Primary Intracranial Spindle Cell Sarcoma, -Mutant, with Amplification Diagnosed on the Basis of Extensive Molecular Profiling.

Primary intracranial spindle cell sarcoma is an extremely rare mesenchymal tumor, the molecular pathogenesis of which is poorly understood. Because of the lack of specific markers, diagnosis sometimes relies on ruling out all possible differential diagnoses, often making it difficult to reach a definitive diagnosis. In this case study, we report a 69 year-old female patient for whom the integration of multi-layered molecular analyses contributed to making the diagnosis.

[Malignant Transformation of Cerebellopontine Angle Epidermoid Cyst:A Case Report].

Intracranial epidermoid cysts are benign cystic lesions that typically exhibit slow growth. Their malignant transformation into squamous cell carcinoma is rare. We report a 77-year-old woman who was admitted to our hospital because of a near-drowning incident due to a seizure sustained in her bathtub.

Resection of a lateral supratentorial endodermal cyst complicated by postoperative seizures: A case report.

Background: Endodermal cysts are uncommon cystic lesions usually located at the ventral aspects of the spine. A lateral supratentorial location of such cysts is extremely rare. A unique case of a lateral supratentorial endodermal cyst that required surgical intervention due to uncal herniation, complicated with postoperative seizures, is presented.

Anterior interhemispheric approach for clipping of subcallosal distal anterior cerebral artery aneurysms: case series and technical notes.

Distal anterior cerebral artery (DACA) aneurysms are rare, accounting for 1-9% of all intracranial aneurysms. Previous systematic reviews have highlighted that given the markedly increased incidence of major complications after endovascular treatment, microsurgical clipping is the more attractive treatment option with generally excellent clinical outcomes. Subcallosal DACA aneurysms constitute a rare subset of these aneurysms, requiring special anatomic considerations-particularly with regard to the approach.

Retrosigmoid Intradural Suprajugular Approach to Jugular Foramen Tumors with Intraforaminal Extension: Surgical Series of 19 Cases.

Objective: The intraforaminal component of jugular foramen tumors is difficult to access surgically, as it requires complex approaches for radical removal and leads to a high recurrence due to residual tumor. The retrosigmoid suprajugular approach, intradural drilling of the roof of the jugular foramen, has been recently proposed for removal of such intraforaminal component without sacrificing the sigmoid-jugular venous system or requiring additional approaches. This study presents our experience with this approach and introduces the use of intraoperative continuous vagus nerve monitoring.

Intramedullary and intratumoral hemorrhage in spinal hemangioblastoma: Case report and review of literature.

Background: Intramedullary hemorrhages involving spinal hemangioblastomas are rare. They are frequently associated with devastating neurologic outcomes, despite with emergent surgical intervention. Here, we presented an example of an intramedullary hemorrhage occurring in a spinal hemangioblastoma, where the patient markedly improved with surgery.

The Method for Placement of an Intraoperative Continuous Facial Nerve Stimulating Electrode in Acoustic Neuroma Surgery: Technical Note.

Preservation of facial nerve (FN) function is the most important goal in acoustic neuroma (AN) surgery. We have been using intraoperative continuous facial nerve monitoring (ICFNm) of evoked electromyography during AN surgery. ICFNm is very useful, and we can identify the real-time functions of the FN.

Hypervascular Vestibular Schwannomas: Clinical Characteristics, Angiographical Classification, and Surgical Considerations.

Background: There is a rare type of vestibular schwannoma, scarcely discussed in the literature, known as a hypervascular vestibular schwannoma (HVS).

Objective: To evaluate its biological characteristics, angiographical classification, surgical outcomes, and the significance for surgical consideration, using a large series of this clinical entity.

Methods: The definition for HVS in this study was the tumor stain from the vertebrobasilar system (VBS) in angiography.

Long-Term Patency of Posterior Auricular Artery-Middle Cerebral Artery Bypass for Adult-Onset Moyamoya Disease: Case Report and Review of Literature.

Background: Direct extracranial-intracranial (EC-IC) bypass is one of the fundamental techniques to prevent recurrent stroke in patients with adult-onset ischemic moyamoya disease. When the standard superficial temporal artery (STA) cannot be used for a graft, the posterior auricular artery (PAA) can be a potential surrogate graft.

Case Description: In this article, the authors reported a 34-year-old female patient suffering from ischemic moyamoya disease.

Medical Engineering and Microneurosurgery: Application and Future.

Robotics and medical engineering can convert traditional surgery into digital and scientific procedures. Here, we describe our work to develop microsurgical robotic systems and apply engineering technology to assess microsurgical skills. With the collaboration of neurosurgeons and an engineering team, we have developed two types of microsurgical robotic systems.

Dorsal displacement of the facial nerve in acoustic neuroma surgery: clinical features and surgical outcomes of 21 consecutive dorsal pattern cases.

In acoustic neuroma surgery, the facial nerve (FN) course varies among patients, but a dorsal pattern is rarely observed. We retrospectively reviewed and classified 556 acoustic neuromas operated on via a lateral suboccipital retrosigmoid (LSO) approach into two groups: dorsal (group D) and non-dorsal (group ND). The clinical features and outcomes including functional preservation of the FN, the extent of tumor resection, and the retreatment rate were compared.

