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91.
92.
Vascular flow patterns of hepatic tumors in contrast-enhanced 3-dimensional fusion ultrasonography using plane shift and opacity control modes. 总被引:4,自引:0,他引:4
Masao Ohto Hirotoshi Kato Hirohiko Tsujii Hitoshi Maruyama Shoichi Matsutani Hitoshi Yamagata 《Journal of ultrasound in medicine》2005,24(1):49-57
OBJECTIVE: This study was conducted to determine whether contrast-enhanced 3-dimensional (3D) fusion ultrasonography with combined use of the plane shift and opacity control modes can serve as a useful tool for identifying the vascular characteristics of hepatic tumors in 3D perspective. METHODS: Contrast-enhanced 3D fusion ultrasonography was performed in 31 patients with hepatic tumors after the intravenous injection of contrast media. The shapes, courses, and distributions of tumor vessels, displayed in 3D perspective, were examined to identify the characteristic vascular flow patterns of various tumors. Images before and after contrast media administration were compared for evaluation of the effectiveness of contrast enhancement with regard to tumor diameter for various types of tumors. The images were interpreted in a blinded manner by 3 physicians specializing in abdominal ultrasonography, and vascular flow patterns were determined on the basis of consensus. RESULTS: The characteristic vascular flow patterns observed in hepatocellular carcinomas are reticular flow within the tumor and flow showing a ringlike distribution surrounding the tumor. Metastatic tumors show a vascular flow pattern running between adjacent tumor nodules, and hemangiomas show localized nodular flow at the tumor margins. Contrast enhancement was found to be useful for showing the vascular flow patterns in small hepatocellular carcinomas and hemangiomas. CONCLUSIONS: Contrast-enhanced 3D fusion ultrasonography makes it possible to display images combining the plane shift and opacity control modes to show tumor vessels, including minute vascular flow within hepatic tumors, in 3D perspective and to identify tumor-specific vascular flow patterns. 相似文献
93.
Yukitaka Nimura Takayuki Kitasaka Hirotoshi Honma Hirotsugu Takabatake Masaki Mori Hiroshi Natori Kensaku Mori 《International journal of computer assisted radiology and surgery》2013,8(3):353-363
Purpose Chronic obstructive pulmonary disease (COPD) is characterized by airflow limitations. Physicians frequently assess the stage using pulmonary function tests and chest CT images. This paper describes a novel method to assess COPD severity by combining measurements of pulmonary function tests (PFT) and the results of chest CT image analysis. Methods The proposed method utilizes measurements from PFTs and chest CT scans to assess COPD severity. This method automatically classifies COPD severity into five stages, described in GOLD guidelines, by a multi-class AdaBoost classifier. The classifier utilizes 24 measurements as feature values, which include 18 measurements from PFTs and six measurements based on chest CT image analysis. A total of 3 normal and 46 abnormal (COPD) examinations performed in adults were evaluated using the proposed method to test its diagnostic capability. Results The experimental results revealed that its accuracy rates were 100.0 % (resubstitution scheme) and 53.1 % (leave-one-out scheme). A total of 95.7 % of missed classifications were assigned in the neighboring severities. Conclusions These results demonstrate that the proposed method is a feasible means to assess COPD severity. A much larger sample size will be required to establish the limits of the method and provide clinical validation. 相似文献
94.
Tomoko Kagiya Kazuya Shiogama Ken-Ichi Inada Hirotoshi Utsunomiya Masayuki Kitano 《ACTA HISTOCHEMICA ET CYTOCHEMICA》2022,55(2):67
Nodular lymphoid hyperplasia (NLH) of the human colon has been associated with multiple diseases and symptoms. Causes include food allergies, infections, inflammatory bowel disease, and immunodeficiency, and gastrectomy is not usually considered to be the etiology. Nine rats two weeks after total gastrectomy and 12 control rats were sacrificed and submitted for histological examination. In the gastrectomy group, we found lymphoid hyperplasia throughout the entire colon mucosa. The cross-sectional area of lymphoid follicles was increased to be five-fold larger than that in the rats in the control group (sham surgery). Lymphoid follicles were classified into primary and secondary follicles according to the presence/absence of germinal centers; the gastrectomy group had a significantly larger number of secondary follicles. When T cell and B cell classification of lymphocytes was performed, there was no difference between gastrectomy and control groups at T:B = 40:60. When the lymphoid follicles were classified, the proportion of T lymphocytes increased in the secondary follicle (T:B = 40:60) compared with in the primary follicle (T:B = 20:80). Gastrectomy significantly activated lymphocytic intestinal immunity by altering the intestinal environment, causing colonic NLH. Gastrectomy in rats is a good animal model for the study of NLH in colorectal diseases. 相似文献
95.
