Extremely slow-growing cerebellar ganglioglioma in an elderly patient.

Background: Gangliogliomas account for 0.4% of primary brain tumors. They mainly occur in the supratentorial compartment and typically affect only children and young adults. We present an especially rare case of cerebellar ganglioglioma in an elderly patient. Case Description: A 76-year-old Japanese woman presented with headache and nausea from 1 month previously. She had been diagnosed with a cerebellar tumor in her childhood, but the lesion was asymptomatic at that time, and there was no evidence of an increase in size, so it had been monitored without surgery. At the time of presentation, she had not been examined for approximately ten years. On admission, magnetic resonance imaging indicated a T2 hypertense cyst in the cerebellar vermis. Post-contrast T1 imaging showed an enhanced mural nodule in the cyst. Cerebral angiography showed that none of the vertebral arteries were significant feeders. The tumor was removed through posterior fossa craniotomy. The histopathological diagnosis was ganglioglioma. The patient's headache and nausea improved after surgery. Conclusion: Our patient presented a very rare case of extremely slow-growing elderly ganglioglioma in the cerebellum. In patients with gangliogliomas, long-term follow-up is important because the disease may become symptomatic at an older age.

Factors Associated with Early and Late Seizure Related to Aneurysmal Subarachnoid Hemorrhage.

Post-stroke epilepsy may occur after aneurysmal subarachnoid hemorrhage (aSAH). Both early and late seizures could cause severe neurocognitive deficits if administration of appropriate antiseizure medication is delayed. Therefore, it is important to elucidate the risk factors for early and late seizures, which could be shared with medical teams to promptly manage seizures. There are aspects of both hemorrhage and ischemia in aSAH, and thus, numerous risk factors are considered for early and late seizures. We examined factors associated with aSAH-related early and late seizures. Among 297 patients who had aSAH and underwent direct or endovascular surgery, 25 had early seizures and 20 had late seizures. Patients who did not experience any seizures in at least 2-years of follow-up (n = 81) were used as the control group. Early seizures were associated with older age and acute severe nonneurological infection, whereas late seizures were associated with intraparenchymal lesion volume >10 mL and shunt placement. In patients with late seizures, consistency was frequently observed between electroencephalogram and the presence of intraparenchymal lesions. The frontopolar electrode on electroencephalogram was highly sensitive to abnormality in early seizures. Early seizures were induced by the patient's systemic factors, which may lower the threshold for cortical excitability. Patients with intraparenchymal lesions who undergo shunt placement should be carefully followed up for late seizures.

Hemangioblastoma of the medulla oblongata that caused isolated fourth ventricle after stereotactic radiosurgery: A case report.

Isolated fourth ventricle is a rare complication following shunt insertion of the lateral ventricles for hydrocephalus. The present report describes a rare case of a hemangioblastoma of the medulla oblongata that caused isolated fourth ventricle due to intraventricular deposition of fibrin. A 34-year-old man presented with headache a month before admission. Magnetic resonance imaging indicated multiple tumors in the medulla oblongata and the bilateral cerebellar hemisphere with surrounding edema, and the patient was diagnosed with hemangioblastoma. The patient began to develop progressive headache and nausea after stereotactic radiosurgery, and computed tomography showed obstructive hydrocephalus. Endoscopic third ventriculostomy was performed, and the intraoperative view of this showed that the walls of the lateral and third ventricles were covered with a white membrane-like substance. Endoscopic third ventriculostomy and then ventriculoperitoneal shunt did not improve the hydrocephalus. The patient's consciousness deteriorated due to isolated fourth ventricle and upward herniation. The patient underwent posterior fossa craniotomy and the tumor in the medulla oblongata was removed via a telovelar approach. Intraoperatively, the fourth ventricle was filled with a white membrane-like substance, which was surgically removed and pathologically diagnosed as fibrin. The patient's consciousness and obstructive hydrocephalus improved after surgery. The present case suggests that isolated fourth ventricle may occur after VP shunt placement for the hydrocephalus with hyperproteinorachia.

Hemorrhagic brain metastasis from small-cell carcinoma of the urinary bladder.

