Neuroport® makes brain biopsy less invasive and easy even in eloquent areas.

Tissue diagnosis of brain tumours in eloquent is often done via needle biopsy but this method yields small samples that may not be representative of the whole tumour. The Neuroport® system enables a larger tumour biopsy to be taken via a burr hole. We report our experience on 5 cases October 2017 and June 2018. Brainlab® navigation was used. The diagnosis in all patients was made without worsening of their modified Rankin scale scores.

Differentiating between Mycotic and Dissecting Aneurysms in a Case of Ruptured Distal Superior Cerebral Artery Aneurysm.

Objective: We present a case of subarachnoid hemorrhage (SAH) due to ruptured mycotic aneurysm found in the distal superior cerebellar artery (SCA). Case Presentation: A 64-year-old man was admitted to our hospital with sudden unconsciousness. He had a history of alcoholism but no family history of SAH. Computed tomography (CT) showed apparent SAH; however, CT angiography (CTA) showed no apparent cause of SAH except for two small aneurysms in the same branch of the left distal SCA. We suspected mycotic aneurysm and prescribed antibiotics. It was difficult to diagnose the condition as mycotic aneurysm because there were no vegetations or caries at the time of admission. Because there were two aneurysms in the same branch with partial dilatation and stenosis, we suspected dissecting aneurysm, but continued to administer antibiotics for possible mycotic aneurysm. After the first operation, we diagnosed mycotic aneurysm because a vegetation and valve degeneration was found. Conclusion: It is difficult to distinguish mycotic aneurysms from dissecting aneurysms because of similar appearance on imaging, especially if no vegetation is found. Nevertheless, it is important to start treatment for mycotic aneurysm. If there is the possibility of mycotic aneurysm, appropriate antibiotics should be administered, and endovascular treatment could be considered for patients with deteriorating conditions.

Absence of Microbleeds Reduces the Risk for Recurrent Intracerebral Hemorrhage.

BACKGROUND: Many known risk factors, including hypertension and hyperlipidemia cause intracerebral hemorrhage (ICH). Recently, microbleeds have been identified as one of the factors leading to ICH. While some patients have been found to have recurrent ICH, risk factors for recurrent ICH are scarcely reported. We conducted an observational study on the risk-factors of recurrent ICH, comparing stroke patients with a single hemorrhagic episode and those with recurrent ICH. METHODS: A retrospective analysis of a single-center database was performed to analyze the clinical presentation and characteristics of patients with a single and recurrent ICH. From January 2016 to December 2017, a total of 317 patients were analyzed based on suspected factors including patients' sex, age, medical history, antiplatelet therapy use, and presence of microbleeds on images. RESULTS: Of the 317 patients, 36 patients (11.4%) developed a second episode of cerebral hemorrhage. Brain magnetic resonance imaging (MRI) of the patients without microbleeds, predicted reduced risk of recurrence. This is the first report strongly associating the presence of microbleeds with the possibility of a recurrent ICH. Other factors under study did not show an apparent association with recurrent ICH probably because of the high statistical significance obtained with the presence of microbleeds. CONCLUSION: Our findings revealed that the absence of microbleeds on images is a factor that strongly predicts a reduced risk for recurrent ICH and that the detection of microbleeds on MRI performed in patients with a single hemorrhagic episode, is useful in defining further therapeutic management. These findings may benefit physicians treating stroke patients.

Trigeminal Neuralgia Caused by a Persistent Primitive Trigeminal Artery Variant and Superior Cerebellar Artery.

Trigeminal neuralgia is caused by compression of the trigeminal nerve by arteries or veins in the posterior fossa. A persistent primitive trigeminal artery variant (PPTAv) is an anomalous artery that may cause trigeminal neuralgia. A 65-year-old man presented with left facial pain. Brain magnetic resonance imaging revealed a PPTAv. Constructive interference in steady state showed that both the PPTAv and the superior cerebellar artery (SCA) compressed the trigeminal nerve. Thus, we performed microvascular decompression and the patient's symptoms improved. PPTAv is a rare anomaly in the posterior fossa that can cause trigeminal neuralgia. Dual compression of the trigeminal nerve by the SCA and PPTAv demonstrates that trigeminal neuralgia may originate from multiple sources. It is therefore important to check preoperative images to adequately treat trigeminal neuralgia.

How to Remove a Penetrating Intracranial Large Nail.

