176 results on '"Ryoichi, Kato"'
Search Results
2. Hybrid repair for Kommerell’s diverticulum and right aortic arch with aberrant right vertebral artery
- Author
-
Mika Noda, Hiroshi Ishikawa, Yoshiyuki Takami, Yusuke Sakurai, Kentaro Amano, Kiyotoshi Akita, Tatsuo Banno, Ryoichi Kato, and Yasushi Takagi
- Subjects
kommerell’s diverticulum ,right-sided aortic arch ,aberrant right vertebral artery ,Medicine (General) ,R5-920 - Abstract
Kommerell’s diverticulum (KD) is a rare aneurysm of the origin of an aberrant subclavian artery. Hybrid aortic arch repair for KD is being performed more often. We report hybrid arch repair for KD in a 63-year-old man with a right aortic arch and aberrant right vertebral artery, an extremely rare variant. We performed total arch replacement to completely reconstruct the five cervical arteries with elephant trunk to create an adequate landing zone, followed by second-stage endovascular stent-grafting from the ascending aorta to the proximal descending aorta.
- Published
- 2022
- Full Text
- View/download PDF
3. Urgent intraoperative endovascular stent placement to resolve acute hepatic or portal venous obstruction during liver surgery: a case series
- Author
-
Yutaro Kato, Atsushi Sugioka, Masayuki Kojima, Junichi Yoshikawa, Yoshinao Tanahashi, Sanae Nakajima, Akira Yasuda, Gozo Kiguchi, Yuichiro Uchida, Toshihiro Yasui, Tatsuya Suzuki, Hokuto Akamatsu, Ryota Hanaoka, Hiroyuki Nagata, Ryoichi Kato, and Ichiro Uyama
- Subjects
Endovascular stenting ,Vascular reconstruction ,Self-expandable metallic stent ,SEMS ,Interventional radiology ,Hepatic vein ,Surgery ,RD1-811 - Abstract
Abstract Background Acute obstruction of the hepatic vein (HV) or the portal vein (PV), particularly when it occurs during liver surgery, is potentially fatal unless repaired swiftly. As surgical interventions for this problem are technically demanding and potentially unsuccessful, other treatment options are needed. Case presentation We report two cases of acute, surgically uncorrectable HV or PV obstruction during liver resection or living donor liver transplantation (LDLT), which was successfully treated with urgent intraoperative placement of endovascular stents using interventional radiology (IVR). In Case 1, a patient with colonic liver metastases underwent a non-anatomic partial hepatectomy of the segments 4 and 8 with middle hepatic vein (MHV) resection. Additionally, the patient underwent an extended right posterior sectionectomy with right hepatic vein (RHV) resection for tumors involving RHV. Reconstruction of the MHV was needed to avoid HV congestion of the anterior section of the liver. The MHV was firstly reconstructed by an end-to-end anastomosis between the MHV and RHV resected stumps. However, the reconstruction failed to retain the HV outflow and the anterior section became congested. Serial trials of surgical revisions including re-anastomosis, vein graft interposition and vein graft patch-plasty on the anastomotic wall failed to recover the HV outflow. In Case 2, a pediatric patient with biliary atresia underwent an LDLT and developed an intractable PV obstruction during surgery. Re-anastomosis with vein graft interposition failed to restore the PV flow and elongated warm ischemic time became critical. In both cases, the misalignment in HV or PV reconstruction was likely to have caused flow obstruction, and various types of surgical interventions failed to recover the venous flow. In both cases, an urgent IVR-directed placement of self-expandable metallic stents (SEMS) restored the HV or PV perfusion quickly and effectively, and saved the patients from developing critical conditions. Furthermore, in Cases 1 and 2, the SEMS placed were patent for a sufficient period of time (32 and 44 months, respectively). Conclusions The IVR-directed, urgent, intraoperative endovascular stenting is a safe and efficient treatment tool that serves to resolve the potentially fatal acute HV or PV obstruction that occurs in the middle of liver surgery.
- Published
- 2021
- Full Text
- View/download PDF
4. Measurement of effective renal plasma flow using model analysis of dynamic CT in the preoperative evaluation of the renal transplant donors
- Author
-
Yumi Kataoka, Hitoshi Nishio, Ryo Matsukiyo, Ryoichi Kato, Midori Hasegawa, Takashi Kenmochi, Ryoichi Shiroki, Hiroshi Toyama, Takashi Ichihara, and Shigeki Kobayashi
- Subjects
low radiation dose ct ,dynamic ct ,effective renal plasma flow ,Medicine (General) ,R5-920 - Abstract
Objectives: Renal scintigraphy is widely used to evaluate residual function of a transplanted kidney from the donor. Dynamic computed tomography (CT) imaging can evaluate both kidney morphology and regional renal function. The aim of this study was to develop an imaging protocol and a calculation method using dynamic CT for assessing the effective renal plasma flow (ERPF) by model analysis, and to evaluate the validity of the obtained ERPF values. Methods: Preoperative dynamic CT examination with a low radiation dose exposure system was performed for 25 renal transplant donors, and ERPF was calculated from the obtained images (CT-ERPF). To calculate CT-ERPF, we set the region of interest (ROI) in the renal cortex using automatic ROI-setting software developed in our laboratory. We compared the processing time with automatic and manual ROI settings. To evaluate the validity of CT-ERPF, we examined the correlation of age with CT-ERPF and compared with reported ERPF values. We also compared the uptake rates of technetium-99m-dimercaptosuccinic acid and CT-ERPF in terms of the right-to-left ratio. Results: There was good agreement of CT-ERPF assessed using automatic and manual ROIs. CT-ERPF was negatively correlated with age and showed values below the reference ERPF range in 21 cases. The right-to-left ratio of CT-ERPF showed a significant correlation with that of technetium-99m-dimercaptosuccinic acid. Conclusions: Using our method, CT-ERPF was a useful indicator for preoperative evaluation of donor’s renal function.
- Published
- 2020
- Full Text
- View/download PDF
5. Two surgical cases of pneumothorax after treatment for COVID-19 pneumonia
- Author
-
Sotaro Otake, Julian Horiguchi, Toshinori Fukutomi, Takahiko Oyama, and Ryoichi Kato
- Subjects
General Medicine - Published
- 2023
6. A case of an inflammatory myofibroblastic tumor of the bladder in a young woman
- Author
-
Hokuto Akamatsu, Shimpei Akiyama, Ryoichi Kato, Hitoshi Ishise, Ryoichi Shiroki, Yuka Kiriyama, Makoto Kuroda, and Hiroshi Toyama
- Subjects
inflammatory myofibroblastic tumor ,urinary bladder ,inflammatory pseudotumor ,magnetic resonance imaging ,submucosal tumor ,Medicine (General) ,R5-920 - Abstract
We herein report a relatively rare case of an inflammatory myofibroblastic tumor (IMT) of the bladder in a young woman. In contrast to IMTs of other organs, IMTs of the lower urinary tract involve the mixture of a non-neoplastic lesion with a neoplastic lesion; therefore, the determination of whether other neoplastic lesions are present is important. In this case, magnetic resonance imaging confirmed a pedunculated lobulated tumor that protruded from the posterior left bladder wall into the lumen. The lobulated area exhibited a low-intensity signal on T1-weighted imaging (T1WI) and a high-intensity signal similar to that of urine on T2-weighted imaging (T2WI). Morphologically, the peduncle resembled a submucosal mass with faint low-intensity signaling on T1WI and faint high-intensity signaling on T2WI. These findings differ from those of a neoplastic lesion of the bladder mucous membrane. The presence of lesions from the muscularis propria to the submucosa and in areas with markedly high-intensity signals exhibiting a nodular fasciitis pattern on T2WI is considered useful for the differential diagnosis of IMT on imaging examination.
- Published
- 2017
- Full Text
- View/download PDF
7. A surgical case of congenital bronchial atresia communicating with an esophageal cyst with partial anomalous pulmonary venous return
- Author
-
Sotaro Otake, Takahiko Oyama, Toshinori Fukutomi, and Ryoichi Kato
- Published
- 2022
8. Gait analysis of total hip arthroplasty patients based on the spectral analysis results of trunk acceleration
- Author
-
Masahiro YONEDA, Mitsuhiko IKEBUCHI, Kanji FUKUDA, Ryoichi KATO, Tamotsu NAKATSUCHI, Shigeyoshi NAKAJIMA, and Hiroaki NAKAMURA
- Subjects
gait analysis ,total hip arthroplasty patients ,accelerometer ,fft analysis ,rehabilitation ,Mechanical engineering and machinery ,TJ1-1570 ,Engineering machinery, tools, and implements ,TA213-215 - Abstract
The purpose of this study is to investigate the gait improvement for patients after total hip arthroplasty (THA) by using accelerometers attached to the trunk of body before and after surgery (initial gait after THA, in hospital, at discharge, 3 months after THA, 6 months after THA, 1 year after THA). Thirty patients (mean age 61.1 ± 11.1 years old) were selected. Twelve healthy subjects (mean age 24.1 ± 2.6 years old) were also selected as a control group. Dynamic load factor (DLF) corresponding to the vertical walking force and lateral displacement of the trunk are calculated using power spectrum density for time history trunk signals measured by the accelerometers. The parameter PR in the fore and posterior directions is also obtained which is defined as the power spectrum ratio of 0.5fw to fw component where 0.5fw is half frequency component of the gait cycle fw. Based on these results, it was confirmed that the parameter PR in the fore and posterior directions, DLF in the vertical direction and lateral displacement of the trunk were the useful evaluation indices in order to evaluate the gait improvement for THA postoperative patients.
