Impact of Pre-operative Embolization With Onyx for Brain Arteriovenous Malformation Surgery.

Objective: To clarify the safety and efficacy of pre-operative embolization using Onyx liquid embolic agent (Onyx; ev3) compared with N-butyl cyanoacrylate (NBCA; Cordis Neurovascular, Inc.) or coils in cerebral arteriovenous malformation (AVM) surgery. Methods: This was a retrospective review of a prospectively collected clinical database of brain AVMs treated at our institute from January 2005 to March 2021. A total of 38 consecutive patients who underwent AVM resection after pre-operative embolization were included. Based on pre-operative embolization materials, the patients were divided into the pre-Onyx group (n = 16), in which NBCA or coils were used for embolization, and the Onyx group (n = 22). Patient characteristics and treatment results were compared between the two groups. Results: Patient characteristics were comparable between the two groups in terms of age, sex, and rupture status. While the Spetzler-Martin grade was also similar between the two groups, the location of the AVM nidus in the eloquent area was slightly higher in patients in the Onyx group (72.7%) than in patients in the pre-Onyx group (43.8%) (P = 0.09). The embolization rate was higher in the pre-Onyx group (mean: 63.0%; range: 12.7-100%) than in the Onyx group (mean: 50.0%; range: 15.8-100%), but the difference was not statistically significant (P = 0.06). The time needed for surgical removal was shorter in the Onyx group (mean: 354.8 min; range: 144-884 min) than in the pre-Onyx group (mean: 457.9 min; range: 240-1,294 min); however, this difference was not statistically significant (P = 0.13). The amount of intraoperative bleeding was significantly lower in the Onyx group (mean: 129.8 ml; range: 20-540 mL) than in the pre-Onyx group (mean: 448.8 mL; range: 120-1,550 ml) (P = 0.0008). The surgical complication rates were comparable between the two groups (pre-Onyx group, 18.8%; Onyx group, 4.5%; P = 0.29). Conclusions: Pre-operative embolization with Onyx can significantly reduce the amount of intraoperative bleeding in AVM resection and may contribute to safe AVM surgery.

[Rapid Recanalization of Cerebral Venous Sinus Thrombosis Secondary to Severe Dehydration:A Case Report].

A 41-year-old healthy man presented with sudden disturbance of consciousness and convulsion during a marathon. Computed tomography revealed a lateral sinus sign in the posterior fossa, and magnetic resonance(MR)venography revealed a flow gap in the posterior part of the superior sagittal sinus and bilateral transverse sinus, although the other MR image sequences were normal. Laboratory data revealed dehydration, acute kidney failure, and rhabdomyolysis. Owing to immediate correction of dehydration, clinical symptoms and radiological abnormality improved rapidly. Cerebral venous sinus thrombosis(CVST)is a rare condition, accounting for <1% of all stroke cases. In all cases, CVST cannot cause cerebral infarction or hemorrhagic change but in any case, may present a transient ischemic attack-like event because of rapid spontaneous recanalization. Therefore, CVST may occur more frequently than expected.

[A Case of Cerebral Venous Sinus Thrombosis, Secondary to Subclinical Basedow Disease].

Cerebral venous sinus thrombosis(CVST)is a rare condition accounting for <1% of all strokes. It has been linked to a multitude of risk factors, including infections, oral contraceptive use, coronary disease, malignant disease, trauma, surgery, coagulopathy and several others. However, the association between hyperthyroidism and CVST is poorly understood. We describe here a rare case of CVST, secondary to subclinical Basedow disease. A 68-year-old woman with general fatigue, headache, speech disturbance and slow behavior was admitted to our hospital. Computed tomography(CT)and magnetic resonance imaging revealed a fresh infarction in the left temporal lobe, and CT angiography revealed filling defects of superior sagittal sinus and transverse sinus. Moreover, the patient was diagnosed with Basedow disease for the first time, by examination for tachycardia. This case suggests that it is essential to have a new awareness that hyperthyroidism is an important risk factor for CVST.

[A Case of Dural Arteriovenous Fistula in the Anterior Cranial Fossa that Developed Remote from the Craniotomy Site after Surgery].

