Publications by authors named "Eiji Kohmura"

Pencil-beam presaturation (BeamSAT) magnetic resonance imaging (MRI) produces selective magnetic resonance angiography (MRA) images of specific arteries, including the unilateral internal carotid artery (ICA-selective MRA) or vertebral artery (VA-selective MRA). We evaluate the influence of flow pattern, visualized using BeamSAT MRI, on preoperative cerebral hemodynamic status and postoperative hyperperfusion syndrome (HPS). Patients undergoing carotid artery stenting or carotid endarterectomy were categorized into two groups to evaluate flow pattern.

View Article and Find Full Text PDF

Objective: Delayed facial palsy (DFP) is a common and unique complication after resection of vestibular schwannoma (VS). Few studies have focused on the clinical question of whether patients with DFP can be expected to have the same long-term prognosis in terms of facial nerve function as those without DFP based on their facial nerve function immediately postoperatively. This study aimed to clarify the clinical impact of DFP on the long-term functional status of the facial nerve after VS resection.

View Article and Find Full Text PDF

Objective: Koos grade 4 vestibular schwannoma (KG4VS) is a large tumor that causes brainstem displacement and is generally considered a candidate for surgery. Few studies have examined the relationship between morphological differences in KG4VS other than tumor size and postoperative facial nerve function. The authors have developed a landmark-based subclassification of KG4VS that provides insights into the morphology of this tumor and can predict the risk of facial nerve injury during microsurgery.

View Article and Find Full Text PDF

Objective: Carotid stenosis can lead to both cognitive impairment (CI) and ischemic stroke. Although carotid revascularization surgery, which includes carotid endarterectomy (CEA) and carotid artery stenting (CAS), can prevent future strokes, its effect on cognitive function is controversial. In this study, the authors examined resting-state functional connectivity (FC) in carotid stenosis patients with CI undergoing revascularization surgery, with a particular focus on the default mode network (DMN).

View Article and Find Full Text PDF

Objective: Preservation of neurological function is a priority when performing a resection of a vestibular schwannoma (VS). Few studies have examined the radiographic value of a fundal fluid cap-i.e.

View Article and Find Full Text PDF
Article Synopsis
  • The prognosis for non-hemorrhagic vertebral artery dissection is generally positive, but treatment may be needed if complications like stenosis or aneurysm develop.
  • This case report highlights a patient who underwent successful stent implantation in the posterior inferior cerebellar artery (PICA) to address severe stenosis and aneurysm-related issues stemming from vertebral artery dissection.
  • Following the procedure, the patient experienced immediate relief from neck pain and showed improved PICA condition and reduced aneurysm size during follow-up, suggesting stent placement in PICA may be a viable treatment option.
View Article and Find Full Text PDF

Background: Symptomatic vasospasm (SVS) is a major cause of morbidity and mortality in aneurysmal subarachnoid hemorrhage (SAH), and serum sodium frequently decreases before SVS. Serum sodium changes might be regulated by sodium metabolism-related hormones. This multi-institutional prospective cohort study therefore investigated the measurement of sodium metabolism-related hormones to elucidate the pathophysiology of serum sodium changes in SAH.

View Article and Find Full Text PDF

Purpose: The objective of this study was to evaluate our 12-year experience in treating Borden type III transverse-sigmoid sinus (TSS) dural arteriovenous fistulas (DAVFs) and discuss the technical aspects of ipsilateral and contralateral transvenous embolization (TVE) approaches.

Methods: We retrospectively reviewed charts of consecutive patients with TSS DAVF treated with multimodal treatment between April 2008 and March 2020. The baseline patient characteristics, imaging data, details of procedure, data sets of sinus pressure monitoring, and clinical results were systematically collected.

View Article and Find Full Text PDF

Objective: Postoperative headache (POH) is a disturbing symptom following vestibular schwannoma (VS) resection. However, there are currently no treatment guidelines. The aim of this study was to evaluate the usefulness of symptom-based opioid-free treatments for persistent POH following VS resection.

View Article and Find Full Text PDF

Intracranial artery occlusion due to a foreign body is a complication associated with cardiac surgery that is treated by various techniques. However, little is known about appropriate strategies for symptomatic intracranial artery stenosis due to an unknown embolic source. We reported a case of middle cerebral artery (MCA) stenosis after mitral valve repair (MVR) for infective endocarditis (IE).

View Article and Find Full Text PDF

Objective: Epilepsy in glioblastoma patients significantly reduces their quality of life; however, little is known about the association between predicting epilepsy and metabolites in tumors. In this study, we used 3.0-T magnetic resonance imaging and H-magnetic resonance spectroscopy (MRS) to quantify metabolite concentrations in patients with varying epilepsy histories.

View Article and Find Full Text PDF

Purpose: To investigate the oncological outcomes of orbital malignant tumors invading the skull base.

Methods: A retrospective analysis was conducted on 16 patients with orbital malignant tumors invading the skull base. Eleven patients were treated with skull base surgery, four patients were treated with particle therapies, and one patient was treated with chemoradiotherapy (CRT) as initial treatment.

View Article and Find Full Text PDF

Each year, the Japan Neurosurgical Society (JNS) reports up-to-date statistics from the Japan Neurosurgical Database regarding case volume, patient demographics, and in-hospital outcomes of the overall cohort and neurosurgical subgroup according to the major classifications of main diagnosis. We hereby report patient demographics, in-hospital mortality, length of hospital stay, purpose of admission, number of medical management, direct surgery, endovascular treatment, and radiosurgery of the patients based on the major classifications and/or main diagnosis registered in 2018 and 2019 in the overall cohort (523283 and 571143 patients, respectively) and neurosurgical subgroup (177184 and 191595 patients, respectively). The patient demographics, disease severity, proportion of purpose of admission (e.

