23 results on '"Kyoichi Kato"'
Search Results
2. Relationship Between Coronary Fractional Flow Reserve and Computational Fluid Dynamics Analysis in Moderate Stenosis of the Coronary Artery
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Daisuke Kittaka, Yuichi Nakai, Kyoichi Kato, and Hisaya Sato
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medicine.medical_specialty ,business.industry ,medicine.medical_treatment ,Ischemia ,Percutaneous coronary intervention ,Wall shear stress (WSS) ,General Medicine ,Fractional flow reserve ,Review ,medicine.disease ,Stenosis ,Focal stenosis lesion ,medicine.anatomical_structure ,Internal medicine ,Right coronary artery ,medicine.artery ,Computational fluid dynamics (CFD) ,Conventional PCI ,Cardiology ,Medicine ,Fractional flow reserve (FFR) ,business ,Artery ,Cardiac catheterization - Abstract
Background: Fractional flow reserve (FFR) is used to evaluate the need for percutaneous coronary intervention (PCI) in cases of moderate stenosis of the coronary artery. Recently, diagnostic imaging support with computational fluid dynamics (CFD) analysis has been garnering attention. This study defines the relationship between FFR conducted for cardiac catheterization and CFD analyses conducted using coronary computed tomography (CT) for moderate stenosis, in addition to considering whether wall pressure (WP) and wall shear stress (WSS) can be used to evaluate ischemia. Methods and Results: Cases in which FFR was measured via coronary CT and cardiac catheterization was performed within 3 months were collected retrospectively. In the CFD analysis, WP and WSS were calculated and compared with FFR. Three groups were created to compare results of CFD analysis and FFR values according to the location of the stenosis: the right coronary artery, the left anterior descending artery, and the left circumflex artery. There was a correlation between FFR and WSS according to CFD analysis for moderate stenosis of the coronary artery, with a cut-off value for treatment able to be calculated. Conclusions: The results of this study suggest that ischemia can be evaluated by conducting CFD analysis (WSS) using coronary CT.
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- 2021
3. Evaluation of Patients’ Radiation Exposure in Neuroendovascular Therapy ─Estimated dose by questionnaire investigation─
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Osamu Tajima, Hiroyuki Takahashi, Hajime Sakamoto, Takahiro Kageyama, Shigeki Kobayashi, Junichi Ono, Toshi Abe, Kyoichi Kato, Masaharu Imazeki, Tatsuya Kikuchi, Atsuko Tsukamoto, Ryota Hasegawa, Kazuhiko Sato, Kazuo Awai, Hiroaki Suzuki, Kohei Kawasaki, and Joji Oota
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Radiation exposure ,medicine.medical_specialty ,business.industry ,medicine ,Neurology (clinical) ,Radiology ,Cardiology and Cardiovascular Medicine ,business - Published
- 2014
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4. Usefulness of Virtual Vessel Images in PPI for Treatment of Complete Obstruction of Leg Arteries
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Yasuo Nakazawa, Daisuke Kittaka, Hisaya Sato, Yuichi Nakai, and Kyoichi Kato
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Leg ,medicine.medical_specialty ,Percutaneous ,business.industry ,Abdominal aorta ,Image processing ,Arteries ,General Medicine ,Common iliac artery ,Popliteal artery ,Catheter ,Virtual image ,Thromboembolism ,medicine.artery ,medicine ,Humans ,Radiology ,Tomography ,Radionuclide Imaging ,Tomography, X-Ray Computed ,business - Abstract
Following recent rapid advances in devices and treatment technology, indications for percutaneous peripheral intervention (PPI) have been expanded to include complex lesions (long-segment lesions, completely obstructed chronic lesions, etc.) and even lesions of the superficial femoral artery and arteries distal to the popliteal artery. However, when PPI is used for treatment of complete obstruction, treatment can take a long time or its outcome can be less satisfactory for reasons such as difficulty in assessing the vascular distribution/arrangement or the direction of calcification in the obstructed area or excessively long lesions. In the present study, we conducted three-dimensional image processing of CT data from leg arteries conventionally used for preoperative diagnosis. Using this processing technique, we created virtual images of the blood vessels of the completely obstructed area and mapped these virtual vessel images onto the fluoroscopic monitor image during catheter treatment. The usefulness of this technique for PPI was then evaluated. We succeeded in creating virtual vessel images of the completely obstructed parts of leg arteries with the use of preoperative CT images of leg arteries that we then mapped onto the fluoroscopic monitor images during treatment. We were successful in mapping virtual images onto the abdominal aorta in 96.8% of cases and in 95.7% with the common iliac artery. This technique is thus able to supply reliable information on vascular distribution/arrangement, suggesting that it can enable the surgeon to advance the treatment device precisely along the vessels, making it useful for treatment with PPI. The study additionally showed that differences in the angle of imaging affect the manual mapping of the CT images onto angiograms.