- Published
- 2019
- Full Text
- View/download PDF
9. A Case of Pseudoaneurysm of a Branch of the Dorsal Pancreatic Artery after Robotic Gastrectomy
- Author
-
Masahiro Fujita, Susumu Shibasaki, Kenichi Nakamura, Tsuyoshi Tanaka, Ryoichi Kato, Makoto Urano, Kazuki Inaba, Ichiro Uyama, and Koichi Suda
- Subjects
Gastroenterology ,Surgery - Published
- 2022
10. Successful thoracic duct identification with patent blue V during thoracic duct ligation for chylothorax: a case report
- Author
-
Yamato Suzuki, Koji Yamana, Hisato Ishizawa, Hiroshi Kawai, Yasushi Matsuda, Ryoichi Kato, Yasushi Takagi, and Yasushi Hoshikawa
- Abstract
Background Chylothorax after thoracic surgery is a rare but severe complication. When thoracic duct ligation is performed for chylothorax, identification of the leakage site and the thoracic duct course is necessary. Administering milk orally or through a nasogastric tube and injecting indocyanine green into lymph nodes and lymphatic vessels can be performed to identify the leakage site and the thoracic duct course. However, the injection of patent blue V into the inguinal lymph nodes has not been reported. Case presentation A 69-year-old man underwent aortic replacement surgery for an aortic aneurysm of the distal arch. On postoperative day 3, after resuming oral intake, the patient was diagnosed with chylothorax. The patient was treated with fasting and total parenteral nutrition, but the chylous pleural effusion continued at 500–1000 ml daily. A plan for thoracic duct ligation was made. We injected patent blue V into the inguinal lymph node to identify the leakage site and the thoracic duct course. The blue-stained thoracic duct was identified and ligated, but the leakage site could not be identified because of the surrounding lung adhesions. The thoracic drain was removed on day 6 post-second operation, and the chylothorax did not recur. Conclusion Identifying the thoracic duct course using patent blue V is useful during thoracic duct ligation for chylothorax.
- Published
- 2022
11. Urgent intraoperative endovascular stent placement to resolve acute hepatic or portal venous obstruction during liver surgery: a case series
- Author
-
Ryoichi Kato, Hiroyuki Nagata, Tatsuya Suzuki, Atsushi Sugioka, Akira Yasuda, Toshihiro Yasui, Yutaro Kato, Gozo Kiguchi, Junichi Yoshikawa, Masayuki Kojima, Ryota Hanaoka, Hokuto Akamatsu, Yoshinao Tanahashi, Ichiro Uyama, Yuichiro Uchida, and Sanae Nakajima
- Subjects
medicine.medical_specialty ,medicine.medical_treatment ,lcsh:Surgery ,Case Report ,Liver transplantation ,Anastomosis ,Endovascular stenting ,Hepatic vein ,03 medical and health sciences ,0302 clinical medicine ,Self-expandable metallic stent ,Biliary atresia ,Vascular reconstruction ,medicine ,Vein ,Interventional radiology ,medicine.diagnostic_test ,Liver resection ,business.industry ,lcsh:RD1-811 ,medicine.disease ,Venous Obstruction ,Surgery ,medicine.anatomical_structure ,030220 oncology & carcinogenesis ,Portal vein ,030211 gastroenterology & hepatology ,SEMS ,business ,Perfusion - Abstract
Background Acute obstruction of the hepatic vein (HV) or the portal vein (PV), particularly when it occurs during liver surgery, is potentially fatal unless repaired swiftly. As surgical interventions for this problem are technically demanding and potentially unsuccessful, other treatment options are needed. Case presentation We report two cases of acute, surgically uncorrectable HV or PV obstruction during liver resection or living donor liver transplantation (LDLT), which was successfully treated with urgent intraoperative placement of endovascular stents using interventional radiology (IVR). In Case 1, a patient with colonic liver metastases underwent a non-anatomic partial hepatectomy of the segments 4 and 8 with middle hepatic vein (MHV) resection. Additionally, the patient underwent an extended right posterior sectionectomy with right hepatic vein (RHV) resection for tumors involving RHV. Reconstruction of the MHV was needed to avoid HV congestion of the anterior section of the liver. The MHV was firstly reconstructed by an end-to-end anastomosis between the MHV and RHV resected stumps. However, the reconstruction failed to retain the HV outflow and the anterior section became congested. Serial trials of surgical revisions including re-anastomosis, vein graft interposition and vein graft patch-plasty on the anastomotic wall failed to recover the HV outflow. In Case 2, a pediatric patient with biliary atresia underwent an LDLT and developed an intractable PV obstruction during surgery. Re-anastomosis with vein graft interposition failed to restore the PV flow and elongated warm ischemic time became critical. In both cases, the misalignment in HV or PV reconstruction was likely to have caused flow obstruction, and various types of surgical interventions failed to recover the venous flow. In both cases, an urgent IVR-directed placement of self-expandable metallic stents (SEMS) restored the HV or PV perfusion quickly and effectively, and saved the patients from developing critical conditions. Furthermore, in Cases 1 and 2, the SEMS placed were patent for a sufficient period of time (32 and 44 months, respectively). Conclusions The IVR-directed, urgent, intraoperative endovascular stenting is a safe and efficient treatment tool that serves to resolve the potentially fatal acute HV or PV obstruction that occurs in the middle of liver surgery.
- Published
- 2021
12. Thoracoscopic surgery versus open surgery for lung metastases of colorectal cancer: a multi-institutional retrospective analysis using propensity score adjustment
- Author
-
Tomohiro, Murakawa, Hajime, Sato, Sakae, Okumura, Jun, Nakajima, Hirotoshi, Horio, Yuichi, Ozeki, Hisao, Asamura, Norihiko, Ikeda, Hajime, Otsuka, Haruhisa, Matsuguma, Ichiro, Yoshino, Masayuki, Chida, Mitsuo, Nakayama, Toshihiko, Iizasa, Meinoshin, Okumura, Satoshi, Shiono, Ryoichi, Kato, Tomohiko, Iida, Noriyuki, Matsutani, Masafumi, Kawamura, Yukinori, Sakao, Kazuhito, Funai, Go, Furuyashiki, Hirohiko, Akiyama, Shigeki, Sugiyama, Naoki, Kanauchi, Yuji, Shiraishi, Metastatic Lung Tumor Study Group of Japan, Tomohiro, Murakawa, Hajime, Sato, Sakae, Okumura, Jun, Nakajima, Hirotoshi, Horio, Yuichi, Ozeki, Hisao, Asamura, Norihiko, Ikeda, Hajime, Otsuka, Haruhisa, Matsuguma, Ichiro, Yoshino, Masayuki, Chida, Mitsuo, Nakayama, Toshihiko, Iizasa, Meinoshin, Okumura, Satoshi, Shiono, Ryoichi, Kato, Tomohiko, Iida, Noriyuki, Matsutani, Masafumi, Kawamura, Yukinori, Sakao, Kazuhito, Funai, Go, Furuyashiki, Hirohiko, Akiyama, Shigeki, Sugiyama, Naoki, Kanauchi, Yuji, Shiraishi, and Metastatic Lung Tumor Study Group of Japan
- Abstract
source:https://pubmed.ncbi.nlm.nih.gov/28329272
- Published
- 2022
13. Deep learning-based and hybrid-type iterative reconstructions for CT: comparison of capability for quantitative and qualitative image quality improvements and small vessel evaluation at dynamic CE-abdominal CT with ultra-high and standard resolutions
- Author
-
Yoshiharu Ohno, Yuya Ito, Ryo Matsukiyo, Hiroshi Toyama, Hiroyuki Nagata, Yukihiro Ogawa, Ryoichi Kato, Kazuhiro Murayama, Hirona Kimata, and Takahiro Matsuyama
- Subjects
Male ,Computer science ,Image quality ,Abdominal ct ,In Vitro Techniques ,Kidney ,030218 nuclear medicine & medical imaging ,03 medical and health sciences ,Deep Learning ,0302 clinical medicine ,Region of interest ,Abdomen ,Humans ,Radiology, Nuclear Medicine and imaging ,Carcinoma, Renal Cell ,business.industry ,Deep learning ,Hybrid type ,Arteries ,Middle Aged ,All arteries ,Quality Improvement ,Kidney Neoplasms ,030220 oncology & carcinogenesis ,Radiographic Image Interpretation, Computer-Assisted ,Female ,Artificial intelligence ,Small vessel ,Tomography, X-Ray Computed ,Nuclear medicine ,business ,Algorithms ,Student's t-test - Abstract
To determine the image quality improvement including vascular structures using deep learning reconstruction (DLR) for ultra-high-resolution CT (UHR-CT) and area-detector CT (ADCT) compared to a commercially available hybrid-iterative reconstruction (IR) method. Thirty-two patients suspected of renal cell carcinoma underwent dynamic contrast-enhanced (CE) CT using UHR-CT or ADCT systems. CT value and contrast-to-noise ratio (CNR) on each CT dataset were assessed with region of interest (ROI) measurements. For qualitative assessment of improvement for vascular structure visualization, each artery was assessed using a 5-point scale. To determine the utility of DLR, CT values and CNRs were compared among all UHR-CT data by means of ANOVA followed by Bonferroni post hoc test, and same values on ADCT data were also compared between hybrid IR and DLR methods by paired t test. For all arteries except the aorta, the CT value and CNR of the DLR method were significantly higher compared to those of the hybrid-type IR method in both CT systems reconstructed as 512 or 1024 matrixes (p
- Published
- 2020
14. A Case of Lung Adenocarcinoma with Myocardial Metastasis
- Author
-
Takahiko Oyama, Hiroaki Murakami, and Ryoichi Kato
- Subjects
Pulmonary and Respiratory Medicine ,Lung ,medicine.anatomical_structure ,Oncology ,business.industry ,medicine ,Cancer research ,Adenocarcinoma ,medicine.disease ,business ,Metastasis - Published
- 2020
15. Prostatic Metastasis of Pulmonary Large Cell Neuroendocrine Carcinoma
- Author
-
Kumi Shimizu, Taichiro Goto, Arafumi Maeshima, Yoshitaka Oyamada, Ryoichi Kato
- Subjects
Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Lung cancer metastases to the prostate are uncommon, and are usually found incidentally during autopsy. This case report describes a 77-year-old man with a large cell neuroendocrine carcinoma (LCNEC) of the lung and metastases from this primary cancer in the prostate. During the follow-up after the chemotherapy performed for pulmonary LCNEC, pelvic computed tomography revealed a prostatic tumor and prostatic needle biopsy was performed. Histologically, the tumor was identified as LCNEC, forming a tissue architecture closely resembling the previously diagnosed lung cancer. The tumor cells were immunohistochemically positive for thyroid transcription factor-1. These findings led to a diagnosis of prostatic metastasis of pulmonary LCNEC.
