We described the microsurgical anatomy of the lateral part of the foramen magnum and the transcondylar fossa approach (TCFA). The TCFA provides a wide and shallow operative field in the lateral part of the medulla oblongata at the level of the jugular foramen. Furthermore, the wide dissection of the unilateral cerebello-medullary fissure is necessary to retract the cerebellum safely and manage the lesion in the wide operative field.

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  Occipito-cervical (O-C) fusion is a well established bone surgery procedure. At the planning and operation of the O-C fusion, bone biology, biomechanics, and cervical alignment should all be carefully taken into consideration. In this report, I first describe the characteristics of and pitfalls to avoid in the placement of the anchors on the occiput, C1 and C2. To prevent the vascular injury, the most serious complication of the O-C fusion, a thorough understanding of the variation of the vertebral artery and cranial sinus is paramount. Precise evaluation of the individual course of each using preoperative CT angiography and CT venography is essential. The impact of the O-C2 fixation malalignment on the postoperative dysphagia, another serious complication of the O-C fusion, is also discussed.

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  As head and neck surgeons, we treat diseases between the skull base and the upper mediastinum, developing numerous surgical skills and techniques in the course of our work. Here we report on the neurosurgical anatomy and basic surgical techniques on the anterior craniocervical junction from the viewpoint of head and neck surgeons. Three different approaches are evaluated and discussed in detail.
  Adequate anterior approach to the craniocervical junction across the infratemporal fossa is beneficial for neurosurgeons. We begin with describing the total maxillectomy procedure. Preserving important nerves and vessels, excising appropriate muscles, and guarding against bleeding, we can minimize morbidity and damage consequent upon this approach.
  Second, we describe the transcervical approach following neck dissection. Combining the mandibular swing, one can access the parapharyngeal space, then after get close to the anterior craniocervical junction. This area contains many vital nerves, vessels, and other important anatomical structures : the surgeon must take care to avoid injuring them and preserve the function of the lower cranial nerves in order to preserve swallowing function. Above all, preservation of the internal carotid artery is the most essential factor for overall prognosis.
  Third, we explain subtotal temporal bone resection to approach the craniocervical junction from behind, combined with skull base surgery. Careful initial neck dissection is requisite to preserve the nerves and vessels. With a neurosurgeon in one arm performing craniotomy, an adequate margin of the middle ear cavity is gained and complete boney dissection can be performed. Facial nerve repair with the hypoglossal nerve is sometimes required. Occasionally, special reconstruction using free flap transfer is needed.
  Precise neurosurgical anatomy and basic techniques in head and neck surgery are helpful for neurosurgeons undertaking craniocervical junction surgery to know. These techniques provide excellent access to the craniocervical junction and help avoid injury to important nerves and vessels (as well as protect the lower cranial nerves). Coordination between head and neck surgeons and neurosurgeons would be beneficial in approaching these areas more safely.

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  It is difficult to resect a lumbar midline disc herniation, especially a lumbar midline huge disc herniation, using so-called Love procedure. Various surgical complications, such as root injury due to excessive retraction or dural tears as a result of blind operations have been reported. We herein describe four surgical methods for a lumbar midline huge disc herniation, which we have been performing for seven years.
  In this series, we defined a lumbar midline huge disc herniation as a herniated mass having the following two characteristics.
  1) A ratio of the maximum diameter of the mass to the diameter from posterior surface of the vertebral column to the dorsal side of the dural sac >70%.
  2) A C-shaped dural sac formed due to the compression from the herniated mass.
  We retrospectively investigated 540 patients who underwent an operation for a lumbar disc herniation in Spinal Disorders Center, Fujieda Heisei Memorial Hospital from January 2005 to September 2012, and identified 12 patients (nine males, three females) meeting our definition of a lumbar midline huge disc herniation.
  The surgical methods used were : unilateral partial hemilaminectomy (five cases), bilateral laminectomy (five cases), a transforaminal approach with pedicle screw fixation (one case) and a transdural approach (one case).
  Each option has advantages and disadvantages. An appropriate surgical option should be chosen after evaluating the patient in terms of lumbar level, deviation of dural sac and cauda equine rootlets and the possibility of adhesion with the dura mater.

