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Dive into the research topics where Hajime Maruyama is active.

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Featured researches published by Hajime Maruyama.


Journal of Stroke & Cerebrovascular Diseases | 2012

Clinical review of 37 patients with medullary infarction.

Takuya Fukuoka; Hidetaka Takeda; Tomohisa Dembo; Harumitu Nagoya; Yuji Kato; Ichiro Deguchi; Hajime Maruyama; Yohsuke Horiuchi; Akira Uchino; Susumu Yamazaki; Norio Tanahashi

BACKGROUND Clinical features of medullary infarction were compared between patients with lateral medullary infarction and medial medullary infarction METHODS Thirty-seven patients with medullary infarction (29 with lateral medullary infarction and 8 with medial medullary infarction) who were admitted to our center between April 1, 2007 and March 31, 2010 were examined. Background factors, neurologic signs and symptoms, imaging findings, cause of disease, and outcomes were assessed for patients with lateral and those with medial medullary infarction. RESULTS Examination of the clinical symptoms and neurologic findings suggested that among patients with medial medullary infarction, few demonstrated all of the symptoms of Dejerine syndrome at onset, and many had lesions that were difficult to locate based only on neurologic findings. Both lateral and medial medullary infarction were frequently caused by atherothrombosis. However, cerebral artery dissection was observed in 31% of patients with lateral medullary infarction and 12.5% of those with medial medullary infarction. In 13% of patients with lateral and 37% of patients with medial medullary infarction, magnetic resonance imaging diffusion-weighted images on the day of onset did not show abnormalities, and the second set of diffusion-weighted images confirmed infarction lesions. For lateral medullary infarction, a more rostral lesion location was correlated with a poorer 90-day outcome. For medial medullary infarction, a more dorsal lesion location was correlated with a poorer 90-day outcome. CONCLUSIONS The diagnosis rate of medullary infarction using imaging examinations at onset--particularly medial medullary infarction--is not necessarily high. The imaging examinations need to be repeated for patients who are suspected to have medullary infarction based on neurologic signs and symptoms.


Journal of Neuroradiology | 2014

MRI abnormality of the pulvinar in patients with status epilepticus

Yasuko Ohe; Takeshi Hayashi; Ichiro Deguchi; Takuya Fukuoka; Y. Horiuchi; Hajime Maruyama; Yuji Kato; Harumithu Nagoya; Akira Uchino; Norio Tanahashi

OBJECTIVE Recently, magnetic resonance imaging (MRI) abnormalities of the pulvinar in patients with epilepsy have received greater attention, but their occurrence and features have not been fully elucidated. Therefore, we investigated the clinical and radiological features of patients with epilepsy who presented MRI abnormalities of the pulvinar. PATIENTS AND METHODS We retrospectively investigated 225 consecutive patients who came to our institute because of seizures and underwent an MRI within 24h. The patients who exhibited pulvinar MRI abnormalities, their profile, seizure type, efficacy of medication, and chronological changes of MRI findings were examined. RESULTS Out of the 225 patients who underwent MRI within 24h of seizure, 17 exhibited MRI abnormalities of the pulvinar. All of these 17 patients presented status epilepticus. Bilateral pulvinar diffusion-weighted imaging (DWI) hyperintensity was observed in 3 patients and unilateral pulvinar DWI hyperintensity in the other 14. Out of these 14 patients, 7 exhibited DWI hyperintensity in the ipsilateral cerebral cortex, and 10 patients presented an old lesion due to stroke or trauma. CONCLUSIONS Our results demonstrated that the involvement of the pulvinar in status epilepticus is more frequent than expected and consisted of unilateral or bilateral DWI hyperintensities that may completely normalize. These pulvinar MRI abnormalities possibly reflect the epileptogenic hyperexcitation of different cortical areas through their connections with the pulvinar.


