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We study the dynamics of void formation through the shape evolution of high-aspect-ratio cylindrical holes in Si(001) substrates under hydrogen annealing. We compare the observed evolution of these holes with numerical simulations based on the continuum theory for surface-diffusion-driven shape evolution. We find that a strong morphological instability arises near the hole opening, regardless of the presence of anisotropy in surface energy. The observed shape evolution of high-aspect-ratio holes during hydrogen annealing is understood as a surface-diffusion-driven evolution subject to the stability of the facets which form the vertical sidewall. [ABSTRACT FROM AUTHOR]

We have studied the structural evolution of voids in the Si substrate and the formation of silicon-on-nothing (SON) structures upon spontaneous reshaping of square arrays of cylindrical holes on Si(001) substrates by hydrogen annealing. Vertically elongated voids covered with {111}, {100}, {110}, and {113} facets are initially formed by the closure of the hole inlets. This step is followed by volume preserving shape changes of the faceted voids in the bulk Si. In situations where the hole-hole separation is sufficiently small, void coalescence occurs due to the shape changes of individual voids, leading to the formation of a SON structure. Until void coalescence, the shapes of individual voids change without being affected by the adjacent voids. Numerical simulations of the shape change of a completely faceted void via solely surface diffusion have been performed and have reproduced the observed shape change. [ABSTRACT FROM AUTHOR]

Although rare, penetrating cervical vascular injury poses significant challenges with a poor patient prognosis, often attributed to severe hemorrhage and accompanying injuries. We encountered a case of hemorrhagic shock resulting from a penetrating injury to the common carotid artery (CCA), which was successfully managed using a combination of endovascular therapy and direct surgical intervention. A 23-year-old man presented with a self-inflicted stab wound on the left side of his neck from a kitchen knife. This injury resulted in hemorrhagic shock and coma. Initial management included fluid resuscitation and transfusion, with continuous manual compression to control profuse bleeding. Contrast-enhanced neck and brain computed tomography (CT) showed a left CCA injury that was challenging to directly address due to its low anatomical location and continuous bleeding. Neurosurgeons initiated endovascular treatment by placing a guiding balloon catheter proximal to the left CCA for occlusion. Despite this, pulsatile bleeding persisted, prompting the distal placement of a balloon catheter to achieve better bleeding control. Cardiovascular surgeons then performed direct surgery, clearly identifying damage to the anterior and posterior walls of the CCA. The repair involved the use of a self-made cylindrical bovine pericardial patch, which resulted in successful revascularization. Following surgery, the patient regained independent mobility and was discharged. This case emphasizes the importance of a prompt and reliable approach involving endovascular intervention for initial bleeding control followed by precise repair through direct surgery, especially in challenging bleeding scenarios., Competing Interests: The authors declare no conflicts of interest., (© 2024 The Japan Neurosurgical Society.)