BACKGROUND: The incidence of penetrating intracranial foreign bodies is rare, and to date, not many relevant studies have been published worldwide. In particular, a nail penetrating intracranially, just near the superior sagittal sinus (SSS), is extremely rare. We treated the case of a large nail that penetrated the middle of the head and strategized its removal. CASE DESCRIPTION: A 70-year-old man had experienced headache lasting a day. Computed tomography of the brain revealed a nail penetrating the middle of his head; in particular, the tip of the nail had penetrated the right ventricle, causing a slight subarachnoid hemorrhage. Angiography showed that the nail was very close to the SSS and that the venous flow was normal. However, there was a risk of the nail penetrating through the SSS or injuring other arteries, and we removed the nail directly from the intracranial view to stop bleeding from the SSS or other vessels. Fortunately, there was no bleeding, and we washed the hole created by the nail penetration and concluded the surgery. CONCLUSIONS: Our technique is useful and safe for removing large nails penetrating the head.

[Two Case Reports of Paroxysmal Sympathetic Hyperactivity Following Craniotomy for Cerebral Hemorrhages].

Paroxysmal sympathetic hyperactivity(PSH)is a clinical condition characterized by abnormal paroxysmal surges in sympathetic nervous system activity. PSH is well known to happen after severe head injury and hypoxic encephalopathy. There are reports of cases of PSH developing after stroke, but PSH is not well recognized in the stroke field in Japan. Case 1 is a 79-year-old woman who became unconscious and suffered a large left mixed-type hemorrhage. Emergency craniotomy was performed. Two months postoperatively, she developed a high fever, tachycardia, tachypnea, and decerebrate posture. After taking clonazepam, her symptoms improved, and she was transferred to another hospital. Case 2 is a 67-year-old man with right hemiplegia, a history of thrombectomy for left M1, occlusion and left carotid artery stenting for asymptomatic left severe carotid artery stenosis performed one year previously. Five hours after right corotid artery stenting, he became restless and hemiplegic on his left side. His computed tomography showed extensive cerebral hemorrhage in the right hemisphere necessitating emergency craniotomy. About a month after surgery, he had a high fever, tachypnea, tachycardia, and decerebrate posture. Taking gabapentin improved his symptoms. Prolonged PSH may be a factor greatly impairing activities of daily living in stroke patients. It is important to diagnose and treat PSH early.

Malignant Meningioma Mimicking Chronic Subdural Hematoma.

BACKGROUND: Chronic subdural hematoma (CSDH) is the most common disease encountered in neurosurgery. Diagnoses of CSDH are usually made on the basis of computed tomography (CT) images. In this report, we discuss the case of a patient with meningioma whose findings instead suggested CSDH. CASE DESCRIPTION: A 91-year-old woman complained of dizziness. Brain CT imaging revealed a low-density subdural space, following which we diagnosed her with CSDH. On the same day, we performed burr hole surgery. However, when opening the burr hole and cutting the dura, a light yellowish tumor was observed under the dura. After the operation, her condition deteriorated and she died 2 days later. After 10 days, pathologic examination of the tumor specimen led to a diagnosis of atypical meningioma. CONCLUSIONS: In almost all cases, CSDH can be diagnosed using CT images only. However, our patient's true diagnosis was meningioma, rather than CSDH. We rouse attention not to take it for CSDH with a CT image easily.

Flocculus Herniation and Hearing Disturbance Induced by Remote Tentorial Meningioma: A Case Report.

Tentorial meningiomas, not involving the cerebellopontine angle cistern or cranial nerves, rarely cause symptoms of cranial nerve disturbance. We report a case of a patient with a paramedian tentorial meningioma who presented with hearing loss as a result of indirect compression of the vestibulocochlear nerve by the herniated cerebellar flocculus into the internal acoustic meatus. A 50-year-old woman had presented with hearing loss in her right ear. Magnetic resonance imaging (MRI) revealed a large tentorial meningioma in the right posterior cranial fossa. Constructive interference in steady-state (CISS) imaging demonstrated a non-enhanced solid structure at the ipsilateral cerebellopontine angle cistern and internal acoustic meatus. During surgery, after resection of the tumor, the herniated cerebellar flocculus into the internal auditory canal was observed at the ipsilateral cerebellopontine angle. MRI obtained following meningioma resection demonstrated the herniated flocculus regressing from the fundus of the internal acoustic meatus to the cerebellopontine angle cistern, and her hearing was improved as a result of decompression. This is a rare case report of flocculus herniation caused by remote tentorial meningioma. Patients with paramedian tentorial meningiomas rarely present with hearing loss. In these cases, the causes of the hearing loss (microvascular compression, transformed brainstem, and venous circulation disorders) have been described in the literature. In this report, a new mechanism became evident: a herniated flocculus into the internal acoustic meatus by a tumor can cause hearing loss. MRI, particularly CISS imaging, can clearly show the flocculus during the entire clinical course.