Journal of Stroke & Cerebrovascular Diseases | 2011

Significance of Clinical–Diffusion Mismatch in Hyperacute Cerebral Infarction

Ichiro Deguchi; Hidetaka Takeda; Daisuke Furuya; Kimihiko Hattori; Tomohisa Dembo; Harumitsu Nagoya; Yuji Kato; Takuya Fukuoka; Hajime Maruyama; Norio Tanahashi

In recent years, patient selection for intravenous tissue plasminogen activator (t-PA) therapy based on clinical-diffusion mismatch (CDM) has been closely examined. We investigated the relationship between prognosis and CDM in patients with hyperacute cerebral infarction within 3 hours of onset and compared CDM with diffusion-perfusion mismatch (DPM). Of 122 patients with hyperacute cerebral infarction who visited the hospital within 3 hours of onset between April 2007 and November 2008, 85 patients with cerebral infarction in the anterior circulation who underwent head magnetic resonance imaging diffusion-weighted imaging (DWI)/magnetic resonance angiography (MRA) (51 men and 34 women; average age, 74 ± 10 years) were enrolled. Seventeen of these patients underwent CT perfusion imaging. CDM-positive cases were those with a National Institute of Health Stroke Scale (NIHSS) score ≥ 8 and a DWI-Alberta Stroke Program Early CT Score (DWI-ASPECTS) ≥ 8; CDM-negative cases were those with an NIHSS score ≥ 8 and an ASPECTS-DWI < 8. The other patients were classified as belonging to the NIHSS score < 8 group. Of the 32 CDM-positive cases, 10 received t-PA infusion. These patients had markedly higher modified Rankin Scale scores 90 days after onset compared with the 22 patients who did not receive t-PA infusion. The 8 CDM-positive cases included 4 DPM-positive cases and 4 DPM-negative cases, and a discrepancy was confirmed between CDM and DPM. In all DPM-positive cases, MRA confirmed lesions in major intracranial arteries. CDM may enable more accurate prediction of outcomes in patients with hyperacute cerebral infarction. In addition, the combination of CDM findings and MRA findings (stenosis or occlusion in major intracranial arteries) may be an alternative to DPM for determining the indications for IV t-PA therapy in patients with hyperacute cerebral infarction.


Journal of Stroke & Cerebrovascular Diseases | 2013

The CHA(2)DS(2)-VASc score reflects clinical outcomes in nonvalvular atrial fibrillation patients with an initial cardioembolic stroke.

Ichiro Deguchi; Takeshi Hayashi; Yasuko Ohe; Yuji Kato; Harumitsu Nagoya; Takuya Fukuoka; Hajime Maruyama; Yohsuke Horiuchi; Norio Tanahashi

BACKGROUND Whether the CHA(2)DS(2)-VASc score reflects severity or clinical outcomes in patients with an initial cardioembolic stroke associated with nonvalvular atrial fibrillation (NAVF) was investigated. METHODS This study included 327 patients hospitalized between April 2007 and March 2012 for an initial cardioembolic stroke associated with NVAF with no history of stroke. The National Institutes of Health Stroke Scale (NIHSS) score on admission and clinical outcome (modified Rankin Scale [mRS] score after 90 days) were retrospectively evaluated according to the CHA(2)DS(2)-VASc score. RESULTS CHA(2)DS(2)-VASc scores were 0, 3.1%; 1, 9.1%; 2, 24.5%; 3, 26%; 4, 20.8%; 5, 14.4%; and 6, 2.1%. The median NIHSS scores for CHA(2)DS(2)-VASc scores of 0-6 were 4.5, 8, 8, 10, 11, 17, and 23, respectively. Severity differed according to the CHA(2)DS(2)-VASc score. The clinical outcomes according to the CHA(2)DS(2)-VASc scores were as follows: score 0, mRS scores of 0-2 (80%) and 3-6 (20%); score 1, mRS scores of 0-2 (80%) and 3-6 (20%); score 2, mRS scores of 0-2 (64%) and 3-6 (36%); score 3, mRS scores of 0-2 (48%) and 3-6 (52%); score 4, mRS scores of 0-2 (28%) and 3-6 (72%); score 5, mRS scores of 0-2 (26%) and 3-6 (74%); and score 6, mRS scores of 0-2 (29%) and 3-6 (71%). The clinical outcome worsened as the CHA(2)DS(2)-VASc score increased. On logistic regression analysis, age, NIHSS score on admission, and thrombolytic therapy were related to a clinical outcome. CONCLUSIONS The severity of NVAF-induced initial cardioembolic stroke increased with higher CHA(2)DS(2)-VASc scores, and the outcomes were poor. The present study suggests that the CHA(2)DS(2)-VASc score may be useful not only for the evaluation of stroke risk but also for the prediction of clinical outcomes after stroke.


