45 results on '"Oshio K"'
Search Results
2. Acute phase endovascular intervention on a pseudoaneurysm formed due to rupture of an anterior communicating artery aneurysm
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Ito, H., primary, Morishima, H., additional, Onodera, H., additional, Wakui, D., additional, Uchida, M., additional, Sase, T., additional, Oshio, K., additional, and Tanaka, Y., additional
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- 2014
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3. Fast spin-echo imaging in the evaluation of intradural disease of the spine
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Sze, G, Merriam, M, Oshio, K, and Jolesz, F A
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Adult ,Male ,Evaluation Studies as Topic ,Humans ,Comparative Study ,Female ,Dura Mater ,Middle Aged ,Magnetic Resonance Imaging ,Spinal Cord Diseases ,Aged - Abstract
PURPOSE: Fast spin echo (FSE) images were compared with conventional images in 46 patients with intradural spinal disease to determine their accuracy in the detection and delineation of lesions. MATERIALS AND METHODS: The images were interpreted by two neuroradiologists, who read individually. A total of 720 blinded readings formed the basis for this evaluation. A gold standard for each patient was selected, based on the blinded readings of the conventional studies. RESULTS: In the sagittal plane, the FSE sequences were found to have an accuracy of 93% and 93% for the first reader and 93% and 85% for the second reader. For the axial plane, the corresponding figures were 86% and 82% for the first reader and 64% and 77% for the second reader. These figures compared favorably with conventional sequences. Similar delineation of lesions was noted in 78% of cases. In the remaining cases, there were no significant trends. CONCLUSION: Because of these findings, FSE sequences appear as accurate as conventional sequences. In this study, they were capable of supplanting conventional sequences in the evaluation of intradural pathology of the spine in the sagittal plane, although conventional sequences were still preferred in the axial plane.
- Published
- 1992
4. Correction of T2 distortion in multi-excitation RARE sequence
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Oshio, K., primary and Singh, M., additional
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- 1992
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5. The ASYST Software for Scientific Computing
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HARY, D., primary, OSHIO, K., additional, and FLANAGAN, S. D., additional
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- 1987
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6. Development of Machine-learning Model to Predict Anticoagulant Use and Type in Geriatric Traumatic Brain Injury Using Coagulation Parameters.
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Fujiwara G, Okada Y, Suehiro E, Yatsushige H, Hirota S, Hasegawa S, Karibe H, Miyata A, Kawakita K, Haji K, Aihara H, Yokobori S, Inaji M, Maeda T, Onuki T, Oshio K, Komoribayashi N, Suzuki M, and Shiomi N
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- Humans, Aged, Male, Female, Retrospective Studies, Aged, 80 and over, International Normalized Ratio, Partial Thromboplastin Time, Japan, Blood Coagulation drug effects, Vitamin K antagonists & inhibitors, Prothrombin Time, Machine Learning, Brain Injuries, Traumatic blood, Brain Injuries, Traumatic diagnosis, Anticoagulants therapeutic use
- Abstract
This study aimed to investigate the patterns of anticoagulation therapy and coagulation parameters and to develop a prediction model to predict the type of anticoagulation therapy in geriatric patients with traumatic brain injury. A retrospective analysis was performed using the nationwide neurotrauma database of Japan. Elderly patients (≥65 years) with traumatic brain injury. Patients were divided into 3 groups based on their daily anticoagulant medication (none, direct oral anticoagulant [DOAC], and vitamin K antagonist [VKA]), and coagulation parameters were compared in each group. We then developed a machine-learning model to predict the anticoagulant using coagulation parameters and visualized the pattern using a heat map. A total of 495 patients were enrolled and divided into 3 groups: none (n = 439), DOACs (n = 37), and VKA (n = 19). Comparing none to DOAC and DOAC to VKA for prothrombin time-international normalized ratio (PT-INR), the mean difference and 95% confidence intervals (CIs) were 0.38 (95% CI: 0.59-0.17) and 1.56 (95% CI: 1.21-1.90), and for activated partial thromboplastin time (APTT), the mean difference between none to DOAC and DOAC to VKA was 3.46 (95% CI: 0.98-5.94) and 95% CI was 7.39 (95% CI: 3.29-11.48). A prediction model for the type of anticoagulant used by PT-INR and APTT was developed using machine-learning methods, and a heat map visually revealed their relationship with acceptable predictive ability. This study revealed the characteristic patterns of coagulation parameters in anticoagulants and a pilot model to predict anticoagulant use.
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- 2025
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7. A machine learning model to predict neurological deterioration after mild traumatic brain injury in older adults.
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Abe D, Inaji M, Hase T, Suehiro E, Shiomi N, Yatsushige H, Hirota S, Hasegawa S, Karibe H, Miyata A, Kawakita K, Haji K, Aihara H, Yokobori S, Maeda T, Onuki T, Oshio K, Komoribayashi N, Suzuki M, and Maehara T
- Abstract
Objective: Neurological deterioration after mild traumatic brain injury (TBI) has been recognized as a poor prognostic factor. Early detection of neurological deterioration would allow appropriate monitoring and timely therapeutic interventions to improve patient outcomes. In this study, we developed a machine learning model to predict the occurrence of neurological deterioration after mild TBI using information obtained on admission., Methods: This was a retrospective cohort study of data from the Think FAST registry, a multicenter prospective observational study of elderly TBI patients in Japan. Patients with an admission Glasgow Coma Scale (GCS) score of 12 or below or who underwent surgical treatment immediately upon admission were excluded. Neurological deterioration was defined as a decrease of 2 or more points from a GCS score of 13 or more within 24 h of hospital admission. The model predictive accuracy was judged with the area under the receiver operating characteristic curve (AUROC) and the area under the precision-recall curve (AUPRC), and the Youden index was used to determine the cutoff value., Results: A total of 421 of 721 patients registered in the Think FAST registry between December 2019 and May 2021 were included in our study, among whom 25 demonstrated neurological deterioration. Among several machine learning algorithms, eXtreme Gradient Boosting (XGBoost) demonstrated the highest predictive accuracy in cross-validation, with an AUROC of 0.81 (±0.07) and an AUPRC of 0.33 (±0.08). Through SHapley Additive exPlanations (SHAP) analysis, five important features (D-dimer, fibrinogen, acute subdural hematoma thickness, cerebral contusion size, and systolic blood pressure) were identified and used to construct a better performing model (cross-validation AUROC of 0.84 and AUPRC of 0.34; testing data AUROC of 0.77 and AUPRC of 0.19). At the cutoff value from the Youden index, the model showed a sensitivity, specificity, and positive predictive value of 60, 96, and 38%, respectively. When neurosurgeons attempted to predict neurological deterioration using the same testing data, their values were 20, 94, and 19%, respectively., Conclusion: In this study, our predictive model showed an acceptable performance in detecting neurological deterioration after mild TBI. Further validation through prospective studies is necessary to confirm these results., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2025 Abe, Inaji, Hase, Suehiro, Shiomi, Yatsushige, Hirota, Hasegawa, Karibe, Miyata, Kawakita, Haji, Aihara, Yokobori, Maeda, Onuki, Oshio, Komoribayashi, Suzuki and Maehara.)
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- 2025
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8. Evaluation of Renal Perfusion: A Comparative Study between Intravoxel Incoherent Motion (IVIM) Imaging and Arterial Spin Labeling (ASL) to Assess Renal Blood Flow in Rodents.
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Ishimatsu K, Kikuchi K, Moe OW, Oshio K, Ishigami K, and Takahashi M
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Purpose: To compare diagnostic reliability between an intravoxel incoherent motion (IVIM) imaging and an arterial spin labeling (ASL) in assessment of renal blood flow in rodents., Methods: We first evaluated 3 different fitting methods on 5 datasets of diffusion-weighted imaging (DWI) with 10 b-values (0-1000 s/mm
2 ) for bi-exponential analysis in IVIM imaging to calculate pseudo-diffusion parameters. Coefficient of variation (CV) for each parameter and correlation among the parameters was assessed to test the robustness of the 3 fitting methods. Subsequently, DWI and ASL methods were performed before and 14 days after onset of acute kidney injury (AKI) in a rat model. Temporal change before and after AKI onset in the pseudo-diffusion parameters in 3 fitting methods was compared with that in the renal blood flow (RBF) derived in the ASL method., Results: The CVs in all IVIM parameters were the lowest in the fitting method that estimated pseudo-diffusion parameters after a fixed true-diffusion was determined where the pseudo- and true-diffusion coefficients had no correlation. The RBF substantially reduced (~50%, P < 0.001) due to the AKI onset; however, no pseudo-diffusion parameters in any of 3 fitting methods could not detect the change. Further, any pseudo-diffusion parameters showed no correlation with the RBF., Conclusion: Pseudo-diffusion parameters in the IVIM concept were not reliable to estimate RBF in the study. Since the kidney has a unique profile in the "tissue flow", our data indicate that study design and interpretation of results needs to be carefully considered when IVIM imaging is used for evaluation of blood flow in tissue, especially in the kidney.- Published
- 2024
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9. Characterizing Protein Concentration in Cerebrospinal Fluid with T 2 Component Analysis.
