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OBJECTIVES For improved thrombolysis therapy based on ultrasound irradiation, researchers and practitioners would strongly benefit from an easy and efficient in vitro assay system of thrombolysis activity involving irradiated ultrasound. For the present study, we designed a new in vitro sonothrombolysis assay system using a sheet-type clot. METHODS We designed a cell for clot assay, and we confirmed that this clot cell did not significantly intervene in the acoustic field. Using human plasma, we made a sheet-type clot in the cell. Clot thicknesses at 100 points along 4 directions were measured photometrically at a rate of approximately 4 points/s. RESULTS The sonothrombolysis effects at 13 levels of ultrasonic intensity were obtained with only one sheet-type clot. With this method, we used a clinically oriented probe at 0.7 and 0.3 W/cm2 to confirm that sonothrombolysis took place. CONCLUSIONS We successfully established a new, easy, and efficient method for conducting in vitro sonothrombolysis assays. This method involves little intervention of either ultrasound reflection or standing waves in the clot cell. We believe that this new assay method is very useful for fundamental analyses of ultrasound's thrombolysis effects.

Case A 40-year-old man presented to the emergency room with visual impairment, dysesthesia of lower legs, and urinary retention. Two days before admission, he was consulted to the neurology department due to bilateral optic neuritis and scheduled the magnetic resonance imaging of spine. However, the urinary retention deteriorated acutely and he came to the emergency room. On arrival, the plain magnetic resonance image of his spine showed diffuse hyperintensity signals of the spinal cord in T2-weighted images. He was diagnosed with neuromyelitis optica and steroid pulse therapy was initiated. Outcome We began treatment immediately in the emergency room, cooperating with the neurology team. After admission, plasmapheresis was added for his fluctuating symptoms. On hospital day 7, he was discharged without complication. Conclusion It is important to understand the various clinical manifestations of neuromyelitis optica. In emergency settings, immediate steroid therapy is necessary for better outcomes.

Background Although most neurovascular diseases can be treated either by microsurgical or endovascular means, a subset of patients may require a combined approach. Patient transfer from the operating room (OR) to the angiosuite has been a fundamental drawback of this type of approach. Objective The purpose of this study is to report our clinical experience performing combined surgical and endovascular procedures for neurovascular diseases in the hybrid OR. Methods 29 patients with neurovascular diseases underwent combined endovascular and surgical procedures in a single session: 16 were scheduled combined treatment and 13 were emergency combined procedures. Of the emergency cases, three were rescue surgeries after endovascular complications. Three patients had ruptured intracranial aneurysms, eight had unruptured intracranial aneurysms, eight had arteriovenous malformations and eight had arteriovenous fistulae; two patients had either a spinal tumor or dural arteriovenous fistulae. Results All combined procedures were performed in a single session without changing the patient9s surgical position. In cases of ruptured arteriovenous malformations or aneurysms with hematoma, an emergency embolization was performed to assist the surgical procedure. Combined superficial temporal artery–middle cerebral artery (STA–MCA) bypass followed by endovascular parent artery trapping were successfully performed for complex large or giant aneurysms. There were two periprocedural ischemic complications. Of the three patients who underwent surgical rescue after endovascular complications, two remained intact and one died despite immediate surgical procedures. Conclusion A combined endovascular and surgical approach conducted in a hybrid OR provides a new strategy for the treatment of complex neurovascular diseases.

Sonothrombolysis is one of the most feasible methods for enhancing clot lysis with a recombinant tissue plasminogen activator (rt-PA) in cases of acute ischemic strokes. For safe and efficient clinical practices of sonothrombolysis, accurate estimation of ultrasound transmittance through the human skull is critical. Previously, we reported substantial and periodic fluctuation of ultrasound transmittance through a bone-phantom plate following changes to ultrasound frequency, the thickness of the bone-phantom plate, and the distance between a transducer and the bone-phantom plate. In the present study, we clarify the transmittance behavior of medium-frequency ultrasound (from 400kHz to 600kHz) through the human skull, and examine reduction of the transmittance fluctuation. For the study, we measured transmittance of sinusoidal ultrasound waves at 400kHz, 500kHz, and 600kHz at 13 temple spots on 3 human skulls by changing the distance between a transducer and the skull bone, and found substantial and periodic fluctuation in the transmittance behaviors for these sinusoidal voltage excitations. Degrees of the fluctuation varied depending on the measurement spots. A fluctuation ratio between the maximum transmittance and the minimum transmittance reached 3 in some spots. This large transmittance fluctuation is considered to be a risk factor for sonothrombolysis therapies. We examined a modulated ultrasound wave to reduce the fluctuation, and succeeded in obtaining considerable reduction. The average fluctuation ratios for 400-kHz, 500-kHz, and 600-kHz waves were 2.38, 2.38, and 2.07, respectively. We successfully reduced the ratio to 1.72 by using a periodic selection of random frequency (PSRF)-type of modulation wave. The thus obtained results indicate that attention to the fluctuation in ultrasound transmittance through the skull is necessary for safe and effective sonothrombolysis therapies, and that modulated ultrasound waves constitute a powerful method for reducing the risk of fluctuation.