Dural arteriovenous fistula(dAVF)is relatively rare, and its etiology remains uncertain. Generally, dAVF is thought to be acquired and has been reported to develop secondary to sinus thrombosis, head injury, infection, and surgery. We report a rare case of dAVF in the anterior cranial fossa that developed remote from the craniotomy site after surgery. A 52-year-old man underwent surgery for hypertensive intracerebral hemorrhage 4 years prior. Perioperative imaging modalities demonstrated no abnormal vascular malformation except for an un-ruptured anterior communicating artery aneurysm. Four years later, follow-up magnetic resonance angiography showed abnormal vascular malformation in the anterior cranial fossa, and cerebral angiography demonstrated dAVF. dAVF and aneurysm were successfully treated. Possible formation of a dAVF should be considered after craniotomy.

[A Very Rare Case of Diffuse Subependymal Metastases from Small Cell Lung Carcinoma].

While parenchymal metastases are common in solid systemic cancers, subependymal metastases are rare. Approximately half of the reported cases of intraventricular metastases originate from renal carcinoma. A 65-year-old man presented with general fatigue, appetite loss, nausea, and disorientation. Radiological examination revealed diffuse periventricular tumors. The patient underwent an open biopsy via right frontotemporal craniotomy. The patient was diagnosed with metastatic small cell lung carcinoma after histopathological examination. Although subependymal metastases from solid systemic cancer are very rare, this ventricular wall abnormality in the cancer patients must not be overlooked. Many small subependymal metastases might be missed on routine examination.

Estimation of foot trajectory during human walking by a wearable inertial measurement unit mounted to the foot.

To establish a supportive technology for reducing the risk of falling in older people, it is essential to clarify gait characteristics in elderly individuals that are possibly linked to the risk of falling during actual daily activities. In this study, we developed a system to monitor human gait in an outdoor environment using an inertial measurement unit consisting of a tri-axial accelerometer and tri-axial gyroscope. Step-by-step foot trajectories were estimated from the sensor unit attached to the dorsum of the foot. Specifically, stride length and foot clearance were calculated by integrating the gravity-compensated translational acceleration over time during the swing phase. Zero vertical velocity and displacement corrections were applied to obtain the final trajectory, assuming the slope of the walking surface is negligible. Short, normal, and long stride-length walking of 10 healthy participants was simultaneously measured using the proposed system and a conventional motion capture system to evaluate the accuracy of the estimated foot trajectory. Mean accuracy and precision were approximately 20 ± 50 mm, for stride length, and 2 ± 7 mm for foot clearance, indicating that the swing phase trajectory of the sensor unit attached to the foot was reconstructed more accurately and precisely using the proposed system than with previously published methods owing to the flat floor assumption. Although some methodological limitations certainly apply, this system will serve as a useful tool to monitor human walking during daily activities.

Syringomyelia and arachnoid cysts associated with spinal arachnoiditis following subarachnoid hemorrhage.

A 66-year-old woman with primary Sjogren syndrome developed syringomyelia following two episodes of subarachnoid hemorrhage (SAH) due to the rupture of basilar artery aneurysms. Gait disturbance and abnormal sensation with pain over the foot and abdomen appeared 3 years after the last SAH. Magnetic resonance (MR) imaging revealed a syringomyelia throughout the thoracic cord, from the T2 to T11 levels. In addition, the thoracic cord was compressed by multiple arachnoid cysts in the ventral side of spinal cord. Computed tomography myelography revealed complete block of cerebrospinal fluid (CSF) flow at the T7 level. Surgery for microlysis of the adhesions and restoration of the CSF flow pathway was performed. Postoperatively, leg motor function slowly improved and she could walk unaided. However, abdominal paresthesia was persisted. Postoperative MR imaging revealed diminished size of the syrinxes. We should recognize syringomyelia and arachnoid cysts due to adhesive arachnoiditis as a late complication of SAH. Microlysis of the adhesions focusing on the lesion thought to be the cause of the symptoms is one of the choices to treat massive syringomyelia and arachnoid cysts associated with arachnoiditis following SAH.

[A tentorial dural arteriovenous fistula presenting progressive myelopathy: a case report].