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Koizumi T, Shimizu S, Akiba C, Kakizoe H, Bandai H, Sato K, Nagasawa H, Ogino I, Nakajima M, Yamada S, Oshio K, and Miyajima M
- Abstract
Purpose: T
2 values are hypothesized to be reduced where protein accumulates in the cerebrospinal fluid (CSF). We aimed to verify the accuracy of Carr-Purcell-Meiboom-Gil (CPMG) pulses and non-negative least squares (NNLS) analysis in visualizing protein concentrations by mapping the T2 values., Methods: We first dissolved 1.2g of bovine serum albumin powder in 4 mL of artificial CSF to purify an albumin solution with a concentration of 4.5 mM. Artificial CSF was added thereto, and eight types of albumin solutions, with concentrations of 0.002-4.5 mM, were purified. We acquired this albumin solution with CPMG pulses and NNLS, decomposed the T2 values per pixel, and derived 25 T2 component values of 60-2000 ms. We assessed the change of T2 values by the difference in albumin concentration of a single voxel. Finally, we used the method to assess T2 values from two patients, one with a subdural hematoma and one with a suprasellar cystic tumor. T2 component values were plotted graphically, presented individually, and created in color maps., Results: T2 component values for albumin concentrations ranging from 0.056 to 4.55 mM showed different T2 peaks, whereas, for concentrations 0.002 to 0.019 mM, the peaks were similar heights and overlapped. Peak width was similar for all concentrations. The color maps successfully reflected the changes in T2 values across both RGB color patterns. T2 components for albumin samples with 2.5 mM and 6.1 mM concentrations within a single voxel were represented separately and reflected the ratio of the two samples in nine different regions of interest within one slice. In the clinical cases, the T2 component map imaged differences in albumin concentrations, similar to those observed in the albumin samples., Conclusion: The present method with CPMG sequences and NNLS provide adequate images to differentiate accumulating protein concentrations in the CSF, even at the level of a single pixel.- Published
- 2024
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10. Visualization of Cerebrospinal Fluid Outflow and Egress along the Nerve Roots of the Lumbar Spine.
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Vucevic D, Malis V, Bae WC, Ota H, Oshio K, McDonald MA, and Miyazaki M
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Intrinsic cerebrospinal fluid (CSF) dynamics in the brain have been extensively studied, particularly the egress sites of tagged intrinsic CSF in the meninges. Although spinal CSF recirculates within the central nervous system (CNS), we hypothesized that CSF outflows from the lumbar spinal canal. We aimed to visualize and semi-quantify the outflow using non-contrast MRI techniques. We utilized a 3 Tesla clinical MRI with a 16-channel spine coil, employing time-spatial labeling inversion (Time-SLIP) with tag-on and tag-off acquisitions, T2-weighted coronal 2D fluid-attenuated inversion recovery (FLAIR) and T2-weighted coronal 3D centric k
y -kz single-shot FSE (cSSFSE). Images were acquired using time-spatial labeling inversion pulse (Time-SLIP) with tag-on and tag-off acquisitions with varying TI periods. Ten healthy volunteers with no known spinal diseases participated. Variations in tagged CSF outflow were observed across different thoracolumbar nerve root segments in all participants. We quantified CSF outflow at all lumbar levels and the psoas region. There was no significant difference among the ROIs for signal intensity. The tagged CSF outflow from the spinal canal is small but demonstrates egress to surrounding tissues. This finding may pave the way for exploring intrathecal drug delivery, understanding of CSF-related pathologies and its potential as a biomarker for peripheral neuropathy and radiculopathy.- Published
- 2024
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11. Clinical meaning of sarcopenia in patients undergoing endoscopic treatment.
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Hisada H, Tsuji Y, Kuribara H, Miyata R, Oshio K, Mizutani S, Nakagawa H, Cho R, Sakuma N, Miura Y, Mizutani H, Ohki D, Yakabi S, Takahashi Y, Sakaguchi Y, Kakushima N, Yamamichi N, and Fujishiro M
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With increasing global life expectancy, the significance of geriatric assessment parameters has increased. Sarcopenia is a crucial assessment parameter and is defined as the age-related loss of muscle mass and strength. Sarcopenia is widely acknowledged as a risk factor for postoperative complications in diverse advanced malignancies and has a detrimental effect on the long-term prognosis. While most studies have primarily concentrated on the correlation between sarcopenia and advanced cancer, more recent investigations have focused on the relationship between sarcopenia and early-stage cancer. Endoscopic submucosal dissection (ESD), which is less invasive than surgical intervention, is extensively employed in the management of early-stage cancer, although it is associated with complications such as bleeding and perforation. In recent years, several reports have revealed the adverse consequences of sarcopenia in patients with early-stage cancer undergoing ESD. This literature review briefly summarizes the recent studies on the association between sarcopenia and ESD.
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- 2024
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12. Verification of the increase in concomitant dysplasia and cancer with the size of sessile serrated lesions.
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Ohki D, Tsuji Y, Hisada H, Nakagawa H, Mizutani S, Oshio K, Sato J, Kubota D, Cho R, Miura Y, Mizutani H, Sakaguchi Y, Takahashi Y, Yakabi S, Kakushima N, Yamamichi N, Ushiku T, and Fujishiro M
- Abstract
Background and study aims This study aimed to evaluate the relationship between sessile serrated lesion (SSL) size and the comorbidity rate of SSL with dysplasia (SSLD) and cancer in SSL (SSL-cancer). Patients and methods This retrospective, single-center analysis identified SSL cases that underwent endoscopic resection between January 2015 and December 2022. The prevalence of SSL, SSLD, and SSL-cancer and their annual trends were assessed. The tumor diameter was stratified as 0 to 5 mm, 6 to 9 mm, 10 to 19 mm, and ≥ 20 mm in size. Furthermore, the frequency of SSL-D/SSL-cancer was determined in each group. Results The prevalence of SSL was 2.9% (1328/45799). This prevalence was 1.8% (112/6192) in 2015 and 4.2% (230/5500) in 2022, indicating an increasing trend over time. A total of 1825 lesions were assessed: 1751 (96.0%), 55 (3.0%), 14 (0.8%), and 5 (0.3%) of lesions were SSL, SSL with low-grade dysplasia, SSL with high-grade dysplasia and SSL-cancer, respectively. Stratifying the SSLs by size: 0 to 5 mm, 5 to 9 mm, 10 to 19 mm, and ≥ 20 mm, SSLD and SSL-cancer rates were 2.3% (10/429), 2.4% (16/674), 5.3% (31/584), and 11.8% (16/136), respectively. SSLD and SSL-cancer were observed in 2.4% (26/1103) of small SSLs < 10 mm. Conclusions In cases of SSL, the rate of SSLD and SSL-cancer increased as the lesion diameter increased. A certain rate of SSLD and SSL-cancer was observed even in small SSLs less than 5mm., Competing Interests: Conflict of Interest The authors declare that they have no conflict of interest., (The Author(s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution-NonDerivative-NonCommercial-License, permitting copying and reproduction so long as the original work is given appropriate credit. Contents may not be used for commercial purposes, or adapted, remixed, transformed or built upon. (https://creativecommons.org/licenses/by-nc-nd/4.0/).)
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- 2024
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13. The current status of reversal therapy in Japan for elderly patients with head injury treated with antithrombotic agents: A prospective multicenter observational study.