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  Careful medical interviewing is crucial for the diagnosis of epilepsy. However, the number of available epileptologists is not adequate to serve the cities in Japanese regional areas. This study assessed the use of a video-conferencing system to hold a remote epilepsy clinic with the cooperation of a tertiary epilepsy center and a local public hospital in an area devastated by the Great East-Japan Earthquake and tsunami. The video-conferencing system established protocols to ensure the protection of personal information on the internet.
  Epileptologists in Tohoku University Hospital (tertiary epilepsy center) interviewed outpatients in the Kesennuma City Hospital (local public hospital) via the video-conferencing system. Medications and physical examinations were performed at the Kesennuma City Hospital based on the recommendations of the epileptologists. Nine patients received consultations via the remote epilepsy clinic from March 2012 to February 2013. Treatment strategies were established in 4 patients with epilepsy. Differential diagnosis was established in the other 5 patients with episodes of loss of consciousness. The interviews were successfully performed with the same quality as face-to-face interviews. Such remote clinics using the video-conferencing system will be valuable for medical support and education in medically underserved areas. However, the current health insurance system does not cover the provision of such telemedicine services in Japan.

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  It is widely reported that complete tumor resection is the most certain method for successful radical craniopharyngioma resection. However, radical resection and endocrinic function preservation are often opposing goals in craniopharyngioma surgery. Also, as for the context of “total removal”, there are no reports that clearly examine the complete total removal method with pathological specimens. Therefore we discuss radical resection that has a high curative rate from the view point of long-term prognosis in our experiences.
  Between 1991 and 2012, 57 patients underwent surgery for craniopharyngioma in 71 instances at our institution. The follow-up period ranged from 6 months to 21 years (mean 8.4 years). We aimed to remove the tumor totally in almost all cases with a combined supra-and infra-chiasmatic approach or orbitozygomatic multi-trajectory approach. Although the surgical approach should be deliberately selected in order to obtain a better view of the tumor origin and to preserve this axis anatomically priority should be given to radical resection when functional preservation is considered to be impracticable.
  For many of the non recurrent cases we partially perforated the hypothalamus and removed the tumor totally with the pituitary stalk and gland in recent years, but in a few of the non recurrent cases we removed the tumor totally while preserving the pituitary stalk and gland. So almost all of the non recurrent cases required hormone replacement postoperatively independent of whether we preserve the pituitary stalk and gland or not. The feasibility of functional preservation of the hypothalamic-pituitary axis is determined primarily by the exact site of tumor origin, i. e. proximal or distal to the hypothalamus-pituitary stalk junction. Finally for the purpose of attaining truly radical resection of the tumor, intraoperative frequent and frozen histopathological examination is mandatory to confirm that accurate surgical margins have been obtained.

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  It is important to determine the site of rupture in subarachnoid hemorrhage (SAH) patients associated with multiple cerebral aneurysms.
  However, an unusual radiological presentation of subarachnoid hemorrhage can result in the misdiagnosis of the rupture site.
  A 32-old-woman had sudden onset of severe headache and was visited our hospital.
  CT scan showed thin SAH in the right sylvian fissure and a small blood clot located in front of the brainstem.
  CT angiography (CTA) showed a right internal carotid-posterior communicating (IC-PC) artery aneurysm and an aneurysm of a fenestrated basilar (FBA) artery. It was difficult to determine the precise bleeding site preoperatively.
  Because of the predominant SAH in the right sylvian fissure on CT scans, the origin of the hemorrhage was suspected to be a right IC-PC artery aneurysm, and clipping was performed.
  However, hemorrhage recurred four days after clipping. Cerebral angiography suggested a diagnosis of hemorrhage from an FBA artery aneurysm. Endovascular embolization was performed, and both episode of SAH were considered to be attributed to this aneurysm. Postoperative course of the patient was uneventful.
  Misjudgment may result in disastrous postoperative rebleeding from the untreated but true ruptured lesion. Correct diagnosis of ruptured aneurysm with confirmation of aneurysm location and proper therapeutic treatment are directly connected to prognosis.
  It is therefore necessary to perform detailed evaluation of a suspected rupture site and to select the appropriate treatment.

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  We reported a tragic case of intracranial hypotension before. We suggested then that when patients have an associated disturbance of consciousness, they should be rapidly and appropriately treated. However, treating these cases may be difficult, because most cases present with subdural hematoma (SDH). In such case it is difficult to determine whether the cause of the disturbance of consciousness is cerebrospinal fluid (CSF) hypovolemia or the underlying SDH. Therefore, we decided on a flexible course of treatment suitable for each scenario. This course of treatment is based on : 1) diagnosis using only head contrast-enhanced magnetic resonance imaging (MRI) views and initiation of treatment ; 2) performing drainage according to the thickness of the SDH ; and 3) an epidural blood patch (EBP) is placed at the L₁-L₂ level. We report three cases with consciousness disturbances. Each of three cases was treated with our flexible treatment ; drainage was performed for one case, and an EBP was placed in all cases. Good results were obtained in all cases.

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