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- 2014
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5. Scheduled infliximab monotherapy to prevent recurrence of Crohnʼs disease following ileocolic or ileal resection: A 3-year prospective randomized open trial
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Kyoichi Kato, Ken Fukunaga, Masaki Iimuro, Koji Yoshida, Takayuki Matsumoto, Nobuyuki Hida, Shiro Nakamura, Kazuko Nagase, Naohisa Takeda, Koji Kamikozuru, Kazutoshi Hori, Hiroto Miwa, Risa Kikuyama, Hiroki Ikeuchi, Yoshio Ohda, and Yoko Yokoyama
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Adult ,Male ,medicine.medical_specialty ,Adolescent ,Colon ,medicine.drug_class ,Loading dose ,Inflammatory bowel disease ,Drug Administration Schedule ,Young Adult ,Crohn Disease ,Ileum ,Secondary Prevention ,medicine ,Humans ,Immunology and Allergy ,Prospective Studies ,Child ,Adverse effect ,Aged ,Crohn's disease ,Thiopurine methyltransferase ,biology ,business.industry ,Anti-Inflammatory Agents, Non-Steroidal ,Remission Induction ,Gastroenterology ,Antibodies, Monoclonal ,Middle Aged ,Prognosis ,medicine.disease ,Crohn's Disease Activity Index ,Infliximab ,Surgery ,biology.protein ,Corticosteroid ,Female ,Tomography, X-Ray Computed ,business ,Follow-Up Studies ,medicine.drug - Abstract
Background: Infliximab (IFX) is effective for remission induction and maintenance of Crohn's disease (CD). This trial assessed the efficacy of scheduled maintenance IFX monotherapy to prevent postoperative CD recurrence. Methods: Thirty-one CD patients who had ileocolic resection within the past 4 weeks were randomly assigned to scheduled IFX at 5 mg/kg intravenously every 8 weeks for 36 months (n = 15) or without IFX (control, n = 16). All patients were treated without immunomodulator or corticosteroid following surgery. The primary and secondary endpoints were remission rates at 12 and 36 months, defined as CD Activity Index (CDAI) ≤150, an International Organization for the Study of Inflammatory Bowel Disease (IOIBD) score
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- 2012
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6. Optimal apheresis treatment volume for the efficacy and safety of leukocytapheresis with cellsorba in patients with active ulcerative colitis
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Koji Yoshida, Hiroto Miwa, Nobuyuki Hida, Kyoichi Kato, Yoko Yokoyama, Ken Fukunaga, Risa Kikuyama, Naohisa Takeda, Takayuki Matsumoto, Koji Kamikozuru, Shiro Nakamura, Kazuko Nagase, Masaki Iimuro, and Yoshio Ohda
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Adult ,Male ,medicine.medical_specialty ,Adolescent ,Prednisolone ,Blood volume ,Inflammatory bowel disease ,Gastroenterology ,Young Adult ,Internal medicine ,medicine ,Humans ,Leukapheresis ,Prospective Studies ,Child ,Adverse effect ,Aged ,Blood Volume ,business.industry ,Incidence (epidemiology) ,Hematology ,General Medicine ,Middle Aged ,medicine.disease ,Ulcerative colitis ,Surgery ,Treatment Outcome ,Apheresis ,Concomitant ,Colitis, Ulcerative ,Female ,Safety ,business ,medicine.drug - Abstract
Background: Leukocytapheresis (LCAP) is used as an adjunct therapy for patients with active ulcerative colitis (UC). Although, LCAP is routinely performed at 3,000 mL per session, we were interested to see that if this can be replaced with bodyweight (BW) adjusted volume. Methods: In an open label prospective trial, the clinical response to BW adjusted LCAP (BWA-LCAP) was evaluated in 14 patients with active UC. Fourteen demography matched UC patients who had been treated with the routine 3,000 mL LCAP were randomly sampled from our database as a control group. All patients were given 10 weekly LCAP sessions. In the BWA-LCAP group, the processed blood volume (PBV) was set at 30 mL/kg × BW/session. Baseline demographic measures were not significantly different between the two groups. Results: The average PBV in the BWA-LCAP group was 1971.0 ± 330.0 mL, range 1,020–2,460. In both groups, the average UC clinical disease activity index, the endoscopic index, and the concomitant prednisolone dosage were significantly and equally reduced during the course of 10 LCAP. Accordingly, at the end of the trial, no significant difference was seen in any outcome measure between the two groups. However, a significantly higher incidence of adverse event (AE) was observed in the routine 3,000 mL LCAP group as compared with the BWA-LCAP group (P < 0.01). Conclusions: The outcomes of this investigation showed that the therapeutic efficacy of LCAP based on 30 mL/kg × BW is similar to the routine 3,000 mL per session LCAP. However, BWA-LCAP should be favored if one is to see the full potential of LCAP without AE. © 2011 Wiley Periodicals, Inc.