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Suehiro E, Shiomi N, Yatsushige H, Hirota S, Hasegawa S, Karibe H, Miyata A, Kawakita K, Haji K, Aihara H, Yokobori S, Inaji M, Maeda T, Onuki T, Oshio K, Komoribayashi N, and Suzuki M
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Background: Acute exacerbation of head injury in elderly patients due to use of antithrombotic agents has become a concern in countries with aging populations. Reversal agents are recommended for treatment, but its usage is unclear. Therefore, we conducted a prospective observational study in this patient population to monitor usage of reversal therapy., Methods: The subjects were 721 elderly patients aged ≥65 years old who were hospitalized in 15 centers from December 2019 to May 2021. Patients were divided into groups who did not receive antithrombotic agents (Group A), who received antithrombotic agents, but did not receive reversal therapy (Group B), and were treated with antithrombotic agents and reversal therapy (Group C). Age, gender, mechanism of injury, neurologic and imaging findings on admission, clinical course after admission and surgery, outcomes and complications were compared among these groups. Time from injury to reversal therapy was examined based on outcomes to investigate trends in the timing of administration of the reversal agent., Results: Acute exacerbation during the clinical course occurred in 9.8 %, 15.8 % and 31.0 % of cases in Groups A, B and C, respectively, and differed significantly among the groups. On head CT, the incidences of hematoma were 35.7 %, 36.5 % and 60.4 %, respectively, with this incidence being significantly higher in Group C; and the respective rates of craniotomy were 18.8 %, 14.0 % and 50.9 %, again with this rate being significantly higher in Group C. The good outcome and mortality rates were 57.1 %, 52.5 % and 35.8 %, and 14.5 %, 18.0 % and 24.5 %, respectively, and both were poorest in Group C. Times from injury to treatment with a reversal agent were significantly shorter in patients without compared to those with acute exacerbation (405.9 vs. 880.8 min) and in patients with favorable outcomes compared to those with unfavorable outcomes (261.9 vs. 543.4 min)., Conclusion: Similarly to previous studies, the incidence of acute exacerbation was increased by use of antithrombotic agents. These results suggest that patients in Japan who require hematoma evacuation due to symptom exacerbation tend to be treated with reversal agents. Although it is difficult to assess the efficacy of reversal therapy from this study, earlier treatment with reversal agents before the occurrence of acute exacerbation may be useful to improve outcomes., Competing Interests: The authors declare the following financial interests/personal relationships which may be considered as potential competing interests. Eiichi Suehiro reports financial support was provided by 10.13039/100008322CSL Behring K.K. United States. Eiichi Suehiro reports a relationship with Boehringer Ingelheim, Germany that includes: funding grants. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)
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- 2024
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14. Retrospective Observational Study of Patients With Subdural Hematoma Treated With Idarucizumab.
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Suehiro E, Ishihara H, Kogeichi Y, Ozawa T, Haraguchi K, Honda M, Honda Y, Inaba M, Kabeya R, Kanda N, Koketsu K, Murakami N, Nakamoto H, Oshio K, Saigusa K, Shuto T, Sugiyama S, Suzuyama K, Terashima T, Tsuura M, Nakada M, Kobata H, Higashi T, Sakai N, and Suzuki M
- Abstract
Use of anticoagulants is increasing with the aging of societies. The safe first-line drug is likely to be a direct oral anticoagulant (DOAC), but outcomes of treatment of traumatic brain injury (TBI) with anticoagulants are uncertain. Therefore, we examined the clinical effect of idarucizumab as reversal therapy in elderly patients with TBI who were treated with dabigatran. A retrospective multi-center observational study was performed in patients ≥65 years of age who developed acute traumatic subdural hematoma during treatment with dabigatran and underwent reversal therapy with idarucizumab. The items examined included patient background, neurological and imaging findings at arrival, course after admission, complications, and outcomes. A total of 23 patients were enrolled in the study. The patients had a mean age of 78.9 years. Cause of TBI was fall in 60.9% of the subjects. Mean Glasgow Coma Scale score at arrival was 8.7; anisocoria was present in 31.8% of cases. Exacerbation of consciousness was found in 30.4%, but only in 13.3% of subjects treated with idarucizumab before consciousness and imaging findings worsened. Dabigatran was discontinued in 81.8% of cases after hematoma development, with a mean withdrawal period of 12.1 days. The favorable outcome rate was 21.7%, and mortality was 39.1%. In multi-variate analysis, timing of idarucizumab administration was associated with a favorable outcome. There were ischemic complications in 3 cases (13.1%), and all three events occurred ≥7 days after administration of idarucizumab. These findings suggest that in cases that develop hematoma during treatment with dabigatran, it is important to administer idarucizumab early and restart dabigatran after conditions stabilize., Competing Interests: Dr. Suehiro received research funding from Boehringer Ingelheim., (© Eiichi Suehiro et al., 2023; Published by Mary Ann Liebert, Inc.)
- Published
- 2023
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15. Performing the ABC Method Twice for Gastric Cancer Risk Stratification: A Retrospective Study Based on Data from a Large-Scale Screening Facility.
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Mizutani S, Takahashi Y, Shimamoto T, Nakagawa H, Hisada H, Oshio K, Kubota D, Mizutani H, Ohki D, Sakaguchi Y, Yakabi S, Niimi K, Kakushima N, Tsuji Y, Wada R, Yamamichi N, and Fujishiro M
- Abstract
The ABC method is a classification method used for stratifying the risk of gastric cancer. However, whether the ABC method should be performed only once or multiple times throughout an individual's lifetime remains unclear. Therefore, this study aimed to analyze whether performing ABC screening twice in a lifetime is useful. We retrospectively analyzed the data of individuals who participated in health checkups in 2010 and 2015. We collected data on patient characteristics, pepsinogen levels, anti- Helicobacter pylori antibody titers, and the presence of gastric cancer. Overall, 7129 participants without a history of H. pylori eradication were included in this study. The participants' average age in 2010 was 48.4 ± 8.3 years, and 58.1% were male. In addition, 11 and 20 cases of new H. pylori infection (0.15%) and spontaneous eradication (0.28%), respectively, were recorded. No significant difference was found in the incidence of gastric cancer between participants who underwent the ABC method once and those who underwent it twice (Group A: 0.16% vs. 0.16%; Group B: 0.47% vs. 0.39%; and Group C + D: 1.97% vs. 1.82%). Therefore, performing the ABC method twice, 5 years apart, does not significantly improve gastric cancer risk stratification.
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- 2023
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16. What Is the "Glymphatic System"?
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Oshio K
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- Brain diagnostic imaging, Brain metabolism, Glymphatic System diagnostic imaging, Glymphatic System metabolism
- Abstract
Although the glymphatic system hypothesis is highly popular, it also lacks certain details. In this paper, an attempt was made to present a more clearly defined hypothesis, which is consistent with the past experiment results. The new hypothesis consists of (1) water flux in the brain parenchyma, (2) water and solutes pathway of the perivascular space, and (3) maintenance of this pathway by the network of astrocytes.
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- 2023
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17. Endoscopic Treatment of Superficial Gastric Cancer: Present Status and Future.
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Hisada H, Sakaguchi Y, Oshio K, Mizutani S, Nakagawa H, Sato J, Kubota D, Obata M, Cho R, Nagao S, Miura Y, Mizutani H, Ohki D, Yakabi S, Takahashi Y, Kakushima N, Tsuji Y, Yamamichi N, and Fujishiro M
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- Early Detection of Cancer, Gastric Mucosa pathology, Gastric Mucosa surgery, Gastroscopy, Humans, Endoscopic Mucosal Resection, Stomach Neoplasms pathology, Stomach Neoplasms surgery
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Although the mortality rates of gastric cancer (GC) are gradually declining, gastric cancer is still the fourth leading cause of cancer-related death worldwide. This may be due to the high rate of patients who are diagnosed with GC at advanced stages. However, in countries such as Japan with endoscopic screening systems, more than half of GCs are discovered at an early stage, enabling endoscopic resection (ER). Especially after the introduction of endoscopic submucosal dissection (ESD) in Japan around 2000, a high en bloc resection rate allowing pathological assessment of margin and depth has become possible. While ER is a diagnostic method of treatment and may not always be curative, it is widely accepted as standard treatment because it is less invasive than surgery and can provide an accurate diagnosis for deciding whether additional surgery is necessary. The curability of ER is currently assessed by the completeness of primary tumor removal and the possibility of lymph node metastasis. This review introduces methods, indications, and curability criteria for ER of EGC. Despite recent advances, several problems remain unsolved. This review will also outline the latest evidence concerning future issues.
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- 2022
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18. Blood Glucose Response of a Low-Carbohydrate Oral Nutritional Supplement with Isomaltulose and Soluble Dietary Fiber in Individuals with Prediabetes: A Randomized, Single-Blind Crossover Trial.