Abstract We report a case of a dural arteriovenous fistula (DAVF) at the tentorium cerebelli, which presented progressive myelopathy. A 68-year-old man with neurological deterioration of the cervical myelopathy visited our hospital. T2 weighted magnetic resonance (MR) imaging showed high signal area and edema from the medulla to the upper thoracic spinal cord with flow voids on the dorsal surface of the cord. Angiography showed right tentorial DAVF, which was supplied by the right meningohypophyseal trunk, the middle meningeal artery, the accessory meningeal artery, and was drained into the posterior spinal veins. The patient underwent right retrosigmoid suboccipital craniotomy, then disruption of the fistula was performed by using micro Doppler sonography following endovascular obliteration of the main feeders. Postoperative angiography showed complete obliteration of the fistula. His daily functioning gradually improved up to 6 months after the surgery. Tentorial DAVFs with clinical manifestation of myelopathy are rare. Considering its aggressive nature, early surgical treatment could be necessary. (Received: November 17, 2010, Accepted: December 18, 2010).

[Preoperative analysis of platelet aggregability in carotid surgery].

To evaluate the relationship between preoperative analysis of platelet aggregability and perioperative complications, we analyzed 42 patients who underwent carotid endarterectomy or carotid artery stenting. The effect of antiplatelet drugs was tested by whole blood aggregometry. ADP (adenosine-diphosphoric acid) and collagen were used as agonists. According to platelet aggregability, patients were classified into 4 groups (class A: highly inhibited, class B: moderately inhibited, class C: normally inhibited, class D: non-inhibited). Seven (32%) of 22 patients were stratified as clopidogrel nonresponders, whereas four (10%) of 40 patients were aspirin nonresponders. Hemorrhagic complications were registered in four patients. All of them were classified as class A. Ischemic complications occurred in two patients, one was classified as class C, the other was class D. Preoperative analysis of platelet aggregability could be useful to reduce the risk of perioperative complications after carotid surgery.

[Dissecting aneurysm of the anterior cerebral artery with Rubinstein-Taybi syndrome--a case report].

UNLABELLED: The Rubinstein-Taybi syndrome (RTS) is defined congenital anomalies and is characterized by postnatal growth deficiency, microcephaly, specific facial characteristics, broad thumbs and big toes, and mental retardation. RTS displays an autosomal dominant inheritance pattern and is typically caused by cAMP response element-binding (CREB)-binding protein deficiency. Various complications such as eye anomalies and a variety of congenital heart defects are reported in such cases. We treated an RTS patient who had a dissecting aneurysm of the anterior cerebral artery. The patient was a 44-year-old man who was brought to our hospital because of sudden left hemiplegia. Magnetic resonance images showed a cerebral infarction caused by anterior cerebral artery dissection. Coil embolization was performed on enlargement of the dissecting aneurysm, and the procedure was successful. CONCLUSION: RTS may be accompanied by cerebrovascular disease.

Malignant transformation of craniopharyngioma associated with moyamoya syndrome.

A 32-year-old man presented with malignant craniopharyngioma associated with moyamoya syndrome manifesting as right visual disturbance. Magnetic resonance (MR) imaging revealed a parasellar mass lesion diagnosed as adamantinomatous craniopharyngioma. He underwent three surgical procedures and repeated courses of radiotherapy, and was able to resume his daily life. MR imaging demonstrated tumor regrowth and bilateral occlusions of the internal carotid arteries (ICAs) with basal moyamoya phenomenon, which might have been induced by irradiation and/or tumor compression, 10 years after the initial manifestations. Sufficient debulking was safely achieved via the transsphenoidal route and histological examination revealed squamous cell carcinoma, indicating malignant transformation of craniopharyngioma. The tumor relapsed after only one month, so transsphenoidal tumor debulking was tried again. However, the postoperative course was unfavorable because of intraoperative bleeding from the right ICA. Malignant transformation of craniopharyngioma may be included in moyamoya syndrome. The treatment strategy should be carefully considered in such a complicated situation.

Significance of the T2*-weighted gradient echo brain imaging in patients with infective endocarditis.