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- 2011
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7. Relevance of the Processed Blood Volume per Granulocyte and Monocyte Apheresis Session to its Clinical Efficacy in Patients With Ulcerative Colitis
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Risa Kikuyama, Takayuki Matsumoto, Mikio Kawai, Koji Yoshida, Masaki Iimuro, Koji Kamikozuru, Kyoichi Kato, Hiroto Miwa, Naohisa Takeda, Yoshiyuki Takei, Nobuyuki Hida, Shiro Nakamura, Kazuko Nagase, Tomoaki Kono, Ken Fukunaga, Yoshio Ohda, Koji Nogami, and Yoko Yokoyama
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medicine.medical_specialty ,business.industry ,Monocyte ,Blood volume ,Hematology ,Activity index ,Granulocyte ,medicine.disease ,Ulcerative colitis ,Gastroenterology ,Surgery ,Apheresis ,medicine.anatomical_structure ,Nephrology ,Internal medicine ,medicine ,In patient ,Clinical efficacy ,business - Abstract
Granulocyte/monocyte adsorption (GMA) has been introduced as an adjunct intervention for active ulcerative colitis (UC) patients. The processed blood volume (PV) per GMA session is an important factor for its efficacy because depletion of elevated/activated myeloid leukocytes is its main action. Hitherto, this aspect of GMA has been largely ignored. Thirty-three patients were enrolled for remission induction therapy with five weekly GMA sessions at a standard PV of 1800 mL, regardless of patients' bodyweight (BW). The patients were divided into three groups: high (H)BW (≥ 65 kg, n = 11), 50 kg ≤ medium (M)BW < 65 kg (n = 12), and low (L)BW (≤ 50 kg, n = 10). UC clinical activity index (CAI) was according to Lichtiger, and the clinical efficacies were evaluated at both one week post 3(rd) GMA (Week 4) and one week post 5(th) GMA (Week 6). The average BW was 70.9 ± 6.2 kg in HBW, 55.8 ± 4.5 kg in MBW, and 46.8 ± 1.2 kg in LBW, indicating the mean PV/BW in the three groups being 25.6 ± 2.12, 32.5 ± 2.50, and 38.7 ± 1.0 (mL/kg, P < 0.05), respectively. The LBW group consisted of female patients only. Significant improvements of CAI were seen before treatment at either Week 4 or Week 6 in all groups. A significantly higher remission rate was achieved in the LBW (80.0%) vs. MBW (33.3%) or HBW (27.3%) at Week 6 (P < 0.03). According to this GMA evaluation, the lower-limit of optimum PV/kg should be higher than 38.7 mL/kg for its potential clinical efficacy to be significantly greater than the routine GMA method. Additional BW-oriented GMA studies in larger and gender controlled cohorts of patients should strengthen our findings.
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- 2011
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8. Infliximab Therapy Impacts the Peripheral Immune System of Immunomodulator and Corticosteroid Naive Patients with Crohn' Disease
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Koji Yoshida, Yoshio Ohda, Masaki Iimuro, Risa Kikuyama, Hiroto Miwa, Takayuki Matsumoto, Koji Kamikozuru, Nobuyuki Hida, Naohisa Takeda, Shin-ichiro Kashiwamura, Ken Fukunaga, Yoko Yokoyama, and Kyoichi Kato
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Crohn's disease ,medicine.medical_specialty ,Hepatology ,business.industry ,medicine.drug_class ,Regulatory T cell ,Gastroenterology ,Interleukin ,medicine.disease ,Infliximab ,medicine.anatomical_structure ,Internal medicine ,Remission Induction Therapy ,Immunology ,medicine ,Corticosteroid ,Original Article ,Tumor necrosis factor alpha ,IL-2 receptor ,business ,medicine.drug - Abstract
†‡ § Background/Aims: Infliximab (IFX), an antibody to tumor necrosis factor, (TNF)-α has effi cacy in treating Crohn’s disease (CD). However, knowledge of the potential effects of IFX on patients’ immune profi les is lacking. The purpose of this study was to reveal the immunological effects of IFX. Methods: Twenty-two patients with a CD activity index (CDAI) of 194.2±92.9 and an average duration of disease of 3.26 months and 21 healthy controls were included. Patients were to have their fi rst IFX remission induction therapy with 3 infusions (5 mg/kg) at weeks 0, 2, and 6. Oral 5-aminosalicylic acid was the only ongoing medication in the patient population. Blood samples at baseline, 12 hours after the first infusion and at week 14 were labeled with anti-CD4/ CD25 antibodies for immunohistochemical measurement of regulatory T-cells (Treg). Serum cytokines and chemokines were measured by suspension array and ELISA. Results: CDAI signifi cantly decreased prior to the second IFX infusion (p
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- 2011
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9. Hand Hygiene during Mobile X-ray Imaging in the Emergency Room
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Yasuo Nakazawa, Toshiyuki Takahashi, Syogo Say, Mayumi Aso, Kazumasa Fujimura, Mitsuyoshi Yasuda, Kyoichi Kato, and Kazunori Kuroki
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Cross Infection ,medicine.medical_specialty ,Bacteria ,business.industry ,media_common.quotation_subject ,Medical equipment ,General Medicine ,Hand ,medicine.disease ,Surgery ,Disinfection ,Radiography ,Hygiene ,Surveys and Questionnaires ,Radiological weapon ,medicine ,Humans ,Medical emergency ,Emergency Service, Hospital ,Gloves, Protective ,Tomography, X-Ray Computed ,business ,Technology, Radiologic ,Working environment ,media_common - Abstract