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Kokubo E, Morita S, Nagashima H, Oshio K, Iwamoto H, and Miyaji K
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- Cross-Over Studies, Dietary Fiber, Glucose, Humans, Insulin, Isomaltose analogs & derivatives, Postprandial Period, Single-Blind Method, Blood Glucose, Prediabetic State
- Abstract
A high-energy-type oral dietary supplement (ONS), with a low proportion of available carbohydrate (LC-ONS), which contains a slowly digestible carbohydrate, isomaltulose, and is fortified with soluble dietary fiber, was newly developed for individuals with diabetes or prediabetes. This study aimed to evaluate the impact of LC-ONS on blood glucose levels after ingestion in individuals with prediabetes. A single-blind, randomized crossover clinical trial was performed on 20 individuals with prediabetes. After overnight fasting, all subjects ingested one serving (200 kcal/125 mL) of either LC-ONS (40% energy proportion of available carbohydrates) or standard ONS (ST-ONS, 54% energy proportion of available carbohydrates) on two separate days. The incremental area under the curve of blood glucose levels for 120 min was significantly lower after LC-ONS ingestion compared to ST-ONS (2207 ± 391 mg/dL·min (least mean square value ± standard error) and 3735 ± 391 mg/dL·min, respectively; p < 0.001). The LC-ONS showed significantly lower blood glucose levels than the ST-ONS at all time points, except at baseline. Similarly, the incremental area under the curve of plasma insulin was significantly lower after LC-ONS ingestion. These results suggest that LC-ONS is useful as an ONS for energy supply in individuals with postprandial hyperglycemia.
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- 2022
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19. Analysis of relationship between loading condition and cranial cracking pattern using a three-dimensional finite element model.
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Kiriyama Y, Sato Y, Muramatsu Y, Mano T, Tanaka K, and Oshio K
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- Accidental Falls, Finite Element Analysis, Humans, Fractures, Bone, Skull diagnostic imaging
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Background: A hairline crack on the cranium can occur even under a small external load or impact and are thus often observed in patients who have experienced an accidental fall or collision. Typical finite element analysis is useful to analyze the stress concentration or the propagation of stress waves. However, a stress propagation model does not accurately reproduce the features of hairline cracks on the cranium. The objective in this study was to reproduce cranial hairline cracks., Methods: A three-dimensional finite element model of the cranial bone was developed from a patient CT images. The model consists of the frontal, parietal, occipital and temporal bones, and the bones are connected with the sutures. Additionally, the model comprised three layers; the external and internal tables and the diploe. The model was analyzed using the extended finite element method (X-FEM), and a forming limit diagram (FLD) was embedded in the model. In this study, the model was symmetrized bilaterally using the model developed from the left side of the skull. The FLD in this study was assumed to be a relationship between the maximum and minimum strains when a fracture occurs. A total of 13 typical loadings were applied to the model: loading points on the top, left, and back of the cranium were considered, and at each loading point, loads were applied with four or five different directions, namely perpendicular to the cranium and inclined in the anterior, posterior, superior, or inferior at an angle of 45
∘ ., Results: Under all loading conditions, many small cracks formed radially at the loading points. Moreover, some large cracks formed under the certain loading conditions. The crack shapes on the top and left side could be associated with the specific loading directions, whereas cracks on the back did not show distinguishing characteristics depending on the loading directions. The present model was reproduced anatomically and morphologically, and the results were similar to those obtained in previous cadaver experiments., Conclusions: Through X-FEM analysis of the FE model embedded with an FLD, hairline cracks in the cranium were reproduced, and a few crack shapes were identified as potential markers for estimating the loading conditions., (© 2022. The Author(s).)- Published
- 2022
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20. The Spatial Distribution of Water Components with Similar T 2 May Provide Insight into Pathways for Large Molecule Transportation in the Brain.
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Oshio K, Yui M, Shimizu S, and Yamada S
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- Cerebrospinal Fluid diagnostic imaging, Cerebrospinal Fluid metabolism, Extracellular Space diagnostic imaging, Extracellular Space metabolism, Humans, Biological Transport physiology, Body Water diagnostic imaging, Body Water metabolism, Brain diagnostic imaging, Brain metabolism, Magnetic Resonance Imaging methods
- Abstract
Purpose: Although there is no lymphatic system in the central nervous system (CNS), there seems to be a mechanism to remove macro molecules from the brain. Cerebrospinal fluid (CSF) and interstitial fluid (ISF) are thought to be parts of this pathway, but the details are not known. In this study, MR signal of the extracellular water was decomposed into components with distinct T
2 's, to obtain some information about distribution of waste material in the brain., Methods: Images were acquired using a Curr, Purcell, Meiboom, Gill (CPMG) imaging sequence. In order to reduce T1 contamination and the signal oscillation, hard pulses were used as refocusing pulses. The signal was then decomposed into many T2 components using non-negative least squares (NNLS) in pixel-by-pixel basis. Finally, a color map was generated by assigning different color for each T2 component, then adding them together., Results: From the multi-echo images, it was possible to decompose the decaying signal into separate T2 components. By adjusting the color table to create the color map, it is possible to visualize the extracellular water distribution, as well as their T2 values. Several observation points include: (1) CSF inside ventricles has very long T2 (~2 s), and seems to be relatively homogeneous, (2) subarachnoid CSF also have long T2 , but there are short T2 component at the brain surface, at the surface of dura, at the blood vessels in the subarachnoid space, etc., (3) in the brain parenchyma, short T2 components (longer than intracellular component but shorter than CSF) exists along the white matter, in the choroid plexus, etc. These can be considered as distribution of macromolecules (waste materials) in the brain., Conclusion: From T2 component analysis it is possible to obtain some insight into pathways for the transport of large molecules in the CNS, where no lymphatic system is present.- Published
- 2021
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21. A case of tandem stenoses at the proximal common and internal carotid arteries treated with transbrachial stenting: a case report.
- Author
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Ito H, Uchida M, Sase T, Kushiro Y, Ikeda T, Takasuna H, Takumi I, Oshio K, and Tanaka Y
- Subjects
- Angiography, Digital Subtraction, Carotid Artery, Common, Carotid Artery, Internal, Carotid Stenosis diagnostic imaging, Computed Tomography Angiography, Humans, Male, Middle Aged, Platelet Aggregation Inhibitors therapeutic use, Tomography, X-Ray Computed, Ultrasonography, Carotid Stenosis surgery, Stents
- Abstract
The transfemoral approach is a common technique for carotid artery stenting. However, it has the risk of distal embolism when stenting for a stenosis of the proximal common carotid artery because of poor stability of the guiding catheter resulting in difficulty in setting the embolic protection device prior to stenting. We present a novel therapeutic approach and technique for the treatment of tandem carotid stenoses including the proximal common carotid artery. A 63-year-old man presented with double stenoses at the common carotid artery and internal carotid artery. We used a transbrachial sheath guide that had a 6 Fr (2.24 mm, 0.088 inch) internal diameter and was 90 cm long, and was specifically designed for direct cannulation to the common carotid artery, like a modified Simmons catheter. Because the sheath guide positioned in the aortic arch made it possible to introduce safely the embolic protection device distal to the internal carotid artery stenosis without touching the plaque at the stenosis with no use of any coaxial catheters or guidewires, carotid artery stenting for tandem stenoses could be successfully carried out. The postoperative course was uneventful. In carotid artery stenting, especially for stenosis of the proximal common carotid artery, the sheath guide designed for transbrachial carotid cannulation was useful in stenting the tandem carotid stenoses.
- Published
- 2019
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22. Risk Factors of Contralateral Microembolic Infarctions Related to Carotid Artery Stenting.
- Author
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Ito H, Uchida M, Sase T, Kushiro Y, Wakui D, Onodera H, Takasuna H, Morishima H, Oshio K, and Tanaka Y
- Subjects
- Aged, Aged, 80 and over, Brain Infarction diagnostic imaging, Carotid Stenosis complications, Diffusion Magnetic Resonance Imaging, Female, Humans, Intracranial Embolism diagnostic imaging, Male, Middle Aged, Retrospective Studies, Risk Factors, Angioplasty adverse effects, Brain Infarction etiology, Carotid Stenosis surgery, Intracranial Embolism etiology, Stents adverse effects
- Abstract
This study sought to analyze the incidence of contralateral microembolic infarctions (MIs) on diffusion-weighted imaging (DWI) following protected carotid artery stenting (CAS) and compared the difference of risk factors between ipsilateral and contralateral lesions. From April 2010 to March 2017, 147 CASs in 140 patients were performed. All the patients underwent DWI within 1 week before and 24 hrs after the procedures. CAS was successfully completed in 145 (98.6%) of the 147 procedures. Forty-nine (33.8%) patients with new MIs revealed on postprocedural DWI were enrolled. They were divided into ipsilateral and contralateral groups based on the side of the CAS and MIs. The ipsilateral group indicates patients with MIs exclusively on the side of CAS. The contralateral group includes patients with MIs on the opposite side of the CAS or both sides. Patients with MIs at vertebrobasilar territory were excluded. Patient characteristics, morphology of the carotid artery and aortic arch, and procedural data were retrospectively assessed and compared between the two groups. Twenty-two (15.2%) and 14 (9.7%) patients were assigned to the ipsilateral and contralateral groups, respectively. Advanced age, left-sided stenosis, severe aortic arch calcification (AAC) on chest X-ray and contralateral carotid occlusion significantly increased the occurrence of contralateral MIs. On multivariable logistic regression analysis, severe AAC was statistically more frequent in the contralateral group. In the present study, the incidences of contralateral MIs after CAS is relatively not low. Advanced aortic atherosclerosis is statistically predictive for contralateral MIs. AAC on chest X-ray is a useful finding for estimating aortic atherosclerosis in candidates for CAS.
