Introduction: Skin incisions made for carotid endarterectomies (CEA) are mainly classified into longitudinal or transverse types. A wider operative field can be achieved with longitudinal incisions, whereas transverse incisions are more cosmetic. We retrospectively investigated the relationship between lesion length and skin incision length for CEA with transverse incisions.

Methods: We investigated 20 consecutive patients who underwent CEA at our institution and followed them for more than one year. Lesion length was measured on preoperative digital subtraction angiography or three-dimensional computed tomography. The skin incision length was extracted from the operative record.

Results: The minimum and maximum lesion lengths were 8.7 mm and 38.8 mm, respectively. The minimum and maximum skin incision lengths were 63 mm and 87 mm, respectively. Lesion dilatation was achieved, and no restenosis was observed in any cases. Transient peripheral facial nerve paresis was recognized in one patient (5%).

Conclusion: CEA using a transverse incision can be performed when the skin incision length is 30-50 mm longer than the lesion length. Transverse incisions are not only superior cosmetically, their use results in satisfactory surgical outcomes.

Here we report a novel method of exposing the anatomical structures in carotid endarterectomy (CEA) by adopting a simple technique to manipulate the fat tissue within the carotid triangle. A sheet of layered fat tissue is located in the carotid triangle. Since this tissue has no particular anatomical nomenclature, we call it the carotid fat pad (CFP). The CFP has a distinctive boundary against the surrounding structures. Its bottom end lies atop the carotid sheath. If the vascular-less anterior margin of the CFP is dissected and the entire CFP is turned toward the posterior, a less bloody surgical field can be achieved and more of the internal carotid artery becomes visible. We call this the Carotid Fat Pad Flip Method.

Whether partial resection of the rectal gyrus during anterior communicating artery (AcomA) aneurysmal clipping can cause cognitive dysfunction remains under debate. We examined this issue using data from patients with AcomA aneurysms who underwent partial (approximately 1 cm) subpial removal of the rectal gyrus during dissection of the aneurysmal complex. All procedures were performed by a single operator using the supraorbital keyhole approach. Sixty-three consecutive patients with AcomA aneurysms underwent aneurysmal clipping with rectal gyrus aspiration through the right (n=50) or left (n=13) side. Their Revised Hasegawa’s Dementia Scale (HDS-R) and Mini-Mental State Examination (MMSE) scores were assessed immediately preoperative and 3 months postoperative to evaluate their cognitive function. The Beck Depression Inventory (Beck) and Hamilton Depression Rating Scale (HAM) were also used to evaluate depression severity, which can interfere with executive function. No patient exhibited perforator infarctions or brain contusions postoperatively. The patients’ cognitive functions, according to the HDS-R and MMSE, were unchanged after surgery, whereas depression severity, according to Beck and HAM, was significantly improved after clipping surgery. Multiple linear regression analysis showed that the treated side was not a significant predictor of any psychological change. As long as perforator compromise does not occur and no contusions occur in the orbitofrontal cortex, partial resection of the rectal gyrus itself does not adversely affect cognitive function or depression.

The clipping of middle cerebral artery aneurysms is regarded as the basis of aneurysmal clipping surgery. In our institute, the concept of this operation has been clarified and standardized so that young surgeons can develop stable neurosurgical skills and strategies with a limited amount of surgical experience. These important points are summarized as follows: when dissecting the Sylvian fissure, retractors and sharp dissection should be used carefully and the fissure should be opened widely. When approaching an aneurysm, always proceed from the non-adhesion side to the aneurysm. In this report, we introduce these surgical concepts and verify the results of 63 cases operated by young surgeons. Two patients (3.2%) experienced ischemic complications related to surgery, but both were asymptomatic; none of the patients had deteriorated postoperative modified Rankin Scale scores. Thus, our operative concept is useful to ensure that middle cerebral artery aneurysm clipping surgery is performed safely and certainly. Furthermore, we believe that standardizing these versatile surgical procedures is helpful in developing the neurosurgical skills of young surgeons.

In aneurysm clipping, the clip blade is used to drop the dimensions of the aneurysm from a 3-dimensional structure to a 2-dimensional line or curve. Defining the “closure line” as that created by the clip blade, we have promoted the feasibility of achieving ideal clipping without leaving a vulnerable portion by setting this closure line while envisioning the vascular state prior to aneurysm development. This concept is the easiest to apply and the most practical in middle cerebral artery aneurysms due to vascular mobility. Here we discuss the approach of four patterns in which this concept is difficult to apply: 1) when clip insertion along the closure line is challenging; 2) when multiple closure lines are present; 3) when the optimal closure line is ambiguous; or 4) when arteriosclerosis is evident around the neck. This report will help improve the safety and robustness of treating middle cerebral artery aneurysms in which craniotomy plays a significant role.

Background and Purpose: A safe surgery for treating intracerebral hemorrhage (ICH) that reduces the risk of perioperative complications is warranted. Although endoscopic hematoma evacuation is an established treatment for ICH, the surgical indication regarding its application remains controversial. Recently, the use of cone-beam computed tomography (CBCT) with endoscopic hematoma evacuation has been reported, especially for evaluating residual hematomas. This report describes our experience of performing endoscopic hematoma evacuation with CBCT to treat ICH.

Methods: CBCT was used immediately before and during the surgery. We found a residual hematoma and closed the wound. If hematoma remained, we continued the procedure. After the surgery, the CBCT and regular CT images were compared.