BACKGROUND: Although aneurysm formation accompanying parenchymal hemorrhage is one of devastating complications in the central nerves system (CNS), imaging studies of the brain are not routinely warranted in patients with infective endocarditis (IE). To assess the clinical importance for detecting silent lesions in the central nervous system, we investigated hypointense signal spots detected on the brain T2*-weighted MR imaging in patients with IE. METHODS AND RESULTS: Eleven patients with IE were retrospectively reviewed. Seven patients (63.6%) showed hypointense signal spots on T2*-weighted MR images. The number of hypointense signal spots increased within only a few weeks in five patients. CONCLUSION: The brain T2*-weighted MR imaging in patients with IE may have a potential role to detect CNS lesions with clinical significance of potentially high risk of intracranial hemorrhage. T2*-weighted hypointense signal spots may be specific to brain involvement, and be quite useful in monitoring CNS lesions associated with IE, even if they are asymptomatic.

[Dural arteriovenous fistulas at the craniocervical junction fed by bilateral vertebral arteries with intracranial drainage: a case report].

We report a case of dural arteriovenous fistulas (DAVFs) at the craniocervical junction, which are supplied by the radicular arteries from bilateral vertebral arteries separately, and drainaged into intracranial sinuses. A 58-year-old man with intermittent neck pain visited our hospital. T2-weighted magnetic resonance (MR) imaging showed flow voids on the dorsal surface of the medulla and upper cervical cord without any signal changes suggesting ischemia. Postcontrast MR digital subtraction angiography (MRDSA) showed early venous filling at the craniocervical junction. Angiography demonstrated bilateral fistulas near each vertebral artery penetration point of the dura matter, which were drainaged into the superior and inferior petrosal sinuses. The patient underwent suboccipital craniotomy and laminectomy of the C1, then disruption of the bilateral fistulas was performed by using micro Doppler sonography after intradural exposure of the shunt points. His symptom subsided post operatively, and MRDSA showed no abnormal vessels. Angiography performed 1 week after surgery confirmed complete obliteration of the fistulas. DAVFs at the craniocervical junction fed by bilateral vertebral arteries is extremely rare. Even in such a case, direct interruption of the fistulas using micro Doppler sonography is the most effective treatment. In addition. MRDSA could be useful for screening and perioperative studies.

Positional vertebral artery compression and vertebrobasilar insufficiency due to a herniated cervical disc.

The authors report a case of vertebrobasilar insufficiency caused by vertebral artery (VA) compression due to a herniated cervical disc, which was surgically treated with the aid of intraoperative angiography. This 78-year-old man visited the hospital because of syncope following head rotation. Admission CT scans revealed a calcified mass adjacent to the right lateral process of the C-4 spine. Cervical angiography demonstrated an obstruction of the right VA at this region on rotation of the head to the right. The operation revealed a cervical disc protruding toward the right VA. The disc was surgically removed, and then the decompression of the right VA was confirmed on intraoperative angiography studies. A histopathological examination showed fibrohyaline cartilage, indicating an ossified intervertebral disc. The postoperative course was uneventful, and he has not experienced any syncope since treatment. A cervical disc herniation could be a cause of vertebrobasilar insufficiency by exerting positional compression of the VA. Intraoperative angiography could be quite useful to confirm this condition during decompression surgery for a cervical VA.

The 150th anniversary of Nagasaki University School of Medicine: recovery from the atomic disaster and evolution of the department of neurosurgery.

NAGASAKI IS LOCATED on the western edge of Japan, closer to the Asian continent. Because of this geographical proximity, Nagasaki became a gateway for the introduction of continental culture and civilization to Japan. After the port of Nagasaki was opened for trade with the Portuguese in 1571, Nagasaki had a central role in cultural exchange with the West and China until the latter half of the 19th century. As a result of the political situation, students came to Nagasaki from all over Japan to obtain information on Western science, especially in medicine, turning Nagasaki into a hub for modern academic studies. The first medical facility in Japan educating doctors in the Western style was founded in Nagasaki in 1857. Despite the tragedy of World War II, the medical school arose again. More than 10 000 physicians have completed their studies at the medical school since its founding. The Department of Neurosurgery at Nagasaki University had its origins within the Second Department of Surgery and became an independent department in 1973. The post of professor was assumed by Kazuo Mori and succeeded in 1991 by Shobu Shibata and in 2003 by Izumi Nagata, who holds the post at the time of this writing. Neurosurgery is dynamic and constantly changing at Nagasaki University with work in progress on technological, diagnostic, and surgical innovations that permit the treatment of highly complex cases. In 2007, the 150th anniversary of the founding of Nagasaki University School of Medicine was celebrated with a number of commemorative events.