Object The purpose of this study was to evaluate initial experiences in a surgical operating room (OR) with a multi-purpose angiography unit, which offers integrated neurosurgical and radiological capabilities. Methods A specially designed biplane digital subtraction (DS) angiography system was installed in the neurosurgery OR. The new suite, which allows three-dimensional DS angiography with C-arm for computerized tomography and microsurgery capabilities, allows the neurosurgeon to perform a wide range of neurosurgical and endovascular procedures. Three hundred thirty-two procedures were performed in the endovascular OR between November 2003 and March 2005. Patients arriving in the emergency department were transferred to the endovascular OR without delay. The neurovascular team performed diagnostic angiography followed by endovascular interventional procedures or surgery. Conclusions The newly designed endovascular OR facilitates safe and systemic treatment of neurovascular disease.

With the availability of new techniques, such as intravascular embolisation and radiosurgery, the therapeutic approach to arteriovenous malformations (AVMs) of the brain has recently been modified. The present study reports the authors, experiences in treating AVMs over the past 13 years. Spetzler-Martin grading of AVMs was I and II in 19 cases, III in 12, IV in 5 and V in 1 case. Four therapeutic regimens were utilised: surgical resection alone, embolisation and resection, and radiosurgery alone or after surgical resection. Generally, for low-grade AVMs (Spetzler-Martin grades I, II and III), the therapeutic choice was surgical resection in 27 cases, in combination with pre-operative embolisation in two of these patients. Two cases received radiotherapy only and one case received radiosurgery after embolisation, while one case was treated conservatively. Of the five cases of grade IV, four required surgical treatment, whereas the fifth case was treated conservatively. Favourable results (good recovery and moderate disability) were obtained in 96% of the low-grade AVMs as compared with the high-grade AVMs (66%) that had a poor outcome (due to primary brain damage resulting from haemorrhage at the onset in three cases and due to postoperative re-bleeding in one case). This report summarises preliminary experience in treating intracranial AVMs by surgical resection, intravascular embolisation and radiotherapy. Good therapeutic results can be expected by combining these therapeutic modalities.

重症頭部外傷血腫除去例における早期予後判定を試みるために,Glasgow coma scale (GCS) 8点以下の32例を予後良好群(11例)と不良群(21例)に分類し,年齢,性別,受傷原因,低血圧および低酸素症の有無,受傷から来院および手術までの時間,GCS,瞳孔異常の有無,CT所見,受傷5日間の頭蓋内圧(ICP),脳灌流圧(CPP),内頸静脈酸素飽和度(SjO2)モニタリング所見を比較検討した。その結果,年齢,GCS,受傷後1日目のICP,受傷当日のCPPで,両群間に有意差がみられた。他の因子では,両群間に明らかな差はみられなかった。しかし,低血圧および低酸素症の存在は予後不良群にやや多い傾向がみられ,また脳虚血を示唆するSjO2 50%未満のエピソードも,不良群に多くみられ,とくに受傷後3日間に集中してみられた。以上の結果より,急性期における予後判定は,一次性脳損傷に加え,受傷当日のCPP値,受傷後1日目のICP値などの二次性脳損傷に関与する諸因子の推移を観察,検討した受傷後3日目に行うことができると考えられた。

A 54-year-old man developed transient cardiac arrest due to malignant hyperthermia (MH) during clipping of a cerebral aneurysm. He was found to have unruptured middle cerebral artery aneurysms on both sides. At the first operation, on the left aneurysm, anesthesia was induced by thiopental and vecronium and maintained by isoflurane, nitrous oxide and oxygen. He suddenly developed cardiac arrest soon after an arrythmia of grade 3 A-V block which occurred 6.5 hours after the operation had started. Fortunately the heart recovered after 20 minutes of cardiopulmonary resuscitation. After this accident, the rectal temperature rose to 41.5°C with the manifestation of macro hematuria, metabolic acidosis, and elevation of the levels of serum enzymes GOT, LDH, and CPK. At this point, we suspected MH. Five weeks after the first operation, the second operation, on the right aneurysm was performed. Before anesthesia, dantrolene sodium was administered and a percutaneous pacemaker was inserted intravenously. Balance anesthesia was induced and the second operation was completed uneventfully. We should keep in mind that dantrolene should always be prepared and injected immediately under general anesthesia whenever MH is suspected.

