Collateral Flow and White Matter Disease in Patients with Internal Carotid Artery Occlusion.

BACKGROUND: When an internal carotid artery (ICA) occludes, a patient may develop cerebral infarction (CI). We investigated whether CI caused by ICA occlusion (ICAO) is associated with collateral flow through the anterior and posterior communicating arteries (ACoA and PCoA). METHODS: In 100 patients with ICAO, we investigated CI and white matter disease by performing an MRI and the anatomy of the ACoA and PCoA were investigated by performing magnetic resonance angiography. All patients were divided into the symptomatic CI group or the no-CI group. The collateral flow pathway was estimated by the anterior cerebral artery (ACA)-PCoA score and the collateral flow volume after ICAO was estimated by the middle cerebral artery (MCA) flow score, based on how well the MCA was visualized. RESULTS: Of 100 patients with ICAO, the symptomatic CI group included 36 patients. ACA-PCoA score and white matter disease grades were significantly higher in the CI group (indicating poor collateral flow). More than 80% of patients with an ACA-PCoA score of 4 (poor collateral) experienced symptomatic CI. Thirty-one symptomatic CI patients (86%) had an MCA flow score of 1 or 2 (decreased MCA flow). CONCLUSION: The ACA-PCoA score and white matter disease grade may suggest an increased risk of CI following ICAO.

Leukocyte plugging and cortical capillary flow after subarachnoid hemorrhage.

BACKGROUND: It is believed that increased intracranial pressure immediately after subarachnoid hemorrhage (SAH) causes extensive brain ischemia and results in worsening clinical status. Arterial flow to the cerebral surfaces is clinically well maintained during clipping surgery regardless of the severity of the World Federation of Neurological Societies grade after SAH. To explore what kinds of changes occur in the cortical microcirculation, not at the cerebral surface, we examined cortical microcirculation after SAH using two-photon laser scanning microscopy (TPLSM). METHODS: SAH was induced in mice with an endovascular perforation model. Following continuous injection of rhodamine 6G, velocities of labeled platelets and leukocytes and unlabeled red blood cells (RBCs) were measured in the cortical capillaries 60 min after SAH with a line-scan method using TPLSM, and the data were compared to a sham group and P-selectin monoclonal antibody-treated group. RESULTS: Velocities of leukocytes, platelets, and RBCs in capillaries decreased significantly 60 min after SAH. Rolling and adherent leukocytes suddenly prevented other blood cells from flowing in the capillaries. Flowing blood cells also decreased significantly in each capillary after SAH. This no-reflow phenomenon induced by plugging leukocytes was often observed in the SAH group but not in the sham group. The decreased velocities of blood cells were reversed by pretreatment with the monoclonal antibody of P-selection, an adhesion molecule expressed on the surfaces of both endothelial cells and platelets. CONCLUSIONS: SAH caused sudden worsening of cortical microcirculation at the onset. Leukocyte plugging in capillaries is one of the reasons why cortical microcirculation is aggravated after SAH.

Early diagnosis of cerebral ischemia in cerebral vasospasm by oxygen-pulse near-infrared optical topography.

PURPOSE: Early diagnosis of vasospasm is a key factor in the choice of treatment after subarachnoid hemorrhage (SAH). However, a noninvasive method of diagnosing delayed ischemic neurological deficit (DIND) has not been established. We therefore propose a new method of diagnosing cerebral ischemia using near-infrared optical topography (OT) with oxygen inhalation. MATERIALS AND METHODS: We used a 44-channel OT system that covers the bilateral front otemporoparietal areas to assess 29 patients who underwent surgery within 72 h of the onset of SAH. The patients inhaled room air followed by oxygen for 2 min, and then peripheral oxygen saturation (SpO2) was continuously monitored at the index fingertip. The patients were assessed by N-isopropyl-p-[¹²³I]iodoamphetamine (IMP)-SPECT and OT on the same day. Ischemic findings were confirmed using principal component analysis with reference to the systemic SpO2value. RESULTS: Seven of 29 patients developed DIND. Evidence of ischemia was identified by OT in all seven of these patients before the onset of DIND. The OT and SPECT findings agreed in 27 (93 %) of the 29 patients. DISCUSSION AND CONCLUSIONS: Our method might detect cerebral ischemia before the onset of DIND and thus be clinically useful for assessing cerebral ischemia with vasospasm.

