Choroid Plexus Papilloma in the Fourth Ventricle Associated with Pheochromocytoma: A Case Report.

We report for the first time a case of choroid plexus papilloma (CPP) of the fourth ventricle associated with adrenal pheochromocytoma. A large tumor was found in the fourth ventricle of a 24-year-old man who presented with symptoms of increased intracranial pressure due to obstructive hydrocephalus. A systemic search revealed that the patient also had an asymptomatic left adrenal tumor.

Cortico-cortical evoked hemodynamic responses in human language systems using intraoperative near-infrared spectroscopy during direct cortical stimulation.

Background: Understanding of cortico-cortical activity in eloquent areas intraoperatively is crucial for neurosurgical procedures. Here, we used intraoperative near-infrared spectroscopy (iNIRS) during direct cortical stimulation as a robust tool to better understand the cortico-cortical connectivity in language systems.

Methods: We applied iNIRS to 3 patients who underwent epilepsy surgery due to lesions (cavernous angioma, epidermoid cyst, and low-grade glioma) located in language areas.

Mobile spinal enterogenous cyst resulting in intermittent paraplegia in a child: case report.

The authors report the case of a mobile spinal enterogenous cyst in a 2-year-old boy, who was admitted to the hospital several times for intermittent paraplegia. Magnetic resonance imaging and CT revealed an isolated cyst in the lumbar spinal canal. The symptoms were caused by transient myelopathy of the conus medullaris and radiculopathy of the cauda equina due to the changing size and location of the cyst.

Drainage patterns of the superficial middle cerebral vein: Effects on perioperative managements of petroclival meningioma.

Background: Although the superficial middle cerebral vein (SMCV) usually connects with the cavernous sinus, there are several anatomical variations. We determined whether differences in SMCV drainages patterns affected the perioperative management of petroclival meningioma.

Methods: The subjects included 17 patients (4 men; 13 women) who underwent resection of a petroclival meningioma.

Free-running EMG monitoring during microvascular decompression for hemifacial spasm.

Background: The aim of this work is to determine if free-running electromyography (frEMG) can detect activity before and after microvascular decompression (MVD) treatment for hemifacial spasm (HFS), and to evaluate correlations of frEMG findings with abnormal muscle responses (AMRs) or facial motor-evoked potentials (FMEPs).

Methods: To elicit nerve responses while carrying out frEMG recording before and after MVD, saline, a lactic solution, or artificial cerebrospinal fluid was injected onto the root exit zone of the facial nerve.

Results: Significantly higher frEMG activity was observed following saline injection than for the other solutions (p < 0.

Pharyngeal Motor Evoked Potential Monitoring During Skull Base Surgery Predicts Postoperative Recovery from Swallowing Dysfunction.

Objective: Monitoring pharyngeal motor evoked potential (PhMEP) with a modified endotracheal tube is useful for predicting postoperative swallowing dysfunction. However, the relationship between intraoperative PhMEP findings and recovery from postoperative swallowing dysfunction has not been clarified. The aim of this study was to determine whether PhMEP monitoring predicts swallowing dysfunction not only immediately after surgery but also in the postoperative recovery period.

Cortico-cortical activity between the primary and supplementary motor cortex: An intraoperative near-infrared spectroscopy study.

Background: The supplementary motor area (SMA) makes multiple reciprocal connections to many areas of the cerebral cortices, such as the primary motor cortex (PMC), anterior cingulate cortex, and various regions in the parietal somatosensory cortex. In patients with SMA seizures, epileptic discharges from the SMA rapidly propagate to the PMC. We sought to determine whether near-infrared spectroscopy (NIRS) is able to intraoperatively display hemodynamic changes in epileptic network activities between the SMA and the PMC.

Clinical factors predicting outcomes after surgical resection for sporadic cerebellar hemangioblastomas.

Objective: To determine whether various clinical factors are related to long-term outcomes of patients with sporadic cerebellar hemangioblastomas.

Methods: Subjects included 36 patients (19 men and 17 women) who underwent resection of sporadic hemangioblastoma in the cerebellum. Age at surgery ranged from 17-79 years (mean, 49.