[An Endovascular Approach for Ruptured Aneurysms of the Basilar Trunk Perforating Artery].

Aneurysms of the basilar trunk perforating artery are rarely described in the literature. Only 13 cases have been reported previously. The recommended treatment for these aneurysms is usually direct surgery such as microsurgical clipping or proximal trapping;endovascular therapy is not preferred because of difficulty to access the aneurysm.

Assessing Microneurosurgical Skill with Medico-Engineering Technology.

Objectives: Most methods currently used to assess surgical skill are rather subjective or not adequate for microneurosurgery. Objective and quantitative microneurosurgical skill assessment systems that are capable of accurate measurements are necessary for the further development of microneurosurgery.

Methods: Infrared optical motion tracking markers, an inertial measurement unit, and strain gauges were mounted on tweezers to measure many parameters related to instrument manipulation.

Clinical features of vestibular schwannomas in patients who experience hearing improvement after surgery.

Postoperative improvements in hearing in patients with vestibular schwannoma are extremely rare. We reviewed nine cases retrospectively to investigate the clinical features of these cases. Hearing improvement was defined as an improvement in hearing class according to American Academy of Otolaryngology-Head and Neck Surgery (AAO-HNS) criteria.

Perioperative management of catecholamine-secreting glomus jugulare tumors.

To treat patients with a catecholamine-secreting glomus jugulare tumor, perioperative management is important. Perioperative catecholamine hypersecretion causes severe problems in the treatment of a catecholamine-secreting glomus tumor. Therefore, a precise therapeutic strategy and perioperative management are required through collaboration of the endocrinology, anesthesiology, and endocrine surgery departments .

Cavernous sinus angioleiomyoma: case report and review of the literature.

Cavernous sinus angioleiomyoma (ALM) is extremely rare. Only three cases have been reported to be cavernous sinus ALM, and very few reports described characteristic findings for intracranial ALMs in detail. We report a new case of cavernous sinus ALM, with detailed information on the clinical presentation, radiology, pathology, and surgical approach.

Development of a new compact intraoperative magnetic resonance imaging system: concept and initial experience.

Background: Magnetic resonance imaging (MRI) during surgery has been shown to improve surgical outcomes, but the current intraoperative MRI systems are too large to install in standard operating suites. Although 1 compact system is available, its imaging quality is not ideal.

Objective: We developed a new compact intraoperative MRI system and evaluated its use for safety and efficacy.

Determination of the keyhole position in a lateral suboccipital retrosigmoid approach.

Appropriate placement of the keyhole at the transverse and sigmoid sinus (T/S) junction is important for performance of safe and accurate lateral suboccipital craniotomy with minimum bone loss. Here, we report a method for predicting the position of the T/S junction and investigate the relationship between the T/S junction and asterion. The subjects were 88 patients treated surgically via a lateral suboccipital approach.

Hydrocephalus associated with vestibular schwannomas: perioperative changes in cerebrospinal fluid.

Background: Cerebrospinal fluid (CSF) protein levels are known to increase in patients with vestibular schwannomas (VS) with concomitant hydrocephalus, however the only information available on perioperative changes in CSF in these patients comes from case reports. Here, we investigated the relation between CSF protein and hydrocephalus in a large series of patients undergoing resection of VS.

Method: We classified 376 patients undergoing resection for VS at our institute into two groups, namely VS and no hydrocephalus (control, n = 319) and VS with concomitant hydrocephalus (n = 57), and compared clinical parameters.

Prognosis of tinnitus after acoustic neuroma surgery--surgical management of postoperative tinnitus.

Objective: Tinnitus is a bothersome symptom for patients with acoustic neuroma. We studied the possibility of surgical control of postoperative tinnitus associated with acoustic neuroma.

Methods: Postoperative changes and prognosis of tinnitus were studied in 367 patients treated surgically via a lateral suboccipital retrosigmoid approach.

Master-slave robotic platform and its feasibility study for micro-neurosurgery.

Background: Microsurgery is a widely performed process in neurosurgery. However, it is difficult for surgeons because manipulating small and long instruments under a microscope often restricts dexterity. Hand tremors are also an issue, as the accuracy required for microsurgery is very high.

Preoperative evaluation of unruptured cerebral aneurysms by fast imaging employing steady-state acquisition image.

Background: In aneurysm surgery, understanding the microanatomy around the aneurysm such as perforating arteries and cranial nerves is mandatory.

Objective: To assess the usefulness in determining the microanatomy around the cerebral aneurysms by the use of fast imaging employing steady-state acquisition (FIESTA) images of magnetic resonance imaging preoperatively, in addition to computed tomography and digital subtraction angiography.

Methods: Between October 2006 and June 2009, 123 patients with 140 unruptured cerebral aneurysms were treated in our institution.

Intraoperative continuous monitoring of evoked facial nerve electromyograms in acoustic neuroma surgery.

Background: Preservation of facial nerve function is one of the most important goals in acoustic neuroma surgery. We have been using intraoperative continuous monitoring of evoked facial nerve electromyograms (EMGs) since 1997 in acoustic neuroma surgery. We therefore investigated surgically treated patients to clarify the usefulness of this monitoring, and to determine safety criteria for preserving facial nerve function.