Prospective analysis of risk for bleeding after endoscopic biopsy without cessation of antithrombotics in Japan.

BACKGROUND AND AIM: In Japan, after the revision of the gastrointestinal endoscopic guidelines for patients taking antithrombotics, endoscopic biopsies were permitted while continuing antithrombotic treatment. However, the risk of bleeding after the biopsy with or without cessation of antithrombotics has not been fully evaluated because bleeding events are very rare. The aim of this prospective study was to evaluate the risk for bleeding after upper gastrointestinal biopsy without cessation of antithrombotics. METHODS: Consecutive patients who underwent upper gastrointestinal endoscopic biopsy from December 2011 to March 2014 were enrolled in this study. Antithrombotic medication and its cessation status was checked at enrollment. To confirm bleeding events associated with biopsy, medical examination at the hospital or direct confirmation by telephone was done within 1 month after the biopsy. RESULTS: Among the 3758 patients who underwent endoscopic biopsies, 394 patients (10.5%) were medicated with antithrombotics, and 286 of them (72.6% of the total antithrombotics users) did not undergo cessation. Bleeding after the biopsy occurred in six cases (0.15%, 95% CI; 0.09%∼0.22%), but there was only one case that had continued taking antithrombotics. The incidence of bleeding after biopsy was not significantly higher in the patients who had continued taking antithrombotics compared with the others (0.35% vs 0.14%, P = 0.38). CONCLUSION: This prospective study showed that continuation of antithrombotics did not increase the bleeding risk after upper gastrointestinal endoscopic biopsy.

The Early Postoperative Course of Cognitive Function and Preoperative Cerebrovascular Reserve.

BACKGROUND: Patients with severe steno-occlusive disease of a main cerebral artery without causative lesions on magnetic resonance imaging (MRI) often develop cognitive impairment. However, the effects of revascularization surgery and the source of the cognitive impairment remain unclear. Therefore, we investigated the early postoperative course of cognitive function and its association with cerebral blood flow (CBF), cerebrovascular reserve (CVR), white matter disease (WMD), lacunar infarction, and cerebrovascular risk factors. METHODS: Cognitive function was examined using neurobehavioral cognitive status examination (COGNISTAT) in 52 patients with steno-occlusive disease of a main cerebral artery before and at 6 months after superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis. We examined how cognition changed before and at 1, 3, and 6 months after STA-MCA anastomosis in 27 of 52 patients. CVR and CBF were calculated from 123I-N-isopropyl-p-iodoamphetamine single photon emission computed tomography, in addition to other cerebrovascular risk factors in 34 of 52 patients. Cerebral infarction and WMD (periventricular hyperintensity [PVH] and deep subcortical white matter hyperintensity) were also evaluated preoperatively by MRI. RESULTS: COGNISTAT scores improved at 1 month after STA-MCA anastomosis in patients with severe steno-occlusive disease of a main cerebral artery. Multiple stepwise regression analysis revealed that CVR (regression coefficient = -2.237, p = 0.0020) and PVH (regression coefficient = 2.364, p = 0.0029) were the best predictors of postoperative improvement in COGNISTAT scores (R 2 = 0.415; p = 0.0017). CONCLUSION: Cognitive function improves in relation to preoperative CVR and PVH early after STA-MCA anastomosis in patients with steno-occlusive disease of a main cerebral artery.

Ultrasonography monitoring with Superb Microvascular Imaging during cerebrovascular surgery.