Novel devices for intraoperative monitoring of glossopharyngeal and vagus nerves during skull base surgery.

Background: Swallowing disturbance is among the most burdensome complications suffered by patients with glossopharyngeal and vagus nerve involvement in lesions adjacent the jugular foramen. For monitoring these nerves, we have developed new devices that comprised four contacts adhering to the surface of the cuff of an endotracheal tube, with attachment the posterior pharyngeal wall. To determine whether these devices are useful for monitoring the glossopharyngeal and vagus nerves and predicting postoperative swallowing dysfunction in patients undergoing removal of skull base tumors involving these nerves.

Importance of awareness of the rhomboid lip in microvascular decompression surgery for hemifacial spasm.

Object: The authors adopted the infrafloccular approach for microvascular decompression (MVD) surgery to treat hemifacial spasm (HFS). The inferior portion of the flocculus is retracted to observe the root exit zone of cranial nerve (CN) VII between CN IX and the flocculus. During the procedure, the rhomboid lip, a sheetlike layer of neural tissue forming the lateral recess of the fourth ventricle, is sometimes encountered.

Interactive presurgical simulation applying advanced 3D imaging and modeling techniques for skull base and deep tumors.

Object: In this paper, the authors' goal was to report their novel presurgical simulation method applying interactive virtual simulation (IVS) using 3D computer graphics (CG) data and microscopic observation of color-printed plaster models based on these CG data in surgery for skull base and deep tumors.

Methods: For 25 operations in 23 patients with skull base or deep intracranial tumors (meningiomas, schwannomas, epidermoid tumors, chordomas, and others), the authors carried out presurgical simulation based on 3D CG data created by image analysis for radiological data. Interactive virtual simulation was performed by modifying the 3D CG data to imitate various surgical procedures, such as bone drilling, brain retraction, and tumor removal, with manipulation of a haptic device.

[Intraoperative monitoring of motor evoked potentials during glioma removal].

Objective: To determine whether motor evoked potentials(MEPs)provide reliable monitoring of the motor system during resection of gliomas in or adjacent to the motor cortex or pyramidal tract.

Materials And Methods: MEP recording was performed during 64 operations in 55 patients harboring gliomas. Intraoperative MEP findings were classified into 3 groups:Group A was defined as having no significant MEP changes, Group B as having reversible MEP changes(?50% amplitude decrease or loss), and Group C as having irreversible changes.

[Transcranial motor evoked potentials monitoring for cerebral aneurysm surgery].

Objective: To evaluate the usefulness of transcranial motor evoked potential(MEP)monitoring for aneurysm surgery.

Methods: Sixty-four patients undergoing aneurysm surgery were included in the study. We recorded MEP responses at craniotomy, when dissecting the aneurysm and surrounding tissue, after clipping, and during temporary clipping of the parent artery.

Monitoring of abnormal muscle response and facial motor evoked potential during microvascular decompression for hemifacial spasm.

Background: To determine whether the monitoring of abnormal muscle response (AMR) and facial motor evoked potential (FMEP) during microvascular decompression (MVD) for hemifacial spasm (HFS) might be useful for predicting the postoperative clinical course and final outcomes.

Methods: We analyzed 45 HFS patients who underwent both AMR and FMEP monitoring during MVD. Patients were divided into two groups on the basis of post-MVD disappearance (group AMR-A) or persistence (group AMR-B) of AMR.

[Three-dimensional images of petrosal veins for preoperative evaluation: four case reports].

Background: In the surgeries of the upper part of the cerebellopontine angle (CPA), the petrosal vein (PV) is an obstacle, and the resection of the PV sometimes causes postoperative complications such as cerebellar hemorrhagic infarction. On the other hand, it can be an anatomical landmark during the surgery. We have used three-dimensional (3D) CT images for preoperative evaluation.

Thrombosed giant aneurysm of the distal anterior cerebral artery treated with aneurysm resection and proximal pericallosal artery-callosomarginal artery end-to-end anastomosis: Case report and review of the literature.