A hand hygiene behavior questionnaire and environmental survey were conducted regarding the mobile X-ray system used in the emergency room. As a result, among a total of 22 radiological technologists at this hospital who replied to the questionnaire, 18 wore disposable gloves when performing X-ray imaging using the mobile system. Among those 18, 11 were found to touch computed radiology (CR) consoles and HIS/RIS terminals while still wearing the gloves, thus creating the potential for spreading pathogens to other medical equipment and systems. According to the results of an environmental survey of the emergency imaging preparation room, the highest levels of bacteria were detected on CR consoles and HIS/RIS terminals. A possible reason for this is that these locations are not wiped down and cleaned as a part of routine cleaning and disinfection protocols, thus demonstrating the importance of cleaning and disinfection. Hand hygiene by medical personnel and appropriate cleaning and disinfecting of the working environment are important for preventing the spread of nosocomial infections. Radiological technologists are also required to take effective measures against infections in consideration of the high frequency of contact with both infected patients and patients susceptible to infections.
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- 2011
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10. Stereometry of the Prostate Using MRI-A Comparison Between TRUS, CT, and MRI
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Keigo Okabe, Hajime Saito, Chikara Noda, Kyoichi Kato, Yasuo Nakazawa, and Toshiyuki Takahashi
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Male ,medicine.medical_specialty ,medicine.diagnostic_test ,business.industry ,medicine.medical_treatment ,Ultrasound ,Prostate ,Computed tomography ,Magnetic resonance imaging ,Organ Size ,General Medicine ,Treatment parameters ,Prostate carcinoma ,urologic and male genital diseases ,Magnetic Resonance Imaging ,Radiation therapy ,medicine.anatomical_structure ,Humans ,Medicine ,Radiology ,Tomography, X-Ray Computed ,business ,Ultrasonography - Abstract
I-125 permanently implanted sealed-source radiotherapy is one of the treatments for early localized prostate carcinoma. In order to choose treatment parameters such as the number of implanted sources, accurately determining the volume of the prostate is vital for this type of therapy. We compared the usefulness of transrectal ultrasound (TRUS), computed tomography (CT), and magnetic resonance imaging (MRI) for preoperative stereometry of the prostate, and we further reviewed the utility of the MRI measurement. We performed prostate stereometry with TRUS, CT, and MRI in each of 45 patients who had provided informed consent. Taking TRUS stereometry as the standard, we computed the correlation of the MRI results with TRUS, and that of the CT results with TRUS, and found that MRI had a higher correlation.
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- 2008
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11. Exposed Dose Comparison between Coronary Computed Tomographic Angiography and Coronary Angiography: Basic Examination by Phantom
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Toshiyuki Takahashi, Hiroyuki Watanabe, Yoshimasa Takahashi, Kazumasa Fujimura, Hisaya Sato, Yasuhiro Imai, Syogo Sai, Yasuo Nakazawa, and Kyoichi Kato
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Coronary angiography ,medicine.medical_specialty ,Dosimeter ,medicine.diagnostic_test ,Phantoms, Imaging ,business.industry ,Dose comparison ,General Medicine ,Dose distribution ,Coronary Angiography ,Radiation Dosage ,Imaging phantom ,Soft plaque ,Computed tomographic angiography ,Medicine ,Fluoroscopy ,Radiology ,Radiometry ,Nuclear medicine ,business ,Tomography, Spiral Computed - Abstract
The new type of coronary angiography(CAG)that uses 40 mm volumetric computed tomography(VCT)has great potential for cardiac disease. However, it is still necessary to be cognizant of exposure dose. We measured doses of CAG by both VCT and cardiovascular X-ray using a body phantom within 170 glass dosimeters. VCT protocols were 120 kV, 570 mA, and 0.35 sec/rot with and without the dose-reduction features(small cardiac X-ray beam filter and ECG mA modulation). The cardiovascular X-ray protocol was Auto(65 - 77 kV)kV, Auto(41 - 46 mA)mA, 5 secx11 shots+11 min fluoroscopy(minimum protocol for screening). VCT with and without the dose-reduction features has the same dose distribution, however, the dose-reduction features reduced the amount of dose by about 40-50%. For VCT with those features, measured dose was about 70 mGy in the cardiac area and 60 mGy at the skin of the back, whereas those of cardiovascular X-ray were 10 mGy and 30 mGy. We measured detailed dose distributions and variations in the phantom, and we also demonstrated the possibility of VCT's dose-reduction features. The CT dose was still higher than that of cardiovascular X-ray, however, there were advantages of CT scanning, for instance, information about calcification, soft plaque, and 3D visualization. We think it is important to use both systems with an understanding of their advantages and limitations.