INTRODUCTION: Ultrasonography (US) is used as a real-time dynamic imaging modality during neurosurgery. A novel Doppler US technique, Superb Microvascular Imaging (SMI), can be used to visualize low-velocity flow of small vessels at high resolution with high frame rates. We visualized vessel flow using this US SMI technique and contrast agent during cerebrovascular surgery. METHODS: Forty-three patients with an unruptured cerebral aneurysm (control), ischemic and hemorrhagic moyamoya disease, carotid artery stenosis, hemangioblastoma, severe stenosis of the middle cerebral artery, venous angioma, and intracerebral hemorrhage (ICH) underwent neurosurgery with US SMI monitoring using a contrast agent. The diameter, length, and number of penetrating vessels were analyzed in patients with an unruptured cerebral aneurysm (control), moyamoya disease, and ICH. RESULTS: Diameter and length of cerebral penetrating vessels were significantly increased in patients with moyamoya disease and ICH compared to control patients. The number of penetrating vessels was increased in moyamoya disease patients compared to control and ICH patients. In hemorrhagic moyamoya disease, flow in the penetrating vessels originated from a deep periventricular point and extended to the cerebral surface. Pulsatile cerebral aneurysms during clipping surgery and carotid artery stenosis during carotid endarterectomy were easily identified by SMI. Drastically increased vessel flow in patients with a hemangioblastoma or a venous angioma was observed. CONCLUSION: Using the US SMI technique and contrast agent, we obtained useful flow information of the vascular disease structure and intracerebral deep small vessels during cerebrovascular surgery. Further quantitative analysis will be informative and helpful for cerebrovascular surgery.

The role of nitric oxide in the induction of caudal-type homeobox 2 through epidermal growth factor receptor in the development of Barrett's esophagus.

OBJECTIVE: The high concentration of nitric oxide (NO) around the gastro-esophageal junction (GEJ) might play an important role in the development of Barrett's esophagus (BE), a precursor of Barrett's adenocarcimona. Although previous studies revealed that the expression of caudal-type homeobox 2 (CDX2), an important marker of BE, might be induced through Epidermal Growth Factor Receptor (EGFR), the roles of NO in this signal transduction remain unclear. MATERIAL AND METHODS: First, we investigated the expressions of EGFR, CDX2 and nitrotyrosine by immunohistochemical study for BE and squamous epithelium of human specimens. Second, we studied the effect of peroxynitrite, peroxynitrite stimulator, SIN-1, or NO donor, NOC7, on the expression of phosphorylated EGFR and CDX2 in KYSE30, an EGFR-rich human esophageal squamous cell carcinoma cell-line. Specific inhibitors for EGFR, AG1478 and small interfering RNA for EGFR (EGFR-siRNA) were employed to elucidate the role of EGFR in the induction of CDX2. RESULTS: The immunohistochemical study revealed that the expressions of EGFR, CDX2 and nitrotyrosine in BE were stronger than those in squamous epithelium with positive correlations. Exposure to peroxynitrite, SIN-1 or NOC7 induced EGFR phosphorylation and CDX2 expression in dose- and time-dependent manners. Both EGFR phosphorylation and CDX2 induction were significantly diminished by AG 1478 and EGFR-siRNA. CONCLUSIONS: We revealed for the first time that extrinsic NO might directly induce CDX2 expression through EGFR phosphorylation. We suggested that NO had an important role in the development of BE from squamous epithelium around GEJ.

Arytenoid adduction combined with medialization laryngoplasty under general anesthesia using a laryngeal mask airway.

PURPOSE: Laryngeal framework surgery is usually performed under local anesthesia but cannot be tolerated by some patients. To develop a new procedure for these patients, we evaluated voice outcomes after arytenoid adduction combined with medialization laryngoplasty under general anesthesia using a laryngeal mask airway (LMA) for unilateral vocal cord paralysis. MATERIALS AND METHODS: Eleven consecutive patients with severe unilateral vocal cord paralysis, with a maximum phonation time of less than 5 seconds, underwent arytenoid adduction combined with medialization laryngoplasty under general anesthesia using an LMA. Each paralyzed vocal cord was observed by intraoperative videolaryngoscopy. The vocal cord was moved to the position where the best vocal outcome could be expected, according to 3 parameters obtained from glottal images. RESULTS: All patients achieved a maximum phonation time of more than 11 seconds. The mean airflow rate, which ranged from 550 to 1000 mL/s before surgery, improved to less than 390 mL/s. Perceptual evaluation using the grade, roughness, breathiness, asthenia and strain scale also improved significantly. CONCLUSIONS: These results were equivalent to those of previous reports of surgeries performed under local anesthesia. Intraoperative endoscopic vocal cord observation through the LMA may have contributed to the positive results.

