Hiroshi Nagashima
Teikyo University
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Featured researches published by Hiroshi Nagashima.
Stroke | 2004
Kazuhiro Ohwaki; Eiji Yano; Hiroshi Nagashima; Masafumi Hirata; Tadayoshi Nakagomi; Akira Tamura
Background and Purpose— The association between elevated blood pressure (BP) and hematoma enlargement in acute intracerebral hemorrhage (ICH) has not been clarified. We investigated the association between maximum systolic BP (SBP) and hematoma enlargement, measuring SBP between a baseline and a second CT scan in patients with hypertensive ICH. Methods— We assessed 76 consecutive patients with hypertensive ICH retrospectively. We usually attempted to lower SBP below targets of 140, 150, or 160 mm Hg. Recordings of serial BP from admission until the second CT scan were assessed. A neuroradiologist, who was not informed of the aim of this study, reviewed CT films. Hematoma enlargement was defined as an increase in volume of ≥140% or 12.5 cm3. Results— Hematoma enlargement occurred in 16 patients. Maximum SBP was significantly associated with hematoma enlargement (P = 0.0074). A logistic regression model for predicting hematoma enlargement was constructed with the use of maximum SBP, hematoma volume, and Glasgow Coma Scale score at admission. After adjustment for these factors, maximum SBP was independently associated with hematoma enlargement (odds ratio per mm Hg, 1.04; 95% CI, 1.01 to 1.07). Target SBPs of ≥160 mm Hg were significantly associated with hematoma enlargement compared with those of ≤150 mm Hg (P = 0.025). Conclusions— Our findings suggest that elevated BP increases the risk of hematoma enlargement. Efforts to lower SBP below 150 mm Hg may prevent this risk.
Stroke | 1991
Akira Tamura; Y Tahira; Hiroshi Nagashima; Takaaki Kirino; O Gotoh; S Hojo; Keiji Sano
We investigated shrinkage of the ipsilateral thalamus following infarction in the territory of the middle cerebral artery in 33 patients who were admitted less than or equal to 2 days after the stroke and who were followed by computed tomography for greater than 1 year with no recurrences. The thalamic area was measured on the computed tomograms, and the ratio of the ipsilateral area to the contralateral area was calculated. All values were compared with values from the initial computed tomogram taken less than or equal to 2 days after the stroke. The values of the ratio on follow-up computed tomograms decreased gradually in 15 patients. In these cases, the area of the ipsilateral thalamus was significantly reduced after 1 year (p less than 0.01) and marked atrophy was observed. These results demonstrate the significance of remote changes over a long period of time after focal cerebral infarction.
Stroke | 1994
Makoto Hirakawa; Akira Tamura; Hiroshi Nagashima; Hitoshi Nakayama; Keiji Sano
Background and Purpose The purpose of this study was to investigate the behavioral changes, in particular retention of memory, after focal cerebral ischemia in rats. Methods Ischemia was produced by permanent occlusion of the left middle cerebral artery (MCA). For quantitative behavioral analysis, one-trial passive avoidance response and active avoidance response with the discrete lever-press avoidance procedure were observed. One group of animals was trained once to learn the passive avoidance task 1 day before surgery. The response latency was examined 4 and 14 days after surgery. The second group was trained to learn the active avoidance task for 2 weeks before surgery. The avoidance rate was examined 3 and 14 days after surgery. Results The MCA-occluded group showed significant failure of memory retention in both of these tasks (P<.01). The nonoperated group and sham-operated group showed no definite memory failure. Conclusions Retention of memory in the passive avoidance response and the active avoidance response was disturbed after left MCA occlusion in the rat. These results strongly suggest that this model can be used to assess memory disturbance after focal cerebral ischemia.
Neurological Research | 1997
Kensuke Kawai; Hiroshi Nagashima; Kohji Narita; Tadayoshi Nakagomi; Hitoshi Nakayama; Akira Tamura; Keiji Sano
We retrospectively evaluated efficacy and risk of external ventricular drainage which was performed in early management of high grade subarachnoid hemorrhage. Acute ventricular drainage was performed on 36.6% of 93 patients with grade V subarachnoid hemorrhage. The percentage of patients whose GCS improved following ventricular drainage were 14.3% from GCS 3, 61.5% from GCS 4, 42.9% from GCS 5 and 42.9% from GCS 6. The occurrence rate of rebleeding was approximately three-fold higher in patients who underwent ventricular drainage than in patients who did not. Aneurysmal surgery performed after ventricular drainage, compared with acute aneurysmal surgery, resulted in the smaller percentage of patients who became persistently vegetative and in the larger percentage of patients who became severely disabled, while it did not change the percentage of patients who resulted in favorable outcome and death. These results of retrospective study suggested that ventricular drainage performed on grade V subarachnoid hemorrhage increased the risk of rebleeding and did not increase the percentage of patients who resulted in favorable outcome although it reduced the percentage of patients who resulted in persistent vegetative state.