Introduction The degree to which each human brain hemisphere governs specific cognitive processes, such as language and handedness (the preference or dominance of one hand over the other), varies across individuals. Research has explored the nature of language laterality in left-handed (LH) individuals, indicating that left-hemisphere dominance for language is commonly observed across both left- and right-handed populations. Advanced imaging techniques, including functional transcranial Doppler sonography and fMRI, have revealed subtle differences in language lateralization between LH and right-handed (RH) individuals, particularly in semantic processing tasks. These findings underscore the complex relationship between handedness and language lateralization. This study investigates the spatial patterns of language lateralization in LH and RH individuals using high-resolution fMRI data and the Human Connectome Project (HCP) multimodal parcellation (MMP).  Method We utilized pre-processed MRI scans from the HCP database, comprising 140 healthy young adults, with 70 individuals in each of the RH and LH groups. The language task includes two contrasts: the STORY contrast, where participants listened to brief auditory stories compared to a baseline, and the STORY-MATH contrast, where participants listened to stories versus solving addition and subtraction problems. Data processing involved the HCP Pipelines and the MMP atlas was applied for analysis. The Edinburgh Handedness Inventory categorized participants as either LH or RH. For analysis, we focused on the number of brain surface elements (3D surface vertices) with positive elements (PEs) within each brain region, indicating blood-oxygen-level-dependent (BOLD) activity. The study's methodology aimed to quantify and compare PEs across the hemispheres (paired sample) and handedness groups (independent sample), providing insights into language lateralization. Statistical analysis involved Mann-Whitney U tests for differences across gender and handedness groups and robust t-tests for hemispheric dominance. Results were visualized by projecting mean and effect size values onto a 3D brain surface. Results The analysis of hemispheric mean differences in PEs revealed robust left hemisphere dominance in both the STORY and STORY-MATH contrasts among the RH group, while the LH group exhibited more balanced activity. Significant variations in PEs were observed across numerous MMP regions, with LH individuals showing pronounced asymmetry in 67 and 76 MMP regions (out of 180 regions) in the STORY and STORY-MATH contrasts, respectively, compared to 83 and 99 regions in RH individuals. Additionally, when comparing LH and RH groups, significant differences in PEs were identified within 14 MMP regions (out of 360 regions), all demonstrating significant asymmetry in LH individuals and primarily located in the right hemisphere (12 regions), notably in the inferior parietal lobule (Brodmann 39 and 40). No differences were found in the STORY-MATH contrast. Conclusion We identified hemispheric left-lateralization dominance in brain areas associated with language processing, irrespective of handedness. However, employing multimodal brain parcellation with fMRI language tasks unveiled notable differences in specific regions. Particularly striking was the heightened activity observed in certain right hemisphere regions among LH individuals., Competing Interests: Human subjects: Consent for treatment and open access publication was obtained or waived by all participants in this study. Animal subjects: All authors have confirmed that this study did not involve animal subjects or tissue. Conflicts of interest: In compliance with the ICMJE uniform disclosure form, all authors declare the following: Payment/services info: The editing and publication services were supported by Grant-in-Aid for Early-Career Scientists Number 24K19553, awarded to Dr. Mudathir Bakhit by the Japanese Ministry of Education, Culture, Sports, Science, and Technology. Financial relationships: All authors have declared that they have no financial relationships at present or within the previous three years with any organizations that might have an interest in the submitted work. Other relationships: All authors have declared that there are no other relationships or activities that could appear to have influenced the submitted work., (Copyright © 2024, Bakhit et al.)

Background: The EF-14 clinical trial demonstrated the safety and efficacy of tumor-treating fields (TTFields) for newly diagnosed glioblastoma. This study aimed to clarify the current status, safety, and efficacy of TTFields in Japanese patients who meet the EF-14 inclusion criteria., Methods: This was a multicenter retrospective cohort study. Background, treatment, and outcome data of patients who satisfied the inclusion criteria of the EF-14 trial were collected from 45 institutions across Japan. The rate, determinants, and current status of TTField use, including its safety and efficacy in terms of progression and survival, were retrospectively investigated. This study was conducted in accordance with the STROBE checklist., Results: Among the 607 patients enrolled, 70 were excluded due to progressive disease during radiation and temozolomide therapy, age > 80 years old, and Karnofsky Performance Status score of <70. Among the remaining 537 patients, 210 (39%) underwent TTField treatment. Multivariate analysis revealed younger age and spouse as a caregiver as significant factors for TTField use. The compliance rate of TTField use exceeded 75% in 60% of patients, with a median TTField usage duration of 11 months. Skin disorders requiring medical treatment occurred in 56% of patients. Multivariate Cox proportional hazards analysis in the whole series and propensity score-matched analysis revealed that TTField use was not a prognostic factor for progression-free survival (PFS) or overall survival (OS)., Conclusions: TTField use did not have a substantial effect on either PFS or OS in Japanese patients with glioblastoma, despite compliance rates comparable to those observed in the EF-14., Competing Interests: M.Ka. received honoraria from Novocure and Eisai and research funding from Eisai. K.S. received honoraria from Novocure and Eisai and research funding from Eisai and Nippon Kayaku. S.Y. received honoraria from Novocure. M.N. received honoraria from Novocure and Eisai. T.M. received honoraria from Novocure and Eisai. M.N. received honoraria from Novocure, Eisai, and Nippon Kayaku and research funding from Eisai and MSD. K.Y. received honoraria from Novocure. H.Y. received honoraria from Novocure and Eisai. Y.Nakahara received honoraria from Novocure and Eisai. Y.H. received honoraria from Novocure and Eisai and research funding from Eisai. M.Ki. received honoraria from Novocure and Eisai. A.Y. received research funding from Eisai. Y.K. received honoraria from Novocure and Eisai. M.T. received research funding for clinical trial from Eisai. Y.A. received honoraria from Novocure, Eisai, and Nippon Kayaku. Y.Narita received honoraria from Novocure and Eisai and research funding from Eisai. All remaining authors have declared no conflicts of interest., (© The Author(s) 2024. Published by Oxford University Press, the Society for Neuro-Oncology and the European Association of Neuro-Oncology.)