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- 2007
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12. Permanent hair removal with a diode-pumped Nd:YAG laser: a pilot study using the direct insertion method
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Teruko Ebisawa, Motoichiro Kogure, Ken Hashimoto, Kyoichi Kato, Timothy L. Irwin, Keiko Tezuka, and Toshimitsu Osawa
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Adult ,Male ,medicine.medical_specialty ,Burst frequency ,Pilot Projects ,Dermatology ,Terminal hair ,Hair Removal ,law.invention ,law ,otorhinolaryngologic diseases ,Hair removal ,Humans ,Medicine ,Diode ,integumentary system ,business.industry ,Middle Aged ,Laser ,Hair follicle ,Surgery ,medicine.anatomical_structure ,Skin color ,Nd:YAG laser ,Laser Therapy ,sense organs ,business ,Hair ,Biomedical engineering - Abstract
Background The removal of unwanted hair with various laser systems and related procedures has been investigated for many years. All researchers have met difficulty when trying to achieve "permanent" hair removal. In addition, damage to the epidermis and other complications, including hyper- or hypopigmentation in pigmented skin, have occurred because the laser energy was applied indirectly to the hair bulb through the epidermis. Objective To achieve permanent hair removal with the use of a diode-pumped neodymium:yttrium-aluminum-garnet laser system with an insulated optical needle. Also, to establish laser treatment parameters that allow for quick and effective removal of hair with minimal pain and no long-term medical complications. Method The laser used in the study was capable of producing up to 500 mJ of energy per burst at a 1,064-nm wavelength. A pulse width of 200-500 μs and a burst frequency of 100-200 Hz could be selected, and both defined a subset of the treatment parameter space. An optical needle, typically 130 μm in diameter, was prepared before each new treatment was conducted. Three bursts of energy, 300 mJ each, with a 300-millisecond interval, were delivered through the optical needle into each hair follicle. Between 200 and 300 shin hairs, typically terminal hairs, on each of 5 volunteers were treated. These volunteers were observed over 18.5-30 months for the regrowth of hairs by hair count. Results At the end of the observation period (6-30 months after the last treatment), 3 of 5 volunteers showed permanent loss of 76%-94.3% of their unwanted hair. One volunteer lost 34.8% of the original hair, but regrown hair was much thinner than the original terminal hair. One volunteer lost only 22.8% of the original hair, and regrown hair was coarse terminal hair. Except for the loss of hair, no change in skin texture, sensation, or skin color was observed. Conclusion The direct insertion optical method (DIOM), delivering laser energy directly to the hair bulb through an optical needle, has proven to be effective and achieves permanent hair removal in 60% of volunteers without medical complications.
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- 2003
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13. Evaluation of MRI Coronary Bypass Graft Patency Using the Volume-rendering Method
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Katsuyuki Moriya, Kyoichi Kato, Masaru Sonoda, Mika Ito, Yasuo Nakazawa, Toshiyuki Takahashi, Tomonari Funata, and Hisaya Sato
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Aorta ,medicine.medical_specialty ,Graft patency ,business.industry ,medicine.artery ,Medicine ,Volume rendering ,General Medicine ,Sensitivity (control systems) ,Radiology ,business - Published
- 2001
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14. A new reference point for patient dose estimation in neurovascular interventional radiology
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Kazuhiko Sato, Kyoichi Kato, Atsuko Tsukamoto, Hiroyuki Takahashi, Hajime Sakamoto, Jyoji Ota, Masaharu Imazeki, Ryota Hasegawa, Osamu Tajima, Shinichi Shiba, Kohei Kawasaki, Tatsuya Kikuchi, Kazuo Awai, Takahiro Kageyama, and Hiroaki Suzuki
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Adult ,Male ,medicine.medical_specialty ,Safety Management ,medicine.medical_treatment ,Physical Therapy, Sports Therapy and Rehabilitation ,Radiology, Interventional ,Radiation Dosage ,Imaging phantom ,Young Adult ,Radiation Monitoring ,Medicine ,Dosimetry ,Humans ,Radiology, Nuclear Medicine and imaging ,Projection (set theory) ,Aged ,Aged, 80 and over ,Radiation ,medicine.diagnostic_test ,business.industry ,Isocenter ,Interventional radiology ,General Medicine ,Middle Aged ,Reference Standards ,Neurovascular bundle ,Radiation therapy ,Cerebrovascular Circulation ,Female ,Radiology ,Tomography ,business ,Tomography, X-Ray Computed ,Head - Abstract
In interventional radiology, dose estimation using the interventional reference point (IRP) is a practical method for obtaining the real-time skin dose of a patient. However, the IRP is defined in terms of adult cardiovascular radiology and is not suitable for dosimetry of the head. In the present study, we defined a new reference point (neuro-IRP) for neuro-interventional procedures. The neuro-IRP was located on the central ray of the X-ray beam, 9 cm from the isocenter, toward the focal spot. To verify whether the neuro-IRP was accurate in dose estimation, we compared calculated doses at the neuro-IRP and actual measured doses at the surface of the head phantom for various directions of the X-ray projection. The resulting calculated doses were fairly consistent with actual measured doses, with the error in this estimation within approximately 15 %. These data suggest that dose estimation using the neuro-IRP for the head is valid.
