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Dive into the research topics where Yasuo Uesugi is active.

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Featured researches published by Yasuo Uesugi.


European Radiology | 1999

Esophageal varices before and after endoscopic variceal ligation: evaluation using helical CT.

Tadafumi Shimizu; Ryuichiro Namba; T. Matsuoka; Koujirou Tabuchi; Kazuhiro Yamamoto; Yasuo Uesugi; Ritsuo Matsui; Kozo Sueyoshi; Isamu Narabayashi

Abstract. The purpose of this study was to demonstrate the utility of helical CT in assessing the therapeutic effects of endoscopic variceal ligation (EVL). Twenty-four patients with esophageal varices were examined. Helical scanning was initiated 60 s after intravenous injection (Iopamidol 300 mgI/ml, total 120 ml, 3 ml/s) was started. Esophageal varices were clearly depicted as high-density areas. Multiplanar reformation and 3D images demonstrated collateral circulation three-dimensionally. After EVL, mucosal high-density areas had diminished markedly, but collateral veins around the esophagus, and gastro- and/or spleno-renal shunts, were unchanged in all patients. Of 21 patients with collateral circulation, esophageal varices recurred endoscopically in 6 patients within 12 months. In 3 patients without collateral circulation, esophageal varices did not recur within 12 months. From these findings, we conclude that helical CT is a useful method for assessing the therapeutic effects of EVL.


Brachytherapy | 2015

Preliminary results of MRI-assisted high-dose-rate interstitial brachytherapy for uterine cervical cancer

Ken Yoshida; Hideya Yamazaki; Tadashi Takenaka; Tadayuki Kotsuma; Shunsuke Miyake; Mari Ueda; Mineo Yoshida; Koji Masui; Yasuo Yoshioka; Yasuo Uesugi; T. Shimbo; Nobuhiko Yoshikawa; Hiroto Yoshioka; Kazumasa Aramoto; Yoshifumi Narumi; Shigetoshi Yamada; Keiji Tatsumi; Eiichi Tanaka

PURPOSE To investigate the effectiveness of our novel MRI-assisted high-dose-rate interstitial brachytherapy for uterine cervical cancer. METHODS AND MATERIALS Between June 2005 and June 2009, 29 previously untreated patients with cervical cancer were enrolled (2 T2b, 2 T3a, 19 T3b, and 6 T4 tumors). We implanted MRI-compatible plastic catheters using our unique ambulatory technique. The total treatment doses were 30-36 Gy (6 Gy per fraction) combined with external beam radiotherapy. RESULTS The median D90 (high-risk clinical target volume), D(2 cc) (bladder), and D(2 cc) (rectum) per fraction were 6.9, 5, and 4.6 Gy, respectively. The 3-year local control rates were 100%, 95%, and 83% for T2, T3, and T4 tumors, respectively. Grade 3 or 4 late complications occurred in 4 patients. CONCLUSIONS Our preliminary evaluation of image-based high-dose-rate interstitial brachytherapy showed favorable local treatment results with an acceptable complication rate.


International Journal of Clinical Oncology | 2003

Stereotactic radiosurgery (SRS) for multiple metastatic brain tumors : effects of the number of target tumors on exposure dose in normal brain tissues

Masatsugu Takahashi; Isamu Narabayashi; Toshihiko Kuroiwa; Yasuo Uesugi; Toshiaki Tatsumi; Taisuke Inomata