AIM: To evaluate the image quality of MR angiography (MRA) with a peripheral vascular coil. MATERIALS AND METHODS: A peripheral vascular coil, a technical coil used in MRA of the pelvis and lower extremities, has 12 individual coil elements arranged in six pairs. We evaluated the performance of a peripheral vascular coil for image quality, signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and visual evaluation by comparing it to a body coil using a phantom. RESULTS: SNR with the peripheral vascular coil was 1.5-2.2 times higher than that with the body coil in vertical distance, and 1.6-1.8 times higher in horizontal distance. CNR with the peripheral vascular coil was 2.1-3.8 times higher than that with the body coil. Visual evaluation with the peripheral vascular coil was 1.1-1.2 times higher than with the body coil in spin echo sequences, and 1.2-1.9 times higher in 3D fast spoiled GRASS (3D-FSPGR) sequences. CONCLUSION: The peripheral vascular coil for peripheral MRA is robust and accurate in evaluating peripheral vascular diseases. 相似文献
96.
Hasegawa H Watanabe M Baba H Nishibori H Kitajima M 《Journal of laparoendoscopic & advanced surgical techniques. Part A》2002,12(6):403-406
BACKGROUND: Significant concern continues about the feasibility of laparoscopic restorative proctocolectomy (RP) with an ileal J pouch anal anastomosis in the surgical treatment of patients with ulcerative colitis (UC). The aim of this study was to clarify the feasibility of laparoscopic RP at a single institution where the surgical routine of laparoscopic colorectal surgery has already been established. PATIENTS AND METHODS: Between July 1994 and December 2001, 18 patients with UC underwent laparoscopic RP. The median age was 30 (range, 18-51) years, and the median follow-up was 20 (range, 5-89) months. Five trocars were placed. After the entire colon and rectum were mobilized and the vessels were divided intracorporeally, the rectum was divided with use of a laparoscopic linear stapler. A pouch anal anastomosis was fashioned with use of a double stapling technique. A diverting loop ileostomy was fashioned. RESULTS: There were no conversions to the open procedure. The median operative time and median blood loss were 360 (range, 290-500) minutes and 105 (range, 10-586) mL, respectively. Six postoperative complications occurred (wound sepsis, 2; bowel obstruction, 1; anastomotic stricture, 2; pouchitis, 1). In one patient, a bowel obstruction developed 3 months after the operation, which was managed conservatively. The median length of the hospital stay was 9 (range, 7-21) days. CONCLUSIONS: The laparoscopic RP is safe and feasible in selected patients with UC. New laparoscopic instrumentation, such as a linear stapler, and a more reliable laparoscopic coagulating and dividing tool should be designed, which would make it possible to perform this procedure more frequently in the surgical treatment of UC. 相似文献
97.
Chikara Kunisaki Hirochika Makino Ryo Takagawa Kei Sato Mayumi Kawamata Amane Kanazawa Naoto Yamamoto Yasuhiko Nagano Shoichi Fujii Hidetaka A. Ono Hirotoshi Akiyama Hiroshi Shimada 《Surgical endoscopy》2009,23(9):2085-2093
Background Some studies have found high incidences of intraoperative and postoperative complications for patients with gastric cancer.
To determine the predictive factors for the surgical complications of laparoscopic gastric surgery, surgical outcomes were
evaluated.
Methods Between April 2002 and December 2007, 152 patients with preoperatively diagnosed early gastric cancer who underwent laparoscopy-assisted
distal gastrectomy (LADG) were enrolled. Visceral (VFA) and subcutaneous fat areas (SFA) were assessed by Fat Scan software.
The predictive factors for surgical complications of LADG were evaluated by univariate and logistic regression analyses.
Results Of 152 patients, conversion to open surgery due to uncontrollable bleeding was observed in nine male patients, and postoperative
complications were detected in seven male and one female patient (four anastomotic leakage, two intraabdominal abscess, one
pancreatic fistula, and one lymphorrhea). High body mass index (BMI) and high VFA independently predicted conversion to open
surgery and postoperative complications. VFA was significantly higher, operation time was longer, blood loss was greater,
and SFA was lower in male than in female patients, whereas no significant difference was observed in BMI between male and
female patients.
Conclusions High BMI and high VFA can predict technical difficulties during laparoscopic gastric surgery and postoperative complications.
Particularly, LADG should be performed cautiously to prevent surgical complications for male patients with high VFA. Predictive
impact of VFA should be further determined in a larger set of patients. 相似文献
98.
Clinicopathological features of gastric carcinoma in younger and middle-aged patients: A comparative study 总被引:2,自引:0,他引:2
Chikara Kunisaki M.D. Ph.D. Hirotoshi Akiyama M.D. Ph.D. Masato Nomura M.D. Goro Matsuda M.D. Yuichi Otsuka M.D. Hidetaka Andrew Ono M.D. Ph.D. Ryo Takagawa M.D. Yutaka Nagahori M.D. Ph.D. Masazumi Takahashi M.D. Ph.D. Fumihiko Kito M.D. Ph.D. Hiroshi Shimada M.D. Ph.D. 《Journal of gastrointestinal surgery》2006,10(7):1023-1032
Gastric carcinoma is relatively rare in patients under the age of 40. This study was undertaken to clarify the clinicopathological
characteristics and surgical outcomes of gastric carcinoma in younger patients compared with those of middle-aged patients.