Direct measurement of gastroesophageal reflux episodes in patients with squamous cell carcinoma by 24-h pH-impedance monitoring.

OBJECTIVES: Recent studies have consistently reported a significant association between gastric atrophy and esophageal squamous cell carcinomas (ESCCs). However, causative factors responsible for the linkage remain to be clarified. Multichannel intraluminal impedance monitoring in conjunction with a pH sensor (MII-pH) is a reliable technique to evaluate gastroesophageal reflux (GER) episodes, independent of the acidity. We investigated the potential roles of GER in the pathogenesis of ESCC with MII-pH. METHODS: From August 2008 to May 2010, 14 consecutive inpatients with superficial ESCCs (ESCC group) and 14 age- and sex-matched inpatients without any esophageal dysplastic lesions (non-ESCC group) were enrolled. Twenty-four hour portable MII-pH monitoring was performed under standard hospitalized conditions. The data of MII-pH were used to identify acid reflux (AR: pH drop below 4.0 during a reflux episode) and non-AR (NAR: pH drop above 4.0 during a reflux episode). RESULTS: The median intragastric pH of the ESCC group was 4.7 (2.3-6.4), implying hypochlorhydria in this patient group. The numbers of total reflux and NAR episodes in the ESCC group were significantly higher than those in the non-ESCC group (56 (43-87) vs. 35.5 (18-47), P=0.016 for total reflux and 46.5 (32-84) vs. 24.5 (8-37), P=0.012 for NAR), whereas the numbers of AR were similar in both groups. In addition, there was significance in the category of percentage time of bolus reflux episodes. CONCLUSIONS: Using MII-pH monitoring, we revealed the clinical significance of GER, especially NAR, in ESCCs. NAR may be a key factor in the link between gastric atrophy and ESCCs.

The balance between 4-hydroxynonenal and intrinsic glutathione/glutathione S-transferase A4 system may be critical for the epidermal growth factor receptor phosphorylation of human esophageal squamous cell carcinomas.

Oxidative stress might participate in the carcinogenesis of human esophageal squamous cell carcinomas (hESCC). 4-Hydroxynonenal (HNE) is a major product of membrane lipid peroxidation with short life. It might act as an important mediator through the generation of adducts and activate epidermal growth factor receptor (EGFR) signaling. It is mainly trapped with glutathione (GSH) and catalyzed by glutathione S-transferases (GSTs). This study aimed to elucidate the possible participation of HNE, GSH/GST system, and EGFR signaling in hESCC development. Immunohistochemistry of HNE adducts, EGFR, and phosphorylated EGFR (pEGFR) was performed with hESCC specimens. The effect of HNE on the phosphorylation of EGFR and its downstream PhospholipaseCγ1 (PLCγ1) was investigated with KYSE30 cell-line. Pretreatment with GSH inducer N-acetylcysteine (NAC) or GSH inhibitor Buthionine sulfoximine (BSO) and mandatory transfection of hGSTA4 gene in KYSE30 were conducted to investigate the relationship between HNE and GSH/GST system. Immunoreactants of HNE adducts, EGFR, and pEGFR were increased in hESCC compared to non-cancerous epithelium with positive correlations. The treatment of HNE ligand-independently induced the phosphorylation of EGFR and PLCγ1 accompanying the diminishment of intracellular GSH level. NAC increased GSH contents but BSO decreased in dose-dependent manners. Reflecting changes in GSH, HNE-induced EGFR phosphorylation was suppressed by NAC, whereas it was promoted by BSO. Mandatory expression of hGSTA4 suppressed HNE-induced events. We first demonstrated that the ligand-independent activation of EGFR by the balance between the stimulation of HNE and the prevention of intrinsic GSH/GST system might participate in the development of hESCC.

Clinical case of lung spindle cell carcinoma markedly responsive to pembrolizumab.