- Published
- 2018
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23. Surgical removal of an arteriovenous malformation in the anterior perforated substance in a pregnant woman.
- Author
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Wakui D, Ito H, Takasuna H, Onodera H, Oshio K, and Tanaka Y
- Abstract
Background: A tailor-made treatment is often required in arteriovenous malformations (AVMs) depending on the individual situation. In most cases, treatment strategy is usually determined according to the patient's Spetzler-Martin grade. However, in the present case, we were not able to treat the patient following the usual guidelines because of neurological symptoms and pregnancy., Case Description: We describe a rare case of a 31-year-old woman in the 15
th week of gestation who presented with an AVM in the anterior perforated substance (APS). She suffered a sudden coma and hemiplegia. A computed tomographic scan showed an enhanced mass and a huge hematoma in the basal ganglia and temporal lobe. The hematoma was successfully evacuated in an endoscopic procedure. Angiography showed that a 25-mm nidus in the APS was fed by the anterior choroidal arteries (AChAs) and the lenticulostriate arteries (LSAs). Therefore, we attempted to remove the nidus because the patient became alert with mild aphasia and hemiparesis 10 days after hemorrhage. The feeding arteries were cut under motor evoked potential (MEP) monitoring, and the nidus was totally resected leaving two of four AChAs and a single artery with several LSAs. The postoperative course was uneventful, and she gave birth to a healthy baby by caesarian delivery 122 days after the hemorrhage with only minor sequelae., Conclusions: Surgical strategy with a device-administered anesthesia are suitable for removing large AVMs even in pregnant women and for the successful outcome of their pregnancies. Even after recovering from a coma and hemiplegia, MEP monitoring is effective for removing large AVMs even when located in the APS., Competing Interests: There are no conflicts of interest.- Published
- 2018
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24. Quantification of edematous changes by diffusion magnetic resonance imaging in gastrocnemius muscles after spinal nerve ligation.
- Author
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Abe K, Nakamura T, Yamabe E, Oshio K, Miyamoto T, Nakamura M, Matsumoto M, and Sato K
- Subjects
- Animals, Female, Ligation, Neovascularization, Pathologic diagnostic imaging, Neovascularization, Pathologic metabolism, Neovascularization, Pathologic physiopathology, Rats, Rats, Wistar, Vascular Endothelial Growth Factor A metabolism, Magnetic Resonance Imaging, Muscle, Skeletal blood supply, Muscle, Skeletal diagnostic imaging, Muscle, Skeletal innervation, Muscle, Skeletal metabolism, Neuralgia diagnostic imaging, Neuralgia metabolism, Neuralgia pathology, Neuralgia physiopathology, Spinal Nerves diagnostic imaging, Spinal Nerves injuries, Spinal Nerves metabolism, Spinal Nerves physiopathology
- Abstract
Patients with complex regional pain syndrome (CRPS) exhibit diverse symptoms, such as neuropathic pain, allodynia, local edema and skin color changes in the affected lesion. Although nerve injury may cause CRPS, pathophysiological mechanisms underlying the syndrome are unclear, and local edema, a characteristic of CRPS, has not been evaluated quantitatively for technical reasons. Here, using a rat spinal nerve ligation-induced CRPS model, we show that edematous changes in gastrocnemius muscle can be detected quantitatively by diffusion magnetic resonance imaging (MRI). Using the line-scan diffusion spectrum on a 1.5 T clinical MR imager, we demonstrate significant elevation of the apparent diffusion coefficient (ADC) ratios in gastrocnemius muscle on the ligated versus the sham-operated rats by one day after surgery, those ratios gradually decreased over time. Meanwhile, T2 ratios in gastrocnemius muscle on the ligated rats increased gradually and significantly, peaking two weeks after surgery, and those ratios remained high and were consistent with edema. Expression of vascular endothelial growth factor (VEGF), a key regulator of blood vessel formation and function, was significantly lower in gastrocnemius muscle on the ligated versus non-ligated side, suggesting that nerve ligation promotes edematous changes and perturbs VEGF expression in target muscle.
- Published
- 2018
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25. Clinical significance of thickened sphenoid sinus mucosa in Rathke's cleft cyst.
- Author
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Takasuna H, Sase T, Ito H, Ono H, Oshio K, and Tanaka Y
- Abstract
Background: To determine the clinical significance of thickening of the sphenoid sinus mucosa (TSSM) in Rathke's cleft cyst (RCC)., Methods: We retrospectively reviewed patients with pituitary lesions. A total of 99 patients, who underwent surgery of pituitary lesions between 2008 and 2015, were analyzed to evaluate the clinical significance of TSSM using magnetic resonance imaging. The patients with TSSM were evaluated for their characteristics., Results: Of the 99 operations, 15 patients with paranasal sinusitis, direct invasion to the sellar floor, and/or a history of transsphenoidal surgery were excluded. There were 51 pituitary adenomas (PAs), 18 RCCs, and 15 other tumors. TSSM was observed in 6 patients (7.1%). Pathologies included 3 RCCs (16.7%), 1 PA (2.0%), and 2 other lesions. Three RCCs were especially analyzed. The pituitary dysfunction was found in all 3 patients with TSSM, whereas that was noted in 2 of 15 patients (13.3%) without TSSM. The sensitivity was 60%, specificity was 86.7%, and the positive predictive value was 100%. There was no significant difference in the age, thickness of TSSM, symptoms, and squamous metaplasia between patients with and without TSSM., Conclusions: TSSM occurs more frequently in RCCs than in PAs. TSSM can potentially suggest hypopituitarism in RCCs. The surgical and/or endocrinological interventions are required for preventing further endocrine deterioration., Competing Interests: There are no conflicts of interest.
- Published
- 2017
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26. Outflow occlusion with A3-A3 anastomosis for a doughnut-shaped partially thrombosed giant A2 aneurysm.
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Ito H, Miyano R, Sase T, Wakui D, Matsumori T, Takasuna H, Oshio K, and Tanaka Y
- Abstract
Background: A doughnut-shaped aneurysm, which is defined as a round-shaped aneurysm composed of an intraluminar thrombus and marginal parent artery, is an extremely uncommon subtype of partially thrombosed giant aneurysms. Surgical treatment of this characteristic aneurysm is technically challenging., Case Description: We report a rare case of a 79-year-old man with a symptomatic doughnut-shaped giant aneurysm at the A2 portion, which was successfully treated by outflow occlusion with an A3-A3 side-to-side anastomosis. Postoperative angiograms demonstrated no filling of the doughnut-shaped aneurysm and perfusion in the distal right anterior cerebral artery territory via the anastomosis. Follow-up magnetic resonance imaging 1 year after the surgery demonstrated significant diminution of the aneurysm., Conclusions: Outflow occlusion with distal revascularization could be an effective surgical option for such a unique aneurysm. To the best of our knowledge, this is the first report of outflow occlusion as a therapy for doughnut-shaped aneurysms., Competing Interests: There are no conflicts of interest.
- Published
- 2016
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27. Steroid-resistant Tolosa-Hunt syndrome with a de novo intracavernous aneurysm: A case report.
- Author
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Takasuna H, Sasaki R, Shiraishi M, Doi M, Wakui D, Ito H, Oshio K, and Tanaka Y
- Abstract
Background: We report a case of steroid-resistant Tolosa-Hunt syndrome (THS) with recurrent bilateral painful ophthalmoplegia, accompanied with sphenoid sinusitis, pituitary abscess, and an aneurysm arising from the cavernous portion of the internal carotid artery., Case Description: A 53-year-old woman suffered severe left painful ophthalmoplegia. A magnetic resonance image (MRI) revealed thickness of the left cavernous sinus (CS). Steroid was administrated under the diagnosis of THS, and the symptom transiently diminished. However, painful ophthalmoplegia fluctuated bilaterally after tapering the steroid. An MRI showed development of bilateral cavernous lesions associated with sphenoid sinusitis, pituitary abscess, and an aneurysm in the left C4 segment. Biopsy and drainage of the lesions were performed with an endoscopic transsphenoidal procedure. The histological examination showed nonspecific granulomatous inflammation. The methotrexate (MTX) was effective to reduce the CS and pituitary lesions; however, the aneurysm slightly increased and remained unchanged in size thereafter., Conclusions: To our knowledge, this is the first report of a growing de novo C4 aneurysm in THS. Surgical intervention and administration of MTX should be attempted in steroid-resistant THS. Careful observation with serial MRI and MR angiography is important to manage the complicated THS.