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- 2013
15. [Clinical study to obtain true view of the glenohumeral joint on scapula-45]
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Hiroaki Tsutsui, Hironobu Fujisawa, Kenichi Mihara, Naoya Nishinaka, Hiroki Nishimura, Kyoichi Kato, and Yasuo Nakazawa
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musculoskeletal diseases ,Adult ,Inferior angle of the scapula ,medicine.medical_specialty ,Adolescent ,Radiography ,Kyphosis ,Coracoid process ,Rotator Cuff ,Scapula ,medicine ,Humans ,Rotator cuff ,Acromion ,Child ,Joint (geology) ,Technology, Radiologic ,Aged ,Orthodontics ,Aged, 80 and over ,business.industry ,Shoulder Joint ,General Medicine ,Middle Aged ,musculoskeletal system ,medicine.disease ,medicine.anatomical_structure ,Physical therapy ,business - Abstract
Scapula-45 is an original roentogenographical technique to clarify objectively the function of the rotator cuff and scapulothoracic joint. This examination enables assessment of the function of the rotator cuff and scapulothoracic joint utilizing the radiographs of the glenohumeral joint. However, in the former technique, it was difficult for the technician to properly align the patient for the view of the true glenohumeral joint because of the individual postural difference of the patients, such as kyphosis. In the present study, we reported a new technique with the use of the acromion, coracoid process, and inferior angle of the scapula as a landmark to obtain the consistent radiographs of the glenohumeral joint.
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- 2012
16. Comparison of different volumes of saline flush in the assessment of perivenous artefacts in the subclavian vein during cervical CT angiography
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Takaki Hayashi, Yoshimitsu Ohgiya, Nobuyuki Takeyama, T Hashimoto, Yuko Kinebuchi, D Takasu, J Nakashima, T Takahashi, Kyoichi Kato, and Takehiko Gokan
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Aortic arch ,Adult ,Male ,medicine.medical_specialty ,Contrast Media ,Sodium Chloride ,Saline flush ,Subclavian Vein ,medicine.artery ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Vein ,Aged ,Retrospective Studies ,Aged, 80 and over ,medicine.diagnostic_test ,Full Paper ,business.industry ,General Medicine ,Middle Aged ,medicine.anatomical_structure ,Angiography ,cardiovascular system ,Vertebrobasilar artery ,Female ,Radiology ,business ,Nuclear medicine ,Artifacts ,Tomography, X-Ray Computed ,Subclavian vein ,Artery ,Circle of Willis - Abstract
The aim of this study was to examine attenuation values in the central vein and perivenous artefacts at the subclavian vein in cervical CT angiography (CTA) when using 40 ml contrast material (CM) followed by different volumes (25 ml vs 40 ml) of saline flush (SF).61 patients underwent CTA between the aortic arch (AA) and distal to the circle of Willis (cW). After calculating test-bolus time to peak enhancement at the cW (Tc), scanning delay was represented as [(Tc + 4) - scan duration between AA and cW] s. 28 patients (Group A) received 40 ml of 370 mg iodine (I) ml(-1) CM followed by 25 ml of SF, and 33 patients (Group B) received the same CM followed by 40 ml of SF, both administered through the right antecubital vein. Arterial attenuation was measured at seven points in the aorto-carotid artery and at three points in the vertebrobasilar artery. Venous attenuation in the central vein was measured at four points. Mean attenuation values were analysed quantitatively. Axial and post-processing three-dimensional images were assessed qualitatively.When Groups A and B were compared, there were no differences in the mean attenuation values in either the aorto-carotid artery (p=0.78) or the vertebrobasilar artery (p=0.82). Mean venous attenuation values were lower (p=0.002) in Group B than in Group A. Although the qualitative assessment of arterial images showed no differences between the two groups overall, perivenous artefacts at the subclavian vein were assessed as less prominent (p0.01) in Group B.When compared with CTA followed by 25 ml of SF, CTA followed by 40 ml of SF can reduce venous attenuation values and perivenous artefacts at the subclavian vein.