BACKGROUND: Small-cell carcinoma of the urinary bladder (SCCB) accounts for 1% of all bladder tumors. We present a rare case of hemorrhagic metastatic brain tumor from SCCB diagnosed by navigation-guided endoscopic biopsy. CASE DESCRIPTION: A 76-year-old man presented with sudden onset of aphasia and right hemiplegia from 3 weeks previously. He had a medical history of prostate cancer and SCCB. Computed tomography showed a mixed density mass in the left basal ganglia. On magnetic resonance imaging, the mass showed mixed intensity in both T1-weighted images and T2-weighted images, suggesting subacute hemorrhage. The mass was partially enhanced with gadolinium. The patient underwent endoscopic hematoma evacuation and partial removal of the tumor. Histopathological diagnosis was neuroendocrine carcinoma, which was consistent with SCCB metastasis. After surgery, the patient underwent whole-brain radiation therapy of 30 Gy. His general condition gradually deteriorated, however, and he died 4 months after surgery. CONCLUSION: Our patient had a rare case of brain metastasis derived from SCCB which presented with cerebral hemorrhage. Navigation-guided endoscopic biopsy was useful for the diagnostic sampling of deep localized brain tumors with hemorrhage.

Regional abnormality of functional connectivity is associated with clinical manifestations in individuals with intractable focal epilepsy.

We explored regional functional connectivity alterations in intractable focal epilepsy brains using resting-state functional MRI. Distributions of the network parameters (corresponding to degree and eigenvector centrality) measured at each brain region for all 25 patients were significantly different from age- and sex-matched control data that were estimated by a healthy control dataset (n = 582, 18-84 years old). The number of abnormal regions whose parameters exceeded the mean + 2 SD of age- and sex-matched data for each patient were associated with various clinical parameters such as the duration of illness and seizure severity. Furthermore, abnormal regions for each patient tended to have functional connections with each other (mean ± SD = 58.6 ± 20.2%), the magnitude of which was negatively related to the quality of life. The abnormal regions distributed within the default mode network with significantly higher probability (p < 0.05) in 7 of 25 patients. We consider that the detection of abnormal regions by functional connectivity analysis using a large number of control datasets is useful for the numerical assessment of each patient's clinical conditions, although further study is necessary to elucidate etiology-specific abnormalities.

Three-dimensional morphology of the superior cerebellar artery running in trigeminal neuralgia.

The superior cerebellar artery (SCA) is the most frequent offending vessel in trigeminal neuralgia. This study aims to elucidate the patterns of the SCA running in 34 patients with typical trigeminal neuralgia using three-dimensional computer graphics. The SCA which runs in the medial aspect of the trigeminal nerve compressed predominantly the root entry zone at the distal segment of the caudal loop. Meanwhile, the SCA which runs in the cranial or lateral aspect of the trigeminal nerve compressed predominantly the mid-third portion at the proximal segment of the caudal loop. The site of neurovascular compression differed depending on the shape of the initial segment of SCA. Transposition methods could not be performed in several patients with arch-shaped SCA. Three-dimensional computer graphics revealed different characteristics of the SCA running in trigeminal neuralgia depending on the site of neurovascular compression and shape of the SCA. These differences might affect procedures for microvascular decompression.

Aphasic status epilepticus of frontal origin treated by resective surgery.

Aphasic status epilepticus (SE) is a clinical entity of SE, but it has not been well recognized. We report a 43-year-old female with a chronic drug-resistant epilepsy with aphasic SE, treated by resective surgery. The patient showed long-lasting weekly episodes of hypokinesia, slow verbal response, and dysphasia, which were diagnosed as symptoms of aphasic SE. Magnetic resonance imaging showed encephalomalacia in the left frontal lobe with a hemosiderin rim. Intracranial electroencephalography revealed continuous spikes, predominantly on the left superior frontal gyrus with hemosiderin deposit. The aphasic symptoms were seen when ictal discharges gradually spread to the wide area of the left anterior frontal lobe, including the language area. The episodes of recurrent aphasic SE had disappeared by one year after the left anterior frontal resection. We should consider aphasic SE when language impairment is episodic, and consider surgical intervention in cases where it repeatedly occurs despite appropriate medical therapy.