The Microsurgical Relationships between Internal Carotid-Posterior Communicating Artery Aneurysms and the Skull Base.

Objective This study aimed to review the anatomical and clinical characteristics of internal carotid-posterior communicating artery (IC-PC) aneurysms, especially those located close to the skull base. Methods The microsurgical anatomy around the posterior communicating artery (PComA) was examined in a dry skull and five formalin-fixed human cadaveric heads. The clinical characteristics of 37 patients with 39 IC-PC aneurysms, who were treated microsurgically between April 2008 and July 2016, were retrospectively reviewed. Results The anterior clinoid process (ACP), as well as the anterior petroclinoidal dural fold (APF), which forms part of the oculomotor triangle, are closely related to the origin of the PComA. Among the 39 IC-PC aneurysms, anterior clinoidectomy was performed on 4 (10.3%) and a partial resection of the APF was performed on 2 (5.1%). Both of these aneurysms projected inferior to the tentorium, or at least part of the aneurysm's dome was inferior to the tentorium. Conclusion Proximally located IC-PC aneurysms have an especially close relationship with the ACP and APF. We should be familiar with the anatomical relationship between IC-PC aneurysms and the structures of the skull base to avoid hazardous complications.

Different learning curves between stent retrieval and a direct aspiration first-pass technique for acute ischemic stroke.

OBJECTIVEThe clinical outcomes of a direct aspiration first-pass technique (ADAPT) and stent retriever (SR) have been reported to be similar in several observational studies. In this study, procedural and clinical outcomes with ADAPT and SR for the treatment of acute ischemic stroke with large artery occlusion were compared in different time periods.METHODSIn each specific time period, SR and ADAPT were used as the first-line treatment approach for acute ischemic stroke patients with large artery occlusion at the authors' institution. Baseline characteristics, procedural variables, and functional outcome at 90 days were compared between patients treated with SR and those treated with ADAPT. These 2 groups were divided into 3 sequential subgroups to assess the learning curve effects of the endovascular team and individual operators on the procedural variables of each treatment strategy.RESULTSOverall, 89 patients were treated. In the SR group, the recanalization rate was higher (84% vs 65%; p = 0.01) and the procedure time was shorter than in the ADAPT group (median 42 minutes vs 76 minutes, p = 0.04). On the subgroup analysis of the learning curve, the SR group showed more rapid improvement in procedure time than the ADAPT group (p = 0.01 for the team; p < 0.01 for individual operators).CONCLUSIONSIn this initial experience, a higher recanalization rate and shorter procedure time were achieved with SR than with ADAPT. A high recanalization rate with SR was possible with relatively less clinical experience, whereas procedure time dramatically decreased with experience. These observed effects on the learning curve might be useful when choosing the method for initial endovascular treatment of acute ischemic stroke at relatively small stroke centers.

Improving treatment times for patients with in-hospital stroke using a standardized protocol.

BACKGROUND: Previous reports have shown significant delays in treatment of in-hospital stroke (IHS). We developed and implemented our IHS alert protocol in April 2014. We aimed to determine the influence of implementation of our IHS alert protocol. METHODS: Our implementation processes comprise the following four main steps: IHS protocol development, workshops for hospital staff to learn about the protocol, preparation of standardized IHS treatment kits, and obtaining feedback in a monthly hospital staff conference. We retrospectively compared protocol metrics and clinical outcomes of patients with IHS treated with intravenous thrombolysis and/or endovascular therapy between before (January 2008-March 2014) and after implementation (April 2014-December 2016). RESULTS: Fifty-five patients were included (pre, 25; post, 30). After the implementation, significant reductions occurred in the median time from stroke recognition to evaluation by a neurologist (30 vs. 13.5min, p<0.01) and to first neuroimaging (50 vs. 26.5min, p<0.01) and in the median time from first neuroimaging to intravenous thrombolysis (45 vs. 16min, p=0.02). The median time from first neuroimaging to endovascular therapy had a tendency to decrease (75 vs. 53min, p=0.08). There were no differences in the favorable outcomes (modified Rankin scale score of 0-2) at discharge or the incidence of symptomatic intracranial hemorrhage between the two periods. CONCLUSION: Our IHS alert protocol implementation saved time in treating patients with IHS without compromising safety.

Risk of rebleeding in arteriovenous malformations due to impaired venous drainage after radiosurgery.

