For safe and reliable cerebral aneurysm clipping surgery, clean bloodless operative fields combined with stable and precise micro scissor manipulation are necessary. The surgeon must use both hands simultaneously and constantly visualize the best angle before proceeding.
  One of the most basic and important things to know is that the tips of the clip should be kept in sight continuously until the clips are closed. Accordingly, we propose a “blading technique” to visualize clip blade tips by 3-dimensional applier—where clip movement to keep in touch with the aneurysm is performed in combination with the complementary movement of the suction device in the opposite hand. Before trying to detach adhering vessels to the aneurysm, the surgeon should think through the necessity, because clipping is frequently accomplished using various manipulation techniques while vessel adhesion remains intact. Finally, we show basic clipping manipulation techniques.

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  The basic technique for endovascular treatment of intracranial aneurysm is a simple method requiring a single microcatheter and a long enough detachable coil for the coil embolization. Key factors for technical success are stability of the microcatheter based on the direction of the parent artery in relation to the aneurysm. Additionaly, the appropriate selection of framing, filling and finishing coils is another important factor. If adjunctive techniques are required, balloon and or stent assisted methods are available. But in most instances, the simple method will suffice and is therefore the most important and basic strategy for endovascular treatment of intracranial aneurysms.

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  Carotid endarterectomy (CEA) is recommended in symptomatic and asymptomatic patients with severe carotid artery stenosis. CEA therefore is an essential surgical technique for neurosurgeons to master. In this paper, I provide an outline of which CEA technique is to be used according to the anatomical findings, including how to dissect the distal internal carotid artery in the instance of high position stenosis. Since carotid patch angioplasty is the preferred technique for primary closure, I therefore also describe in detail how to perform patch angioplasty.

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  Deep bypass surgeries usually include the M2 portion of the middle cerebral artery, the A2-A4 portion of the anterior cerebral artery, the superficial cerebellar artery (SCA) and the posterior cerebral artery (PCA) as a recipient. These bypasses are relatively infrequent, but often essential to treat aneurysms or ischemic diseases of the corresponding arteries. The author describes basic techniques and tips of these deep bypass surgeries.
  Since 1998, the author experienced 80 such cases. Important common techniques include drilling of the bone protrusion at the edge of the craniotomy as much as possible to reduce retraction of the brain, wide opening of subarachnoid fissures and detachment of the recipient artery from arachnoid trabeculae so that the recipient can be manipulated in a shallow space without blood, and meticulous anastomosis avoiding any incompleteness. A double insurance bypass should precede the bypass to the M2. Augumented with these tips, the anastomosis itself can be performed using the same basic techniques employed in more superficial bypass surgery.
  Case 1 : A giant symptomatic internal carotid artery aneurysm at the cavernous portion was treated with a double insurance bypass to the M4 followed by a vein graft bypass to the M2 and parent artery occlusion. Case 2 : A partially thrombosed large aneurysm of the right A3 portion was treated with an A3-A3 bypass using a saphenous vein interposed graft followed by trapping of the parent artery (A3) just proximal and distal to the aneurysm. Case 3 : A case with basilar artery tandem occlusion causing cerebellar infarction was treated with a superficial temporal artery (STA)-SCA and PCA (posterior temporal artery) double bypass. Case 4 : A giant basilar trunk aneurysm compressing the brainstem to cause dysarthria and hemiparesis was treated with an STA-short vein graft-PCA bypass followed by clip occlusion of the basilar artery just proximal to the anterior inferior cerebellar artery, which originates from near the proximal neck of the aneurysm.
  Basic techniques and tips of deep bypasses have been described on the basis of 80 cases with aneurysms or ischemic diseases in the posterior circulation territory. Creating a wide and shallow working space would be the single most important step for successful deep bypass surgeries.

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  Skull base approaches using temporal bone drilling are mandatory approaches for not only cerebellopontine angle tumors and skull base tumors, but also in clipping or bypass for posterior fossa lesions. The author selected the surgical approaches for 1,322 cerebellopontine angle tumors, and used three types of mastoidectomy and two types of combined transpetrosal approaches to avoid the risk of sigmoid sinus injury and losing the hearing function. In this article, skull base approaches, particularly the combined transpetrosal approach are described from a practical aspect using 3D images.

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  Surgical approaches to the degenerative diseases such as cervical spondylosis or ossification of the posterior longitudinal ligament of the cervical spine include anterior arthrodesis and posterior decompression with or without fusion. Cervical laminoplasty was first described by Hattori, et al in 1973, and was getting the popularity as a typical posterior approach. This technique can yield a reasonable outcome as good as that of laminectomy with the advantage of avoiding total removal of spino-laminar complex. In this technique, a spacer is generally used to maintain the expanded spinal canal. Although apacerum has been most widely used as a spacer, complications derived from this material were reported. A novel titanium spacer called “Laminoplasty Basket” was lately introduced to compensate for the deficits of apacerum. In this paper, we describe surgical technique of less-invasive cervical laminoplasty using “Laminoplasty Basket” under an operating microscope.

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  We report a case of localized convexity hypertrophic pachymeningitis (HP) associated with aortitis. HP is considered to be one type of IgG4-related systemic disease as well as aortitis.
  A 38-year-old man with aortitis was admitted to our department due to generalized convulsive seizures. MRI revealed a localized mass like thickening of the convexity dura mater resembling meningioma. Because MRI showed rapid growth of the mass, diagnostic removal of the mass was performed to rule out the malignant tumor. Pathological examination showed hyalinization and fibrillation with infiltration of lymphocytes and IgG4-positive plasma cells. These findings suggest that our case is an IgG4-related systemic disease.
  However several combinations of IgG4-related diseases have been reported, reports of HP associated with aortitis are rare. In addition, this is the first case of localized convexity HP. We propose that resection of a symptomatic localized lesion is considered to be a therapeutic alternation for HP.

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