[Tentorial Dural Arteriovenous Fistula Presenting with Ocular Symptoms:A Case Report].

Tentorial dural arteriovenous fistula(dAVF)is classified as Cognard 4 with a high risk of aggressive feature, such as intracranial hemorrhage, venous infarction, and intracranial hypertension. We report a rare case presenting with ocular symptoms caused by tentorial dAVF. A 59-year-old man presented with progressive chemosis and exophthalmos of his left eye. Angiography showed a tentorial dAVF that was primarily fed by the middle meningeal artery and the meningohypophyseal artery. The AVF drained into the superior ophthalmic vein and the cerebellar cortical vein via an enlarged petrosal vein. Because transarterial Onyx embolization resulted in incomplete obliteration of the fistula, he underwent microsurgery via a suboccipital approach to obliterate the shunt. Postoperative angiography showed complete obliteration of the shunt. His ocular symptoms rapidly cured. We present this rare case and discuss the pathomechanism associated with the development of ocular symptoms secondary to a tentorial dAVF from the viewpoint of microvascular anatomy.

Rapid regression of glioblastoma following carmustine wafer implantation: A case report.

Carmustine wafers, which are locally delivered chemotherapy in the form of biodegradable implants, confer a survival benefit to patients with glioblastoma (GB) following surgical resection. While the adverse events of this method, including gas retention and perifocal edema, have been extensively investigated, the immediate efficacy of the implant has rarely been reported. To the best of our knowledge, this is the first reported case of GB in which the tumor rapidly regressed after partial surgical removal followed by implantation of carmustine wafers. A 77-year-old woman presented with motor aphasia and right hemiparesis. Neuroimaging revealed a tumor located in the left frontal lobe of the brain. The tumor was partially removed under 5-aminolevulinic acid fluorescence guidance and 8 carmustine wafers were implanted in the resection cavity. The histopathological findings suggested the diagnosis of GB. Genetic and immunohistochemical analyses revealed O6-methylguanine-DNA methyltransferase (MGMT) gene promoter methylation and low MGMT protein expression, respectively, in the tumor cells. One month after the operation, when adjuvant temozolomide chemotherapy was planned, computed tomography and magnetic resonance imaging revealed a marked regression of the residual tumor and perifocal edema. The patient's symptoms and signs had improved. As adjuvant temozolomide without radiation was therapeutically beneficial, the tumor gradually regressed and the patient has remained progression-free for >12 months after the operation. Therefore, adjuvant local chemotherapy with carmustine wafer implants was able to induce rapid regression of GB.

Reduced pallidal output causes dystonia.

Dystonia is a neurological disorder characterized by sustained or repetitive involuntary muscle contractions and abnormal postures. In the present article, we will introduce our recent electrophysiological studies in hyperkinetic transgenic mice generated as a model of DYT1 dystonia and in a human cervical dystonia patient, and discuss the pathophysiology of dystonia on the basis of these electrophysiological findings. Recording of neuronal activity in the awake state of DYT1 dystonia model mice revealed reduced spontaneous activity with bursts and pauses in both internal (GPi) and external (GPe) segments of the globus pallidus. Electrical stimulation of the primary motor cortex evoked responses composed of excitation and subsequent long-lasting inhibition, the latter of which was never observed in normal mice. In addition, somatotopic arrangements were disorganized in the GPi and GPe of dystonia model mice. In a human cervical dystonia patient, electrical stimulation of the primary motor cortex evoked similar long-lasting inhibition in the GPi and GPe. Thus, reduced GPi output may cause increased thalamic and cortical activity, resulting in the involuntary movements observed in dystonia.

Cortically evoked responses of human pallidal neurons recorded during stereotactic neurosurgery.