- Published
- 2012
16. Cavitary Lung Cancer Lined with Normal Bronchial Epithelium and Cancer Cells
- Author
-
Taichiro Goto, Arafumi Maeshima, Yoshitaka Oyamada, Ryoichi Kato
- Subjects
Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Reports of cavitary lung cancer are not uncommon, and the cavity generally contains either dilated bronchi or cancer cells. Recently, we encountered a surgical case of cavitary lung cancer whose cavity tended to enlarge during long-term follow-up, and was found to be lined with normal bronchial epithelium and adenocarcinoma cells.
- Published
- 2011
17. Substring search and repeat search using factor oracles.
- Author
-
Ryoichi Kato and Osamu Watanabe 0001
- Published
- 2005
- Full Text
- View/download PDF
18. Efficacy of Early Rehabilitation for Severe Coronavirus Disease 2019 Pneumonia: Factor Analysis Using Machine Learning.
- Author
-
Mitsuhiko Ikebuchi, Yoichi Ohta, Yukihide Minoda, Akiko Toki, Tamotsu Nakatsuchi, Hidetomi Terai, Hiroaki Nakamura, Ryoichi Kato, and Sigeyoshi Nakajima
- Published
- 2023
- Full Text
- View/download PDF
19. Relationships of design parameters and the cooling performance of the spiral-fin heatsink
- Author
-
Victor Parque, Muhammad Khairi Faiz, Motohito Hori, Ryoichi Kato, Shingo Otake, Tomoyuki Miyashita, Makoto Yoshida, and Yoshinari Ikeda
- Subjects
Fin ,Materials science ,ComputerSystemsOrganization_COMPUTERSYSTEMIMPLEMENTATION ,Power module ,Data_FILES ,Miniaturization ,Mechanical engineering ,Physics::Atomic Physics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Spiral (railway) ,Heat sink ,ComputingMilieux_MISCELLANEOUS ,Astrophysics::Galaxy Astrophysics - Abstract
Due to the demand for miniaturization, further improvement in cooling performance is required for power modules. The spiral-fin heatsink we considered has higher cooling performance than conventional ones. In this paper, we examined the design parameters of the spiral-fin, and found that three parameters of spiral-fin have big effect for the Cooling performance.
- Published
- 2021
20. Design optimization of copper patterns and location of power semiconductors and terminals
- Author
-
Akira Hirao, Muhammad Khairi Faiz, Yoshinari Ikeda, Tomoyuki Miyashita, Makoto Yoshida, Victor Parque, Ryoichi Kato, and Yusuke Abe
- Subjects
Electromagnetic field ,Materials science ,Silicon ,Page layout ,business.industry ,Electrical engineering ,chemistry.chemical_element ,computer.software_genre ,Inductance ,chemistry.chemical_compound ,chemistry ,Power module ,Silicon carbide ,Power semiconductor device ,Lead (electronics) ,business ,computer - Abstract
In recent years, SiC power modules have attracted a lot of attention because they offer higher frequency and density as compared to the conventional Si power module. However high speed switching inevitably lead to the generation of surge voltage which may damage the power module. The design of layout, which composed of copper patterns, power semiconductors and terminals, is one of the factors that is necessary to overcome the problem. In this paper, the layout design of the half-bridge power module is optimized to reduce its internal inductance. The inductance was evaluated by electromagnetic field simulation.
- Published
- 2021
21. An Adult Case of Pulmonary Artery Sling Accompanied by Tracheobronchomalacia
- Author
-
Kazuma Yagi, Sahoko Imoto, Kazuyuki Fujimoto, Sota Oguro, Mayuko Watase, Sakiko Hosoo, Ryosuke Satomi, Hiroaki Murakami, Ryoichi Kato, Iio Miwa, Yoshitaka Oyamada, Shigenari Nukaga, Takahiko Oyama, and Matsuo So
- Subjects
medicine.medical_specialty ,Sling (implant) ,Case Report ,Bronchi ,Constriction, Pathologic ,Opportunistic Infections ,Pulmonary Artery ,Bronchoscopy ,medicine.artery ,Internal Medicine ,medicine ,Humans ,Abnormalities, Multiple ,Achondroplasia ,tracheobronchomalacia ,medicine.diagnostic_test ,business.industry ,recurrent lung infections ,Adult case ,Pneumonia ,General Medicine ,Middle Aged ,Pulmonary artery sling ,medicine.disease ,Surgery ,pulmonary artery sling ,Stenosis ,Tracheobronchomalacia ,Pulmonary artery ,Female ,Tomography, X-Ray Computed ,Tracheal Stenosis ,business - Abstract
Pulmonary artery (PA) sling is a congenital disease in which the left PA abnormally arises from the right PA and is usually diagnosed during the infantile period. We present an adult case of PA sling accompanied by tracheobronchomalacia found in a 49-year-old woman with a history of recurrent pneumonia. Computed tomography of the chest showed that the left lung was nourished by two aberrant PAs. Bronchoscopy demonstrated achondroplasia of the trachea and the right bronchus, which we speculate to have resulted in their stenosis. The recurrent pneumonia was attributable to these tracheobronchial structural abnormalities; we therefore stress the importance of focusing on the anatomic abnormalities in such cases.
- Published
- 2019
22. Gait analysis of total hip arthroplasty patients based on the spectral analysis results of trunk acceleration
- Author
-
Tamotsu Nakatsuchi, Masahiro Yoneda, Hiroaki Nakamura, Kanji Fukuda, Ryoichi Kato, Mitsuhiko Ikebuchi, and Shigeyoshi Nakajima
- Subjects
medicine.medical_specialty ,Acceleration ,Physical medicine and rehabilitation ,business.industry ,Gait analysis ,Medicine ,Spectral analysis ,business ,Trunk ,Total hip arthroplasty - Published
- 2019
23. A Bayesian approach to diffusional kurtosis imaging
- Author
-
Eizou Umezawa, Ryoichi Kato, and Daichi Ishihara
- Subjects
Computer science ,Gaussian ,Bayesian probability ,Overfitting ,Bayesian inference ,Regularization (mathematics) ,030218 nuclear medicine & medical imaging ,03 medical and health sciences ,symbols.namesake ,0302 clinical medicine ,Prior probability ,Humans ,Radiology, Nuclear Medicine and imaging ,business.industry ,Pattern recognition ,Bayes Theorem ,Glioma ,Diffusion Magnetic Resonance Imaging ,Diffusion Tensor Imaging ,ROC Curve ,Metric (mathematics) ,Kurtosis ,symbols ,Artificial intelligence ,business ,030217 neurology & neurosurgery - Abstract
Purpose Diffusional kurtosis metrics show high performance for detecting pathological changes and are therefore expected to be disease biomarkers. Kurtosis maps, however, tend to be noisy. The maps' visual quality is crucial for disease diagnosis, even when kurtosis is being used quantitatively. A Bayesian method was proposed to curtail the large statistical error inherent in kurtosis estimation while maintaining potential application to biomarkers. Theory Gaussian priors are determined from first-step estimations implemented using the least-square method (LSM). The likelihood-function variance is determined from the residuals of the estimation. Although the proposed approach is similar to a regularized LSM, regularization parameters do not have to be artificially adjusted. An appropriate balance between denoising and preventing false shrinkages of metric dispersions is automatically achieved. Methods Map qualities achieved using the conventional and proposed methods were compared. The receiver-operating characteristic analysis was performed for glioma-grade differentiation using simulated low- and high-grade glioma DWI datasets. Noninferiority of the proposed method was tested for areas under the curves (AUCs). Results The noisier the conventional maps, the better the proposed Bayesian method improved them. Noninferiority of the proposed method was confirmed by AUC tests for all kurtosis-related metrics. Superiority of the proposed method was also established for several metrics. Conclusions The proposed approach improved noisy kurtosis maps while maintaining their performances as biomarkers without increasing data acquisition requirements or arbitrarily choosing LSM regularization parameters. This approach may enable the use of higher-order terms in diffusional kurtosis imaging (DKI) fitting functions by suppressing overfitting, thereby improving the DKI-estimation accuracy.