Discrepancies in the terminology describing sulcal structures within the lateral superior parietal lobule prompted our comprehensive investigation to clarify their morphology and nomenclature. We reviewed literature from the 19th century to the present, focusing on the intraparietal sulcus, interparietal sulcus, superior parietal sulcus, transverse parietal sulcus, paroccipital sulcus, and transverse occipital sulcus. Additionally, we analyzed neuroimaging data from 40 healthy young adults and two cadavers. Our investigation revealed that the original term intraparietal sulcus, introduced by Sir Turner, described a complex structure comprising the inferior segment of the postcentral sulcus, a horizontally extending component into the occipital lobe, and the transverse occipital sulcus. We also found that the superior parietal sulcus is often synonymous with transverse parietal sulcus, the sulcus of Brissaud is an eponym that shall describe the paroccipital sulcus's dorsal parietal ramus, and the transverse occipital sulcus is the combination of the occipital rami of the paroccipital sulcus. Additionally, we identified an unnamed transverse segment of the intraparietal sulcus, the intraparietal sulcus-transverse. Based on these observations, we consider that the sulci of the lateral superior parietal lobule primarily include the intraparietal sulcus, with longitudinal and transverse segments, the transverse parietal sulcus of Brissaud, and the paroccipital sulcus of Wilder., (© The Author(s) 2024. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Purpose: This study aimed to evaluate the effects of an artificial intelligence (AI) chatbot (ChatGPT-3.5, OpenAI) on preoperative anxiety reduction and patient satisfaction in adult patients undergoing surgery under general anesthesia., Design: The study used a single-blind, randomized controlled trial design., Methods: In this study, 100 adult patients were enrolled and divided into two groups: 50 in the control group, in which patients received standard preoperative information from anesthesia nurses, and 50 in the intervention group, in which patients interacted with ChatGPT. The primary outcome, preoperative anxiety reduction, was measured using the Japanese State-Trait Anxiety Inventory (STAI) self-report questionnaire. The secondary endpoints included participant satisfaction (Q1), comprehension of the treatment process (Q2), and the perception of the AI chatbot's responses as more relevant than those of the nurses (Q3)., Findings: Of the 85 participants who completed the study, the STAI scores in the control group remained stable, whereas those in the intervention group decreased. The mixed-effects model showed significant effects of time and group-time interaction on the STAI scores; however, no main group effect was observed. The secondary endpoints revealed mixed results; some patients found that the chatbot's responses were more relevant, whereas others were dissatisfied or experienced difficulties., Conclusions: The ChatGPT intervention significantly reduced preoperative anxiety compared with the control group; however, no overall difference in the STAI scores was observed. The mixed secondary endpoint results highlight the need for refining chatbot algorithms and knowledge bases to improve performance and satisfaction. AI chatbots should complement, rather than replace, human health care providers. Seamless integration and effective communication among AI chatbots, patients, and health care providers are essential for optimizing patient outcomes., Competing Interests: Declaration of Competing Interest None to report., (Copyright © 2024. Published by Elsevier Inc.)