Responses of neurons in the globus pallidus (GP) to cortical stimulation were recorded for the first time in humans. We performed microelectrode recordings of GP neurons in 10 Parkinson's disease (PD) patients and 1 cervical dystonia (CD) patient during surgeries to implant bilateral deep brain stimulation electrodes in the GP. To identify the motor territories in the external (GPe) and internal (GPi) segments of the GP, unitary responses evoked by stimulation of the primary motor cortex were observed by constructing peristimulus time histograms. Neurons in the motor territories of the GPe and GPi responded to cortical stimulation. Response patterns observed in the PD patients were combinations of an early excitation, an inhibition, and a late excitation. In addition, in the CD patient, a long-lasting inhibition was prominent, suggesting increased activity along the cortico-striato-GPe/GPi pathways. The firing rates of GPe and GPi neurons in the CD patient were lower than those in the PD patients. Many GPe and GPi neurons of the PD and CD patients showed burst or oscillatory burst activity. Effective cathodal contacts tended to be located close to the responding neurons. Such unitary responses induced by cortical stimulation may be of use to target motor territories of the GP for stereotactic functional neurosurgery. Future findings utilizing this method may give us new insights into understanding the pathophysiology of movement disorders.

Ictal asomatognosia due to dominant superior parietal cortical dysplasia.

We report a 23-year-old man with left dominant parietal cortical dysplasia manifesting as ictal asomatognosia. The man had experienced seizures, during which he underwent ictal asomatognosia as a feeling of loss of his right extremities. Scalp electroencephalography (EEG) showed interictal discharges in the left parietal region of his brain. Magnetic resonance fluid-attenuated inversion recovery (FLAIR) imaging revealed a hyperintense lesion in the left superior parietal lobule. A [(123)I]-iomazenil (IMZ) single-photon-emission CT scan demonstrated an area of low IMZ binding coincident with the lesion observed in the MRI scan. Invasive EEG monitoring showed ictal discharges in the cortex posterior to the postcentral sulcus. High-frequency electrical stimulation of the same area of the cortex also induced asomatognosia of the patient's right forearm. We performed a corticectomy of the anterior part of the superior parietal lobule, which resulted in no new neurological deficits. The seizures disappeared after surgery with the maintenance of preoperative medication. Therefore, the anterior part of the superior parietal lobule may be a symptomatogenic zone for ictal asomatognosia.

Nondominant parietotemporal cortical dysplasia manifesting as hypermotor seizures.

We describe the case of a 33-year-old man with nondominant right parietotemporal cortical dysplasia. Habitual seizures were violent, ballistic movements of the extremities with pelvic thrusting, resembling complex gestural automatisms or "hypermotor seizures." Scalp electroencephalography (EEG) and interictal [(123)I]iomazenil single-photon-emission computed tomography revealed an epileptogenic zone including a lesion observed on magnetic resonance imaging. Corticectomy of the inferior parietal lobule was performed via invasive EEG monitoring, but resulted in failed seizure control. The middle and posterior temporal cortices were additionally resected in the second surgery. The patient experienced contralateral hemianopsia postoperatively, but no hemispatial neglect. Hypermotor seizures have not been seen for 1.5years since surgery. This is the first description of a patient with a parietal lobe lesion experiencing hypermotor seizures. The middle and posterior temporal cortices were considered epileptogenic together with the inferior parietal lobule in the present case.

Closed-lip schizencephaly around the central sulcus with intractable epilepsy treated by peri-lesional focus resection.

A 24-year-old man presented with closed-lip schizencephaly around the right central sulcus manifesting as an 11-year history of intractable epilepsy. Mild motor paresis in the left extremities and mental retardation were observed. Tonic posture with bilateral facial tonic contraction was asymmetrical, predominantly in the left extremities. Magnetic resonance imaging demonstrated closed-lip schizencephaly around the right central sulcus. The epileptogenic zone was determined in the supplementary motor area, and premotor and primary sensorimotor cortices using invasive recordings. As the thickened cortex was considered functional, corticectomy of the supplementary motor area and premotor area was performed, preserving the primary sensorimotor area. Histological examination revealed marked cortico-subcortical gliosis, particularly in the medial part of the resection. Asymmetrical tonic postural seizure disappeared completely after surgery. Medically intractable epilepsy with schizencephaly represents a considerable challenge in epilepsy surgery. Partial corticectomy adjacent to the thickened cortex was effective for seizure control in a patient with closed-lip schizencephaly around the central sulcus.