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- 2010
17. [Radiation dose reduction using a non-linear image filter in MDCT]
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Toshiyuki Takahashi, Yoshimasa Takahashi, Junya Nakashima, Yasuhiro Imai, Yotaro Ishihara, Yasuo Nakazawa, and Kyoichi Kato
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medicine.medical_specialty ,Computer science ,Phantoms, Imaging ,Radiation dose ,Urography ,General Medicine ,Radiation Dosage ,Composite image filter ,Imaging phantom ,Reduction (complexity) ,Nonlinear system ,Liver ,Filter (video) ,Contrast injection ,medicine ,Image noise ,Humans ,Radiology ,Tomography, X-Ray Computed ,Lung ,Biomedical engineering - Abstract
The development of MDCT enabled various high-quality 3D imaging and optimized scan timing with contrast injection in a multi-phase dynamic study. Since radiation dose tends to increase to yield such high-quality images, we have to make an effort to reduce radiation dose. A non-linear image filter (Neuro 3D filter: N3D filter) has been developed in order to improve image noise. The purpose of this study was to evaluate the physical performance and effectiveness of this non-linear image filter using phantoms, and show how we can reduce radiation dose in clinical use of this filter. This N3D filter reduced radiation dose by about 50%, with minimum deterioration of spatial reduction in phantom and clinical studies. This filter shows great potential for clinical application.
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- 2010
18. Comparison of 40 and 60 milliliters of contrast in assessment of the carotid artery by computed tomography angiography
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Yuko Kinebuchi, Nobuyuki Takeyama, Takaki Hayashi, Tadashi Kitahara, M. Obuchi, Y. Takahashi, Seishi Matsui, T. Fujimoto, Kyoichi Kato, Takehiko Gokan, H. Itokawa, H. Shinjyo, and Yoshimitsu Ohgiya
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Aortic arch ,Male ,medicine.medical_specialty ,Carotid arteries ,media_common.quotation_subject ,Contrast Media ,medicine.artery ,medicine ,Contrast (vision) ,Humans ,Radiology, Nuclear Medicine and imaging ,Computed tomography angiography ,media_common ,Aged ,Aged, 80 and over ,Radiological and Ultrasound Technology ,medicine.diagnostic_test ,business.industry ,Angiography ,General Medicine ,Middle Aged ,Intracranial Arteriosclerosis ,medicine.anatomical_structure ,Carotid Arteries ,Female ,Radiology ,Tomography ,business ,Nuclear medicine ,Tomography, X-Ray Computed ,Artery ,Circle of Willis ,Iodine - Abstract
Background: Although fast acquisition of multidetector-row computed tomography (MDCT) can make it possible to acquire sufficient early vascular enhancement using small volumes and high concentrations of contrast material (CM), there are still some problems with nephrotoxicity and costs related to CM. Purpose: To compare the qualitative and quantitative performance in cervicocranial CT angiography (CTA) using two different iodine volumes and concentrations of CM. Material and Methods: CTA ranging from the aortic arch (AA) to distal to the circle of Willis (cW) was performed on a 32-MDCT system. Fifty-eight patients were randomly divided into two groups: group A (29 patients) received 60 ml of 300 mg I/ml CM, and group B (the other 29 patients) received 40 ml of 370 mg I/ml CM. Time to peak arterial enhancement at cW (Tc) was calculated. As scan speed was 96.9 mm/s and injection rate was 4.0 ml/s, scanning delay was individually decided according to Tc and scan duration between AA and cW. Arterial attenuation along the z-axis at eight points in the carotid-cerebral artery and venous attenuation of the internal jugular vein (IJV) at carotid bifurcation were measured. Mean attenuation values were then quantitatively analyzed. Postprocessing images were qualitatively assessed. Results: Arterial attenuation profiles revealed maximum attenuation at the distal common carotid artery in both groups. Although there were no significant differences in mean arterial attenuation in group A versus group B (402±70 HU vs. 407±67 HU; P=0.78), venous attenuation of the IJV was lower in group B than in group A (114±57 HU vs. 224±81 HU; P Conclusion: Although a different amount of CM was administered in both groups, quantitative and qualitative arterial images did not show significant differences between the two groups.