AbstractBackground. This study was carried out to clarify the practical limit of the number of stereotactic radiosurgery (SRS)-targeted tumors based on the irradiation dose of normal brain tissues. Methods. Twenty-five patients with multiple brain metastases who received SRS from October 1998 to May 2002 were enrolled in the study. In each patient, the treatment options were thoroughly studied before deciding upon a course of treatment. The number of irradiated targets was increased one by one until all of the targets were included in a treatment plan. Given a surface dose of 25 Gy, we calculated the dose volume histogram (DVH) for the entire brain in each treatment plan and compared it with those of other treatment plans. Ultimately, only 5 of the 25 patients received irradiation for all of their tumors; the others received selective irradiation targeting only those tumors that were causing symptoms. Results. When the number of targets increased, the DVH curve shifted to the right. The volume of the brain irradiated at a dose of 5 Gy or higher was 25.7% or less for 4 or fewer targets, 45.7% for 5–6 targets, 81.0% for 7–8 targets and 100% for 9–11 targets. When the number of the targets exceeded 8, more than 50% of the entire brain was irradiated at levels of at least 8.7 Gy. The dose distribution became very complex as the number of targets increased. Although the survival time of the group in which tumors were selectively targeted was longer than that in the group in which all tumors were irradiated, the difference between the two groups was not statistically significant (P = 0.2537). Conclusion. In SRS for multiple brain metastases, risks of both acute and late sequelae may increase because the exposure dose to normal brain tissues increases with increased numbers of target tumors. Dose distribution becomes more complex according to the increase in the number of targets. Based on our DVH curves, we conclude that the exposure dose to normal brain tissues is acceptable when the number of targets is less than 7. Importantly, our study also reveals that it may not be necessary or desirable to irradiate all metastatic tumors.


Molecular Medicine Reports | 2013

Sivelestat sodium hydrate reduces radiation-induced lung injury in mice by inhibiting neutrophil elastase

Nobuhiko Yoshikawa; Taisuke Inomata; Yoshikatsu Okada; T. Shimbo; Masatsugu Takahashi; Kazuhiko Akita; Yasuo Uesugi; Yoshifumi Narumi

The aim of this study was to investigate whether sivelestat, a neutrophil elastase (NE) inhibitor, mitigates radiation-induced lung injury in mice. C57BL/6J mice were administered a dose of 20 Gy to the bilateral whole lungs. Sivelestat was administered immediately before and 1 h after irradiation in group RE2, and immediately before and 1, 3 and 6 h after irradiation in group RE4. Group R received irradiation without sivelestat injection. Mice that did not receive sivelestat injection or irradiation were used as controls. NE activity was measured 24 and 48 h after irradiation, and the mice were sacrificed 24 h, 48 h and 15 weeks after irradiation for histopathological examination. In groups RE2 and RE4, NE activity was significantly suppressed until 48 h after irradiation compared to group R. The degree of lung damage in each group was scored during histopathological examination. Results showed that the scores of groups RE2 and RE4 were significantly lower compared to those of group R 15 weeks after irradiation. In conclusion, sivelestat reduced radiation‑induced lung injury in the mice by suppressing NE activity and excessive inflammatory reactions.


Head and Neck-journal for The Sciences and Specialties of The Head and Neck | 2009

Planned fractionated boron neutron capture therapy using epithermal neutrons for a patient with recurrent squamous cell carcinoma in the temporal bone: a case report.

Shin-Ichi Haginomori; Shin-Ichi Miyatake; Takaki Inui; Michitoshi Araki; Shinji Kawabata; Atsuko Takamaki; Koutetsu Lee; Hiroshi Takenaka; Toshihiko Kuroiwa; Yasuo Uesugi; Hiroaki Kumada; Koji Ono

We describe the first case of extensive squamous cell carcinoma in the temporal bone recurring after surgery, conventional radiotherapy, and chemotherapy, which was treated using planned fractionated boron neutron capture therapy (BNCT).


Clinical Nuclear Medicine | 2000

Tc-99m PMT whole-body scintigraphy for evaluation of therapeutic effect and for monitoring bone metastasis in a patient with hepatocellular carcinoma

Kozo Sueyoshi; Isamu Narabayashi; Kenji Doi; Masatugu Takahashi; Tuyoshi Komori; Yoshimitu Tatsu; Tomoaki Tatsumi; Keita Utunomiya; Yasuo Uesugi; Itaru Adachi; Tadafumi Shimizu

Detection of metastatic lesions by bone scintigraphy is highly sensitive but has a low rate of specificity. Often bone metastases from hepatocellular carcinoma are not detected by bone scintigraphy because of low uptake or a photopenic area in the tumor. In contrast, Tc-99m Sn-N-pyridoxy-5-methyltryptophan (Tc-99m PMT) whole-body scintigraphy reflects tumor viability, and the specificity of detection is so high that tumor structure can be shown well. Tc-99m PMT whole-body scintigraphy was helpful for evaluating the response to therapy and monitoring the course of the patient described here with bone metastasis from hepatocellular carcinoma.