View Article and Find Full Text PDF

Background: Microvascular decompression (MVD) is the most effective procedure for the long-term management of trigeminal neuralgia (TGN). However, retrospective and single-center studies are inherently biased, and there are currently no prospective, multicenter studies.

Objective: To evaluate the short- and long-term outcomes and complications in patients with TGN who underwent MVD at specialized Japanese institutions.

View Article and Find Full Text PDF

Background: The thin-walled regions (TIWRs) of intracranial aneurysms have a high risk of rupture during surgical manipulation. They have been reported to be predicted by wall shear stress and pressure (PS) based on computational fluid dynamics analysis, although this remains controversial. In this study, we investigated whether the oscillatory shear index (OSI) can predict TIWRs.

View Article and Find Full Text PDF

Carotid endarterectomy (CEA) and carotid artery stenting (CAS) are recommended for high stroke-risk patients with carotid artery stenosis to reduce ischemic events. However, we often face difficulty in determining the best treatment strategy. We aimed to develop an accurate post-CEA/CAS outcome prediction model using machine learning that will serve as a basis for a new decision support tool for patient-specific treatment planning.

View Article and Find Full Text PDF

Fast-growing tumors satisfy their bioenergetic needs by supplementing glucose with alternative carbon sources. Cancer stem cells are the most versatile and robust cells within malignant tumors. They avoid potentially lethal metabolic and other types of stress through flexible reprogramming of relevant pathways, but it has remained unclear whether alternative carbon sources are important for the maintenance of their tumor-propagating ability.

View Article and Find Full Text PDF

Background: We previously reported that heat shock protein 27 (HSP27) phosphorylation plays an important role in the activation of glucose-6-phosphate dehydrogenase (G6PD), resulting in the upregulation of the pentose phosphate pathway and antioxidant effects against cerebral ischemia-reperfusion injury. The present study investigated the effect of geranylgeranylacetone, an inducer of HSP27, on ischemia-reperfusion injury in male rats as a preliminary study to see if further research of the effects of geranylgeranylacetone on the ischemic stroke was warranted.

Methods: In all experiments, male Wistar rats were used.

View Article and Find Full Text PDF

Intracranial vessel dissection is a procedural complication associated with endovascular treatment. However, there have been few reports on its potential causes and management during mechanical thrombectomy. In approximately 250 cases of mechanical thrombectomy over the past 5 years at our institution, iatrogenic intracranial dissection occurred in 2 patients (0.

View Article and Find Full Text PDF
Article Synopsis
  • * A study analyzed the relationship between the size of this corridor (supra-eustachian triangle - SET) and the ability to successfully remove tumors (extent of resection) in 15 surgeries involving various types of tumors.
  • * Results showed that a larger SET size was associated with higher chances of successfully removing the tumor, particularly in cases with severe extension beyond the midpoint of the internal carotid artery, highlighting the importance of individual anatomical differences in surgical planning.
View Article and Find Full Text PDF

Background: Microvascular decompression (MVD) is the most effective procedure for hemifacial spasm (HFS). MVD results from nonspecialized or low-volume institutes are not always reliable. Most studies on MVD for HFS are retrospective and single centered; to the best of our knowledge, no prospective, multicenter studies exist.

View Article and Find Full Text PDF

Cancer cells optimize nutrient utilization to supply energetic and biosynthetic pathways. This metabolic process also includes redox maintenance and epigenetic regulation through nucleic acid and protein methylation, which enhance tumorigenicity and clinical resistance. However, less is known about how cancer cells exhibit metabolic flexibility to sustain cell growth and survival from nutrient starvation.

View Article and Find Full Text PDF
Article Synopsis
  • The ketogenic diet (KD) is a high fat, low carbohydrate diet that mimics starvation, leading to the production of ketone bodies.
  • Combining KD with Bevacizumab (Bev), a drug that inhibits blood vessel growth in tumors, significantly reduces glucose supply to tumors, resulting in slower tumor growth and longer survival in mouse models.
  • The analysis showed that KD enhances the effectiveness of Bev against glioblastoma by lowering microvascular density and cell proliferation markers, indicating potential as a treatment strategy for patients with this type of brain cancer.
View Article and Find Full Text PDF

Accurate diagnosis and treatment of sellar and parasellar inflammatory lesions is difficult. We report six patients with sellar and parasellar inflammatory lesions and impaired visual function, who underwent endonasal endoscopic surgery. These patients included one with aspergillosis, one with hypertrophic pachymeningitis, one patient with abscess, and three with idiopathic granulomatous lesions.

View Article and Find Full Text PDF

Treating carotid blowout syndrome following rupture of giant pseudoaneurysms is difficult because the destroyed parent artery precludes conventional treatment. We present a patient with a ruptured giant pseudoaneurysm that we occluded using a modified internal trapping technique with low-concentration N-butyl-2-cyanoacrylate (NBCA) and a minimum number of coils. An 80-year-old man with a history of chemoradiation therapy for oropharyngeal cancer presented with several episodes of active bleeding from the subsequent tracheostomy site.

View Article and Find Full Text PDF