- Published
- 2016
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28. Ruptured dermoid cyst of the lateral cavernous sinus wall with temporary symptoms: a case report.
- Author
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Kosuge Y, Onodera H, Sase T, Uchida M, Takasuna H, Ito H, Oshio K, and Tanaka Y
- Subjects
- Aged, Humans, Magnetic Resonance Imaging, Male, Rupture, Spontaneous, Brain Neoplasms diagnostic imaging, Cavernous Sinus diagnostic imaging, Dermoid Cyst diagnostic imaging
- Abstract
Background: Dermoid cysts are non-neoplastic tumors that arise from defects in the separation of the neuroectoderm. Cyst rupture rarely occurs spontaneously and the most common symptom is headache, followed by seizure. Although many cases of ruptured dermoid cysts present with symptoms, reports of cases that are asymptomatic, or where symptoms disappear, are rare., Case Presentation: We report the case of a 66-year-old Asian man with a history of sudden onset headache who was found to have high amounts of fat material in the subarachnoid space and a fat suppression mass in the left cavernous sinus. He underwent oral steroid therapy. Five days after starting medication his headache symptoms disappeared. Routine neurological imaging was then performed without surgical procedure. Magnetic resonance imaging revealed evidence of the remains of a static lesion 6 months after his first visit. He has remained headache free for 10 months since the initial event., Conclusions: Although cases of ruptured dermoid cysts presenting with consistent symptoms have been commonly reported, until now there were few reports on asymptomatic cases or cases where symptoms disappeared. We believe that surgical intervention is unnecessary for ruptured dermoid cysts with minimal symptoms.
- Published
- 2016
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29. Dietary supplementation with shiikuwasha extract attenuates dexamethasone-induced skeletal muscle atrophy in aged rats.
- Author
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Sakata Y, Okamoto T, Oshio K, Nakamura H, Iwamoto H, Namba K, Takeda Y, and Yoshizawa F
- Abstract
Background: Skeletal muscle atrophy is caused by a variety of diseases and conditions. In particular, skeletal muscle atrophy in the elderly contributes to a loss of independence with advanced age and increases the risk of falling. However, the effect of food consumed on a daily basis on skeletal muscle atrophy has been the focus of little research. In this study, the effects of dietary supplementation with shiikuwasha extract or grape extract on dexamethasone-induced skeletal muscle atrophy were evaluated in aged rats., Methods: Aged male rats (15-month-old) were fed a diet supplemented with either 1 % shiikuwasha extract or 1 % grape extract for 19 days. During the last 5 days of the feeding period, rats were injected with dexamethasone to induce muscle atrophy., Results: Body weight and hind-limb muscle weight were significantly decreased by dexamethasone treatment. The supplementation of shiikuwasha extract showed no effect on body weight loss, but markedly attenuated tibialis anterior muscle weight loss induced by dexamethasone. On the other hand, grape extract did not affect muscle weight loss. Furthermore, shiikuwasha extract significantly reduced dexamethasone-induced expression of atrogin-1 and MuRF1 mRNA, but did not reduce LC3B-II protein levels., Conclusion: These results suggest that shiikuwasha extract may partially inhibit the activation of the ubiquitin-proteasome system and may consequently attenuate skeletal muscle atrophy induced by dexamethasone in aged rats.
- Published
- 2016
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30. Impact of Aneurysmal Neck Position in Endovascular Therapy for Anterior Communicating Artery Aneurysms.
- Author
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Ito H, Onodera H, Wakui D, Uchida M, Sase T, Morishima H, Oshio K, and Tanaka Y
- Subjects
- Adult, Aged, Aged, 80 and over, Aneurysm, Ruptured therapy, Angiography, Endovascular Procedures, Female, Humans, Imaging, Three-Dimensional, Male, Middle Aged, Retrospective Studies, Treatment Outcome, Anterior Cerebral Artery diagnostic imaging, Embolization, Therapeutic, Intracranial Aneurysm therapy
- Abstract
Anterior communicating artery (ACoA) aneurysms have a complex architecture and many variations, making endovascular therapy more difficult in some cases. The aim of this study was to investigate whether the neck position of an aneurysm was identifiable for determining the immediate angiographic success and procedural complications in the coiling of the ACoA aneurysms. We conducted a retrospective case review of 40 patients with ACoA aneurysms treated by endovascular therapy from 2008 to 2015. The mean age was 66.8 years. Thirty-five aneurysms were ruptured; five were unruptured. For the analysis, the patients were divided into two groups according to the neck position of aneurysms: the true ACoA group, 9 patients with the neck located on the ACoA itself; and the other ACoA group, 31 patients with the neck at the junction of the A1 and A2 portions of an anterior cerebral artery. Morphological characteristics (dome size, dome direction, rate of wide neck, and angulation of aneurysms in relation to the parent artery) were analyzed along with immediate angiographic results, volume embolization ratio (VER), and procedural complications. Small aneurysms with superior dome projection and acute angulation of the aneurysm direction occurred more often in the true ACoA group. The rates of complete obliteration, VER, and procedural complications were 33.3%, 32.3%, and 22.2% in the true ACoA group and 54.8%, 36.3%, and 6.5% in the other ACoA group, respectively. True ACoA aneurysms could present an anatomical difficulty in endovascular coiling. Aneurysmal neck position should be accurately assessed to achieve successful embolization of the ACoA aneurysms.
- Published
- 2016
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31. Diffusion-weighted MR Imaging for the Assessment of Renal Function: Analysis Using Statistical Models Based on Truncated Gaussian and Gamma Distributions.
- Author
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Yamada K, Shinmoto H, Oshio K, Ito S, Kumagai H, and Kaji T
- Subjects
- Adult, Aged, Aged, 80 and over, Female, Humans, Male, Middle Aged, Diffusion Magnetic Resonance Imaging methods, Kidney diagnostic imaging, Kidney physiology, Kidney Function Tests methods, Models, Statistical
- Abstract
Purpose: To determine the appropriateness of statistical models using the truncated Gaussian distribution and gamma distribution for diffusion signal decay, and to assess the correlation between the parameters obtained from the statistical models and estimated glomerular filtration rate (eGFR)., Methods: Twenty-nine patients with chronic kidney disease and 21 healthy volunteers were included and classified in four groups according to eGFR (ml/min/1.73 m(2)): group 1 (90 ≤ eGFR, n = 10), group 2 (eGFR 60-90, n = 15), group 3 (eGFR 30-60, n = 17), and group 4 (eGFR < 30, n = 8). Diffusion-weighted imaging using five b-values (0, 500, 1000, 1500, and 2000 s/mm(2)) was performed. Truncated Gaussian and gamma models were compared for goodness of fit. Area fractions for the diffusion coefficient D < 1.0 × 10(-3) mm(2)/s (Frac < 1.0) and D > 3.0 × 10(-3) mm(2)/s (Frac > 3.0) obtained from the statistical model were compared among four groups. Correlation between proposed parameters and conventional apparent diffusion coefficient (ADC) with eGFR was calculated., Results: There was no significant difference in goodness of fit between the truncated Gaussian and gamma models. Frac < 1.0 and Frac > 3.0 showed good correlation with eGFR, as did ADC. Comparison between groups 1 and 2 showed that only Frac < 1.0 in both distribution models had significant differences., Conclusion: Statistical models yield robust interpretation of diffusion magnetic resonance (MR) signals with relevance to histological changes in the kidney. The parameters of the statistical models, particularly Frac < 1.0, strongly correlated with eGFR.
- Published
- 2016
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32. Removing Ambiguity Caused by T2 Shine-through using Weighted Diffusion Subtraction (WDS).
- Author
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Oshio K, Okuda S, and Shinmoto H
- Subjects
- Algorithms, Humans, Subtraction Technique statistics & numerical data, Diffusion Magnetic Resonance Imaging statistics & numerical data, Image Processing, Computer-Assisted statistics & numerical data
- Abstract
We propose a novel image processing technique that combines images routinely acquired with low and high b values to create a single image that contains clinically useful information without the ambiguity of T2 shine-through. The contrast of resulting images is similar to that of a T2 image, but the signals of pixels with low apparent diffusion coefficient (ADC) values are inverted. The proposed technique takes the threshold ADC value as the one adjustable parameter.
- Published
- 2016
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33. The "temporary caging" technique for catheter navigation in patients with intracranial wide-necked aneurysms.