Otology & Neurotology | 2003

Enlarged bony portion of the eustachian tube in oculoauriculovertebral spectrum

Shin-Ichi Haginomori; Ryuzaburo Nonaka; Hideaki Hoshijima; Masahiko Higashikawa; Hiroshi Takenaka; Yasuo Uesugi; Isamu Narabayashi

The patulous eustachian tube (ET) has been reported as the cause of cholesteatoma, otitis media, and tinnitus. Almost all reports on the patulous eustachian tube mentioned the patulous lumen in cartilaginous portion of the ET and atrophy of peritubal tissue, especially fat tissue. In contrast, enlarged bony portion of the ET is rare (1) and its pathophysiology remains unknown. Radiological studies are extremely useful to detect this anomaly. In this case of oculoauriculovertebral spectrum (OVAS), the multi-detector row computed tomography (1-mm collimation, 1-mm interval) reveals the enlarged bony portion of the left ET (Figs. 1 and 2). The width of the bony portion of the ET, which is closed to the junctional portion of the ET (2), is 7 mm and is much wider than that in normal children (1.5 mm) as reported by Suzuki et al (3) (Fig. 1). Huge bony dehiscence is recognized in the carotid canal (Fig. 2). Moreover, underdeveloped vestibule and semicircular canals, complete absence of the cochlea (Fig. 1 and 2), and anomalous ossicles are observed. In the right ear, which has a normal aspect in the middle ear and inner ear, the shape and width (1.3 mm) of the bony portion of the ET are normal (Fig. 3). Embryologically, the tubotympanic recess and primary tympanic cavity are derived from the expanding terminal end of the endoderm-lined first pharyngeal pouch and probably the second pharyngeal pouch (4). The endoderm of the tubotympanic recess approached the surface that comes in contact with the ectodermal membrane of the first branchial groove. Near the end of the second month, the tubotympanic recess undergoes a bottleneck constriction, then the medial constricted portion lengthens and becomes the ET (4). The bony portion


Operations Research Letters | 1998

Three-Dimensional Imaging of Laryngeal Cancers Using High-Speed Helical CT Scanning

Atsushi Sakakura; Yuzo Yamamoto; Yasuo Uesugi; Ken Nakai; Hiroshi Takenaka; Isamu Narabayashi

To evaluate the clinical usefulness and limitations of three-dimensional (3-D) imaging of laryngeal cancers by high-speed helical (spiral) CT scanning, 3-D images were reconstructed for one dissected human larynx and 10 patients with laryngeal cancer. The larynges were scanned in 1- to 2-mm slices, and were reconstructed using a slice thickness of 0.5–1.0 mm. The macroscopic (or endoscopic) findings and the 3-D CT images of the larynx were compared. The selected threshold CT values were –600 HU (Hounsfield units) to –100 HU for the mucous membranes, and 250 HU for bone. Under these conditions, almost all of the structures remained distinct. The 3-D images of the larynx obtained by helical CT were very helpful in understanding laryngeal anatomy, especially in the subglottic area, which cannot be seen clearly by endoscopy or conventional axial CT. Clinically, this system would have advantages in the detection of subglottic cancers, or the invasion of glottic or supraglottic cancers into the subglottic area.