- Published
- 2008
19. A Prospective Randomised Double Blind Placebo Controlled Trial to Assess the Efficacy of a Chinese Herbal Medicine 'Xilei San' as Remission Induction and Maintenance Therapy in Patients With Refractory Ulcerative Proctitis
- Author
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Hiroto Miwa, Koji Yoshida, Naohisa Takeda, Yoko Yokoyama, Kyoichi Kato, Masaki Iimuro, Ken Fukunaga, Risa Kikuyama, Koji Kamikozuru, Takayuki Matsumoto, Nobuyuki Hida, Shiro Nakamura, and Yoshio Ohda
- Subjects
medicine.medical_specialty ,Hepatology ,business.industry ,Gastroenterology ,Placebo-controlled study ,Double blind ,Remission induction ,Maintenance therapy ,Refractory ,Ulcerative proctitis ,Internal medicine ,Physical therapy ,medicine ,In patient ,business - Published
- 2011
- Full Text
- View/download PDF
20. T1251 Prospective Randomized Double Blind Sham Controlled Study to Assess the Clinical Efficacy of Monthly Selective Granulocyte/Monocyte Adsorption as Maintenance Therapy in Steroid Refractory Ulcerative Colitis Patients
- Author
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Shiro Nakamura, Koji Yoshida, Kyoichi Kato, Yoshio Ohda, Takayuki Matsumoto, Koji Kamikozuru, Ken Fukunaga, Hiroto Miwa, Yoko Yokoyama, Nobuyuki Hida, and Naohisa Takeda
- Subjects
medicine.medical_specialty ,Hepatology ,business.industry ,Monocyte ,Gastroenterology ,Granulocyte ,medicine.disease ,Ulcerative colitis ,Surgery ,Double blind ,medicine.anatomical_structure ,Maintenance therapy ,Internal medicine ,medicine ,Clinical efficacy ,Steroid refractory ,business - Published
- 2010
- Full Text
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21. Usefulness of Rotating Cholangiography Using Advantx system(2nd report)
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Toshio Take, T. Nishizawa, Yasuo Nakazawa, M. Ito, Masaru Nitta, Hisaya Sato, Kyoichi Kato, and Hiroshi Ishii
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medicine.medical_specialty ,Cholangiography ,medicine.diagnostic_test ,business.industry ,Medicine ,General Medicine ,Radiology ,business - Published
- 1997
- Full Text
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22. Usefulness of Rotating Cholangiography Using Advantx system
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Masayuki Akiyama, Hisaya Sato, Masaru Nitta, Hiroshi Ishii, Yasuo Nakazawa, Toshio Take, K Okada, and Kyoichi Kato
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medicine.medical_specialty ,Cholangiography ,medicine.diagnostic_test ,business.industry ,Medicine ,General Medicine ,Radiology ,business - Published
- 1996
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23. Controlled trial of thyrotropin releasing hormone tartrate in ataxia of spinocerebellar degenerations
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Masanori Uono, Motoji Miyazaki, Masao Kinoshita, Akihiro Igata, Terunori Mitsuma, Tadao Tsubaki, Kazuya Ando, Akira Sakuma, Noriyuki Nihei, Takao Nakanishi, Kyoichi Kato, Shoichi Maruyama, Mitsuo Yoshida, Itsuro Sobue, and Tetsuya Takayanagi
- Subjects
Adult ,Male ,medicine.medical_specialty ,Ataxia ,Cerebellar Ataxia ,Gastrointestinal Diseases ,Nausea ,Thyrotropin-releasing hormone ,Olivary Nucleus ,Placebo ,Spinal Cord Diseases ,law.invention ,Efficacy ,Double-Blind Method ,Randomized controlled trial ,law ,Pons ,Internal medicine ,medicine ,Humans ,Thyrotropin-Releasing Hormone ,Aged ,Clinical Trials as Topic ,Cerebellar ataxia ,business.industry ,Syndrome ,Middle Aged ,Clinical trial ,Endocrinology ,Neurology ,Anesthesia ,Female ,Neurology (clinical) ,medicine.symptom ,business - Abstract
The clinical efficacy, dose-response relationship, and safety of TRH-T (thyrotropin releasing hormone tartrate) were assessed in 290 patients with spinocerebellar degeneration (SCD) in a 2-week, double-blind study using placebo as control. 254 patients satisfied the criteria for inclusion in evaluation of the drug efficacy. The patients were treated with TRH-T in an intramuscular dose of 2 mg, 0.5 mg or 0 mg (placebo) as TRH once a day for 2 weeks. Clinical responses to these treatments were evaluated 3 times: at the end of weeks 1 and 2 of treatment and a week after the end of treatment. The results of "global improvement rating" as well as those of "ataxia improvement rating" showed that both 2 mg and 0.5 mg TRH-T treatments were significantly superior to placebo treatment in patients with predominantly cerebellar form of SCD. The effect was well maintained a week after the end of the 2-week treatment in the patients who were given TRH-T in daily dose of 2 mg and showed improvement at the end of treatment. The results of "improvement rating of each symptom" revealed that 2 mg treatment was significantly more effective than placebo for disorders of standing, gait, speech and writing. In the patients who had no pyramidal involvement or disorder of deep sensation, the drug efficacy and dose-response relationship were evident. Adverse reactions to the drug such as headache, feeling febrile and nausea were observed in 50% of the patients on 2 mg treatment, in 38% of those on 0.5 mg treatment and in 21% of those on placebo patient, however, discontinued treatment because of adverse reactions.
- Published
- 1983
- Full Text
- View/download PDF
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