To improve optic nerve function in a patient with progressive visual dysfunction, performing early decompressive and debulking surgery for a metastatic tumor located in the optic canal is essential. The endoscopic endonasal approach could be a practical and effective alternative for lesions in the inferomedial part of the optic canal. A 66-year-old man with a right visual eye field deficit had multiple lesions in the pineal gland, occipital lobe, and right inferomedial optic canal. The optic nerve was distorted by a tumor compressing against the falciform ligament. Although a systemic examination suggested the presence of primary lung cancer, the patient only complained of progressive visual impairment in the right eye. We planned surgery with endoscopic transethmoidal and transsphenoidal approaches to restore visual function and make a pathological diagnosis. During the procedure, we drilled the sella floor, tuberculum sellae, and optic canal and successfully removed the tumor underneath the dura mater. The patient's visual function improved rapidly following surgery, and no complications were observed, such as cerebrospinal fluid leakage. After confirming the pathological diagnosis, the patient subsequently received whole-brain radiotherapy. The endoscopic endonasal skull base approach to the optic canal region could be a practical alternative for treating symptomatic metastatic tumors., Competing Interests: The authors have no conflicts of interest. All authors have registered self-reported COI Disclosure Statement Forms online., (© 2024 The Japan Neurosurgical Society.)

Background: Bifocal germ cell tumors, with primarily identical tissue composition, occur concurrently in the neurohypophyseal and pineal regions., Observations: A 16-year-old male patient exhibited increased intracranial pressure symptoms, with concurrent tumors in the pineal and neurohypophyseal regions, causing obstructive hydrocephalus. His serum human chorionic gonadotropin level was elevated, measuring 506.6 mIU/mL. Upon gross endoscopic examination, the pineal tumor appeared white, whereas the neurohypophyseal tumor appeared red and hemorrhagic. Because of the limited sample size of the latter, a frozen section biopsy was feasible only for the pineal lesion, which indicated the presence of a germinoma. Subsequently, carboplatin and etoposide were administered, resulting in the reduction of the pineal tumor, but no effect was observed in the neurohypophyseal tumor. Histopathological analysis confirmed the pineal lesion as a germinoma, whereas the neurohypophyseal lesion was an embryonal carcinoma. Thus, the treatment was altered to ifosfamide, carboplatin, and etoposide (ICE), leading to a response in both tumors. The patient underwent three additional cycles of ICE therapy and high-dose chemotherapy, followed by whole craniospinal irradiation, achieving complete remission., Lessons: Although most bifocal germ cell tumors share the same histological tissue, occasional differences may arise, necessitating separate biopsies for accurate assessment.

Gliomas are the most prevalent primary tumor of the central nervous system. Despite advances in imaging technologies, neurosurgical techniques, and radiotherapy, a cure for high-grade glioma remains elusive. Several groups have reported that protein tyrosine phosphatase receptor type Z (PTPRZ) is highly expressed in glioblastoma, and that targeting PTPRZ attenuates tumor growth in mice. PTPRZ is modified with diverse glycan, including the PTPRZ-unique human natural killer-1 capped O-mannosyl core M2 glycans. However, the regulation and function of these unique glycans are unclear. Using CRISPR genome-editing technology, we first demonstrated that disruption of the PTPRZ gene in human glioma LN-229 cells resulted in profoundly reduced tumor growth in xenografted mice, confirming the potential of PTPRZ as a therapeutic target for glioma. Furthermore, multiple glycan analyses revealed that PTPRZ derived from glioma patients and from xenografted glioma expressed abundant levels of human natural killer-1-capped O-Man glycans via extrinsic signals. Finally, since deficiency of O-Man core M2 branching enzyme N-acetylglucosaminyltransferase IX (GnT-IX) was reported to reduce PTPRZ protein levels, we disrupted the GnT-IX gene in LN-229 cells and found a significant reduction of glioma growth both in vitro and in the xenograft model. These results suggest that the PTPR glycosylation enzyme GnT-IX may represent a promising therapeutic target for glioma., Competing Interests: Conflict of interest The authors declare that they have no conflicts of interest with the contents of this article., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