Results: Seven patients underwent endoscopic hematoma evacuation with CBCT in the operating room over the past 2 years. In one of those 7 cases, a hematoma was evacuated before closing the wound and no residual hematomas were identified in the postoperative CT for any of the cases.

Conclusion: CBCT is an effective treatment for endoscopic hematoma evacuation, which does not leave any residual hematomas. Endoscopic hematoma evacuation with CBCT was found to be a safe procedure in our study.

Few studies have reported superficial temporal artery (STA)-middle cerebral artery (MCA) bypass for management of the acute stage of progressive stroke, and surgical indications remain unclear. We previously reported that STA-MCA bypass performed by experienced and skilled neurosurgeons was associated with favorable outcomes in carefully selected patients. Currently, we use the following patient-selection criteria for this surgery: atherothrombotic cerebral infarction, cerebral ischemia with brain blood flow ＜ 70% of that on the unaffected side, progressive symptoms despite optimal medical treatment or (previously “and”) spread of subcortical cerebral infarction, and interval of ＜ 72 hours from symptom onset. We describe treatment outcomes based on these criteria.

We compared 31 and 59 patients who underwent STA-MCA bypass during the acute stage of stroke between 2014 and 2018 and between 2002 and 2013, respectively at our hospital. The rate at which independent walking ability was achieved improved from 59.3% to 77.4%. However, the National Institutes of Health Stroke Scale scores did not significantly differ at the time of discharge. Acute-stage bypass procedures are increasingly being performed in clinical practice, and further accumulation of evidence is expected. In our view, larger numbers of patients are receiving treatment owing to expansion of indications for this operation based on closely examined policies.

Surgical resection is indicated when patients with brainstem cavernous hemangioma present with repeated hemorrhage and exacerbation of neurological symptoms. Achieving maximum excision of the lesions through a small incision on the brainstem and functional preservation are required in such cases.

Since 2011, the authors have experienced surgical resection of 13 brainstem cavernous hemangiomas. The trans-fourth ventricular approach was applied for 7 cases (6 females, mean age 53.8 years), including 5 pontine and 2 medullar lesions. The surgical approach was determined by the “2-point method”. This method connects the lesion's center and the point where the lesion was closest to the surface. The nerve function was protected during the operations with the aid of neuromonitoring. In addition, an angled neuroendoscope was used in 4 cases in the latter period to secure a different visual axis from that of the microscope. The lesions were completely removed except in 1 case.

The trans-fourth ventricular approach is an established surgical corridor for the cavernous hemangioma located in the dorsal pons and the medulla. Since surgeons need to remove the lesion through a small opening of the brainstem, neuromonitoring and adjunctive use of the endoscope were helpful. Selecting an appropriate surgical approach for the brainstem lesion is essential to achieve a safe and maximum degree of brainstem cavernous angiomas resections.

One year has passed since the stroke care unit (SCU) was established in our hospital. The number of acute revascularization treatments is gradually increasing. A total of 48 mechanical thrombectomy procedures were performed in 2018, more than usual. The revascularization rate of Thrombolysis in Cerebral Infarction (TICI) grade 2B or higher cases was 83% and the mean onset recanalization time (ORT) was 180 min. Three months later, the modified Rankin Scale (mRS) score 0-2 rate was 30%. The revascularization rate was equivalent to that of a reported randomized controlled trial (RCT), while the 3-month mRS rate was inadequate. Future treatments require examination, including system enhancement.

Intraosseous venous structures have been reported to be the origin of anterior condylar confluence (ACC) dural arteriovenous fistula (DAVF). Current treatment approaches may lead to hypoglossal nerve palsy complications. Here, we describe a case of ACC DAVF treated with selective occlusion of the intraosseous shunting pouch and venous outlet with the aim to prevent hypoglossal nerve palsy. A 77-year-old woman was admitted to our hospital with pulsatile tinnitus. Diagnostic angiography revealed a right ACC DAVF with anterograde venous drainage into the lateral and posterior condylar veins (LCV and PCV, respectively), vertebral venous plexus (VVP), and retrograde venous drainage into the inferior petrosal sinus (IPS). Coil embolization of the intraosseous shunting pouches, upstream of the ACC, did not lead to complete occlusion. Therefore, coil embolization of the venous drainage, such as the LCV and IPS, was performed. By these means, the patient was successfully treated with no further hypoglossal nerve palsy complication. Consequently, we can conclude that intraosseous shunting pouch coiling and outlet occlusion can be useful treatment alternatives in certain situations for the management of ACC DAVF, as they may avoid hypoglossal nerve palsy.

Objective: Symptoms of dural arteriovenous fistulas (dAVFs) typically depend on the site of the lesion. We report a rare case of superior sagittal sinus (SSS) dAVF in a patient with symptoms similar to those of a cavernous sinus (CS) dAVF.

Case presentation: A 60-year-old man presented with left-sided ophthalmoplegia and proptosis. Evaluation revealed SSS dAVF (Borden Type II), and isolated SSS. We observed cortical venous reflux (CVR) into the left CS and superior ophthalmic vein and performed endovascular recanalization of the SSS and transvenous embolization of all CVR. The dAVF gradually improved to Borden Type I. The patient’s symptoms improved after 3 months, with obliteration of the dAVF after 6 months.

Conclusion: This report describes a rare case of SSS dAVF accompanied by ocular symptoms.