- Published
- 2021
24. A massive cavitary lesion invading the chest wall
- Author
-
Takanori Asakura, Yohei Funatsu, Takahiko Oyama, Katsutaka Mineura, Arafumi Maeshima, Takashi Okabe, Hironori Ueno, Takahiro Yano, Yoshitaka Oyamada, and Ryoichi Kato
- Subjects
Infectious and parasitic diseases ,RC109-216 - Published
- 2015
- Full Text
- View/download PDF
25. Development and proof of concept of an immersive virtual reality system to evaluate near and far space neglect in individuals after stroke: A brief report
- Author
-
Shuntaro Kawaguchi, Hiroyasu Iwata, Kazuhiro Yasuda, Rikushi Sabu, and Ryoichi Kato
- Subjects
Male ,030506 rehabilitation ,Computer science ,media_common.quotation_subject ,Physical Therapy, Sports Therapy and Rehabilitation ,Space (commercial competition) ,Virtual reality ,Neuropsychological Tests ,Three-dimensional space ,Functional Laterality ,Neglect ,Task (project management) ,Perceptual Disorders ,03 medical and health sciences ,0302 clinical medicine ,Development (topology) ,Human–computer interaction ,Humans ,media_common ,Aged ,Rehabilitation ,Virtual Reality ,Near space ,Stroke ,Proof of concept ,Space Perception ,Female ,Neurology (clinical) ,0305 other medical science ,030217 neurology & neurosurgery - Abstract
Background Unilateral spatial neglect (USN) is defined as impaired attention to sensory stimuli on one side. The symptoms can exist for near and far spaces combined or independently. Thus, it is important to evaluate both possibilities in a clinical environment. Objective To develop a tractable immersive virtual reality (iVR) system that can evaluate both near and far space neglect along with a proof of concept study to determine whether near and far spatial neglect could be described in an actual patient with USN. Methods An object-detecting task was developed in a three-dimensional virtual reality space. The examiner recorded the positional data of objects that were recognized by the patient with USN using coordinate data. Results The system could be used to detect near and far space neglects in a patient with USN. No side effects such as vertigo were seen during measurement. This patient showed that the angle for recognition was significantly larger for near space than far space, and exhibited a tendency for the angle of recognition to increase with lower height. Conclusions Our proof of concept study indicated the possibility of applying an evaluation system that separates far and near space neglect using iVR.
- Published
- 2020
26. [Acute Necrotizing Esophagitis Occurred after Lung Resection for Lung Cancer]
- Author
-
Yasoo, Sugiura, Seiho, Gochou, Yoshihiko, Sakurai, Hiroyuki, Fujimoto, Ryoichi, Kato, Etsuo, Nemoto, and Toshinori, Hashizume
- Subjects
Male ,Necrosis ,Lung Neoplasms ,Acute Disease ,Esophagitis ,Humans ,Neoplasm Recurrence, Local ,Pneumonectomy ,Aged - Abstract
The patient was a 78-year-old man who had undergone left lung segmentectomy (S6) with lymph node dissection for lung adenocarcinoma. One year and 5 months later, lung partial resection was performed for the lung cancer recurrence and the hematemesis was noted on the next day of surgery. Upper gastrointestinal endoscopy revealed extensive black necrosis on the mucosa of the esophagus, which was diagnosed as acute necrotizing esophagitis. To treat the bleeding, the exposed esophageal vessels were clipped via endoscopy several times. The endoscopy on the 64th post-operative day showed the mucosa recovered and he could be discharged on the 85th day. The exact etiology of acute necrotizing esophagitis is unknown in most cases.
- Published
- 2020
27. A case report of pulmonary Mycobacterium xenopi infection suspected as lung cancer
- Author
-
Ryoichi Kato, Takahiko Oyama, and Hiroaki Murakami
- Subjects
Pathology ,medicine.medical_specialty ,biology ,business.industry ,biology.organism_classification ,medicine.disease ,03 medical and health sciences ,0302 clinical medicine ,030228 respiratory system ,medicine ,030212 general & internal medicine ,Mycobacterium xenopi ,business ,Lung cancer - Published
- 2018
28. Thoracoscopic surgery versus open surgery for lung metastases of colorectal cancer: a multi-institutional retrospective analysis using propensity score adjustment
- Author
-
Tomohiro, Murakawa, Hajime, Sato, Sakae, Okumura, Jun, Nakajima, Hirotoshi, Horio, Yuichi, Ozeki, Hisao, Asamura, Norihiko, Ikeda, Hajime, Otsuka, Haruhisa, Matsuguma, Ichiro, Yoshino, Masayuki, Chida, Mitsuo, Nakayama, Toshihiko, Iizasa, Meinoshin, Okumura, Satoshi, Shiono, Ryoichi, Kato, Tomohiko, Iida, Noriyuki, Matsutani, Masafumi, Kawamura, Yukinori, Sakao, Kazuhito, Funai, Go, Furuyashiki, Hirohiko, Akiyama, Shigeki, Sugiyama, Naoki, Kanauchi, Yuji, Shiraishi, and Metastatic Lung Tumor Study Group of Japan
- Subjects
Pulmonary and Respiratory Medicine ,Male ,medicine.medical_specialty ,Lung Neoplasms ,medicine.medical_treatment ,030204 cardiovascular system & hematology ,03 medical and health sciences ,0302 clinical medicine ,medicine ,Thoracoscopy ,Humans ,Thoracotomy ,Pneumonectomy ,Propensity Score ,Survival rate ,Aged ,Retrospective Studies ,medicine.diagnostic_test ,Proportional hazards model ,business.industry ,Hazard ratio ,General Medicine ,Middle Aged ,Surgery ,Log-rank test ,030220 oncology & carcinogenesis ,Propensity score matching ,Female ,Metastasectomy ,Cardiology and Cardiovascular Medicine ,business ,Colorectal Neoplasms - Abstract
Objectives Thoracoscopic surgery for lung metastasectomy remains controversial. The study aimed at determining the efficacy of thoracoscopic surgery for lung metastasectomy. Methods This was a multi-institutional, retrospective study that included 1047 patients who underwent lung metastasectomy for colorectal cancer between 1999 and 2014. Prognostic factors of overall survival were compared between the thoracoscopic and open thoracotomy groups using the multivariate Cox proportional hazard model. The propensity score, calculated using the preoperative covariates, included the era of lung surgery as a covariate. A stepwise backward elimination method, with a probability level of 0.15, was used to select the most powerful sets of outcome predictors. The difference between the radiological tumour number and the resected tumour number (delta_num) was also evaluated. Results The c -statistics and the P -value of the Hosmer-Lemeshow Chi-square of the propensity score model were 0.7149 and 0.1579, respectively. After adjusting for the propensity score, the thoracoscopy group had a better survival rate than the open group (stratified log-rank test: P = 0.0353). After adjusting for the propensity score, the most powerful predictive model for overall survival was that which combined thoracoscopy [hazard ratio (HR): 0.468, 95% CI: 0.262-0.838, P = 0.011] and anatomical resection (HR: 1.49, 95% CI: 1.134-1.953, P = 0.004). Before adjusting for the propensity score, the delta_num was significantly greater in the open group than in the thoracoscopy group (thoracoscopy: 0.06, open: 0.33, P = 0.001); however, after adjustment, there was no difference in the delta_num (thoracoscopy: 0.04, open: 0.19, P = 0.114). Conclusions Thoracoscopic metastasectomy showed better overall survival than the open approach in this analysis. The thoracoscopic approach may be an acceptable option for resection of pulmonary metastases in terms of tumour identification and survival outcome in the current era.
- Published
- 2017
29. [Metastatic Lung Tumor from Papillary Thyroid Carcinoma Suspected of Primary Lung Cancer;Report of Two Cases]
- Author
-
Hiroaki, Murakami, Takahiko, Oyama, and Ryoichi, Kato
- Subjects
Male ,Lung Neoplasms ,Thyroid Cancer, Papillary ,Humans ,Female ,Thyroid Neoplasms ,Middle Aged ,Neoplasm Recurrence, Local ,Lung ,Aged - Abstract
Radiological finding of pulmonary metastasis of thyroid cancer is generally known to be multiple small nodular shadow. We experienced 2 cases of lung solitary tumor, which were suspected of primary lung cancer as differential diagnosis. Patient 1:A 67-year-old man;the tumor obstructed subsegmental bronchus (B10) of the right lobe, and pathological diagnosis by transbronchial biopsy was adeno-squamous carcinoma. Fluoro-2-deoxy-D-glucose (FDG) positron emission tomography (PET) showed abnormal uptake in the tumor and also in the left lobe of his thyroid gland, but no malignant findings were found by the fine-needle aspiration cytology from the thyroid gland. Patient 2:A 51-year-old woman;she had a lobulated nodule in the left lower lobe, which was diagnosed as adenocarcinoma. She had undergone an operation for thyroid cancer about 30 years earlier, but after the operation, there has been no recurrence. In both cases, primary lung cancer were suspected and the tumors were resected surgically. By immunohistochemistry, both tumors were diagnosed as pulmonary metastases from papillary thyroid carcinoma.