[Preoperative embolization for cranio-cervical tumors using Gelpart].

BACKGROUND: Preoperative embolization of cranio-cervical tumors is commonly used to reduce intraoperative blood loss. Gelpart is a new collagen embolic agent. Because of its porous structure, it is deformable and tends not to aggregate. The purpose of this study is to evaluate the efficacy of the Gelpart embolization for cranio-cervical tumors. MATERIALS AND METHODS: The shape and size of Gelpart was observed under high-resolution microscope. Eight cases of cranio-cervical tumors were treated with Gelpart embolization. A microcatheter was introduced to the feeding artery and Gelpart, mixed with contrast medium, was injected manually. The effect of the Gelpart embolization was evaluated with MRI and operative specimen. RESULTS: The shape of Gelpart was not spherical, but the surface became smooth after mixture with contrast medium. Gelpart injection proceeded smoothly and it resulted in excellent angiographical devascularization. No complications occurred related to the Gelpart embolization. At surgery, the tumor was soft and was removed easily. Intraoperative blood loss was relatively less than that using often method. Gelpart embolized peritumoral small arteries and induced tumor necrosis. CONCLUSIONS: We reported our preliminary experience of Gelpart for preoperative embolization of cranio-cervical tumors. Gelpart was effective for tumor embolization.

[Vertebral arteriovenous fistula presenting with subarachnoid hemorrhage: a case report].

We report a rare case of a vertebral arteriovenous fistula presenting with subarachnoid hemorrhage (SAH). A 60-year-old man was admitted to our hospital with a sudden onset of headache and neck pain. A neurological examination showed no abnormalities. Computed tomography scans revealed SAH in the pontine cistern and cistern magna. Although the first cerebral angiogram failed to depict the cause of bleeding, the second angiogram on day 15 demonstrated an arteriovenous fistula in the left vertebral artery at C4-5, which was draining into the internal vertebral venous plexus and forming a venous pouch. The fistula was successfully obliterated by transarterial embolization using detachable platinum coils. In patients with SAH with predominance in the posterior fossa, attention should also be paid to spinal vascular lesions. Three-dimensional digital angiography and digital subtraction angiography allow a reliable visualization of such lesions.

[Retrieval of migrated microcatheter with retrieval forceps during cerebral aneurysm embolization: a case report].

Endovascular embolization for a cerebrovascular lesion has been increasingly performed. We experienced disruption of the microcatheter during a cerebral aneurysm embolization and removed the catheter fragment with retrieval forceps. A 56-year-old woman was brought to our hospital because of consciousness disturbance. Radiological examination revealed subarachnoid hemorrhage due to the rupture of an anterior communicating artery aneurysm. Despite endovascular embolization and neck clipping of the aneurysm, the aneurysm recurred. Then, endovascular embolization was performed. During introduction of the microcatheter to the cerebral aneurysm, the microcatheter disrupted spontaneously at the center of the catheter and the distal end of the catheter migrated into the right middle cerebral artery. The proximal part of the catheter fragment was located at the common carotid artery bifurcation. An attempt to retrieve the catheter by snare failed. Then, retrieval forceps were navigated. The catheter fragment was caught at the common carotid artery bifurcation and successfully removed. Subsequently, the cerebral aneurysm was embolized with detachable coils. No additional complication occured. Microscopical observation of the catheter end revealed relatively sharp disruption and extension of the stainless steel blade. Microcatheter disruption and migration is a rare but significant complication of endovascular embolization. Percutaneous technique with retrieval forceps for the extraction of intravascular foreign objects was useful.