Neurocytoma manifesting as intraventricular hemorrhage--case report.

A 43-year-old man presented with a neurocytoma manifesting as severe headache and disturbance of consciousness. Computed tomography revealed intraventricular hemorrhage, and a small mass lesion with calcification on the wall of the left lateral ventricle. The lesion appeared as mixed intensity regions on both T(1)- and T(2)-weighted magnetic resonance imaging, and heterogeneous enhancement with gadolinium-diethylenetriaminepenta-acetic acid. Angiography showed the pooling sign near the calcification in the late venous phase. Neurologically, amnestic syndrome was demonstrated in the subacute phase. Gross total removal of the lesion was performed through a transcallosal approach. His transient memory disturbance resolved. The histological diagnosis was neurocytoma. Intraventricular hemorrhage is rare as the initial presentation of neurocytoma. Surgery should avoid fornix injury and the risk of permanent memory disturbance.

Pineal Germinoma with granulomatous reaction: case report.

A 20-year-old man presented with diplopia. Neurological examination revealed mild skew deviation and upbeat nystagmus. Computed tomography showed a clover-shaped isodense mass in the pineal region with homogeneous enhancement. The lesion was isointense on both T(1)- and T(2)-weighted magnetic resonance (MR) imaging with homogeneous enhancement by gadolinium-diethylenetriaminepenta-acetic acid. Cerebral angiography showed no tumor staining. Serum and cerebrospinal fluid were negative for beta-human chorionic gonadotropin, alpha-fetoprotein, and placental alkaline phosphatase. Open biopsy was performed using a right occipital transtentorial approach. Histological examination revealed a tumor consisting of clusters of germinoma cells, but with prominent infiltration of lymphocytes, plasma cells, and macrophages, and proliferation of small vessels. The histological diagnosis was germinoma with granulomatous reaction. MR imaging showed complete disappearance of the tumor after chemoradiotherapy. Neurosurgeons should be aware of this rare tumor to avoid misdiagnosis as granulomatous inflammation.

[A case of high grade astrocytoma arising in the hand area of precentral gyrus].

A 23-year-old man presented with the right upper monoparesis. The right little finger paresis was apparent at first, and ring finger two weeks later, and middle, index, thumb were simultaneously four weeks later. Then the monoparesis gradually progressed to the proximal upper limb. Magnetic resonance imaging showed a small lesion at the knob of the left precentral gyrus. The lesion was low-intensity on T1-, and high-intensity on T2-weighted images, and clearly detected on high-intensity on FLAIR images, but showed no enhancement by gadolinium-diethylenetriamine pentaacetic acid (Gd-DTPA). Angiography and thallium scintigraphy showed no remarkable findings. Proton MR spectroscopy demonstrated lower N-acetylaspartate (NAA) and higher choline (Cho) level compared to the contralateral cortico-subcortical area. Diffusion weighted images demonstrated low apparent diffusion coefficient (ADC) value and high intensity on b = 1,000. To clarify the diagnosis of the lesion, we performed open biopsy by using the neuronavigation system to detect the lesion accurately and minimize the biopsy. Histological examination revealed an high grade astrocytoma with high MlIB-1 index over 30%. The progressive symptoms were due to highly infiltrative and proliferative nature of the tumor arising in the focal hand area of the primary motor cortex, according to the homunculus. We discuss herein the neuroimagings of the case that was considered to be in the initial stage of a malignant tumor.

Myositis ossificans of the temporal muscle as a primary scalp tumor. Case report.

A 38-year-old woman presented with a rare case of myositis ossificans in the temporal muscle manifesting as left temporal scalp mass with mild pain. The mass was elastic-hard and seemed to be located in the temporal muscle. Magnetic resonance imaging revealed a heterogeneously enhanced mass in the muscle. The tumor was resected. The histological diagnosis was myositis ossificans. The clinicopathological features of scalp myositis ossificans may mimic other soft tissue tumors, requiring care for the differential diagnosis.