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排序方式: 共有8342条查询结果,搜索用时 15 毫秒
91.
Susumu Moriya Yukio Miki Tamotsu Kamishima Tosiaki Miyati Mitsunori Kanagaki Yukako Matsuno Tsuneo Yokobayashi 《European journal of radiology》2013
Objectives
To investigate whether rice pads can eliminate lingering fat signals of the complex surface shape of both hands that occur with chemical shift selective (CHESS) at 1.5 T and 3.0 T.Materials and methods
T1-weighted images were obtained with CHESS using 1.5 T and 3.0 T systems. The same imaging parameters were used with and without rice pads on the coronal plane of both hands in 10 healthy volunteers. The fat-suppression effects were classified into four categories and scored for images, and visual evaluations were performed by one radiologist and one radiologic technologist.Results
At 1.5 T, the mean evaluation score was 1.55 for images obtained without rice pads and 3.50 for images obtained with rice pads. At 3.0 T, the mean evaluation score was 1.10 for images obtained without rice pads and 3.20 for images obtained with rice pads. With both systems, images obtained with the rice pads showed significantly better fat suppression effects than images obtained without rice pads (P < 0.0001, P < 0.0001).Conclusions
It was confirmed that lingering fat signals are eliminated and good fat-suppressed images are obtained with the use of rice pads at 1.5 T and 3.0 T. Rice pads are therefore useful with at 1.5 T and 3.0 T, which are currently becoming more widely used. 相似文献92.
Gou Ogasawara Yusuke Inoue Yoshihiro Itoh Satomi Tagami Keiji Matsunaga Kenji Miki 《Annals of nuclear medicine》2013,27(5):487-491
Objective
We evaluated intra- and interoperator reproducibilities in calculating the conventional indices HH15 and LHL15 from 99mTc-diethylenetriamine pentaacetic acid galactosyl human serum albumin (99mTc-GSA) scintigraphy, and proposed new, simple methods for the calculation of quantitative indices.Methods
The results of 99mTc-GSA scintigraphy in 33 patients were retrospectively analyzed. Heart and liver ROIs were drawn manually to cover cardiac blood pool and entire liver, respectively, and HH15 and LHL15 were calculated. In addition, square regions of interest (ROIs) of fixed sizes were placed at the highest activity in blood pool and the liver. Using the square heart ROI, sHH15, an equivalent of HH15, was computed. Fractional liver uptake at 15 min (FLU15) was calculated using the square heart and liver ROIs. Intra- and interoperator reproducibilities, as well as correlation with Indocyanine green retention rate at 15 min (ICG R15), were assessed for these four indices by linear regression analysis.Results
Substantial intra- and interoperator variabilities were found for HH15 and LHL15. The correlation coefficients for intra- and interoperator comparisons were 0.884 and 0.869 for HH15, respectively, and 0.919 and 0.917 for LHL15, respectively. The use of square ROIs instead of hand-drawn ROIs improved reproducibility. The correlation coefficients for intra- and interoperator comparisons were 0.988 and 0.973 for sHH15, respectively, and 0.989 and 0.975 for FLU15, respectively. Correlation with ICG R15 was better for sHH15 (r = 0.619) and FLU15 (r = ?0.656) than for HH15 (r = 0.439) and LHL15 (r = ?0.490).Conclusions
HH15 and LHL15 showed substantial intra- and interoperator variabilities, and the use of square ROIs are indicated to provide better reproducibility. 相似文献93.
Hand assisted retroperitoneoscopic nephroureterectomy: comparison with the open procedure 总被引:11,自引:0,他引:11
Kawauchi A Fujito A Ukimura O Yoneda K Mizutani Y Miki T 《The Journal of urology》2003,169(3):890-894
PURPOSE: We report our initial experience with hand assisted retroperitoneoscopic nephroureterectomy for upper urinary tract transitional cell carcinoma and compared our results to those of a contemporary series of open nephroureterectomy. MATERIALS AND METHODS: Clinical data on 34 consecutive patients who underwent hand assisted retroperitoneoscopic nephroureterectomy were reviewed and compared with those on 34 who underwent open nephroureterectomy. All specimens were extracted intact. RESULTS: Total operative time was similar in the 2 groups (233 versus 236 minutes). Estimated blood loss was significantly less in the hand assisted laparoscopy group (236 versus 427 ml.). During convalescence the frequency of parenteral analgesia postoperatively was significantly lower in the laparoscopy group than in the open surgery group. The former patients had a significantly shorter interval to oral intake and ambulation as well as a shorter hospital stay and convalescence compared with those who underwent open surgery. In each group the complication rate was 12% (4 of 34 cases). In the hand assisted laparoscopy group 1 conversion to an open procedure was due to bleeding. There was recurrence in 4 of the 34 patients (12%) in the laparoscopy group, including 2 with bladder recurrence and 2 with metastases, at an average followup of 13.1 months. CONCLUSIONS: Hand assisted retroperitoneoscopic nephroureterectomy is an effective and safe alternative to open nephroureterectomy for upper urinary tract transitional cell carcinoma. 相似文献
94.