- Published
- 2019
30. Heatsink design using spiral-fins considering additive manufacturing
- Author
-
Yoshihiro Tateishi, Tomoyuki Miyashita, Ryoichi Kato, Muhammed Khairi Faiz, Shingo Otake, Makoto Yoshida, Victor Parque, Hiromichi Gohara, and Yoshinari Ikeda
- Subjects
Pressure drop ,Fin ,Materials science ,Power module ,Thermal resistance ,Miniaturization ,Mechanical engineering ,Dissipation ,Heat sink ,Spiral - Abstract
In recent years, there have been increasing the number of power modules which is required with high performance, miniaturization and weight saving. But these requires cause high heat generation density for power module, which gets junction operation temperature to rise. Cooling unit is thus greatly demanded for high heat dissipation. The simple shaped heatsinks (straight-fin type and pin fin type) were generally used. But they have the limit of cooling performance. In this report, we have developed new heatsink shape to cope with rapidly increasing of the cooling requirement. Cooling performance is shown to thermal resistance and pressure loss. We evaluated them by thermal fluid analysis. In this approach, the spiral-fin heatsink with spiral curved channels has excellent cooling performance. This shape is the unique point in this report. This is because the shape with three-dimensional regular curve has not been studied. The spiral-fin heatsink has many factors (fin thickness, fin pitch, the number of channels, etc.). These factors affect cooler performance. We changed these factors to determine the best shape of spiral-fin. As a result, the best shape is 14.9[%] lower than the straight-fin type in thermal resistance.
- Published
- 2019
31. Gene Expression of Semaphorin 7A During Osteogenic Differentiation in Human Dental Follicle Cells
- Author
-
Kosuke Takahashi and Ryoichi Kato
- Subjects
0301 basic medicine ,Dental follicle ,Medicine (miscellaneous) ,Cell Biology ,Biology ,Biochemistry ,Cell biology ,Biomaterials ,03 medical and health sciences ,030104 developmental biology ,Semaphorin ,Gene expression ,Orthopedics and Sports Medicine ,Stem cell ,General Dentistry - Published
- 2016
32. On Design Optimization of Heat Sinks with Curvature Considerations for Additive Manufacturing
- Author
-
Muhammad Khairi Faiz, Victor Parque, Yoshihiro Tateishi, Ryoichi Kato, Tomoyuki Miyashita, Makoto Yoshida, Yoshinari Ikeda, and Hiromichi Gohara
- Subjects
Fin ,Machining ,Computer science ,Power module ,Thermal resistance ,Design of experiments ,Mechanical engineering ,Point (geometry) ,Heat sink ,Finite element method - Abstract
As recent power modules with utmost performance are required in small and light-weight structures, the design and the manufacturing of heat sinks that offer maximal cooling performance have become a challenge due to continuously evolving miniaturization and smaller cooling areas. In line of the above, and for practical realizations, heat sinks having the ability to operate in limited volume, as well as having simple geometry are highly desirable due to existing limitations in cooling area and machining processes. We propose a methodology to design heat sinks that aim at minimizing temperature and pressure loss based on fin considerations, as well as design of experiments and response surfaces of objective functions about design variables. Numerical simulations and sensitivity analyses based on Finite Element Method have shown the improved cooling performance in terms of thermal resistance when compared to the conventional heat sinks with straight fins. The unique point of our proposed approach lies not only in the simplicity of the geometry of the heat sink, but also in the higher cooling performance, which is key to realize enhanced cooling mechanisms by existing metal-based 3D printers. We believe our approach offers the building blocks to enable the design and realization of heat sinks with manufacturable geometry and utmost cooling performance. As such, our proposed approach has the potential to capitalize on the benefits of metal-based 3D printing technologies, enabling the possibility to realize challenging geometries.
- Published
- 2018
33. Intratumoral gene expression of 5-fluorouracil pharmacokinetics-related enzymes in stage I and II non-small cell lung cancer patients treated with uracil-tegafur after surgery: A prospective multi-institutional study in Japan
- Author
-
Mitsuo Nakayama, Koichi Kobayashi, Atsushi Tajima, Takahiko Oyama, Masafumi Kawamura, Hirotoshi Horio, Toshinori Hashizume, Noriyuki Matsutani, Ryoichi Kato, Keisuke Eguchi, Tomohiro Abiko, and Makoto Sawafuji
- Subjects
Adult ,Male ,Pulmonary and Respiratory Medicine ,Oncology ,Antimetabolites, Antineoplastic ,Cancer Research ,medicine.medical_specialty ,Lung Neoplasms ,Adenocarcinoma ,Thymidylate synthase ,Gene Expression Regulation, Enzymologic ,Japan ,Risk Factors ,Carcinoma, Non-Small-Cell Lung ,Internal medicine ,medicine ,Dihydropyrimidine dehydrogenase ,Humans ,Prospective Studies ,Thymidine phosphorylase ,Lung cancer ,Aged ,Neoplasm Staging ,Tegafur ,Aged, 80 and over ,biology ,business.industry ,Middle Aged ,medicine.disease ,Surgery ,Gene Expression Regulation, Neoplastic ,Treatment Outcome ,Real-time polymerase chain reaction ,Fluorouracil ,Carcinoma, Squamous Cell ,biology.protein ,Orotate phosphoribosyltransferase ,Female ,business ,medicine.drug - Abstract
Objectives This investigation was conducted to assess the use of the intratumoral mRNA expression levels of nucleic acid-metabolizing enzymes as biomarkers of adjuvant chemotherapy for non-small cell lung cancer (NSCLC) using uracil-tegafur in a multi-institutional prospective study. Materials and methods 236 patients with a completely resected NSCLC (adenocarcinoma and squamous cell carcinoma) of pathological stage IA (maximum tumor diameter of 2 cm or greater), IB, and II tumors were given a dose of 250 mg of uracil-tegafur per square meter of body surface area per day orally for two years after surgery. Intratumoral mRNA levels of thymidylate synthase (TS), dihydropyrimidine dehydrogenase (DPD), orotate phosphoribosyltransferase (OPRT), and thymidine phosphorylase (TP) genes relative to an internal standard, β-actin, were determined using laser-capture microdissection and fluorescence-based real time PCR detection systems. Results and conclusion Among 5-FU target enzymes, TS was the only one that showed a significant difference in the level of gene expression between the high and low gene expression groups, for both disease-free survival (DFS) and overall survival (OS), when patients were divided according to median values; 5-year DFS rates in high/low TS gene expression were 60.4% and 72.6%, respectively (p = 0.050), 5-year OS rates were 78.1% and 88.6%, respectively (p = 0.011). Cox's proportional hazard model indicated that the pathological stage and TS gene expression level were independent values for predicting DFS. The TS gene expression level was shown to be an independent predictive factor for DFS in stage I and II NSCLC patients who were treated with uracil-tegafur following surgery.
- Published
- 2015
34. Hemodynamic-based Mapping of Neural Activity in Medetomidine-sedated Rats using a 1.5T Compact Magnetic Resonance Imaging System: A Preliminary Study
- Author
-
Ryoichi Kato, Masayuki Yamada, Yuki Kawai, and Kazuki Takano
- Subjects
Haemodynamic response ,Hemodynamics ,Stimulation ,Somatosensory system ,Neuroimaging ,Animals ,Hypnotics and Sedatives ,Medicine ,Radiology, Nuclear Medicine and imaging ,Rats, Wistar ,medicine.diagnostic_test ,business.industry ,Magnetic resonance imaging ,Somatosensory Cortex ,Medetomidine ,Magnetic Resonance Imaging ,Functional magnetic resonance spectroscopy of the brain ,Electric Stimulation ,Rats ,Anesthesia ,Female ,business ,Biomedical engineering ,medicine.drug - Abstract
The use of compact magnetic resonance (MR) systems for the neuroimaging of small animals is spreading. We investigated the potential of such systems in functional MR imaging (fMRI) of somatosensory cortex activity elicited by forepaw stimulation in medetomidine-sedated rats. Using a 1.5-tesla compact imager, we detected maximum activity with an electrophysiologically optimized frequency of 9 Hz in 3 appropriately sedated rats. With this compact system, we successfully mapped neural activity by combining optimum stimulation for a large hemodynamic response with appropriate anesthesia, thus demonstrating the utility of such systems in hemodynamic-based fMRI in preclinical and translational research.