- Author
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Ito H, Onodera H, Wakui D, Uchida M, Sase T, Morishima H, Oshio K, and Tanaka Y
- Abstract
Endovascular treatment of wide-necked aneurysms with preservation of the parent artery remains a challenge. The authors describe a novel and simple technique to navigate a balloon or stent-delivery catheter across a wide-necked aneurysm in which previously existing methods could have failed to pass the catheter across the neck of the aneurysm, which we have named "temporary caging" technique. The technical results using this method are presented in 6 cases.
- Published
- 2015
34. Percutaneous transluminal angioplasty in a patient with internal carotid artery stenosis following gamma knife radiosurgery for recurrent pituitary adenoma.
- Author
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Ito H, Onodera H, Sase T, Uchida M, Morishima H, Oshio K, Shuto T, and Tanaka Y
- Abstract
Background: Intracranial vascular complications following radiosurgery are extremely rare., Case Description: We report a case of stenosis in the internal carotid artery 5 years after gamma knife radiosurgery for a recurrent pituitary adenoma. Percutaneous transluminal angioplasty was performed successfully with anatomical and functional improvement., Conclusion: These results suggested the importance of monitoring for arterial stenosis in the long-term follow-up. Moreover, this is the first case of endovascular treatment as an effective therapy for intracranial arterial stenosis due to radiotherapy.
- Published
- 2015
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35. Intraoperative head rotation for clipping anterior communicating artery aneurysms.
- Author
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Tanaka Y, Oshio K, Ito H, and Onodera H
- Abstract
Background: The anterior interhemispheric approach provides wide exposure of the anatomy around the anterior communicating artery aneurysm. A disadvantage of this approach is that splitting the interhemispheric fissure is a complicated surgical maneuver. One solution is to hold the fissure horizontally in the operation field. Surgical procedures for bicoronal scalp incision and craniotomy are difficult in the horizontal head position. We developed a modified low anterior interhemispheric approach to minimize damage to the frontal lobe and olfactory nerve by rotating the head after opening the dura., Methods: The head is fixed in a prerotated Sugita head holder in a neutral head position. Bicoronal scalp incision and frontal craniotomy are performed and the head holder is rotated 30 degrees clockwise to allow gravity to retract the right frontal lobe. The surgeon can then move to the right side of the patient to obtain a horizontal operation field parallel to the interhemispheric fissure., Results: This method was used for 12 patients in the past 6 years. All aneurysms were successfully clipped without any complications related to the procedure. Damage to the frontal lobe was avoided and the olfactory nerve was preserved in all the patients., Conclusion: Intraoperative head rotation minimizes surgical damage to the neural structures in the anterior interhemispheric approach.
- Published
- 2015
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36. Neuronal representation of duration discrimination in the monkey striatum.
- Author
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Chiba A, Oshio K, and Inase M
- Abstract
Functional imaging and lesion studies in humans and animals suggest that the basal ganglia are crucial for temporal information processing. To elucidate neuronal mechanisms of interval timing in the basal ganglia, we recorded single-unit activity from the striatum of two monkeys while they performed a visual duration discrimination task. In the task, blue and red cues of different durations (0.2-2.0 sec) were successively presented. Each of the two cues was followed by a 1.0 sec delay period. The animals were instructed to choose the longer presented colored stimulus after the second delay period. A total of 498 phasically active neurons were recorded from the striatum, and 269 neurons were defined as task related. Two types of neuronal activity were distinguished during the delay periods. First, the activity gradually changed depending on the duration of the cue presented just before. This activity may represent the signal duration for later comparison between two cue durations. The activity during the second cue period also represented duration of the first cue. Second, the activity changed differently depending on whether the first or second cue was presented longer. This activity may represent discrimination results after the comparison between the two cue durations. These findings support the assumption that striatal neurons represent timing information of sensory signals for duration discrimination., (© 2015 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of the American Physiological Society and The Physiological Society.)
- Published
- 2015
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37. Acute phase endovascular intervention on a pseudoaneurysm formed due to rupture of an anterior communicating artery aneurysm.
- Author
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Ito H, Morishima H, Onodera H, Wakui D, Uchida M, Sase T, Oshio K, and Tanaka Y
- Subjects
- Aged, Aneurysm, False diagnostic imaging, Aneurysm, False etiology, Cerebral Angiography, Female, Humans, Subarachnoid Hemorrhage diagnostic imaging, Subarachnoid Hemorrhage etiology, Treatment Outcome, Aneurysm, False therapy, Aneurysm, Ruptured complications, Embolization, Therapeutic methods, Endovascular Procedures methods, Intracranial Aneurysm complications, Subarachnoid Hemorrhage therapy
- Abstract
A 79-year-old woman presented with a subarachnoid hemorrhage. Angiography revealed pseudoaneurysm formation due to rupture of a true saccular anterior communicating artery aneurysm. Coil embolization, limited to the true aneurysm, was performed successfully with a favorable clinical outcome. This procedure can be considered as an alternative treatment option for similar aneurysms in cases where surgical clipping is contraindicated.
- Published
- 2014
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38. Interpretation of diffusion MR imaging data using a gamma distribution model.
- Author
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Oshio K, Shinmoto H, and Mulkern RV
- Subjects
- Humans, Male, Prostate pathology, Reproducibility of Results, Diffusion Magnetic Resonance Imaging methods, Diffusion Magnetic Resonance Imaging statistics & numerical data, Image Interpretation, Computer-Assisted methods, Models, Statistical, Prostatic Neoplasms diagnosis
- Abstract
Purpose: Although many models have been proposed to interpret non-Gaussian diffusion MRI data in biological tissues, it is often difficult to see the correlation between the MRI data and the histological changes in the tissue. Among these models, so called statistical models, which assume the diffusion coefficient D is distributed continuously within a voxel, are more suitable for interpreting the data in a histological context than others. In this work, we examined a statistical model based on the gamma distribution., Methods: First, the proposed gamma model, the bi-exponential model, and the truncated Gaussian model were compared for goodness of fit. To evaluate diagnostic capability, area fractions of certain D ranges were evaluated. The area fraction for D < 1.0 mm2/s (frac < 1) was attributed to small cancer cells with restricted diffusion, and the area fraction for D > 3.0 mm2/s (frac > 3) was considered to reflect perfusion component. A clinical data set of histologically proven prostate cancer cases from previous study was used., Results: For the cancer tissue, the gamma model was better fit than the truncated Gaussian model, and there was no significant difference between the gamma model and the bi-exponential model. For the normal peripheral zone tissue, there was no significant differences among all models. In the 2D scatter plot of frac < 1 vs. frac > 3, Cancer and non-cancer tissues were clearly separated., Conclusion: Using the proposed model, the diffusion MR data was well fit, and histological interpretation of the data appears possible.
- Published
- 2014
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39. Reduction in the vascular bed volume of uterine fibroids after hormonal treatment: evaluation with dynamic double-echo R₂* imaging.
- Author
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Okuda S, Oshio K, Asada H, Tanimoto A, Jinzaki M, Furuya M, Yoshimura Y, and Kuribayashi S
- Subjects
- Adult, Area Under Curve, Contrast Media, Female, Follow-Up Studies, Gadolinium DTPA, Gonadotropin-Releasing Hormone therapeutic use, Humans, Image Enhancement methods, Treatment Outcome, Uterus pathology, Young Adult, Antineoplastic Agents, Hormonal therapeutic use, Leiomyoma blood supply, Leiomyoma drug therapy, Magnetic Resonance Imaging methods, Uterine Neoplasms blood supply, Uterine Neoplasms drug therapy
- Abstract
Purpose: To demonstrate the reduction in vascular bed volume (VBV) of uterine fibroids after administration of gonadotropin-releasing hormone analogue (GnRHa) using magnetic resonance (MR) imaging including dynamic double-echo R₂* imaging (DDE-R₂*I) and to assess the value of DDE-R₂*I as a predictor of such reduction., Methods: Twenty-one women with uterine intramural fibroids underwent MR imaging including DDE-R₂*I before GnRHa treatment. DDE-R₂*I was acquired using a single-section, double-echo, fast spoiled gradient recalled acquisition in the steady state (SPGR) sequence. We calculated the area under the curve (AUC) of the signal intensity on R₂*I within a 3×3-cm²region of interest that served to represent the VBV. We repeated MR imaging after 2 administrations of GnRHa and repeated image analyses. We statistically analyzed correlations between (A) pre-treatment AUC (AUC(pre)) and AUC reduction and (B) AUC(pre) and volume reduction., Results: The interval between the 2 MR studies ranged from 56 to 119 days (mean: 80.4 days). The average volume of the fibroids before GnRHa treatment was 647.8 mL compared with 463.4 mL after the therapy (decreased by an average of 28.5%; P<0.0001). Meanwhile, measured AUC was reduced by 55.3% (483.4 vs. 206.5; P<0.0001). AUC(pre) correlated with volume reduction (r=0.68), but not AUC reduction., Conclusions: We confirmed reduction in the VBV of fibroids using DDE-R₂*I. The measurement of AUC(pre) on DDE-R₂*I aids prediction of fibroid volume reduction but correlates poorly with the percentage of AUC reduction.