Journal of Stroke & Cerebrovascular Diseases | 2013

Treatment Outcomes of Tissue Plasminogen Activator Infusion for Branch Atheromatous Disease

Ichiro Deguchi; Takeshi Hayashi; Yuji Kato; Harumitsu Nagoya; Yasuko Ohe; Takuya Fukuoka; Hajime Maruyama; Yohsuke Horiuchi; Norio Tanahashi

BACKGROUND The objective of this study was to evaluate treatment outcomes of tissue plasminogen activator (t-PA) infusion for hyperacute branch atheromatous disease (BAD) within 3 hours after onset. METHODS A total of 152 BAD patients with lenticulostriate artery (LSA) or paramedian pontine artery (PPA) territory infarcts (LSA 114; PPA 38) were hospitalized between April 2007 and June 2012. Of these, 21 BAD patients (LSA 19; PPA 2) arrived at the hospital within 3 hours after onset, and, among these, 8 patients who received t-PA infusion (.6 mg/kg) were included in this study. All BAD patients who received t-PA infusion had LSA territory infarcts. RESULTS Six of 8 patients (75%) had improvement of neurologic findings within 60 minutes after t-PA infusion, but neurologic findings deteriorated within 24 hours in 4 of these patients (67%). In all patients with deterioration, diffusion-weighted imaging after 24 hours revealed infarct expansion. One patient (13%) had symptomatic intracranial hemorrhage. After 3 months, the modified Rankin Scale (mRS) score was 0 to 2 in 6 patients (75%) and 3 to 6 in 2 patients (25%). CONCLUSIONS With t-PA infusion for BAD, symptoms transiently improved, but the rate of symptom deterioration was high. The outcome after 3 months was relatively good.


Journal of Stroke & Cerebrovascular Diseases | 2014

Clinical Outcomes of Persistent and Paroxysmal Atrial Fibrillation in Patients with Stroke

Ichiro Deguchi; Takuya Fukuoka; Takeshi Hayashi; Hajime Maruyama; Yoshihide Sehara; Yuji Kato; Yohsuke Horiuchi; Yuito Nagamine; Hiroyasu Sano; Norio Tanahashi

BACKGROUND We compared the clinical outcomes of persistent atrial fibrillation (PeAF) and paroxysmal atrial fibrillation (PAF) in patients with cardioembolic stroke caused by nonvalvular atrial fibrillation (NVAF) because the nature of the fibrillation can cause persistent cerebral infarction. METHODS We classified 619 of 964 patients hospitalized with cardioembolic stroke between April 2007 and December 2013 within 24 hours of onset as having PeAF (n = 447) and PAF (n = 172) according to a retrospective analysis of their clinical records, including National Institutes of Health Stroke Scale (NIHSS) scores on admission, clinical outcomes (modified Rankin Scale [mRS] scores) at 90 days after admission, and major cerebral artery occlusion. RESULTS The PeAF group was significantly older (P < .001) and had a higher prevalence of hypertension (P = .007), diabetes (P = .039), heart failure (P = .004), previous coronary artery disease (P = .002) and cerebral infarction (P < .001), medication with anticoagulants (P < .001), and elevated blood glucose on admission (P = .002). Neurologic severity assessed by NIHSS scores on admission was significantly worse in the PeAF than in the PAF group (P < .001). Significantly more patients in the PAF group had favorable outcomes (mRS, 0-2) after 90 days (P < .001). The incidence of major cerebral artery occlusion was significantly higher in the PeAF group (P < .001). CONCLUSIONS Patients with PeAF and cardioembolic stroke due to NVAF had more severe neurologic deficits on admission, more frequent major arterial occlusion, and poorer outcomes than those with PAF.