Acta neurochirurgica | 2001
Tadayoshi Nakagomi; Kiyoshi Takagi; K. Narita; Hiroshi Nagashima; Akira Tamura
Cerebral vasospasm is still one of the major causes of mortality and morbidity (M & M) in patients with subarachnoid hemorrhage (SAH) [1]. In spite of intense and extensive investigation over the past four decades, the optimal treatment of cerebral vasospasm has not yet been established. Clinical studies have clearly demonstrated the relationship between the location and volume of the subarachnoid clots and the incidence, distribution, and severity of vasospasm [3, 4, 11]. In 1988, Kodama et al reported that cisternal irrigation therapy with urokinase and ascorbic acid was effective in preventing cerebral vasospasm [5]. In 1990, Suzuki et al demonstrated that head-shaking method enhanced the fibrinolysis in cisternal irrigation [10]. In January 1994, we combined these two methods in order to achieve better outcome in Fisher CT group 3 patients and started cisternal irrigation therapy with urokinase combined with head-shaking, i.e., cisternal washing therapy.
Medical Molecular Morphology | 2014
Akira Matsuno; Mineko Murakami; Katsumi Hoya; Shoko M. Yamada; Shinya Miyamoto; So Yamada; Jae-Hyun Son; Hajime Nishido; Fuyuaki Ide; Hiroshi Nagashima; Mutsumi Sugaya; Toshio Hirohata; Akiko Mizutani; Yudo Ishii; Shigeyuki Tahara; Akira Teramoto; R. Yoshiyuki Osamura
There have been several reports of temozolomide (TMZ) treatment of pituitary carcinomas and atypical adenomas. O6-methyl-guanine-DNA methyltransferase is not the sole molecule determining the sensitivity to TMZ in pituitary carcinomas and atypical adenomas. The Japan Society of Hypothalamic and Pituitary Tumors study suggests that MSH6, one of mismatch repair pathway enzyme, fulfills a contributory role to the efficacy of TMZ treatment for pituitary carcinomas and atypical adenomas. The preserved MSH6 function might be essential for the responsiveness to TMZ treatment in pituitary carcinomas and atypical adenomas.
Acta Histochemica Et Cytochemica | 2013
Akira Matsuno; Mineko Murakami; Katsumi Hoya; Shoko M. Yamada; Shinya Miyamoto; So Yamada; Jae-Hyun Son; Hajime Nishido; Fuyuaki Ide; Hiroshi Nagashima; Mutsumi Sugaya; Toshio Hirohata; Akiko Mizutani; Yudo Ishii; Shigeyuki Tahara; Akira Teramoto; R. Yoshiyuki Osamura; Kazuto Yamazaki; Yasuo Ishida
Skull base metastasis from differentiated thyroid carcinoma including follicular thyroid carcinoma (FTC) and papillary thyroid carcinoma (PTC) is a rare clinical entity. Eighteen FTC cases and 10 PTC cases showing skull base metastasis have been reported. The most common symptom of skull base metastasis from FTC and PTC is cranial nerve dysfunction. Bone destruction and local invasion to the surrounding soft tissues are common on radiological imaging. Skull base metastases can be the initial clinical presentation of FTC and PTC in the presence of silent primary sites. The possibility of skull base metastasis from FTC and PTC should be considered in patients with the clinical symptoms of cranial nerve dysfunction and radiological findings of bone destruction. A variety of genetic alterations in thyroid tumors have been identified to have a fundamental role in their tumorigenesis. Molecular histochemical studies are useful for elucidating the histopathological features of thyroid carcinoma. Recent molecular findings may provide novel molecular-based treatment strategies for thyroid carcinoma.