- Published
- 2015
35. Efficacy and Safety of Percutaneous Transhepatic Portal Embolization with Dehydrated Ethanol
- Author
-
Ryota Hanaoka, Ryoichi Kato, Tatsuo Banno, Hiroshi Toyama, and Hokuto Akamatsu
- Subjects
medicine.medical_specialty ,Percutaneous ,business.industry ,medicine.medical_treatment ,Liver volume ,medicine.disease ,Surgery ,Liver Lobe ,Balloon occlusion ,medicine ,Lipiodol ,Radiology, Nuclear Medicine and imaging ,Embolization ,Hepatectomy ,business ,Liver cancer ,medicine.drug - Abstract
Purpose: The efficacy and safety of percutaneous transhepatic portal embolization (PTPE) with dehydrated ethanol was determined by measuring the liver lobe volume before and after the procedure. Materials and Methods: A total of 38 patients (25 men, 13 women; mean age: 62.0 ± 10.8 years) who underwent PTPE with dehydrated ethanol between April 2005 and March 2011 participated in this study. Dehydrated ethanol containing 17% lipiodol was injected into the target portal vein branch under balloon occlusion, and the portal vein was subsequently embolized. The liver lobe volume was measured via contrast-enhanced computed tomography, and the percent increase in the unembolized lobe volume was then calculated. In addition, PTPE-related complications were surveyed, and the procedural safety was evaluated. Results: The mean percent increase in the unembolized lobe volume after PTPE was 33.8% ± 20.2%. The procedure could not be completed in one patient because of an insufficient increase in the unembolized lobe volume. No serious post- PTPE complications were observed. Conclusion: These data suggest that PTPE with dehydrated ethanol is a safe and effective method for enlarging the planned residual liver volume before extensive liver resection.
- Published
- 2014
36. SWALLOWING COMPUTED TOMOGRAPHY: DOSE ESTIMATION IN A PHANTOM STUDY CONDUCTED AT VARIOUS PATIENT RECLINING ANGLES
- Author
-
Hiroshi Toyama, Masanao Kobayashi, Tomihiko Daioku, Yuta Matsunaga, Tomonobu Haba, Shouichi Suzuki, Kazuyuki Minami, Ai Kawaguchi, Ryoichi Kato, Yasuki Asada, and Kosuke Matsubara
- Subjects
medicine.medical_specialty ,viruses ,Patient positioning ,Computed tomography ,Radiation Dosage ,Effective dose (radiation) ,Imaging phantom ,Patient Positioning ,030218 nuclear medicine & medical imaging ,030507 speech-language pathology & audiology ,03 medical and health sciences ,0302 clinical medicine ,Swallowing ,Dose estimation ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Radiation ,Radiological and Ultrasound Technology ,medicine.diagnostic_test ,business.industry ,Phantoms, Imaging ,Public Health, Environmental and Occupational Health ,General Medicine ,Deglutition ,Tomography x ray computed ,Patient dose ,Thermoluminescent Dosimetry ,Radiology ,0305 other medical science ,Nuclear medicine ,business ,Tomography, X-Ray Computed - Abstract
Swallowing computed tomography (SCT) is a relatively new technique for the morphological and kinematic analyses of swallowing. However, no optimal scan protocols are available till date. We conducted the present SCT study to estimate the patient dose at various patient reclining positions. A RANDO phantom with a thermoluminescent dosemeter was placed on a hard Table board in a semi-reclining position at the centre and off-centre. According to predetermined scan protocols, irradiation was performed to acquire scanograms at reclining angles of 55° and 65°. The effective dose was the lowest at the centre 45° (3.8 mSv) reclining angle. Comparison between the off-centre (4.6 mSv at 55°, 6.8 mSv at 65°) and centre (4.5 mSv, 5.8 mSv) values suggested that the off-centre position is undesirable with regard to the patient dose. Accordingly, we believe that SCT methods must be revised on the basis of these factors.
- Published
- 2017
37. Technical Tips for Endovascular Aortic Repair Using the Gore Excluder Abdominal Stent-Graft: Endo-Wedge Technique and Scrum Technique
- Author
-
Ryoichi Kato, Hiroshi Toyama, Hokuto Akamatsu, Kan Kaneko, Ryota Hanaoka, and Tatsuo Banno
- Subjects
medicine.medical_specialty ,business.product_category ,business.industry ,medicine.medical_treatment ,medicine ,Stent ,Radiology, Nuclear Medicine and imaging ,Radiology ,business ,Aortic repair ,Wedge (mechanical device) ,Surgery - Abstract
When performing endovascular aortic repair (EVAR) procedures, clinicians sometimes encounter cases in which the indications for EVAR are beyond the instruction for use (IFU). In EVAR, proximal neck fixation is the most important factor. This report describes several techniques and tips for EVAR in cases presenting with a difficult short neck or angled neck, especially when using the Gore Excluder®. Endo-wedge techniques (EWT), including non-sheath-assisted EWT with sheath-assisted strategies, are presented. We describe the scrum technique, which is a special procedure that is only feasible when using the Gore Excluder®. In this technique, intentional wire bending around the proximal neck portion occurs by pushing from both sides of the guidewire. This technique is applicable in cases with a sharply angled neck. The scrum with EWT is a more precise strategy for cases with a short or angled neck. Other troublesome cases include limb occlusion caused by weak points in the Gore Excluder® body and legs. The very rare complication of stent-graft collapse is also reviewed.
- Published
- 2014
38. A case of needle track recurrence of lung cancer after CT-guided percutaneous needle biopsy
- Author
-
Katsutaka Mineura, Kumi Akanabe, Ryoichi Kato, and Takahiko Oyama
- Subjects
Needle track ,medicine.medical_specialty ,Percutaneous needle biopsy ,business.industry ,medicine ,Radiology ,Lung cancer ,medicine.disease ,business - Published
- 2014
39. Idiopathic pulmonary fibrosis as a prognostic factor in non-small cell lung cancer
- Author
-
Ryoichi Kato, Yoshitaka Oyamada, Taichiro Goto, and Arafumi Maeshima
- Subjects
Male ,Oncology ,medicine.medical_specialty ,Prognostic factor ,Lung Neoplasms ,Idiopathic pulmonary fibrosis ,Surgical oncology ,Carcinoma, Non-Small-Cell Lung ,Internal medicine ,Carcinoma ,medicine ,Humans ,Lung cancer ,Aged ,Neoplasm Staging ,Emphysema ,Hyperplasia ,business.industry ,Hematology ,General Medicine ,Middle Aged ,respiratory system ,Prognosis ,medicine.disease ,Idiopathic Pulmonary Fibrosis ,respiratory tract diseases ,Postoperative mortality ,Female ,Surgery ,Non small cell ,business - Abstract
We investigated the postoperative mortality and long-term survival of lung cancer patients with underlying idiopathic pulmonary fibrosis (IPF).The data of 387 primary lung cancer patients treated by surgical resection at our hospital between 1995 and 2008 were retrospectively reviewed. Clinicopathological characteristics such as age, gender, survival, presence/absence of underlying IPF, atypical adenomatous hyperplasia (AAH), and the associations among these factors were examined.Among the 387 patients, 65 (16.8 %) had underlying IPF as detected by histopathology of the resected specimen (IPF group). The percentages of men and squamous cell carcinomas were significantly higher in the IPF group. None of our patients showed concomitant presence of AAH and IPF. Four of the 65 patients showed acute exacerbation of the IPF postoperatively, and all 4 of these patients died in hospital. In patients with non-small cell lung carcinoma, the postoperative survival tended to be lower in the IPF group than in the non-IPF group. Analysis using a Cox proportional hazards model by disease stage revealed that presence of underlying IPF was a risk factor for postoperative mortality in patients with pathological stage I/II but not for stage III/IV. Respiratory failure was the second main cause of death in the stage I/II lung cancer patients of the IPF group.Histopathological evidence of IPF was a risk factor for postoperative mortality and poor long-term survival, especially in patients with stage I/II non-small cell lung cancer, with postoperative respiratory failure representing the major cause of death.
- Published
- 2013
40. Dose Estimating Application Software Modification: Additional Function of a Size-Specific Effective Dose Calculator and Auto Exposure Control
- Author
-
Yasuki Asada, Shouichi Suzuki, Masanao Kobayashi, Hiroshi Toyama, Ryoichi Kato, Tomonobu Haba, Ai Kawaguchi, Kosuke Matsubara, Yuta Matsunaga, and Tomihiko Daioku
- Subjects
Computer science ,Computed tomography ,Radiation Dosage ,Application software ,computer.software_genre ,Effective dose (radiation) ,030218 nuclear medicine & medical imaging ,law.invention ,Toxicology ,03 medical and health sciences ,0302 clinical medicine ,Software ,law ,Dose estimation ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Exposure control ,Radiometry ,Task group ,Radiation ,Radiological and Ultrasound Technology ,medicine.diagnostic_test ,Phantoms, Imaging ,business.industry ,Public Health, Environmental and Occupational Health ,General Medicine ,Reliability engineering ,Calculator ,030220 oncology & carcinogenesis ,Tomography, X-Ray Computed ,business ,computer - Abstract
Adequate dose management during computed tomography is important. In the present study, the dosimetric application software ImPACT was added to a functional calculator of the size-specific dose estimate and was part of the scan settings for the auto exposure control (AEC) technique. This study aimed to assess the practicality and accuracy of the modified ImPACT software for dose estimation. We compared the conversion factors identified by the software with the values reported by the American Association of Physicists in Medicine Task Group 204, and we noted similar results. Moreover, doses were calculated with the AEC technique and a fixed-tube current of 200 mA for the chest-pelvis region. The modified ImPACT software could estimate each organ dose, which was based on the modulated tube current. The ability to perform beneficial modifications indicates the flexibility of the ImPACT software. The ImPACT software can be further modified for estimation of other doses.