Journal of Stroke & Cerebrovascular Diseases | 2012

Relationship of Obesity to Recanalization after Hyperacute Recombinant Tissue-Plasminogen Activator Infusion Therapy in Patients with Middle Cerebral Artery Occlusion

Ichiro Deguchi; Yasuko Ohe; Takuya Fukuoka; Tomohisa Dembo; Harumitsu Nagoya; Yuji Kato; Hajime Maruyama; Yohsuke Horiuchi; Norio Tanahashi

BACKGROUND This was a retrospective analysis of factors related to recanalization after hyperacute recombinant tissue-plasminogen activator (rt-PA) infusion therapy in patients with middle cerebral artery occlusion. METHODS Of the 50 patients (39 males and 11 females; mean age 70 ± 11 years) with cerebral infarction who were able to undergo diffusion-weighted magnetic resonance imaging (MRI)/magnetic resonance angiography (MRA) of the head within 24 hours of starting rt-PA infusion therapy while hospitalized at our center between April 2007 and October 2010, 23 patients (18 males and 5 females; mean age 71 ± 9.4 years) with hyperacute cerebral infarction with findings of obstruction in the proximal segment of the middle cerebral artery (MCA-M1) served as subjects. RESULTS Of the 23 patients with MCA occlusion, 13 (57%) were recanalized. Analysis of factors related to recanalization revealed a significant difference (P = .019) for obesity (body mass index >25 kg/m(2)), with significantly more obese patients in the nonrecanalized group than in the recanalized group. The study revealed no significant differences in other factors between the 2 groups. CONCLUSIONS The results suggest that obesity may be involved in recanalization after hyperacute rt-PA infusion therapy in patients with MCA occlusion.


European Journal of Neurology | 2012

Usefulness of MRA-DWI mismatch in neuroendovascular therapy for acute cerebral infarction

Ichiro Deguchi; Tomohisa Dembo; Takuya Fukuoka; Harumitu Nagoya; Hajime Maruyama; Yuji Kato; Y. Oe; Y. Horiuchi; Hidetaka Takeda; Norio Tanahashi

Background:  This study evaluated the usefulness of MR angiography (MRA)–diffusion‐weighted imaging (DWI) mismatch in neuroendovascular therapy over 3 h after onset of acute cerebral infarction.


Journal of Stroke & Cerebrovascular Diseases | 2014

Research Article: Clinical Characteristics of Isolated Anterior Cerebral Artery Territory Infarction Due to Arterial Dissection

Yuito Nagamine; Takuya Fukuoka; Takeshi Hayashi; Yuji Kato; Ichiro Deguchi; Hajime Maruyama; Yohsuke Horiuchi; Hiroyasu Sano; Satoko Mizuno; Norio Tanahashi

