Masashi Kuwabara

Dr. Masashi Kuwabara

orcid

Research Focus & Metrics

Academic Career Length

10Years (2017-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 January 2017 in Neurologia medico-chirurgica
Verified
Journal Article
Open access
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MKMasashi Kuwabara
Masashi Kuwabara
TSTakashi Sadatomo
Takashi Sadatomo
KYKiyoshi Yuki
Kiyoshi Yuki
KMKeisuke Migita
Keisuke Migita
YIYasutaka Imada
Yasutaka Imada
KKKaoru Kurisu
Kaoru Kurisu
Chronic subdural hematomas (CSDHs) occur often in elderly persons and can occur with mild head trauma. With burr-hole irrigation as standard treatment, symptoms usually improve and can be cured, and outcomes are good, but postoperative recurrences are a common problem. This study investigated the effectiveness and recurrence rates when using artificial cerebrospinal fluid (ACF) instead of normal saline (NS) as an irrigation solution for burr-hole irrigation in patients with CSDH. This prospective study included 234 consecutive patients who underwent initial surgical treatment by burr-hole irrigation for a CSDH between April 2008 and June 2015. The irrigation solution used was changed from NS to ACF in June 2011. Factors examined with regard to recurrence included age, sex, unilateral or bilateral surgery, computed tomography (CT) findings, antiplatelet or anticoagulant drug use, past history, and irrigation solution (NS or ACF). These were analyzed by univariate and multivariate analyses. Univariate analyses (chi-square test) with a significance level <5% showed that recurrence rates were significantly lower in the ACF group than in the NS group (P = 0.003). Multivariate analysis (multiple logistic regression analysis) showed that the risk of recurrence was reduced 3.14-fold in the ACF group compared to the NS group (odds ratio, 3.143; 95% confidence interval, 0.1504–0.6733; P = 0.0028). None of the other factors were significantly different. In burr-hole irrigation for CSDH, the use of ACF instead of NS as an irrigation solution significantly reduces recurrence rates.

4 November 2022 in Neurosurgery
Verified
Journal Article
Open access
MKMasashi Kuwabara
Masashi Kuwabara
Fusao IkawaFusao Ikawa
Fusao Ikawa
NMNobuaki Michihata
Nobuaki Michihata
SSShigeyuki Sakamoto
Shigeyuki Sakamoto
TOTakahito Okazaki
Takahito Okazaki
HYHideo Yasunaga
Hideo Yasunaga
BACKGROUND: Although chronological age is associated with mortality and morbidity after surgery for unruptured cerebral aneurysms (UCAs), there is little evidence regarding an association between the simplified 5-factor modified frailty index (mFI-5) and postoperative outcomes based on age group. OBJECTIVE: To investigate the association of the mFI-5 score with worse outcomes, mortality, and complications in patients after surgery for UCA by chronological age groups using a Japanese national database. METHODS: This study included 32 902 patients with UCAs enrolled in a Japanese national database between 2011 and 2015. Age group (younger than 65 years, 65-74 years, and 75 years or older), sex, UCA location, treatment, medications, Barthel Index (BI), medical history, mFI-5 score, and in-hospital mortality and complications were evaluated. We identified risk factors for worsening BI score, in-hospital mortality, and overall postoperative complications in each age group. RESULTS: In total, 14 465 patients were enrolled in this study. Multivariable analysis showed that elderly groups and patients with an mFI-5 score ≥2 items were associated with worsening BI scores (odds ratio 1.95; 95% CI 1.52-2.51) and in-hospital complications (odds ratio 1.79; CI 1.49-2.15), despite having no association with in-hospital mortality. Multivariable analysis by age groups showed that the mFI-5 score ≥2 items was associated with in-hospital complications in all age groups, unlike chronological age in patients younger than 74 years. CONCLUSION: The mFI-5 score was a more useful associated factor of in-hospital complications than chronological age in patients younger than 74 years undergoing surgery for UCA.

1 March 2020 in World Neurosurgery
Verified
Journal Article
Closed access
MKMasashi Kuwabara
Masashi Kuwabara
TNToshinori Nakahara
Toshinori Nakahara
TMTakafumi Mitsuhara
Takafumi Mitsuhara
KSKoji Shimonaga
Koji Shimonaga
MHMasahiro Hosogai
Masahiro Hosogai
SSShigeyuki Sakamoto
Shigeyuki Sakamoto

Verified
Journal Article
Open access
PDF file
HKHiroshi Kondo
Hiroshi Kondo
DIDaizo Ishii
Daizo Ishii
MKMasashi Kuwabara
Masashi Kuwabara
THTakeshi Hara
Takeshi Hara
KKKaoru Kurisu
Kaoru Kurisu
NHNobutaka Horie
Nobutaka Horie
Background/Objectives: Effective management of aneurysmal subarachnoid hemorrhage (aSAH) requires an evidence-based treatment protocol. This study examines the outcomes of a unified, multicenter protocol emphasizing postoperative clazosentan as the first-line treatment for vasospasm. Methods: A standardized protocol prioritizing systemic management with clazosentan for vasospasm was implemented in April 2023. Cases treated between April 2022 and March 2024 were categorized into four groups: preprotocol fasudil treatment (PrF), preprotocol clazosentan treatment (PrC), postprotocol fasudil treatment (PoF), and postprotocol clazosentan treatment (PoC); these groups were analyzed. Results: Among 407 registered cases, 322 were eligible for analysis (PrF, 128; PrC, 69; PoF, 28; PoC, 97). PoC exhibited significantly lower angiographic vasospasm rates and had a lower incidence of symptomatic vasospasm compared with PrF (p = 0.048, p = 0.057). Logistic regression identified the clazosentan protocol as a predictive factor for vasospasm reduction (p = 0.02, OR 0.46 [0.22–0.94]; p = 0.022, OR 0.38 [0.16–0.91]). PoC experienced less fluid retention than the PrC (p < 0.001). Logistic regression confirmed protocol adherence with protocol reduced complications (p < 0.001, OR 0.24 [0.11–0.52]), included fluid retention (p < 0.001, OR 0.088 [0.03–0.29]). In older patients, no significant differences in vasospasm or complications were observed between PrF and PoC, but a trend toward reduced complications was observed in World Federation of Neurosurgical Societies (WFNS) grade V cases. Conclusions: Clazosentan-first protocol effectively reduces vasospasm and complications in aSAH management. It is also safe for older patients and those with WFNS grade V, offering a promising treatment strategy.

7 June 2022 in European Journal of Radiology
Verified
Journal Article
Closed access
MKMasashi Kuwabara
Masashi Kuwabara
SSShigeyuki Sakamoto
Shigeyuki Sakamoto
TOTakahito Okazaki
Takahito Okazaki
DIDaizo Ishii
Daizo Ishii
MHMasahiro Hosogai
Masahiro Hosogai
NHNobutaka Horie
Nobutaka Horie

21 September 2022 in Clinical Neurology and Neurosurgery
Verified
Journal Article
Closed access
MKMasashi Kuwabara
Masashi Kuwabara
SSShigeyuki Sakamoto
Shigeyuki Sakamoto
TOTakahito Okazaki
Takahito Okazaki
TMTakafumi Mitsuhara
Takafumi Mitsuhara
DIDaizo Ishii
Daizo Ishii
NHNobutaka Horie
Nobutaka Horie