Neurofibromatosis type 2 (NF2), a multiple neoplasia syndrome, is a manifestation of an impaired expression of the merlin protein, exerting inhibitory effects on cell proliferation signals due to abnormalities of the NF2 gene located on chromosome 22. About half of patients inherit a germline mutation from a parent, and nearly 60% of de novo NF2 patients are estimated to have somatic mosaicism. The development of technical methods to detect NF2 gene mutation, including targeted deep sequencing from multiple tissues, improved the diagnostic rate of mosaic NF2. With improved understanding of genetics and pathogenesis, the diagnostic criteria for NF2 were updated to assist in identifying and diagnosing NF2 at an earlier stage. The understanding of cell signaling pathways interacting with merlin has led to the development of molecular-targeted therapies. Currently, several translational studies are searching for possible therapeutic agents targeting VEGF or VEGF receptors. Bevacizumab, an anti-VEGF monoclonal antibody, is widely used in many clinical trials aiming for hearing improvement or tumor volume control. Currently, a randomized, double-masked trial to assess bevacizumab is underway. In this randomized control trial, 12 other Japanese institutions joined the principal investigators in the clinical trial originating at Fukushima Medical University. In this review, we will be discussing the latest research developments regarding NF2 pathophysiology, including molecular biology, diagnosis, and novel therapeutics.

Double or multiple pituitary adenomas expressing different types of transcription factors and collision tumors of pituitary adenomas and craniopharyngiomas are rare. In this report, we present a case of pituitary adenoma of two different cell populations, Pit-1 and SF-1, and an adenoma and craniopharyngioma collision tumor with coexisting Graves' disease. The patient had a 16-mm pituitary tumor with pituitary stalk calcification and optic chiasm compression but no visual dysfunction. Based on hormonal profile results, the tumor in the sella was considered a nonfunctioning pituitary adenoma; nevertheless, the pituitary stalk was invaded by a different lesion, which was later confirmed to be a craniopharyngioma. Using an endoscopic endonasal approach, the pituitary adenoma was removed; however, a small remnant remained medial to the right cavernous sinus. Because the pituitary stalk lesion was isolated from the pituitary adenoma, it was preserved to maintain pituitary function. Three years after the initial surgery, the patient suffered from Graves' disease and was treated with antithyroid medications. However, the intrasellar residual and pituitary stalk lesions gradually increased in size. A second surgery was performed, and the residual intrasellar and stalk lesions were completely removed. As per the initial and second histopathologies, the pituitary adenoma comprised different cell groups positive for thyroid-(TSH) and follicle-stimulating hormones, and each cell group was positive for Pit-1 and SF-1. The pituitary stalk lesion was an adamantinomatous craniopharyngioma. We believe that TSH-producing adenoma was involved in the development of Graves' disease or that treatment for Graves' disease increased TSH-producing adenoma., Competing Interests: All authors have no conflicts of interest to declare., (© 2023 The Japan Neurosurgical Society.)

Awake surgery for gliomas has become a widely accepted neurosurgical method worldwide. However, it is applied mainly to restore speech and simple motor functions, and intraoperative applications to restore higher brain functions have not been established yet. Preserving these functions is crucial to restoring the normal social lives of patients postoperatively. In this review article, we focused on preserving spatial attention and higher motor functions, and discussed their neural basis, as well as, the application of awake surgery practices using effective tasks. For spatial attention, the line bisection task is the most popular and reliable; however, other tasks, such as exploratory tasks, can be used, depending on the location of the brain. For higher motor functions, we developed two tasks: 1) the PEG & COIN task, which evaluates grasping and approaching skills, and 2) the sponge-control task, which assesses somatosensory-dependent movement. Although scientific knowledge and evidence are still limited in this field of neurosurgery, we believe that expanding our knowledge about higher brain functions and developing specific and efficient intraoperative tasks to evaluate them will eventually preserve patients'quality of life.