Background: Giant distal anterior cerebral artery (DACA) aneurysms are extremely rare, with only 32 cases reported in the literature. Most giant DACA aneurysms have features that make standard neck clipping difficult, and bypass surgery is sometimes required, although this surgery was performed in only three reported cases. This report presents the fourth case treated with bypass surgery.

Three-dimensional visualization of neurovascular compression: presurgical use of virtual endoscopy created from magnetic resonance imaging.

Objective: To assess the usefulness of presurgical simulation of microvascular decompression (MVD) by virtual endoscopy (VE), a new tool to analyze three-dimensionally reconstructed magnetic resonance data sets in patients with trigeminal neuralgia or hemifacial spasm (HFS).

Methods: In 17 patients (10 with trigeminal neuralgia and seven with HFS) determined to be candidates for MVD, we performed presurgical simulation of MVD using VE. We used constructive interference in steady-state imaging and magnetic resonance angiography to obtain the original images.

[Facial nerve motor evoked potentials elicited by transcranial electrical stimulation for intraoperative monitoring].

Objective: To determine whether monitoring facial nerve motor evoked potentials (FNMEPs) elicited by transcranial electrical stimulation during skull base tumor surgery is useful for predicting facial nerve outcome.

Methods: We analyzed FNMEP findings in 31 patients with skull base tumor. Surgery was performed twice in 2 of the 31 patients because of tumor regrowth.

Etiopathological factors related to hydrocephalus associated with vestibular schwannoma.

Objective: We retrospectively analyzed various clinical factors to determine whether or not these factors are etiopathologically related to the development of hydrocephalus in patients with vestibular schwannomas.

Methods: There were 68 patients (29 men, 39 women) in this study who underwent resection of a vestibular schwannoma. The age at the time of surgery ranged from 19 to 76 years (mean age, 51.

[The utility of presurgical simulation of microvascular decompression by MR virtual endoscopy].

Objective: We conducted the present study to assess the utility of virtual endoscopy (VE) created by volume rendering of MR images in presurgical simulation for trigeminal neuralgia (TN) and hemifacial spasm (HFS).

Methods: In 12 patients (six with TN and six with HFS), we presurgically evaluated the anatomy of the cerebellopontine angle (CPA) region and simulated an appropriate surgical approach by VE of heavy T2-weighted imaging and MR angiography.

Results: The three-dimensional (3-D) relations of neurovascular structures in the CPA region were compatible between on-VE and on-the-intraoperative view in all patients.

Unusual giant cerebral venous varix associated with brain abscess: variant of hereditary hemorrhagic telangiectasia--case report.

A 35-year-old man suffered secondary generalized tonic-clonic convulsions due to a large brain abscess. Neuroimaging incidentally revealed another tumor-like lesion. Cerebral angiography confirmed that the lesion was an unusual giant venous varix associated with a high-flow pial arteriovenous fistula (AVF) and showed one more small arteriovenous malformation (AVM).

[Abnormal muscle response monitoring during microvascular decompression for hemifacial spasm and long term results].

Objective: There is some debate over the reliability of intraoperative abnormal muscle response (AMR) monitoring as an indicator of postoperative long-term outcome in patients with hemifacial spasm (HFS). We investigated whether AMR findings obtained during microvascular decompression reflect postoperative long-term outcome. MATERIAS AND METHODS: Subjects were 51 HFS patients who underwent AMR monitoring during surgery.

Transcranial imaging of audiogenic epileptic foci in the cortex of DBA/2J mice.

Exposure to intense sound stimuli induces audiogenic seizures in DBA/2J mice. We investigated cortical activities during sound stimulation using flavoprotein fluorescence imaging. Most DBA/2J mice had seizures during intense sound stimulation, with more than half surviving after seizures.

Short-term plasticity visualized with flavoprotein autofluorescence in the somatosensory cortex of anaesthetized rats.

In the present study, short-term plasticity of somatosensory neural responses was investigated using flavoprotein autofluorescence imaging in rats anaesthetized with urethane (1.5 g/kg, i.p.