A 52-year-old man underwent pneumonectomy of the left lung for previously diagnosed primary spindle cell carcinoma (pT4aN1M0, stage III B) with programmed death-ligand 1 expression (tumor proportion score ≥95%) and without epidermal growth factor receptor gene mutation and anaplastic lymphoma kinase fusion gene. However, brain metastasis and chest wall tumor relapse occurred. Considering insufficient improvement with gamma knife treatment for brain metastasis and combination chemotherapy (paclitaxel, carboplatin, and bevacizumab), pembrolizumab monotherapy and palliative irradiation therapy for chest metastases were started after brain tumor volume reduction using craniotomy. Brain edema and chest wall metastases markedly improved following a pseudoprogression of the brain edema accompanied by a performance status decline; this effect continued until 11 cycles of pembrolizumab administration.

Clinical Features of Esophageal Eosinophilia According to Endoscopic Phenotypes.

Objective Esophageal eosinophilia (EE), a histological hallmark of eosinophilic esophagitis, is classified into two endoscopic phenotypes: localized and diffuse EE. Our aim was to determine the prevalence of EE localized in the lower esophagus and to describe its clinical features in comparison with diffuse EE. Methods Data from 81 consecutive patients with EE were retrospectively investigated. EE was histologically defined as ≥15 eosinophils per high-power field. Based on the endoscopic appearance with a histological assessment, EE was classified as either diffuse or localized type. We compared the clinical features, including the medical treatment and natural course, between the two types. Results Of the 81 patients, 52 (64.2%) had diffuse EE, and 29 (35.8%) had localized EE. Among men patients, localized EE was significantly more common than diffuse EE. In localized EE, dysphagia and food impaction were less prevalent, and the presence of rings was significantly less common than in diffuse EE. Acid-suppressive therapy was administered to only 3 of the 29 patients with localized EE. In asymptomatic patients, especially those with localized EE, endoscopic abnormalities did not worsen but rather improved in some findings, such as with regard to furrows or exudate, during the natural course of three years without medical treatment. Conclusion Localized EE has a strong predilection for men patients and accounted for more than one third of all cases of EE. This condition appears to be less symptomatic and necessitates milder medical treatment than diffuse EE and might not worsen progressively.

Promoter methylation of galanin receptors as epigenetic biomarkers for head and neck squamous cell carcinomas.

INTRODUCTION: While remarkable progress has been made in standard treatments for head and neck squamous cell carcinomas (HNSCCs), the long-term survival remains at an unsatisfactory 40-50%. To improve the survival rate, biomarkers for optimal treatment selection and prognostic prediction, as well as novel, low-toxicity treatment strategies, are required. Galanin receptor (GALR) 1 and GALR2 are well-studied tumor suppressors in HNSCCs. Compared with other clinicopathological factors, the epigenetic variants of GALRs have been found to be the most powerful markers to predict the prognosis of HNSCC patients. Areas covered: This review outlines the functions and signaling pathways of GALRs and explains the potential of GALR promoter methylation as a biomarker for HNSCC prognosis. We also summarize recent developments in promoter methylation studies in HNSCC and indicate future directions for GALR promoter methylation studies. Expert commentary: GALR studies have highlighted two major aspects with implications in HNSCC - that G-protein coupled receptors (GPCRs) act as tumor suppressor genes and that GALR promoter methylation is significantly related to the carcinogenesis of HNSCC. The findings of GALR studies can be applied to studies on other GPCRs and further in-depth DNA methylation studies. Deeper insights into GPCR epigenetics are expected to markedly improve HNSCC treatment.

[Evoked potential monitoring in an operation of neurosurgery].

In the neurosurgical field, the evoked potential is employed for the monitoring of intraoperative nerve function. During evoked potential monitoring, surgical manipulation-related nerve dysfunction is detected, and functional localization/nerves in the cerebral cortex are identified to prevent postoperative neurological complications. It is important to reduce the contact resistance to 2 kOmega or less on the application of plate electrodes used for recording and prevent noise by bundling electrode leads, to ensure a stable evoked potential during surgery. In our laboratory, intraoperative monitoring, such as ABR to prevent auditory disturbance, SEP to detect cerebral ischemia, cortical SEP and MEP to prevent motor paralysis, and evoked electromyography to identify/maintain the cranial nerves including the facial, trigeminal, oculomotor, and abducens nerves, is performed based on requests from the Department of Neurosurgery.