- Published
- 2016
41. Pulmonary Resection for Mycobacterium Chelonae Infection
- Author
-
Yoshitaka Oyamada, Ryoichi Kato, Reo Hamaguchi, Taichiro Goto, and Arafumi Maeshima
- Subjects
Male ,Pulmonary and Respiratory Medicine ,medicine.medical_specialty ,medicine.drug_class ,Biopsy ,Antibiotics ,Mycobacterium Infections, Nontuberculous ,Mycobacterium chelonae ,Lesion ,Bronchoscopy ,medicine ,Humans ,Medical history ,Pneumonectomy ,Respiratory Tract Infections ,Lung ,biology ,medicine.diagnostic_test ,business.industry ,Sputum ,Gastroenterology ,Drug Resistance, Microbial ,Histology ,General Medicine ,Middle Aged ,respiratory system ,biology.organism_classification ,Anti-Bacterial Agents ,respiratory tract diseases ,Surgery ,Treatment Outcome ,medicine.anatomical_structure ,medicine.symptom ,Tomography, X-Ray Computed ,Cardiology and Cardiovascular Medicine ,business - Abstract
Mycobacterium chelonae lung infection is rare and has long been recognized as an enigmatic infection resistant to medical therapy. Recently, we encountered a patient who underwent pulmonary resection for Mycobacterium chelonae infection. A 46-year-old man with no medical history was found to have an abnormal shadow in the left upper lung field on chest X-ray. Computed tomography showed a nodular shadow in the left upper lobe and disseminated shadows around it. Mycobacterium chelonae was detected from cultures of the sputum, bronchial washings, bronchoscopic biopsy specimens, and gastric fluid, and pulmonary infection with Mycobacterium chelonae was diagnosed. The shadow did not decrease in size despite antibiotic treatment. Since the lesion was confined to the left upper segment, we judged that a complete resection was possible, and performed left upper division segmentectomy. After surgery, no new foci of infection were observed in the lung. No effective therapy for Mycobacterium chelonae lung infection has been established to date, and reported cases of pulmonary resection for the treatment of Mycobacterium chelonae infection are extremely rare. However, surgery should be considered in patients in whom complete resection is deemed possible.
- Published
- 2012
42. Microscopic Sclerosing Hemangioma Diagnosed by Histopathological Examination after Lung Cancer Surgery
- Author
-
Taichiro Goto, Ryoichi Kato, and Arafumi Maeshima
- Subjects
Adult ,Pulmonary and Respiratory Medicine ,medicine.medical_specialty ,Pathology ,Lung Neoplasms ,medicine.medical_treatment ,Hemosiderosis ,Adenocarcinoma ,Hemangioma ,Pneumonectomy ,Pulmonary Sclerosing Hemangioma ,Predictive Value of Tests ,Biopsy ,medicine ,Humans ,Lung cancer ,Lung cancer surgery ,Lung ,medicine.diagnostic_test ,business.industry ,Biopsy, Needle ,Gastroenterology ,General Medicine ,medicine.disease ,medicine.anatomical_structure ,Female ,Surgery ,Radiology ,Tomography, X-Ray Computed ,Cardiology and Cardiovascular Medicine ,business ,Calcification - Abstract
A 44-year-old woman underwent surgery for lung cancer. Although preoperative computed tomography did not reveal a tiny nodule, pathological examination of the background lung showed that type II pneumocyte-like tumor cells grew papillary in an area of approximately 2.3 × 1.2 mm. This lesion exhibited hemorrhage, hemosiderosis, calcification, and varying degrees of fibrosis, leading to the diagnosis of sclerosing hemangioma. This is the first reported case of microscopic sclerosing hemangioma undetectable by chest computed tomography.
- Published
- 2011
43. Multi-detector Row CT and Gallbladder Wall Blood Flow by Color Doppler US as a Useful Tool for Pre-operative Diagnosis in 3 Cases of Xanthogranulomatous Cholecystitis
- Author
-
Masahiro Ito, Akihiko Horiguchi, Shuichi Miyakawa, Toru Nishikawa, Toshiyuki Yamamoto, Yukio Asano, Kouichi Furusawa, Ryoichi Kato, Ryota Hanaoka, and Shin Ishihara
- Subjects
medicine.medical_specialty ,business.industry ,Gastroenterology ,medicine ,Surgery ,Radiology ,Color doppler ,Blood flow ,Gallbladder wall ,business ,Multi detector ,Xanthogranulomatous Cholecystitis ,Pre operative - Abstract
黄色肉芽腫性胆嚢炎(Xanthogranulomatous cholecystitis;以下,XGCと略記)は,進行胆嚢癌との鑑別が困難で胆嚢癌と診断された場合,過大手術を施行されることが多く正確な術前診断が重要である.我々の施設では,XGCと進行胆嚢癌の術前鑑別診断に一般的な画像検査に加え,多列検出器CTとカラードプラ断層法による胆嚢壁血流測定を用いている.多列検出器CTでは,XGCの特徴的な所見である胆嚢粘膜の連続性の保持や胆嚢壁内の微細なLow density spotの描出が認められ,これらの所見は進行胆嚢癌には認められないことから鑑別に有用であった.またカラードプラ断層法による胆嚢壁血流測定では,いずれのXGC症例においても胆嚢壁血流の最高流速は進行胆嚢癌と同等の高値を示した.胆嚢壁血管抵抗はXGCでは正常胆嚢と同等の低値であったのに対し,胆嚢癌症例では有意に高値で鑑別診断に有用であった.
- Published
- 2011
44. Solitary Pulmonary Metastasis from Carcinoma of the Papilla of Vater
- Author
-
Kumi Akanabe, Arafumi Maeshima, Ryoichi Kato, Hidejiro Urakami, and Taichiro Goto
- Subjects
Male ,Pulmonary and Respiratory Medicine ,Ampulla of Vater ,Pathology ,medicine.medical_specialty ,Lung Neoplasms ,Biopsy ,medicine.medical_treatment ,Common Bile Duct Neoplasms ,Adenocarcinoma ,digestive system ,Pancreaticoduodenectomy ,Pneumonectomy ,Carcinoma ,Humans ,Medicine ,Pathological ,Lung ,medicine.diagnostic_test ,business.industry ,Gastroenterology ,Solitary Pulmonary Nodule ,General Medicine ,Middle Aged ,medicine.disease ,Immunohistochemistry ,digestive system diseases ,Major duodenal papilla ,Radiation therapy ,Treatment Outcome ,medicine.anatomical_structure ,Lymph Node Excision ,Surgery ,Tomography, X-Ray Computed ,Cardiology and Cardiovascular Medicine ,business - Abstract
Pulmonary metastasis from carcinoma of the papilla of Vater is considered to be a late event, and patients can be treated with radiotherapy, chemotherapy, or palliative surgery. However, surgical treatment of an isolated lung metastasis has not been reported. We present a surgical case of solitary pulmonary metastasis from carcinoma of the papilla of Vater. A 51-year-old man underwent pylorus-preserving pancreaticoduodenectomy for Vater carcinoma. During follow-up, chest computed tomography revealed a nodular shadow in the right lung. The pathological examination demonstrated the appearance of the pulmonary tumor resembled that of the previously resected Vater carcinoma, and both tumors showed similar immunostaining properties, leading to the pathological diagnosis of pulmonary metastasis from carcinoma of the papilla of Vater. Isolated pulmonary metastasis from carcinoma of the papilla of Vater is extremely rare, but surgery could be the treatment of choice.
- Published
- 2011
45. Cavitary Lung Cancer Lined with Normal Bronchial Epithelium and Cancer Cells
- Author
-
Ryoichi Kato, Arafumi Maeshima, Yoshitaka Oyamada, and Taichiro Goto
- Subjects
bronchial epithelium ,Pathology ,medicine.medical_specialty ,business.industry ,Case Report ,Histology ,respiratory system ,medicine.disease ,respiratory tract diseases ,cavitary lung cancer ,surgery ,histology ,Oncology ,Cancer cell ,Medicine ,Adenocarcinoma ,business ,Traction bronchiectasis ,Lung cancer ,Bronchial epithelium ,traction bronchiectasis - Abstract
Reports of cavitary lung cancer are not uncommon, and the cavity generally contains either dilated bronchi or cancer cells. Recently, we encountered a surgical case of cavitary lung cancer whose cavity tended to enlarge during long-term follow-up, and was found to be lined with normal bronchial epithelium and adenocarcinoma cells.
- Published
- 2011
46. Treatment of a patient with triple synchronous primary lung carcinomas
- Author
-
Ken Takeuchi, Ryoichi Kato, and Arafumi Maeshima
- Subjects
medicine.medical_specialty ,Lung ,medicine.anatomical_structure ,business.industry ,medicine ,Radiology ,business - Abstract
症例は88歳男性.2006年健診で異常陰影を認め精査目的に当科を受診した.胸部CTで右上葉末梢,右肺門部と左上葉に結節影を認めた.気管支鏡で,右上葉末梢病変は非小細胞癌と診断した.FDG-PET検査で各結節影に一致して集積を認めた.右肺癌cT1bN1M0および左肺癌cT1bN0M0の重複癌と診断し,まず右上葉切除+リンパ節郭清を,3週後に胸腔鏡下左肺部分切除を施行した.リンパ節転移と考えていた右肺門部の結節は,原発性肺癌であり,3病変はすべて異なる組織型で,それぞれp-I A期であった.術後3年7ヵ月経過した現在再発を認めていない.同時性肺三重癌で組織型がすべて異なる症例は稀である.また高齢者三重癌に対して手術を2期的に施行し,良好な結果が得られた症例は今までに報告されていない.今回われわれは,同時性肺三重癌の一切除例を経験したので文献的考察を加え報告する.