Age is an important factor influencing outcome after severe traumatic brain injury (TBI). In general, the older the victim, the higher the probability of a poor outcome. To investigate the mechanism underlying the link between age and outcome, the data for 797 patients enrolled in the Japan Neurotrauma Data Bank (JNTDB), aged 6 years or older, with Glasgow Coma Scale (GCS) scores of 8 or less on admission or deterioration to that level within 48 h of impact were analyzed. Thirty-eight percent of the patients were between the ages of 40 and 69 years, and 24% of the patients were older than 69 years. Older patients had higher rates of mortality and lower rates of favorable outcome. The frequency of mass lesions which were associated with poorer outcomes significantly increased with age, but regardless of the intracranial lesion type, older patients had poorer outcomes. The GCS score and the occurrence of systemic complications did not differ significantly according to age. Multiple systemic injury was less frequent in older patients. The varied occurrence of intracranial lesion types according to age is likely caused by the disparity between the young and aged brain in the progression of secondary brain injury. Alteration in the pathophysiological response, which is related to the development of secondary brain injury in the aging brain, probably contributes to more severe and irreversible brain damage in older patients, and is thus associated with poor outcomes.

A 4-year study (Japan Neurotrauma Data Bank) of the medical treatment of 1002 cases of traumatic brain injuries in Japan was conducted from 1998 to 2001 at 10 emergency medical centers. Patients with severe head injury were eligible for entry with a Glasgow Coma Scale score of 8 or less at admission. Patients who underwent craniotomy were also included. Children under 5 years old were excluded. An original data sheet with 392 items from multi-focal viewpoints, such as etiology of injury, pre-hospital care, initial treatment including neuro-intensive care unit, and surgical treatment, was created. The results show that the patient's age and mechanism of injury are the most important factors in the outcome.

Background: We developed the transcranial targeting low frequency ultrasound thrombolysis system (TCTLoFUT) which will be used for an acute ischemic stroke (AIS). TCT-LoFUT can emit the T beam (500 kHz continuous waveform, 0.72 W/cm) for thrombolysis to a target thrombus with the D beam (2 MHz pulsed waveform, 0.72 W/cm) for diagnostic TC-CFI. We report the in vitro thrombolytic efficacy by TCTLoFUT and estimate the blood flow monitoring in human with a newly developed head-fixture for TCT-LoFUT using a same aspect of commercial probe.

Mild hypothermia (32–34 °C of brain temperature) was used for brain protection in patients with progressive ischemic neurological deficits associated with severe cerebral vasospasm and who did not respond to medical treatment or intravascular angioplasty. Results showed that 2 of 3 patients in Hunt & Kosnik grade I to III and 2 patients who underwent delayed operation on day 5 and 9 each and had ischemic neurological deficits made good recovery with this treatment. Favourable outcome was obtained in 4 of 9 patients in grade IV and V. Mild hypothermia is thought to provide brain protection in critical ischemia due to severe cerebral vasospasm and can lengthen therapeutic time to employ angioplasty and intraarterial Papaverin infusion.

Cerebral angiography demonstrated an ACoA aneurysm in a 63-year-old man with subarachnoid haemorrhage (Fig. 1 a). Although the left OA was clearly seen, the right OA could not be identified. The anomalous OA, which was found later during surgery, had not been seen on the common carotid angiograms in any phases in multiple views. A right pterional craniotomy was performed. An artery 1 mm in diameter was found above the right optic nerve. This artery arose from the proximal (A1) segment of the ACA and entered the optic canal, and was identified as an anomalous OA (Fig. 1 b). Since this artery anchored the A1 segment firmly at its origin, retraction of the frontal lobe was restricted. Thus neck clipping was unavoidably performed through the space behind the right ACA with extensive resection of the gyrus rectus. Post-operative angiography confirmed completely satisfactory clipping, but the anomalous OA was not demonstrated.

A case of a traumatic middle cerebral artery occlusion resulting from a boxing injury is presented. A 22-year-old man, an amateur boxer, was admitted because of difficulty in speaking, that had appeared a day after a sparring fight. A computed tomographic scan showed low-density areas in the left globus pallidus and corona radiata. A carotid angiogram indicated complete occlusion of the left middle cerebral artery at its origin and an irregularity and narrowing of the left internal carotid artery in its supraclinoid portion. The patient was discharged 4 weeks after the admission with some persistent expressive dysphasia that diminished during the next month. The clinical features and mechanisms of the traumatic middle cerebral artery occlusion are discussed.