BACKGROUND Isolated brain infarction in the anterior cerebral artery (ACA) territory is rare, and its etiology has not yet been fully elucidated. Thus, we aimed to determine the etiologic and clinical characteristics of patients with isolated ACA territory infarction due to arterial dissection. METHODS Of 2315 patients with acute cerebral infarction admitted to our hospital between April 2007 and September 2013, 34 patients (1.5%; 28 men, 6 women; mean age, 65 ± 15 years) suffered isolated ACA territory infarction. We performed cranial magnetic resonance (MR) imaging and MR angiography for all the patients. Whenever possible, we also performed 3-dimensional computed tomography angiography, digital subtraction angiography, and MR cisternography to diagnose the stroke subtype. RESULTS The stroke subtypes of the 34 patients with isolated ACA territory infarction were atherothrombotic infarction, cardioembolic infarction, arterial dissection, and unclassified in 11 patients (32%), 11 patients (32%), 11 patients (32%), and 1 patient (3%), respectively. The mean ages at onset were 48 ± 9 and 72 ± 11 years in the dissection and nondissection groups, respectively (P < .001). Headaches were present at onset in 4 patients (36%) and 1 patient (4%) with and without dissection, respectively (P = .026). Blood pressure at onset was significantly higher among patients with dissection (systolic, 179 ± 34 mm Hg; diastolic, 102 ± 17 mm Hg) than among patients without dissection (systolic, 155 ± 30 mm Hg; diastolic, 86 ± 21 mm Hg; P < .05), and d-dimer values were significantly lower among patients with dissection (P = .034). Favorable clinical outcome (modified Rankin Scale score, 0-2) at discharge was achieved in 9 patients (82%) and 10 patients (43%) with and without dissection, respectively (P = .035). CONCLUSIONS Patients with isolated ACA territory infarction demonstrated a relatively high frequency of dissection (32%). Patients with dissection were younger, had a higher frequency of headaches, and demonstrated more favorable prognoses than patients without dissection.


International Journal of Stroke | 2014

CHADS2 score/CHA2DS2-VASc score and major artery occlusion in cardioembolic stroke patients with nonvalvular atrial fibrillation

Ichiro Deguchi; Takeshi Hayashi; Yasuko Ohe; Yuji Kato; Takuya Fukuoka; Hajime Maruyama; Yohsuke Horiuchi; Hiroyasu Sano; Yuito Nagamine; Norio Tanahashi

Objective The associations between the CHADS2 score/ CHA2DS2-VASc score, and the presence of cerebral vessel occlusion on admission were examined in cardioembolic stroke patients with nonvalvular atrial fibrillation. Methods The subjects were 546 consecutive patients hospitalized between April 2007 and December 2012 with onset of cardioembolic stroke associated with nonvalvular atrial fibrillation within 24 h. The associations between the CHADS2 score/CHA2DS2-VASc score and the presence of occluded cerebral vessels on magnetic resonance angiography were evaluated retrospectively. Occluded cerebral vessels were classified into the internal carotid artery, middle cerebral artery (M1, M2), basilar artery, and other (anterior cerebral artery [A1], posterior cerebral artery [P1], vertebral artery). Results Major artery occlusion was seen in 52% of patients with CHADS2 score 0, 52% of patients with score 1, 57% with score 2, 75% with score 3, and 75% with score ≥4. As for the CHA2DS2-VASc score, major artery occlusion was seen in 62% of patients with score 0, 49% with score 1, 53% with score 2, 53% with score 3, 65% with score 4, 71% with score 5, and 82% with score ≥6. The incidence of concurrent major arterial occlusion increased as both scores rose. When classified by occluded blood vessel, the incidence of concurrent internal carotid artery occlusion increased as both the CHADS2 and CHA2DS2-VASc scores increased. Conclusion As the CHADS2 and CHA2DS2-VASs scores increased, the incidence of concurrent major arterial occlusion, particularly internal carotid artery occlusion, increased in patients with cardioembolic stroke associated with nonvalvular atrial fibrillation.

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Norio Tanahashi

Saitama Medical University

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Takuya Fukuoka

Saitama Medical University

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Ichiro Deguchi

Saitama Medical University

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Yuji Kato

Saitama Medical University

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Takeshi Hayashi

Saitama Medical University

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Yohsuke Horiuchi

Saitama Medical University

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Yasuko Ohe

Saitama Medical University

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Hiroyasu Sano

Saitama Medical University

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Tomohisa Dembo

Saitama Medical University

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Yuito Nagamine

Saitama Medical University

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