The surgical results from 131 younger patients (aged ⩽40 years) and 918 middle-aged patients (aged 55–65 years) were compared
retrospectively. Female gender, undifferentiated tumor type and lymphatic invasion were significantly more common in the younger
patients. Survival time did not differ between the two groups. The depth of tumor invasion was the only prognostic factor
in younger patients, whereas macroscopic appearance, tumor diameter, depth of invasion, lymph node metastasis, and venous
invasion were all significant prognostic factors in middle-aged patients. Peritoneal recurrence was significantly more common
in younger patients. A family history of gastric adenocarcinoma was observed in 25.9% of younger patients, but this did not
affect survival outcomes. As depth of invasion affects prognosis independently, and peritoneal metastasis is the predominant
pattern of recurrence, it is essential to establish an optimal prophylactic treatment for peritoneal metastasis to improve
surgical outcomes in younger patients with advanced gastric cancer. 相似文献
99.
Kunisaki C Makino H Kosaka T Oshima T Fujii S Takagawa R Kimura J Ono HA Akiyama H Taguri M Morita S Endo I 《Surgical endoscopy》2012,26(3):804-810
Background
The aim of this study was to clarify the technical feasibility and oncological efficacy of laparoscopy-assisted gastrectomy (LAG) for gastric cancer compared with open gastrectomy (OG).Methods
Between April 2002 and March 2008, a series of 623 patients with gastric cancer underwent R0 gastrectomy (314 LAG patients and 309 OG patients). Age, gender, lymph node dissection, and pathological stage were matched by propensity scoring, and 212 patients (106 LAG and 106 OG) were selected for analysis after the exclusion of 40 patients who had proximal gastrectomy. Intraoperative factors, postoperative morbidity, long-term quality of life (QOL), and survival were evaluated. Moreover, these outcomes were also compared between the laparoscopy-assisted total gastrectomy (LATG) and the open total gastrectomy (OTG).Results
There was no significant difference in preoperative characteristics between the two patient groups. Regarding intraoperative characteristics, blood loss was significantly lower in the LAG group (143?ml) than in the OG group (288?ml), while operation time was significantly longer in the LAG group (273?min) than the OG group (231?min). The degree of lymph node dissection and number of retrieved lymph nodes did not differ between the two groups. There were no significant differences in postoperative courses or overall and disease-specific survival (89.8% vs. 83.6%, P?=?0.0886; 100% vs. 95.2%, P?=?0.1073) except time to first flatus and time to use of nonsteroidal anti-inflammatory derivatives between the two groups. Significantly fewer patients felt wound pain in the LAG group 1?year after surgery. Analyses between the LATG and OTG groups showed similar results.Conclusions
LAG for gastric cancer may be both feasible and safe. However, it will be necessary to conduct a well-designed randomized controlled trial comparing short-term and long-term outcomes between LAG and OG in a larger number of patients. 相似文献100.
Shin-ichiro Ohmura Yoichiro Homma Takayuki Masui Toshiaki Miyamoto 《Internal medicine (Tokyo, Japan)》2022,61(7):997
Objective To investigate the risk factors for the development of Pneumocystis jirovecii pneumonia (PCP) in patients with rheumatoid arthritis (RA) undergoing methotrexate (MTX) therapy. Methods This single-center retrospective cohort study included consecutive patients with RA who received MTX for at least one year. The study population was divided into PCP and non-PCP groups, depending on the development of PCP, and their characteristics were compared. We excluded patients who received biologic disease-modifying anti-rheumatic drugs (DMARDs), Janus kinase inhibitors, and anti-PCP drugs for prophylaxis. Results Thirteen patients developed PCP, and 333 did not develop PCP. At the initiation of MTX therapy, the PCP group had lower serum albumin levels, a higher frequency of pulmonary disease and administration of DMARDs, and received a higher dosage of prednisolone (PSL) than the non-PCP group. A multivariate Cox regression analysis revealed that the concomitant use of PSL [hazard ratio (HR) 5.50, p=0.003], other DMARDs (HR 5.98, p=0.002), and serum albumin <3.5 mg/dL (HR 4.30, p=0.01) were risk factors for the development of PCP during MTX therapy. Patients with these risk factors had a significantly higher cumulative probability of developing PCP than patients who lacked these risk factors. Conclusion Clinicians should pay close attention to patients with RA who possess risk factors for the development of PCP during MTX therapy. 相似文献