Superficial Temporal Artery-middle Cerebral Artery Anastomosis for Ischemic Stroke due to Dissection of the Intracranial Internal Carotid Artery with Middle Cerebral Artery Extension.

A 31-year-old man presented with a sudden-onset headache, right hemiparesis, and dysarthria on day 0 and was diagnosed with acute ischemic stroke due to dissection of the left intracranial internal carotid artery with middle cerebral artery extension. His symptoms progressed despite the institution of treatment, suggesting progression of the dissection. On day 5 after symptom onset, the patient underwent superficial temporal artery-middle cerebral artery anastomosis. No new ischemic stroke event occurred after surgery. Cerebral angiography performed 6 months after surgery showed spontaneous resolution of the dissection. The patient recovered to a modified Rankin Scale score of 2 and was able to return to work. The results of the present case suggest that superficial temporal artery-middle cerebral artery anastomosis is an effective treatment for ischemic stroke due to dissection of the intracranial internal carotid artery with middle cerebral artery extension.

Epigenetic inactivation of galanin receptors in salivary duct carcinoma of the parotid gland: Potential utility as biomarkers for prognosis.

Salivary duct carcinoma (SDC) constitutes one of the most aggressive cancers in the salivary gland and is associated with a poor prognosis; however, no established systemic therapy options are available. SDC exhibits biological similarity to prostate and breast cancers, therefore anti-hormone therapy and molecular target therapies are available, however with limited beneficial effects. Galanin and galanin receptors (GALRs) are well established as molecular biomarkers to predict the survival rate and risk of recurrence of head and neck squamous cell carcinoma. The present study investigated the clinicopathological features of patients with SDC and the methylation status of their galanin and GALR genes to demonstrate the prognostic value for this disease. The median overall survival (OS) was 37.2 months. T-stage, N-stage, disease stage, tumor size, and preoperative facial paralysis were significantly associated with OS, whereas human epidermal growth factor receptor 2 (HER2) overexpression was not. GALR1 and GALR2 methylation rates in tumor tissues were significantly increased compared with normal tissues with 9.85- and 4.49-fold increase, respectively. p27kip1 and p57kip2 expression significantly inversely correlated with the methylation rate of GALR1 and GALR2. In addition, the observed GALR1 and/or GALR2 methylation rates were significantly correlated with a decrease in OS. These results suggest that GALR1 and GALR2 may serve as potential prognostic factors and therapeutic targets in SDC.

Cochlear Nerve Action Potential Monitoring for Preserving Function of an Unseen Cochlear Nerve in Vestibular Schwannoma Surgery.

BACKGROUND: Intraoperative monitoring of cochlear nerve action potential (CNAP) has been used in patients with small vestibular schwannoma (<15 mm) to preserve cochlear nerve function. We performed surgery for a larger vestibular schwannoma under CNAP monitoring with the aim of preserving cochlear nerve function, and compared the data with findings from 10 patients with hemifacial spasm who underwent microvascular decompression surgery. CASE DESCRIPTION: We report the case of a patient with a 26-mm vestibular schwannoma and normal hearing function who underwent neurosurgery under electrophysiological monitoring of the facial and cochlear nerves. Amplitudes of evoked facial muscle responses were maintained at approximately 70% during the operation. The latency of wave V on brainstem auditory evoked potential (BAEP) increased by 0.5 ms, and amplitude was maintained at approximately 70% of the value at the beginning of the operation. Latencies of P1, N1, and P2 on CNAP did not change intraoperatively. These latencies were comparable to those of 10 normal patients with hemifacial spasm. CNAP monitoring proved very useful in confirming the location of the cochlear nerve in the operative field and preserving cochlear nerve function. Both facial nerve function and hearing acuity were completely preserved after tumor removal, and wave V latency on BAEP returned to normal and was maintained in the normal range for at least 2 years. CONCLUSIONS: CNAP monitoring is extremely useful for preserving the function of the unseen cochlear nerve during vestibular schwannoma surgery.