- Published
- 2012
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40. Possible functions of prefrontal cortical neurons in duration discrimination.
- Author
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Oshio K
- Published
- 2011
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41. Accuracy of MR temperature measurement based on chemical shift change for radiofrequency ablation using hook-shaped electrodes.
- Author
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Okuda S, Kuroda K, Kainuma O, Oshio K, Fujiwara H, and Kuribayashi S
- Subjects
- Animals, Cattle, Electrodes, Equipment Design, Temperature, Catheter Ablation instrumentation, Hyperthermia, Induced, Liver surgery, Magnetic Resonance Imaging methods
- Abstract
The purpose of the current study is to evaluate the accuracy of MR thermometry for radiofrequency ablation (RFA) with hook-shaped electrodes. The objects were eight extracted bovine livers. The chemical shift change was calculated from MR images acquired with a spoiled gradient echo sequence and compared with the temperature directly measured with a thermocouple. Linear regression was established between them with a coefficient of -0.0110+/-0.0007 ppm/ degrees C and errors were calculated as -0.50+/-7.50 degrees C. MR thermometry is capable of monitoring temperature for RFA.
- Published
- 2004
- Full Text
- View/download PDF
42. Feasibility of internally referenced brain temperature imaging with a metabolite signal.
- Author
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Kuroda K, Takei N, Mulkern RV, Oshio K, Nakai T, Okada T, Matsumura A, Yanaka K, Hynynen K, and Jolesz FA
- Subjects
- Animals, Aspartic Acid analogs & derivatives, Aspartic Acid metabolism, Feasibility Studies, Phantoms, Imaging, Protons, Rabbits, Time Factors, Body Temperature, Body Water, Brain metabolism, Echo-Planar Imaging methods, Magnetic Resonance Spectroscopy methods
- Abstract
The feasibility of using a metabolite signal as an internal reference for self-referenced temperature distribution measurement was examined. Line scan echo-planar spectroscopic imaging (LSEPSI) was applied to obtain quick multi-voxel spectroscopic measurements and to avoid possible spectral degradation from motion. Temperature distribution in a rabbit brain in vivo was successfully visualized by means of the chemical shift of water, which was measured by using naturally abundant (up to 10 mM) N-acetyl-aspartate (NAA) as the reference signal. Unlike the phase-mapping approach, this technique does not require a pixel-by-pixel subtraction. Therefore, in theory, it is more resistant to inter-scan motion or changes in susceptibility. The spatial and temporal resolutions of this technique are 1.5 cm3 and 4.5 min. A higher signal-to-noise ratio and optimization of the water and outer-volume suppression capabilities will be required to further enhance the temperature-mapping capabilities.
- Published
- 2003
- Full Text
- View/download PDF
43. Fast spin-echo MR in the detection of vertebral metastases: comparison of three sequences.
- Author
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Jones KM, Schwartz RB, Mantello MT, Ahn SS, Khorasani R, Mukherji S, Oshio K, and Mulkern RV
- Subjects
- Adult, Aged, Aged, 80 and over, Female, Gastrointestinal Neoplasms pathology, Humans, Lung Neoplasms pathology, Male, Middle Aged, Prospective Studies, Urinary Bladder Neoplasms pathology, Magnetic Resonance Imaging methods, Spinal Neoplasms diagnosis, Spinal Neoplasms secondary
- Abstract
Purpose: To examine the relative capabilities for the detection of vertebral metastases of three available fast spin-echo sequences: T1-weighted fast spin-echo, short tau inversion recovery (STIR) fast spin-echo, and T2-weighted fast spin-echo sequences with chemical shift selective saturation pulse fat suppression., Methods: Fourteen patients were evaluated prospectively over a 2-month period with T1-weighted fast spin-echo (four echo train, four acquisitions, 1 min 59 sec-2 min 37 sec). STIR fast spin-echo (16 echo train, four acquisitions, 2 min 30 sec-3 min 19 sec), and T2-weighted fast spin-echo (16 echo train, 4 acquisitions, 2 min 27 sec-3 min 16 sec). For all three pulse sequences, measurements were obtained of the signal intensities of normal marrow, abnormal marrow, fat, and noise posterior to the spine. Contrast-to-noise ratios were calculated for metastases in each case. Lesions were evaluated by three observers and rated for size, location, and conspicuity., Results: Signal intensities of fat, normal marrow, and noise were highest for T1-weighted fast spin-echo sequences. STIR fast spin-echo and fat-suppressed T2-weighted fast spin-echo had approximately similar fat-suppression capabilities. Though contrast-to-noise ratios were highest overall for STIR fast spin-echo, the finding was not statistically significant and lesion conspicuity was deemed better with fat-suppressed T2-weighted fast spin-echo and T1-weighted fast spin-echo images. Discrete lesions were well identified on all three pulse sequences., Conclusion: Fast spin-echo sequences appear promising for the detection of vertebral metastases. Further work should be directed toward comparison with conventional spin-echo to determine whether fast spin-echo may replace conventional spin-echo sequences for evaluation of vertebral metastases.
- Published
- 1994
44. Fast spin-echo MR imaging of the cervical spine: influence of echo train length and echo spacing on image contrast and quality.
- Author
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Sze G, Kawamura Y, Negishi C, Constable RT, Merriam M, Oshio K, and Jolesz F
- Subjects
- Cervical Vertebrae pathology, Humans, Models, Structural, Prospective Studies, Spinal Diseases diagnosis, Cervical Vertebrae anatomy & histology, Magnetic Resonance Imaging methods
- Abstract
Purpose: To examine the interaction of echo train length and interecho spacing and their effects on image quality and contrast in fast spin-echo sequences of the cervical spine., Methods: Forty-three patients with suspected cervical disk disease were prospectively evaluated with fast spin-echo with varying echo train lengths and interecho spacing. A flow phantom was used to confirm findings related to cerebrospinal fluid pulsation. Parameters were manipulated to adjust contrast, signal-to-noise ratio, the effects of artifacts, and the speed of acquisition., Results: In general, increasing echo train length increased homogeneity and high intensity of cerebrospinal fluid signal and reduced acquisition time; however, it decreased the signal-to-noise ratio of cerebrospinal fluid and cord and increased blurring, and, to a lesser extent, edge enhancement, and "truncation-type" artifact. Increasing interecho space permitted the use of longer echo times but minimally decreased contrast and signal-to-noise ratio of cord and cerebrospinal fluid. In addition, increasing echo spacing increased blurring, edge enhancement, truncation-type, magnetic susceptibility, and motion artifacts., Conclusions: For cervical spine imaging, a long echo train length and short echo spacing partially compensate for cerebrospinal fluid flow and produce the best myelographic effect but must be modulated by other constraints, such as artifact production or technical capabilities.
- Published
- 1993
45. Fast spin-echo imaging in the evaluation of intradural disease of the spine.
- Author
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Sze G, Merriam M, Oshio K, and Jolesz FA
- Subjects
- Adult, Aged, Evaluation Studies as Topic, Female, Humans, Magnetic Resonance Imaging standards, Male, Middle Aged, Dura Mater pathology, Magnetic Resonance Imaging methods, Spinal Cord Diseases diagnosis
- Abstract
Purpose: Fast spin echo (FSE) images were compared with conventional images in 46 patients with intradural spinal disease to determine their accuracy in the detection and delineation of lesions., Materials and Methods: The images were interpreted by two neuroradiologists, who read individually. A total of 720 blinded readings formed the basis for this evaluation. A gold standard for each patient was selected, based on the blinded readings of the conventional studies., Results: In the sagittal plane, the FSE sequences were found to have an accuracy of 93% and 93% for the first reader and 93% and 85% for the second reader. For the axial plane, the corresponding figures were 86% and 82% for the first reader and 64% and 77% for the second reader. These figures compared favorably with conventional sequences. Similar delineation of lesions was noted in 78% of cases. In the remaining cases, there were no significant trends., Conclusion: Because of these findings, FSE sequences appear as accurate as conventional sequences. In this study, they were capable of supplanting conventional sequences in the evaluation of intradural pathology of the spine in the sagittal plane, although conventional sequences were still preferred in the axial plane.
- Published
- 1992
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