Brachytherapy | 2015

Treatment results of image-guided high-dose-rate interstitial brachytherapy for pelvic recurrence of uterine cancer

Ken Yoshida; Hideya Yamazaki; Tadayuki Kotsuma; Tadashi Takenaka; Koji Masui; Yasuo Yoshioka; Yasuo Uesugi; T. Shimbo; Nobuhiko Yoshikawa; Hiroto Yoshioka; Yoshifumi Narumi; Keiji Tatsumi; Eiichi Tanaka

PURPOSE We analyzed clinical data to evaluate the effectiveness of image-guided high-dose-rate interstitial brachytherapy (HDR-ISBT) for pelvic recurrence of uterine cancer. METHODS AND MATERIALS Between 2003 and 2011, 56 patients were treated with HDR-ISBT with or without external beam radiotherapy (EBRT). The median followup time was 33 months (range, 1-109 months). Pre-ISBT treatments included radical hysterectomy for 35 patients (Group A), radical hysterectomy with postoperative radiotherapy for 8 patients (Group B), and radical radiotherapy for 13 patients (Group C). We initiated MRI-assisted CT-based planning for the last 49 patients. The median ISBT single fraction dose was 6 Gy. The median total doses were 30 and 54 Gy with and without EBRT (range, 30-50 Gy) for Group A, respectively and 48 Gy without EBRT for Groups B and C. RESULTS The 3-year local control (LC) rates were 85%, 75%, and 46% for Groups A, B, and C, respectively (p = 0.017). The 3-year LC rates were 84%, 73%, and 33% for clinical target volume at the time of HDR-ISBT of <10, 10-29, and ≥30 cc, respectively (p = 0.005). The 3-year LC results tended to be higher for patients whose D100 (clinical target volume) was equal or higher than 67.1 Gy (p = 0.098). A total of 13 late complications of Grades 3-5 occurred in 11 patients (20%). CONCLUSIONS Our image-guided HDR-ISBT for pelvic recurrence of uterine cancer provided good treatment outcomes. The treatment results for patients who underwent radical surgery with or without postoperative radiotherapy are better than those for patients who underwent radical radiotherapy.


Journal of Gynecologic Oncology | 2015

Role of vaginal pallor reaction in predicting late vaginal stenosis after high-dose-rate brachytherapy in treatment-naive patients with cervical cancer

Ken Yoshida; Hideya Yamazaki; Satoaki Nakamura; Koji Masui; Tadayuki Kotsuma; Hironori Akiyama; Eiichi Tanaka; Nobuhiko Yoshikawa; Yasuo Uesugi; T. Shimbo; Yoshifumi Narumi; Yasuo Yoshioka

Objective To assess actual rates of late vaginal stenosis and identify predisposing factors for complications among patients with previously untreated cervical cancer following high-dose-rate brachytherapy. Methods We performed longitudinal analyses of 57 patients using the modified Dische score at 6, 12, 18, 24, 36, and 60 months after treatment, which consisted of 15 interstitial brachytherapys and 42 conventional intracavitary brachytherapys, with a median follow-up time of 36 months (range, 6 to 144 months). Results More than half of the patients developed grade 1 (mild) vaginal stenosis within the first year of follow-up, and grade 2 (97.5%, moderate) to grade 3 (severe) stenosis gradually increased with time. Actual stenosis rates for grade 1, 2, and 3 were 97.5% (95% confidence interval [CI], 92.7 to 97.5), 60.7% (95% CI, 42.2 to 79.3), and 7.4% (95% CI, 0 to 18.4) at 3 years after treatment. Pallor reaction grade 2-3 at 6 months was only a statistically significant predisposing factor for grade 2-3 late vaginal stenosis 3 years or later with a hazard ratio of 3.48 (95% CI, 1.32 to 9.19; p=0.018) by a multivariate Cox proportional hazard model. Patients with grade 0-1 pallor reaction at 6 months showed a grade ≥2 vaginal stenosis rate of 53%, whereas the grade 2-3 pallor reaction group achieved a grade ≥2 vaginal stenosis rate at 3 years at 100% (p=0.001). Conclusion High-dose-rate brachytherapy was associated with high incidence of late vaginal stenosis. Pallor reaction grade 2-3 at 6 months was predictive of late grade 2-3 vaginal stenosis at 3 years after treatment. These findings should prove helpful for patient counseling and preventive intervention.

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T. Shimbo

Osaka Medical College

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