A case is presented in which Escherichia coli seeded a pre-existing chronic subdural hematoma. A 77-year-old woman was admitted to our hospital because of lethargy, left hemiparesis and fever. Drainage through a burr hole was performed with the diagnosis of bilateral chronic subdural hematoma. Operative findings revealed the infected subdural hematoma on the right side and non-infected subdural hematoma on the left side. Cultures of the subdural hematoma grew Escherichia coli. In view of the pyuria, the etiology of the infected subdural hematoma was postulated to be a urinary tract infection. In the majority of 14 reported cases, the causative organisms were Escherichia coli, Salmonella, and the systemic sources of infection included the urinary tract, gastrointestinal disease, or were unknown. The possibility of infected subdural hematoma should be considered when computed tomography findings suggestive of chronic subdural hematoma exist in a patient with signs of infection.

We determined the effect of a centrally administered V1 receptor antagonist of arginine vasopressin on the brain water content in an animal model of vasogenic brain edema. Using adult rats, a cold injury was induced in the left hemisphere of the brain by applying a frozen copper rod. 50 ng of V1 receptor antagonist was administered into the left lateral ventricle 10 minutes prior to and/or 1 hour after injury. Twenty four hours after the cold injury, the brain water and sodium contents and plasma osmolality were measured. The V1 receptor antagonist significantly suppressed the increase of the brain water and sodium contents in the cortical structure adjacent to the lesion without any changes in plasma osmolality. Our results demonstrate the effectiveness of a V1 receptor antagonist of vasopressin on vasogenic brain edema.

A case of multiple intracranial epidermoids is reported. A 38-year-old woman who had a three-year history of hemihypesthesia on the right side of her body, diplopia, gait disturbance, dysarthria, and visual field defect, was admitted. Neurological examination revealed right hemiparesis, bilateral abducens palsies, and cerebellar dysfunction. A computed tomography (CT) scan demonstrated a huge low density area in the left middle cranial fossa and heterogeneous density area in the brain stem. She was diagnosed tentatively as epidermoid in the middle fossa and intraaxial mass of the brain stem. Surgery was performed twice. In the first operation, the temporal mass was removed subtotally. Secondarily, only suboccipital craniectomy was performed. After the second operation, her condition deteriorated due to recurrent aseptic meningitis and aspiration pneumonia. She died three months later. Autopsy revealed that an epidermoid was situated in the brain stem intraaxially and another epidermoid was located in the temporal region independently. An intraaxial epidermoid is a rare entity, especially in the brain stem. There is no report of multiple intracranial epidermoids in the literature. The authors emphasize the necessity to rule out epidermoid, when CT shows a high or heterogeneous density area, even if multiple and/or contrast enhanced.

This study was carried out to clarify the biochemical changes in the cold injured brain and their relationship to pathological changes. The cold lesion was produced by application of a cryoprobe containing liquid nitrogen to the exposed left temporal surface for 1 minute in rats anesthetized with a halothane and oxygen gas mixture. The brain edema developed by this procedure was localized in one hemisphere. The animals were guillotined at scheduled times after the cold injury. The brains were rapidly removed and divided exactly between the two hemispheres. Changes in specific gravity of the brain tissue were measured by the dry-weight method until 4 weeks after the injury. Hematoxylin-eosin and Kliiver-Barrera stains were applied to pathological specimens. Free amino acid and uric acid levels were measured chronologically by using Iriyama's method. Catecholamine levels were analyzed by using high-performance liquid chromatography with electrochemical detection. Water content in the injured hemisphere reached a peak level at 12 hours after the injury, then decreased gradually, and entered the normal range at 1 week after the injury. This results was similar to the previous report. Multiple small hemorrhagic lesions were disclosed 2 hours after the injury. This suggests that a mechanism similar to hemorrhagic infarction might play a role in the development of cold injury. Essential amino acids were increased in the injured hemisphere, while those in the contralateral side remained within normal ranges. This result suggests that, in the injured hemisphere, there was not only nonutilization of the essential amino acids but also disturbance of the blood brain barrier, and that the aerobic glycolytic pathway was maintained normally in the contralateral hemisphere. Norepinephrine and dopamine were lowered, while tyrosine was increased in the early stage of cold injury. This suggests impairment of the catecholamine synthesis followed by nonutilization of catecholamine precursors. Uric acid level was increased immediately after the injury, especially on the injured side, and lowered to near baseline level at 4 weeks after the insult. Although biosynthesis of uric acid in the brain is not fully understood, it seems to be a fine parameter of brain damage.