Neurofibromatosis type 2(NF2)is a hereditary condition that causes bilateral vestibular schwannomas(VS), multiple schwannomas, and meningiomas. The prognosis is poor because the multiplicity of the tumors leads to a progressive decline in the quality of life, deafness, and death in an early age. NF2 is caused by a disorder in the tumor suppressor gene NF2 , which encodes the merlin protein. Although it is an autosomal dominant disease, more than half of cases are presumed to be de novo caused by somatic mosaicism, the diagnosis rate of which has been improved by the recently introduced technology of targeted deep sequencing of DNA from multiple tissues. No chemotherapeutic drugs for treating NF2-related VS are available at present, and surgery and radiotherapy remain the only therapeutic options. Recently, a randomized, double-blind, multicenter clinical trial has started in Japan to verify the efficacy and safety of bevacizumab, a humanized monoclonal antibody that targets vascular endothelial growth factor, in treating NF2-related VS.

Prosthetic valve endocarditis (PVE) can cause large cerebral vessel occlusion. Many reports suggested that mechanical thrombectomy (MT) is effective and useful for early diagnosis from the histopathological findings of thrombus. We present the case of a 62-year-old man, with a history of prosthetic aortic valve replacement and pulmonary vein isolation for his atrial fibrillation, who developed a high fever and an acute neurological deficit, with left hemiplegia and speech disorder. He was diagnosed as having an acute right middle cerebral artery embolism and underwent an MT. The embolic source was found to be a PVE vegetation. However, histopathological analysis of the thrombus could not detect the actual diagnosis. Although he was treated for bacterial endocarditis, his blood culture revealed a rare fungal infection with Exophiala dermatitidis not until >3 weeks after admission. Subsequently, a ß-D-glucan assay also indicated elevated levels. Although he underwent an aortic valve replacement on day 36, MRI showed multiple minor embolic strokes till that day. Early diagnosis of fungal endocarditis and detection of the causative pathogen are still challenging, and the disease has a high risk of occurrence of early and repeated embolic stroke. In addition to clinical findings and pathological studies, ß-D-glucan assay might be a good tool for the diagnosis and evaluation of fungal endocarditis., Competing Interests: Conflicts of Interest Disclosure The authors declare that there is no conflict of interest., (© 2021 The Japan Neurosurgical Society.)

Objective: We propose a novel method that predicts facial nerve function (FNF) calculated from the drop and recovery of facial motor evoked potential (FMEP) amplitude ratio during the surgery of cerebellopontine angle tumors., Methods: We enrolled 73 patients with cerebellopontine angle tumor, and used a biphasic, constant current, and suprathreshold stimulation (BCS) protocol to record FMEP of the orbicularis oris. We measured the intraoperative minimum-to-baseline amplitude ratio (MBR), the final-to-baseline amplitude ratio (FBR), and the recovery value (RV). RV was measured by subtracting MBR from FBR. Using those values, we evaluated FNF both at early postoperative (EP) and late postoperative (LP) periods., Results: We successfully obtained 62 FMEP readings. Facial palsies occurred in 22 patients during the EP period, and 14 patients recovered during the LP period. Both MBR and FBR showed a significant correlation with FNF in the EP period. RV showed a good predictive power of FNF recovery during the LP period for the first time., Conclusions: RV is a new and useful predictor of FNF recovery. MBR can be an intraoperative predictor of FNF in the EP period., Significance: FNF outcome in the early and late postoperative periods can be predicted by FMEP., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved.)

