The surgical strategy for benign brain tumors should consider preserving brain functions. During pre- and intraoperative planning, the best surgical approach must be chosen based on tumor location and brain functions. It is now possible to visualize the localization of various brain functions using various imaging modalities, such as anatomical images for depicting the motor cortex or cranial nerves, diffusion tensor images for predicting white matter and functional MRI or a magnetoencephalogram. A three-dimensional fusion image that integrates functional and anatomical images is useful to understand functional localization before surgery and consider the surgical approach. Moreover, during surgery, it is important to validate the preoperative mapping of functional images with findings from intraoperative electrophysiological monitoring using a surgical navigation system. This article outlines the basic information, interpretation, and limitations in depicting the localization of brain function using anatomical images and depicting various functions of the white matter using diffusion tensor tractography and a surgical navigation system.

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  Even with the wealth of recent advances in surgical equipment and techniques, the surgical excision of craniopharyngiomas remains challenging due to their anatomical location and proximity to critical neurovascular structures. Although various surgical approaches to remove craniopharyngiomas have been described, including the pterional, orbitopterional, orbitozygomatic, transbasal subfrontal, frontobasal interhemispheric, and transnasal transsphenoidal, designating the optimal surgical approach remains controversial. In this article, we presented our sub-classification of craniopharynigiomas based on the anatomical location of the tumor. In addition, the most appropriate surgical approach to the lesion is discussed for these anatomical sub-classifications.

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  In acoustic neuroma surgery, preservation of facial and/or hearing functions is desired when tumor resection is required. Today, stereotactic radiosurgery or radiotherapy has become a standard alternative treatment ; therefore, surgical indication is becoming even more stringent. However, unification or standardization of the surgical indication for acoustic neuromas is difficult because each surgeon has different surgical skills, experience, surgical policy, and circumstances for surgery. Commonly consented surgical indications for acoustic neuromas are : a large tumor that is oversize for application of stereotactic radiation therapy, cystic tumor, rapidly growing tumor, and a tumor for which consideration is given to surgical hearing preservation in a young patient. The important key elements to achieve good surgical results are : a lateral suboccipital retrosigmoid approach, a surgical policy that does not always adhere to total removal, continuous facial nerve monitoring, full and sufficient opening of the posterior wall of the internal auditory canal, 7 gates of surgical resection, piercing and lifting a tumor with a dissector, and techniques for hemostasis.

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  The functional prognosis for deep-seated meningiomas is mostly dictated by the approach chosen and the dissection technique employed to remove tumor tissue from deep veins, cranial nerves and the brainstem. Accordingly, in this study among a consecutive 293 meningioma operations, the incidence, location, preservation rate of cranial nerve function, and the most appropriate approach selection for deep-seated meningiomas were retrospectively analyzed. The rate of vision improvement was 89% in 36 cases with visual dysfunction, the olfaction preservation was 93% in 30 cases operated via a basal interhemispheric approach, and hearing rate improvement was 44% in 9 cases with hearing disturbances. In order to determine the most appropriate approach to gain direct observation and secure dissection, detailed neuro-imagings including 320-row area detector CT, preoperative embolization of feeders from the internal carotid artery, and a thorough understandings of the biological behavior and pathology of the tumor-brain interface are important. Finally, after due delligence, it may become apparent that a multi-staged operation and/or Simpson Grade IV surgery might be a good alternative choice.

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  With the recent advances in technology, the role of radiation therapy is increasing in the treatment of benign brain tumors. In this article, charactristics and potentials of various high-technology radiotherapy modalities and machines are discussed. Gammaknife and cyberknife treatment can minimize irradiation to normal brain tissues, while tomotherapy and new linac-based image-guided radiotherapy (IGRT) machines can produce better dose distribution in the tumor. Nevertheless, all these modalities yield acceptable dose distribution for the treatment of benign brain tumors. One important issue in choosing a new radiation modality is the dose fractionation schedule.
  Gammaknife treatment is usually completed in one fraction, while any fractionation schedule is available with tomotherapy and new linac-based IGRT machines. The optimal dose fractionation remains unclear for benign brain tumors, and future studies are expected to clarify the issue. Then, the optimal radiation modality would become clearer.
  Using stereotactic irradiation or intensity-modulated radiation, long-term local control rates of over 90% have been reported for relatively small (<10 cm³) benign brain tumors (acoustic neuroma, craniopharyngioma, pituitary adenoma and meningioma). However, local control rates decrease with an increase in tumor size. Therefore, optimal radiation dose and fractionation schedule should be further investigated, especially for tumors with a large volume. In the future, stereotactic proton therapy and intensity-modulated proton therapy are expected to become popular, with the further development of particle therapy technologies.

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  Overall survival time (OS) and progression-free survival time (PFS) are generally used as endpoints in clinical trials involving malignant brain tumors including gliomas and lymphomas. The clinical manifestation of greatest concern in patients with malignant brain tumors such as glioblastoma is a decrease in function due to neurological deterioration that could hamper activities of daily life. Evaluation of the improvement in patient quality of life is necessary in addition to the evaluation of survival time, as the number of long-term survivors increases. However, research on the health-related quality of life (HRQOL) and cognitive function of patients after treatment with surgery, radiotherapy, and chemotherapy for malignant brain tumors is insufficient. To enhance research on HRQOL in malignant brain tumor patients, the methods and shortcomings of HRQOL evaluation are reviewed and discussed.

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  Concerning the prevention of deep vein thrombosis (DVT) in patients after stroke, elastic stockings (ES) and noninvasive screening for DVT are recommended. Therefore, we evaluated the incidence of DVT in patients suffering from acute stroke, using ultrasonography in three hospitals for ten years.
  According to this study, nine patients (30%) had DVT (6 proximal DVT and 3 calf DVT) out of thirty patients not using ES. However, ninety-seven patients (9.1%) had DVT (27 proximal DVT and 70 calf DVT) out of one thousand and sixty-three patients using ES. The use of ES made the incidence of proximal DVT drop from 20% to 2.5% with statistical significance. Although the incidence of DVT within the three hospitals was not significantly different, the incidence of calf DVT was higher in the hospital with higher numbers of ultrasonography and the incidence of proximal DVT is higher in the hospital with fewer nurses. Furthermore, from fifty-one patients out of seventy patients with calf DVT, repeated ultrasonography showed that the calf DVT disappeared completely in thirty-four patients (66.7%) and proximal extension of calf DVT was not observed at all.
  Although sensitivity of calf DVT depends on the diagnostic technique, we think that it is almost harmless. The important thing when screening is not to overlook proximal DVT.

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  A 38 year-old female presented with progressive right hearing disturbance that had persisted for 4 years. A CT scan showed a partially enhanced lesion in the right temporal bone invading the cochlea, the superior semicircular canal and a part of the temporomandibular joint. Her facial nerve function was intact. A diagnosis of chondroblastoma was made by transmeatal biopsy. A subtemporal approach was used to surgically remove the tumor. The dura mater was not invaded by the tumor and the surgical removal was limited thereby preserving facial nerve function. However, she developed mild facial nerve palsy postoperatively but it resolved within a year. The final pathological diagnosis was chondroblastoma. We report this case because chondroblastoma of the temporal bone is extremely rare and the recurrence rate is reported not to be low so close follow-up observation is required.

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