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Dive into the research topics where Masani Nonaka is active.

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Featured researches published by Masani Nonaka.


Journal of Neurosurgery | 2013

Identification of venous sinus, tumor location, and pial supply during meningioma surgery by transdural indocyanine green videography

Tetsuya Ueba; Masakazu Okawa; Hiroshi Abe; Masani Nonaka; Mitsutoshi Iwaasa; Toshio Higashi; Tooru Inoue; Koichi Takano

OBJECT Indocyanine green (ICG) videography is commonly used in the neurosurgical field for minimally invasive neurosurgery. The aim of this study was to evaluate a new intraoperative imaging modality by performing transdural ICG videography during surgery for meningiomas. METHODS Between March 2011 and April 2012, 10 patients with meningiomas received intravenous injection of 12.5 mg ICG just prior to dural opening. The cases comprised 8 convexity meningiomas and 2 foramen magnum meningiomas. Efficacy of the transdural ICG videography was assessed in terms of the tumor volume, the circulation time from the first appearance of the vessel to the appearance of the venous sinus, the tendency to bleed, and the discrimination of the venous sinus. RESULTS The mean tumor volume was 71.6 ± 87.9 ml (the mean is expressed ± SD throughout). The cortical arteries, veins, and the venous sinus were identified by the ICG videography transdurally. The projection of the meningiomas was identified by a shadow (which the authors call the eclipse sign). Total eclipse signs were obtained in 8 cases and partial eclipse signs were obtained in 2 cases; tumor volume in the latter was more than 200 ml. In 5 of 10 cases the adjacent venous sinuses were exposed and were successfully visualized by ICG videography in 5.92 ± 1.05 seconds from the first appearance of the vessel. In 5 of 10 cases the total and the partial eclipse signs were diminished in 3.46 ± 1.31 seconds. The diminishment of the total and the partial eclipse sign was earlier than the visualization of the venous sinus (p = 0.011, t-test), revealing bleeding from the tumor that was observed until coagulation of the feeding arteries from the intracranial arteries. CONCLUSIONS Prior to opening of the dura mater, transdural ICG videography was used successfully to visualize the dural attachment of meningiomas and the venous sinus, resulting in safe and appropriate dural opening. The diminishment of the total and partial eclipse signs may represent significant feeding from the intracranial arteries and a tendency to bleed during resection.


Neurologia Medico-chirurgica | 2015

Hybrid Assistive Limb (HAL) Rehabilitation in Patients with Acute Hemorrhagic Stroke

Toshiyasu Ogata; Hiroshi Abe; Kazuhiro Samura; Omi Hamada; Masani Nonaka; Mitsutoshi Iwaasa; Toshio Higashi; Hiroyuki Fukuda; Etsuji Shiota; Yoshio Tsuboi; Tooru Inoue

The efficacy of hybrid assistive limb (HAL) rehabilitation in the acute phase of stroke remains unclear. The purpose of this study was to evaluate the outcomes of patients with acute intracranial hemorrhage (ICH) who were treated with or without HAL rehabilitation. Among 270 patients with acute ICH from 2009 to 2014, 91 patients with supratentorial ICH were included in this retrospective study. Of these, 14 patients (HAL group) received HAL rehabilitation at approximately 1 week after ICH occurrence, while the remaining 77 patients received usual rehabilitation without HAL (N-HAL group). We obtained various patient data from the hospitals where the patients were moved to for further rehabilitation. Statistical comparisons were performed for the characteristics of the ICH patients, and outcomes between the HAL and N-HAL groups. There were no differences in outcomes between the HAL and N-HAL groups. However, patients with right ICH in the HAL group exhibited a significant association with a functional independence measure (FIM) score of ≥ 110 compared with patients in the N-HAL group (HAL group: 81.8%, N-HAL group: 43.9%, P = 0.04). In patients with right ICH, HAL rehabilitation was associated with improved outcomes as evaluated by the FIM score. Thus, HAL rehabilitation may improve outcomes of acute ICH in appropriately selected patients.


Journal of Clinical Neuroscience | 2013

Safety and feasibility of combined coiling and neuroendoscopy for better outcomes in the treatment of severe subarachnoid hemorrhage accompanied by massive intraventricular hemorrhage

Mitsutoshi Iwaasa; Tetsuya Ueba; Masani Nonaka; Masakazu Okawa; Hiroshi Abe; Toshio Higashi; Tooru Inoue

