe our strategies to overcome these problems, and report our results using illustrative cases.
Methods: From 2006 to 2015, 61 consecutive patients with AVM or AVF underwent surgery at our institution. In order to improve the outcomes of resection and preserve function in all cases, deep perforators were visualized using preoperative three-dimensional (3D) fusion images, and functions were visualized using evoked potentials.
Results: In 6 of 61 cases, evoked potentials decreased during surgery. In 4 cases, decreased motor evoked potentials were associated with transient hemiparesis. One patient developed permanent worsening of hemianopsia. We report 2 illustrative cases of AVM, in which preoperative 3D images were useful in identifying deep small feeders and anatomical relationships between the AVM and surrounding structures, enabling preservation of function.
Conclusions: In the surgical management of a complex AVM or AVF, precise visualization of complex feeders, nidus structures, drainers, and perforating vessels, as well as associated neural functions, using preoperative 3D images and intraoperative evoked potentials, could be useful in functional preservation.

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We summarize our procedure for the diagnosis of the cause of subarachnoid hemorrhage (SAH) and discuss the role of digital subtraction angiography (DSA). From January 2012 to June 2015, 193 patients with nontraumatic SAH were admitted to our institution. All the patients underwent three-dimensional computed tomography angiography (3D-CTA). In 176 (91.2%) of these patients, the cause of SAH was identified by using 3D-CTA. The source of bleeding was detected on DSA on the day of admission in 8 patients (4.1%). However, the origin of the bleeding was unknown in 9 patients (4.7%). Second DSA was performed 4 to 7 days after the onset of SAH in 9 patients with negative angiographic results. Thereby, the cause of SAH was identified in 3 patients. The remaining 6 patients received conservative treatment, as the origin of their SAH was still unknown. Their long-term neurological outcomes were good. Our results showed that most SAH cases could be treated based on 3D-CTA findings alone. However, repeated DSA is necessary for patients with negative results in the initial DSA.

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Objective: We aimed to clarify the risk factors for postoperative chronic subdural hematoma (CSDH) following clipping surgery of unruptured cerebral aneurysms at our institute, where endovascular embolization is the treatment of choice for cerebral aneurysms.
Methods: We reviewed the medical records of 20 patients who underwent clipping surgery for unruptured cerebral aneurysms between January 2010 and April 2014 at our hospital. The relationships between postoperative CSDH and age, sex, location of aneurysm, preoperative Evans index, and the amount of subdural fluid collection at postoperative days 6-14 were analyzed using analysis of variance and logistic analysis.
Results: Nine of 20 patients (45%) developed postoperative CSDH, and 1 patient (5%) required burr hole surgery for symptomatic CSDH. CSDH developed at 7-230 days (average, 55 days) after surgery. The amount of subdural fluid collection at postoperative days 6-14 was significantly higher in patients who developed CSDH than in those who did not (p=0.04). The subdural space cutoff value for CSDH development was 8.2 mm. The ratios of males and middle cerebral artery (MCA) aneurysms were higher in patients with CSDH development than in others, but the differences were not statistically significant. Other factors did not correlate with the occurrence of CSDH.
Conclusion: Postoperative subdural fluid collection was found to be associated with the development of postoperative CSDH after unruptured cerebral aneurysm surgery. Since CSDH may develop more than 6 months after surgery, long-term follow-up of patients is required in cases with large postoperative subdural fluid collection.

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The lateral suboccipital approach is a well-known method for trapping and clipping of a vertebral artery aneurysm (VA-AN). However, in this approach, the deeply situated cranial window and the lower cranial nerves (LCNs) crossing the operative field interfere with the procedure. Here, we describe our alternative mid-lateral suboccipital approach, with the surgical results in 16 recent patients.
Sixteen patients with VA-ANs were admitted to our institute from May 2012 to December 2013. Of these, 2 underwent endovascular treatment. The other 14, including 3 with large VA-ANs, underwent open surgery. These included 8 cases of unruptured and 6 of ruptured VA-ANs. The patients were placed in the prone position. J-shaped skin incisions were made and osteoplastic craniotomies were advanced to the condyle fossa, thus providing wide, superficial operative views.
Trapping was performed in 7 of 14 cases. Proximal clipping was performed in 3 cases and neck clipping in 3 cases.
In our method, the wide, superficial operative field enables the surgeon to apply clips to a high position VA-AN and distal VA from under the LCNs. The method also facilitates occipital artery (OA) avulsion for bypass surgery, if needed.
Thus, the mid-lateral suboccipital approach appears to be an effective alternative to the lateral suboccipital approach.

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The newly developed cotton pad is made of 100% cotton; only the contact surface is coated with polyurethane film. The coated side contains many perforations, so aspiration through the cotton pad is possible from both sides. We used the newly developed cotton pad together with a polyglycolic acid sheet soaked with fibrin glue to control the bleeding from a sutured carotid artery during a carotid endarterectomy (CEA). The newly developed cotton pad could be removed from the hemostat and vessels without difficulty, and no rebleeding was observed after compression by hand for 5 minutes. The polyurethane-coated cotton pad may be useful for controlling the bleeding from a sutured carotid artery during CEA.

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Acute subdural hematoma (SDH) caused by dural arteriovenous fistula (DAVF) of the anterior cranial fossa is usually accompanied by intra-cerebral hemorrhage and/or subarachnoid hemorrhage, and pure SDH is relatively rare. We report a case of a 70-year-old male patient with an acute SDH caused by a ruptured DAVF of the anterior cranial fossa accompanied with a skull fracture, diagnosed by 3D CT angiography (3DCTA). Feeding arteries that branched from the bilateral anterior ethmoidal arteries followed dilated leptomeningeal veins with varix, which drained into the superior sagittal sinus. The patient underwent emergent evacuation of the SDH and resection of the DAVF, including the anterior frontal lobe. A histopathological examination showed a dilated vein with reactively thickening walls surrounded by small vessels in the leptomeninges on the cortex. We emphasize the utility of preoperative 3DCTA in the evacuation of acute SDH.

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A persistent primitive hypoglossal artery (PPHA) is a rare anomalous remnant that can be associated with vascular anomalies such as cerebral aneurysm, moyamoya disease, or arteriovenous malformation. An aneurysm developing in a PPHA associated with unilateral moyamoya disease has not previously been reported. We describe the case of a patient in whom an aneurysm ruptured on a PPHA associated with unilateral moyamoya disease. A 42-year-old man who developed a sudden severe headache followed by unconsciousness was diagnosed with a subarachnoid hemorrhage (SAH) at our hospital. Three-dimensional computed tomography (3D-CT) angiography and catheter cerebral angiography revealed an aneurysm on a left PPHA and left middle cerebral artery occlusion with basal moyamoya vessels. The aneurysm was successfully clipped. The postoperative course was uneventful, and the patient returned to work without neurological deficits three weeks after the surgery.

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