Acta neurochirurgica | 2011
Tadayoshi Nakagomi; Kazuhide Furuya; Hiroshi Nagashima; Junichi Tanaka; Teruyuki Ishii; Shigehiko Takanashi; Takeyuki Shinohara; Fumihiro Watanabe; Akiko Ogawa; Norio Fujii; Akira Tamura
In 1994, we started cisternal washing therapy (CWT) using urokinase combined with head-shaking method in order to prevent cerebral vasospasm. In this paper, we showed the surgical procedure for CWT and reported the effect of this therapy in preventing vasospasm following SAH. A total of 332 consecutive cases with Fisher group 3 SAH since 1988 were analyzed. Of these patients, 118 cases (56 cases before 1994 and 62 cases after 1994) had not CWT, and, 214 cases after 1994 had this therapy. All of these patients had clipping surgery within 3 days following SAH, and had postoperative management both with normovolemia and normal to mild hypertension. In these two groups, the incidence of symptomatic vasospasm (transiently symptomatic vasospasm without infarction), cerebral infarction due to vasospasm on CT, and mortality and morbidity (M&M) due to vasospasm were analyzed. In the group without CWT, the incidences of symptomatic vasospasm, cerebral infarction on CT, and M&M due to vasospasm were 4.2%, 28.8%, and 17.8%, respectively. On the other hand, in the group with CWT, they were 3.7%, 6.5%, and 2.8%, respectively. In the patients with CWT, the incidence of cerebral infarction on CT due to vasospasm and M&M due to vasospasm were significantly (p < 0.05) decreased. CWT was effective in preventing cerebral vasospasm.
British Journal of Neurosurgery | 2010
Kazuhiro Ohwaki; Eiji Yano; Hiroshi Nagashima; Masafumi Hirata; Tadayoshi Nakagomi; Akira Tamura
Object. Lowering the blood pressure (BP) of patients with intracerebral haemorrhage (ICH) can prevent haematoma enlargement but may also promote secondary infarction in areas adjacent to the haematoma, which can lead to neurological deterioration. Little is known about the effects of low BP on early neurological deterioration (END). We conducted a retrospective study to determine whether low BP after admission was associated with END in patients with acute ICH. Methods. We investigated 100 consecutive patients diagnosed with spontaneous ICH. We obtained data on minimum systolic blood pressure (SBP) in the 24 h after admission and related factors and assessed END in this time window. Results. END occurred in 38 patients. The frequencies of END by minimum SBP quartile were 52% ( ≤ 100 mmHg), 29% (100–120 mmHg), 14% (120–130 mmHg), and 48% ( > 130 mmHg). A logistic regression model for predicting END was developed using SBP at admission, Glasgow Coma Scale at admission, haematoma volume, minimum SBP, and squared minimum SBP. A U-shaped relationship between minimum SBP and END (p = 0.02) was observed, with the lowest risk for END at a minimum SBP of 123 mmHg. The curve was nearly flat for a minimum SBP of 115–130 mmHg, indicating that the risk of END is relatively low across this range of minimum SBPs. Conclusions. Our findings suggest that a minimum SBP of approximately 120–125 mmHg after admission is associated with a beneficial impact on a reduced risk of END.
Neurocritical Care | 2006
Kazuhiro Ohwaki; Eiji Yano; Hiroshi Nagashima; Masafumi Hirata; Tadayoshi Nakagomi; Akira Tamura
IntroductionLittle information is available on the efficacy of aggressive treatment such as surgery in improving the outcome of severely affected patients after supratentorial intracerebral hemorrhage (ICH). Our objective was to assess the effect of hematoma removal and ventricular drainage on the mortality of patients with severe primary supratentorial ICH. MethodsWe studied 103 consecutive patients who were admitted to the intensive care unit and diagnosed with primary supratentorial ICH. The impacts of clinical factors on 30-day mortality were assessed, including surgery, Glasgow Coma Scale (GCS) score and pupillary abnormality at admission, hematoma volume, and other related factors.ResultsThe 30-day mortality rate was 42%, and the median time between admission and death was 3 days (range: 1 to 27 days). Hematoma removal and ventricular drainage, within the first 24 hours of admission, were performed on 11 and 17 patients, respectively. Two patients who were treated with removal and four with drainage died. A logistic regression model for predicting 30-day mortality was performed. After controlling for GCS score, pupillary abnormality, hydrocephalus, and hematoma volume, hematoma removal was identified as an independent predictor of survival (odds ratio [OR], 0.12; 95% confidence interval [CI], 0.02 to 0.92). Ventricular drainage also tended to decrease mortality rate greatly (OR, 0.31; 95% CI, 0.06 to 1.76). Patients with GCS scores of 3 or 4 were 4.01 times more likely to die (95% CI, 1.13 to 14.26) than those with GCS of at least 5.ConclusionsHematoma removal may reduce the mortality rate of patients with severe supratentorial ICH.