Subarachnoid hemorrhage (SAH) with intraventricular hemorrhage (IVH) is associated with poor outcomes. The aim of this study was to evaluate the safety and feasibility of combined coiling and neuroendoscopy for treating severe SAH with massive IVH. Between April 2008 and June 2011, 49 patients with a severe SAH were treated at the Department of Neurosurgery, Fukuoka University, Japan; 10 of these patients had a massive IVH with a ruptured aneurysm. All 10 patients (three men and seven women; mean age, 63.1±8.5 years) were treated with coiling and neuroendoscopic removal of the IVH within 2 days of onset. Coiling was successfully performed at a mean volume embolization ratio of 21.8±5.5%. Neuroendoscopic removal of the IVH reduced the mean Graeb score from 10.5±2.0 to 4.8±2.5 (p=0.005). All external drains were removed on day 3. No rebleeding or acute hydrocephalus was noted. The Glasgow Outcome Scale scores at discharge indicated two patients with good recovery, three with moderate disability, four in a vegetative state, and one dead. A good modified Rankin Scale (mRS) score (0-2) at least 6 months later (mean follow-up period, 15.4±9.2 months) was observed for five patients (50%), and a poor mRS score (3-6) was observed for the remaining four patients. Neuroendoscopically removing the IVH from all of the ventricles between the lateral and the fourth ventricle and coiling the ruptured aneurysm is a safe, feasible approach for treating severe SAH with massive IVH.


Pediatric Neurosurgery | 2008

Congenital Medulloblastoma with Atypical MRI Appearance

Fuminari Komatsu; Hitoshi Tsugu; Masani Nonaka; Makoto Tsutsumi; Fumio Yanai; Kou Yukitake; Hidetsuna Utsunomiya; Takeo Fukushima

A 13-day-old female infant was admitted with hydrocephalus that had been diagnosed on prenatal ultrasound at 33 weeks’ gestation. She was delivered by Caesarean section at 34 weeks with an Apgar score of 10. On admission, she weighed 2,103 g. The head circumference was 32.3 cm, and the fontanelle was tense. T1- and T2-weighted MR images revealed an isointense mass occupying the fourth ventricle with multiple cysts in the vermis. The mass was not enhanced after gadolinium administration. CT showed no definite calcification in the lesion. Preoperatively, vermian tumors, including medulloblastoma, ependymoma, astrocytoma, and hamartomas, were considered in the differential diagnosis. Hamartoma was strongly suspected due to the lack of enhancement on MRI. After a suboccipital midline craniotomy, subtotal resection of a soft grayish tumor with areas of hematoma was carried out. The pathological diagnosis was medulloblastoma. Despite chemotherapy, CSF dissemination resulted in death at 11 months. We report this case of congenital medulloblastoma with atypical MRI findings and discuss the clinical characteristics of this lesion.


Journal of Neurological Surgery Reports | 2015

Management of Trigeminal Neuralgia Caused by an Intraneural Spiral Trigeminocerebellar Artery: A Case Report

Naoki Wakuta; Hiroshi Abe; Masani Nonaka; Toshio Higashi; Tetsuya Ueba; Tooru Inoue

The trigeminocerebellar artery (TCA) is a branch of the basilar artery that may have an intraneural course and may cause trigeminal neuralgia. We report a case of trigeminal neuralgia with right vertebral artery aneurysm caused by an intraneural TCA that compressed the trigeminal nerve in multiple places. We performed proximal trapping for the fusiform aneurysm with extra-intracranial bypass to preserve flow of the posterior inferior cerebellar artery, followed by microvascular decompression that successfully changed the course of the TCA. This procedure provided relief from the neuralgia without direct bisection of the trigeminal nerve that may cause severe nerve injury. Reshaping of the course of the artery can achieve good pain relief.


Surgical Neurology International | 2018

Endoscopic surgery via a combined frontal and suboccipital approach for cerebellar hemorrhage

Kenji Yagi; Masani Nonaka; Hiroshi Abe; Koichi Miki; Takashi Morishita; Mitsutoshi Iwaasa; Tooru Inoue

Background: Spontaneous cerebellar hemorrhages (CHs), which frequently require surgical intervention, are life-threatening and can be complicated by intraventricular hemorrhages (IVHs) and obstructive hydrocephalus. Commonly, endoscopic surgery is performed to remove CHs via a suboccipital approach (SA) alone. At our institution, when patients exhibited supratentorial IVH-associated hydrocephalus, we used a combined frontal and suboccipital approach (CA) to evacuate both CHs and supratentorial IVHs. The present study retrospectively evaluated the effectiveness and safety of this CA, as no prior studies examining this approach currently exist. Methods: Twenty-six patients with spontaneous CH were surgically treated at our hospital from April 2009 to March 2016. Twenty-two patients who could independently perform activities of daily living before the onset underwent endoscopic surgery to evacuate the CHs; among these, 13 patients underwent the SA alone, while nine underwent the CA. We assessed and compared the patients’ baseline characteristics, surgical results, and prognosis at 1 month after the intervention between the SA and CA groups. Results: Patients who underwent the CA had significantly poorer consciousness before the surgery owing to IVH extension and obstructive hydrocephalus. However, the surgical results and prognosis at 1 month were not significantly different between the two approaches. The CH-associated IVHs were successfully removed with the CA and resulted in shorter external ventricular drainage (EVD) placement durations. Conclusion: Endoscopic surgery performed via the CA appeared to neutralize the deteriorating effects of CH-associated IVHs. Surgical strategies employing the CA may have the potential to improve the prognosis of patients with CH.