A few studies have identified the structural connection between the premotor area and the lateral prefrontal cortex (DLPFC) as the frontal longitudinal system (FLS). This study investigated the existence of a direct segment (none U-fibre) of the superior part of the FLS (sFLS), which connects the dorsal premotor cortex (PMd) and DLPFC and analysed its asymmetry and termination point patterns. A dataset of diffusion-weighted images from 48 subjects was used for generalised q-sampling imaging tractography. Additionally, a white-fibre dissection was conducted in two right hemispheres. An analysis of spatial location, termination points, laterality, and correlation with the subjects' gender or handedness was performed. The sFLS was found to have a deeper longitudinal bundle directly connecting the PMd and DLPFC. The bundle is referred to hereafter as the superior frontal longitudinal tract (SFLT). The SFLT was reconstructed in 100% of right and 88% of left hemispheres. It exhibited variable patterns in different subjects in their posterior terminations. In addition, it was found to possess a complicated spatial relationship with the adjacent bundles. The SFLT was revealed successfully in two cadaveric right hemispheres, where the posterior terminations were found to originate in the PMd independent of the superior longitudinal fasciculus.

Objective: Motor evoked potentials(MEPs)have been developed and utilized as safe surgical procedures. A correlation between the threshold intensity of direct stimulation MEPs and the distance of the corticospinal tract(CST)has been already established. However, MEPs are affected by anesthesia and patient-related conditions. Here, we describe a unique technique to avoid these effects., Method: When tumors developed in proximity to the CST, the transcortical MEP monitoring was done by placing grid electrodes on the primary motor cortex continuously while direct subcortical MEP mapping was conducted with a monopolar probe. The ratios of the subcortical to the transcortical stimulation intensity were calculated. The point at which the ratios reached 50% was defined as the surgical excision limit., Discussion: MEPs are affected by anesthesia, paralysis, body temperature, and other factors. By measuring the ratio of the cortical stimulation intensity instead of the absolute value of the white matter stimulation intensity, various affecting factors can be avoided, and more accurate monitoring can become possible., Conclusion: By calculating the ratio of subcortical to cortical stimulation intensity, the corticospinal tract mapping is less likely to be influenced by the stimulation condition or facility setup, and this warrants further investigation.

Background: Sinking skin flap syndrome or paradoxical brain herniation is an uncommon neurosurgical complication, which usually occurs in the chronic phase after decompressive craniectomy. We report a unique case presenting with these complications immediately after decompressive craniectomy for severe traumatic brain injury., Case Description: A 65-year-old man had a right acute subdural hematoma (SDH), contusion of the right temporal lobe, and diffuse traumatic subarachnoid hemorrhage with midline shift to the left side. He underwent an emergency evacuation of the right SDH with a right decompressive frontotemporal craniectomy. Immediately after the operation, his neurological and computed tomography (CT) findings had improved. However, within 1 h after the surgery, his neurological signs deteriorated. An additional follow-up CT showed a marked midline shift to the left, i.e., paradoxical brain herniation, and his skin flap overlying the decompressive site was markedly sunken. We immediately performed an urgent cranioplasty with the right temporal lobectomy. He responded well to the procedure. We suspected that a cerebrospinal fluid leak had caused this phenomenon., Conclusion: Decompressive craniectomy for severe traumatic brain injury can lead to sinking skin flap syndrome and/or paradoxical brain herniation even in the acute phase. We believe that immediate cranioplasty allows the reversal of such neurosurgical complications., Competing Interests: There are no conflicts of interest.

A 60-year-old man was admitted to our hospital because of abdominal pain and disturbed consciousness. Head magnetic resonance imaging showed right vertebral artery dissection and abdominal enhanced computed tomography showed dissection of the superior mesenteric artery. The patient was diagnosed as having fibromuscular dysplasia (FMD) based on conventional angiography. Although multiple vascular bed involvement is observed in approximately 40% of FMD patients, reports of sequential symptomatic dissections in various vascular beds are rare. Patients with FMD and dissection require close observation, and hemodynamic stabilization may prevent not only the further development of dissection, but also subsequent dissection of other arteries.