Design of a Locator for Designing the Shortest Incision for a Polygonal Dural Window.

When a wide polygonal dural window is created, a short dural incision length is preferred by surgeons because suturing a wastefully long incision line during closure is troublesome. A locator to facilitate making the shortest dural incision when creating a polygonal dural window would be helpful. We geometrically analyzed the shortest incision design for a pentagonal dural window and produced a simple locator for intraoperatively implementing this design. The design for a pentagonal dural window with the shortest incision is the same as the design for a minimum Steiner tree (MST) problem with five vertices. The MST consists of three interconnected Steiner points (SPs) with three equal, radiating branches. We produced a template of the features of the MST for a polygon (MST template) as a locator. The MST template consists of several uniform Steiner units (SUs), each of which has an SP at the center and three wings that branch off of the SP, and each SU also has three slits through which the wings of another unit can pass. This mechanism allows us to freely adjust the distance between the SPs of separate SUs. In clinical practice, we can create the shortest incision design for a quadrilateral or pentagon by arranging MST templates combining two or three SUs. If we open a wide dural window, the total incision lengths created using our method are 1-5 cm shorter than conventional incisions. The MST template accurately and easily reveals the shortest incision design.

Clinical significance of the coexistence of carotid artery plaque and white matter disease in patients with symptomatic cerebral infarction.

OBJECTIVES: Symptomatic cerebral infarction (CI) can occur in patients without main cerebral artery stenosis or occlusion. This study investigated the unique features of carotid artery plaque and white matter disease (WMD) in patients with symptomatic CI and transient ischemic attack (TIA) but without stenosis or occlusion of a main cerebral artery. PATIENTS AND METHODS: We studied 647 patients who underwent both carotid ultrasound examination and brain magnetic resonance images. Plaque score (PS), plaque number, maximal plaque intima-media thickness and grades of WMD were examined. Subjects were divided into four groups, the CI group, TIA group, myocardial infarction (MI) group and risk factor (RF) group. Plaque and WMD were analyzed in cerebral ischemia group (CI and TIA), compared to non-cerebral ischemia groups and to a high PS group and a high WMD grade group from the RF group. RESULTS: Both of each value of plaque and grades of WMD in the cerebral ischemia group were significantly higher than those in other groups. Grades of WMD in the cerebral ischemia group were significantly higher than those in the high PS group, although there was no significant difference of the each value of plaque between the two groups. The each value of plaque in the cerebral ischemia group was also significantly higher than those in the high WMD grade group, although there was no significant difference of grade of WMD between the two groups. CONCLUSION: Simultaneous increases in carotid artery plaque and WMD are associated with symptomatic CI, which is not caused by stenosis or occlusion of a main cerebral artery.

Improvement of neurovascular function and cognitive impairment after STA-MCA anastomosis.

OBJECTIVE: In patients with severe steno-occlusive disease of a main cerebral artery, decreased cerebrovascular reserve (CVR) and cognitive impairment without causative focal lesions on magnetic resonance imaging have been reported. We examined ipsilateral and contralateral CVR and cognition before and after superficial temporal artery-middle cerebral artery (MCA) anastomosis operation in patients with internal carotid artery (ICA) or MCA occlusion. METHODS: In 30 patients with ICA or MCA occlusion, cognitive impairment, and decreased CVR, we examined cognition, CVR, leukoaraiosis grades, and blood data. Data from 15 patients who underwent anastomosis were compared to that in 15 patients who did not undergo anastomosis, and to bilateral data already reported on 65 patients with severe steno-occlusive disease. RESULTS: Cerebral blood flow, CVR, and cognition improved after anastomosis compared to before, and compared to patients without anastomosis; improved values were maintained for 5years. CVR recovered after anastomosis, matching the linear relationship between ipsilateral and contralateral CVR seen in the 65 patients. CONCLUSION: The postoperative improvement in cognition and synchronized recovery on the regression line between CVR of the ipsilateral occlusion and contralateral sides may suggest that the CVR is widespread and nonselectively related to cognitive function.