Oncology Letters | 2018

Clinicopathological and genetic characteristics associated with brain metastases from lung adenocarcinoma and utility as prognostic factors

Hiromasa Kobayashi; Makoto Hamasaki; Takashi Morishita; Masayo Yoshimura; Masani Nonaka; Hiroshi Abe; Tooru Inoue; Kazuki Nabeshima

Brain metastases (BM) are common in patients with lung adenocarcinoma, and represent a significant cause of morbidity in the disease. A more comprehensive understanding of the clinicopathological characteristics that serve as prognostic factors for survival in patients with BM from lung adenocarcinoma may aid in informing treatment strategies for this patient population. In the present study, clinicopathological factors, including EGFR mutation status, were evaluated in 59 patients who were diagnosed with BM from lung adenocarcinoma, and underwent BM resection between January 1985 and December 2014 at Fukuoka University Hospital. The most frequent subtype of BM from lung adenocarcinoma was solid adenocarcinoma (57.6%), followed by papillary adenocarcinoma (22.0%) and acinar adenocarcinoma (18.6%). A total of 14 patients (23.7%) exhibited EGFR mutations, which were significantly associated with female sex (9/14, 64.3%), non-smoker status (8/14, 57.1%), BM in the frontal lobes (9/14, 64.3%) and papillary adenocarcinoma (5/14, 35.7%). Statistical analysis revealed a significant association between non-smoker status and BM in the frontal lobes, and more favorable disease prognosis. The results of the present study suggest that histological and genetic analysis of tissue from BM provides information useful for managing treatment of patients with resectable BM arising from lung adenocarcinoma.


Archive | 2018

Potential of Hybrid Assistive Limb Treatment for Ataxic Gait Due to Cerebellar Disorders Including Hemorrhage, Infarction, and Tumor

Hiroshi Abe; Takashi Morishita; Kazuhiro Samura; Kenji Yagi; Masani Nonaka; Tooru Inoue

Cerebellar hemorrhage (CH) is a severe life-threatening disorder, and surgical treatment is often required in an emergency situation. Even in cases in which the surgical procedure is successful, functional recovery is likely to be delayed because of cerebellar symptoms such as ataxia and gait disturbance. Here, we briefly review the efficacy of hybrid assistive limb (HAL) treatment in neurosurgical practice and propose a new comprehensive treatment strategy for CH to facilitate early neurological recovery. We have experienced cases of ataxic gait due to various etiologies, treated with rehabilitation using the HAL, and our data showed that HAL treatment potentially improves ataxic gait and balance problems. HAL treatment seems to be an effective and promising treatment modality for selected cases. Future studies should evaluate gait appearance and balance, in addition to walking speed, to assess improvement in cerebellar symptoms.


Acta Neurochirurgica | 2018

Cerebral and spinal cavernomas associated with Klippel-Trenaunay syndrome: case report and literature review

Takaya Yoshinaga; Kenji Yagi; Takashi Morishita; Hiroshi Abe; Masani Nonaka; Tooru Inoue

Klippel-Trenaunay-Weber syndrome (KTWS) involves a triad of conditions, including cutaneous hemangiomas, venous varicosities, and osseous and soft-tissue hypertrophy of the affected limb. We describe a rare case of multiple cavernomas in the central nervous system in a patient with KTWS. A-64-year-old man with KTWS and a previous brain hemorrhage presented with sudden onset of gait and vesicorectal disturbance. The magnetic resonance imaging scan showed a cavernoma associated with hemorrhage in his lumbosacral spinal cord. Moreover, numerous cavernomas were identified in his brain. He was treated conservatively with no adverse events. Gait disturbance improved, but vesicorectal disturbance did not improve.


Anticancer Research | 2009

Sonodynamic Therapy Consisting of Focused Ultrasound and a Photosensitizer Causes a Selective Antitumor Effect in a Rat Intracranial Glioma Model

Masani Nonaka; Masaaki Yamamoto; Shinichiro Yoshino; Shin-ichiro Umemura; Kazunari Sasaki; Takeo Fukushima

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Mitsutoshi Iwaasa

Memorial Hospital of South Bend

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Toshio Higashi

Memorial Hospital of South Bend

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