- Published
- 2010
47. Multislice CT study of pancreatic head arterial dominance
- Author
-
Hideo Nagata, Shuichi Miyakawa, Kazuhiro Katada, Akihiko Horiguchi, Masahiro Ito, Yukio Asano, Ryoichi Kato, Shin Ishihara, and Toshiyuki Yamamoto
- Subjects
medicine.medical_specialty ,Dorsal pancreatic artery ,medicine.artery ,Internal medicine ,medicine ,Carcinoma ,Humans ,Pancreas ,Dominance (genetics) ,Hepatology ,business.industry ,Inferior pancreaticoduodenal artery ,medicine.disease ,Carcinoma, Papillary ,Carcinoma, Ductal ,Pancreatic Neoplasms ,medicine.anatomical_structure ,Bile Duct Neoplasms ,Surgery ,Tomography ,Radiology ,Tomography, X-Ray Computed ,business ,Abdominal surgery - Abstract
When a pancreatoduodenectomy is to be conducted, preoperative understanding of the vascular anatomy of the pancreatic head is important in order to reduce intraoperative bleeding. Using multislice computed tomography (MS-CT), we investigated the depiction rate and branching of the inferior pancreaticoduodenal artery (IPDA) and dorsal pancreatic artery (DPA), afferent arteries to the pancreatic head.In 109 patients (68 with pancreatic cancer, 21 with biliary tract cancer, 15 with intraductal papillary mucinous tumor of the pancreas, and 5 others), images were taken, using 64-row MS-CT, in the early and late arterial phases.The depiction rates were 98.2% for the IPDA and 96.3% for the DPA. Branching of the IPDA was categorized into three types: a type in which the IPDA formed a common vessel with the first jejunal branch (72.0%), a type in which the IPDA branched directly from the superior mesenteric artery (18.7%), and a type in which the anterior inferior pancreaticoduodenal artery (AIPDA) and posterior inferior pancreaticoduodenal artery (PIPDA) branched separately (9.3%). DPA branching was categorized into five types, in which the DPA branched from the splenic artery (40.0%), from the common hepatic artery (25.7%), from the superior mesenteric artery (20.0%), and from the celiac artery (8.6%), and a type in which the DPA branching did not follow any of the above patterns (5.7%).MS-CT images of vascular architecture enable evaluation from any angle, which is not possible with conventional angiography, making MS-CT a useful diagnostic imaging technique for understanding the vascular anatomy of the pancreatic head prior to conducting pancreatoduodenectomy for diseases of the pancreatic head region.
- Published
- 2008
48. Pancreatoduodenectomy in which dissection of the efferent arteries of the head of the pancreas is performed first
- Author
-
Hideo Nagata, Tomohiro Shimizu, Akihiko Horiguchi, Shuichi Miyakawa, Kazuhiro Katada, Ryoichi Kato, Shin Ishihara, Koichi Furusawa, and Masahiro Ito
- Subjects
Male ,medicine.medical_specialty ,Efferent ,Dorsal pancreatic artery ,Dissection (medical) ,Pancreaticoduodenectomy ,Gastroduodenal artery ,medicine.artery ,medicine ,Humans ,Superior mesenteric vein ,Ligation ,Pancreas ,Aged ,Retrospective Studies ,Hepatology ,business.industry ,Arteries ,medicine.disease ,Surgery ,Pancreatic Neoplasms ,Treatment Outcome ,medicine.anatomical_structure ,Bile Duct Neoplasms ,Female ,business ,Abdominal surgery ,Artery - Abstract
Pancreatoduodenectomy (PD) is one of the most difficult operations in gastrointestinal surgery. Standard PD ligates and cuts superior mesenteric vein (SMV) branches after the removal of the pancreas head, which leads to congestion and bleeding of these veins. In this study, we modified the standard PD and first ligated the efferent vessels (arteries); namely, the gastroduodenal artery and inferior pancreatoduodenal artery (IPDA), before ligating and cutting the corresponding afferent vessels (veins) of the pancreas head. By doing this, congestion of these veins was relieved and bleeding from the resected surface was substantially prevented. Thirty-six patients (18 underwent standard PD and 18 had modified PD) formed the study population. The amount of bleeding in the modified PD group was significantly lower than that in the standard PD group. (678 ± 329 g vs 1225 ± 375 g, respectively; P < 0.05) However, no difference in operation time was found between the two groups. We believe this modified PD procedure is valuable to enable the safe performance of PD.
- Published
- 2007
49. Hemorrhagic radiation gastritis after chemoradiation therapy for peritoneal lymph node metastasis of esophageal carcinoma successfully treated with repeated intraarterial steroid infusions
- Author
-
Risaburo Sunagawa, Yoshiyuki Komori, Yoichi Sakurai, Ryoichi Kato, Tatsuo Banno, Jun Isogaki, Shuhei Tonomura, Shinpei Furuta, Yasuko Nakamura, Kazuki Inaba, and Ichiro Uyama
- Subjects
medicine.medical_specialty ,Peritoneal Lymph Node ,business.industry ,medicine.medical_treatment ,Gastroenterology ,medicine.disease ,Right gastroepiploic artery ,Surgery ,Metastasis ,medicine.anatomical_structure ,Infusion therapy ,Esophagectomy ,medicine.artery ,medicine ,Carcinoma ,Gastric mucosa ,Lymph ,business - Abstract
Although intraarterial steroid infusion therapy has previously been shown to be effective for inflammatory bowel disease, it has not yet been applied for the treatment of hemorrhagic radiation gastritis. We report herein a case of hemorrhagic radiation gastritis of gastric tube that occurred after chemoradiation therapy for postoperative peritoneal lymph node metastasis in a patient with esophageal carcinoma who had a history of esophagectomy reconstructed with a gastric tube. The hemorrhagic gastritis that occurred in the gastric tube was successfully treated with repeated intraarterial steroid infusions through the regional vessels to the reconstructed gastric tube. A 70-year-old Japanese woman received chemoradiation therapy for metastatic lymph nodes of the celiac axis. Four weeks after completion of chemoradiation therapy, acute persistent bleeding occurred in the gastric mucosa of the reconstructed gastric tube in the irradiated area. Despite application of available therapeutic modalities, her persistent bleeding was intractable, and a total of 50 units of blood transfusion was required to improve progressive anemia. Finally, intraarterial steroid infusion therapy was applied through the right gastroepiploic artery supplying the main blood flow to the gastric tube. Three repeated intraarterial steroid infusions through the right gastroepiploic artery were effective, and hemostasis was finally completed soon after the last dose of intraarterial steroid was given. This case highlights the clinical importance and significance of hemorrhagic radiation gastritis of the reconstructed gastric tube with posterior mediastinal route occurring after chemoradiation therapy. Repeated intraarterial steroid infusion could be one option that appears clinically useful to treat intractable bleeding from radiation gastritis.
- Published
- 2007
50. Calcium-dependent protein phosphorylation in hairy roots of Daucus carota
- Author
-
Ryoichi Kato, Kaori Okuyama, Shoko Sato, Hiroshi Kamada, Masahiro Kodama, and Takashi Suzuki
- Subjects
inorganic chemicals ,biology ,Calmodulin ,Inoculation ,Agrobacterium ,Plant Science ,biology.organism_classification ,environment and public health ,Molecular biology ,In vitro ,enzymes and coenzymes (carbohydrates) ,Plasmid ,Biochemistry ,biology.protein ,bacteria ,Phosphorylation ,Protein phosphorylation ,Agronomy and Crop Science ,Biotechnology ,Daucus carota - Abstract
In vitro protein phosphorylation in soluble fractions (85,000×g supernatant) prepared from carrot hairy roots, which were induced by inoculation with Agrobacterium rhizogenes harboring the Ri plasmid, was analyzed by SDS-PAGE and autoradiography. The autoradiograms indicated that at least four proteins, with molecular masses of 65, 57.5, 52, and 38 kDa, were phosphorylated. The presence of Ca2+ enhanced the phosphorylation of the 65, 57.5, and 52 kDa proteins, but the presence of both Ca2+ and calmodulin did not enhance phosphorylation as much as Ca2+ alone. W-7 strongly inhibited the phosphorylation of the 65, 57.5, and 52 kDa proteins while W-5 mildly inhibited the phosphorylation of these proteins. The extent of phosphorylation of these proteins and the growth rate of the hairy roots became higher with increasing incubation temperature. W-7 had a considerable inhibitory effect on the growth of hairy roots, W-5 had a weak inhibitory effect on the growth of the roots, and a high concentration of TMB-8 inhibited growth. These results suggest that the 65, 57.5, and 52 kDa proteins are phosphorylated by CDPK and that the phosphorylation is connected with the increase in growth of carrot hairy roots.
- Published
- 2007
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.