A 27-year-old woman presented with rebleeding from an intracranial arteriovenous malformation (AVM) 6 years after radiosurgery. Cerebral angiography demonstrated venous drainage change into a single drainer and cortical reflux due to drainage occlusion into the superior sagittal sinus. During surgery, multiple small feeders thought to be occluded on preoperative angiography caused brain swelling, hindering resection of the AVM border plane. Flow changes after radiosurgery, especially impaired venous drainage, may have increased the tendency to rebleeding of the AVM. Scheduled angiography after radiosurgery is recommended, and retreatment for residual AVMs is preferable, especially if venous drainage change occurs.

Basic and translational research on proteinase-activated receptors: the role of thrombin receptor in cerebral vasospasm in subarachnoid hemorrhage.

Cerebral vasospasm is one of the major complications of subarachnoid hemorrhage (SAH). The prevention and treatment of cerebral vasospasm thus plays a critical role in the management of SAH patients. However, the mechanism of cerebral vasospasm still remains elusive, while effective therapeutic strategies also remain to be established. The role of thrombin and its receptor proteinase-activated receptor 1 (PAR(1)) in cerebral vasospasm was investigated using a rabbit double hemorrhage SAH model. The expression of PAR(1) was up-regulated and the contractile response to thrombin was markedly enhanced in the basilar artery of SAH models. The intrathecal administration of a PAR(1) antagonist prevented the up-regulation of PAR(1) and the enhancement of the contractile responses to thrombin in SAH. These observations thus suggest that PAR(1) may play a pivotal role in post-hemorrhagic cerebral vasospasm in SAH. Following SAH, thrombin activates PAR(1), thereby up-regulating the expression of PAR(1), which culminates in the increased contractile response to thrombin in the basilar artery. PAR(1) antagonists are thus anticipated to be a novel therapeutic strategy for cerebral vasospasm. However, further studies are needed before establishing the clinical usefulness of PAR(1) antagonists.

Prevention of the hypercontractile response to thrombin by proteinase-activated receptor-1 antagonist in subarachnoid hemorrhage.

BACKGROUND AND PURPOSE: Cerebral vasospasm is one of the major complications of subarachnoid hemorrhage (SAH). Its pathogenesis still remains elusive, and effective therapeutic strategies are yet to be established. We investigated the role of proteinase-activated receptor-1 (PAR1) in the hypercontractile state in SAH. METHODS: Rabbit double hemorrhage model was used as a model of SAH. The contractile response to thrombin and the PAR1 expression were evaluated in the isolated rings of basilar artery. RESULTS: Thrombin exhibited only a minor contractile effect in the control, whereas it induced augmented contractions in SAH. The expression of PAR1 was upregulated in SAH. Intracisternal injection of PAR1 antagonist E5555 prevented the enhancement of the contractile responses to thrombin in SAH. The maximal prevention was obtained with 2 microg/kg weight/injection. The contractile responses to K(+) depolarization or endothelin-1 remained unaffected. The upregulation of PAR1 was also prevented by E5555 (2 microg/kg weight/injection) to a level similar to that seen in the control. Ex vivo treatment with E5555 (1 micromol/L) inhibited the contraction induced by thrombin, whereas it had little effect on the contraction induced by K(+) depolarization or endothelin-1, in the basilar artery of SAH. E5555 also inhibited the [Ca(2+)](i) elevation induced by thrombin, but not trypsin, in cultured smooth muscle cells. CONCLUSIONS: PAR1 plays a critical role in upregulating PAR1 itself, thereby enhancing the contractile response to thrombin in SAH. PAR1 could thus be a therapeutic target. However, the usefulness of PAR1 antagonist remains to be investigated in vivo.

An infant with an intradural lipoma of the cervical spine extending into the posterior fossa.

BACKGROUND: Intradural lipomas of the cervical spine are very rare. These tumours show no association with spinal dysraphism. We describe an infant with cervical spinal cord lipoma. Surgical decompression of the cord resolved all neurologic deficits. CASE DESCRIPTION: An 8 month old female infant presented with retarded development of motor function in the limbs, in addition to dysphagia. Computed tomography identified a tumour of fat density that extended from the medulla to C7. Magnetic resonance imaging showed hyperintensity on both T1- and T2-weighted images. A fat-suppression sequence demonstrated an area of signal enhancement in the dorsal portion of the tumour following administration of gadolinium. The adjacent spinal cord was normal. Partial removal of the tumour was performed together with decompressive laminoplasty. The enhancing region proved to be fibrous tissue. Motor development resumed in the week following operation. CONCLUSION: Retarded motor development was the main manifestation of this infant's rare spinal tumour. Neuroimaging was of considerable diagnostic value; in particular, fat-suppression magnetic resonance imaging demonstrated details of the tumour and surrounding structures. Decompressive laminoplasty and laminectomy with partial removal of the tumour was effective in reversing clinical deficits.