95.
Surgery for pulmonary metastases from colorectal cancer 总被引:2,自引:0,他引:2
Masahiko Higashiyama Ken Kodama Naozumi Higaki Koji Takami Kohei Murata Masao Kameyama Hideoki Yokouchi 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2003,51(7):289-296
OBJECTIVE: Several investigators have analyzed prognostic factors of surgical treatment for pulmonary metastases from colorectal cancer, but the results remain inconclusive. This study was performed to determine the prognostic implications of the prethoracotomy serum level of carcinoembryonic antigen (CEA) in relation to the postthoracotomy recurrent pattern among patients with this disease. METHODS: A retrospective analysis of prognostic factors was undertaken in 100 patients who had consecutively undergone initial surgical resection for pulmonary metastases of colorectal origin. RESULTS: The overall 3- and 5-year survival rates were 62.2% and 49.4%, respectively. Univariate analysis revealed that the prethoracotomy serum CEA level and operative curability were strongly associated with prognosis, while in multivariate analysis, only the prethoracotomy serum CEA level was a significant prognostic indicator. Patients with a high level of prethoracotomy serum CEA more frequently exhibited recurrence in extrathoracic sites, especially in the brain. CONCLUSION: Before thoracotomy for pulmonary metastases from colorectal cancer, the serum CEA level was the most useful prognostic factor. Patients with elevated serum CEA level should undergo a careful prethoracotomy systemic survey and postthoracotomy follow-up for extrathoracic metastases, in particular brain metastases, and an appropriate combined therapeutic modality should be considered. 相似文献
96.
OBJECTIVE: The conclusions remain controversial about whether the sternal blood flow is preserved or diminished after internal thoracic artery (ITA) harvesting for coronary artery bypass grafting (CABG), especially in diabetic patients. We investigated the blood supply of the chest wall noninvasively using near-infrared spectroscopy (NIRS) immediately after CABG. METHODS: The study group comprised 30 patients who underwent CABG using a skeletonized left ITA through median sternotomy. As a control group, three nondiabetic patients undergoing valve surgery through median sternotomy were also included. On arrival of the patient in the intensive care unit immediately after surgery, two reflectance sensors were placed on the bilateral parasternal regions at the fourth intercostal space to record regional oxygen saturation (rSO(2)) and hemoglobin index (HbI) continuously approximately for 17 h. RESULTS: The differences in right and left values (R-L rSO(2) and R-L HbI) were significantly greater in the diabetic patients than in the nondiabetic patients (3.74% +/- 2.47% vs. 1.98% +/- 1.67 %, p = 0.036; and 0.28 +/- 0.19 vs. 0.13 +/- 0.13, p = 0.020). The R-L HbI was significantly greater in the on-pump patients than in the off-pump patients, although there was no significant difference in R-L rSO(2). Both R-L rSO(2) and R-L HbI were similar among the control, nondiabetic, and off-pump patients. CONCLUSION: The technique of NIRS enables noninvasive, continuous monitoring of chest wall perfusion immediately after ITA harvesting. Our study using NIRS showed a decrease in blood flow and oxygen metabolism of the hemisternum after LITA harvest in diabetic CABG patients. 相似文献
97.
Methylprednisolone and interleukin-10 reduce gray matter damage in the contused Fischer rat thoracic spinal cord but do not improve functional outcome 总被引:10,自引:0,他引:10
The effects of two antiinflammatory and neuroprotective agents, methylprednisolone (MP) and interleukin-10 (IL-10), singly and in combination on tissue damage, axonal preservation and functional recovery were studied in the contused adult Fischer rat thoracic spinal cord 12 weeks after injury. MP (30 mg/kg at 5 min, and 2 and 4 h after injury) was administered intravenously and IL-10 (15 or 30 microg/kg at 30 min after injury), intraperitoneally. MP, IL-10, or the combination significantly reduced the volume of damaged tissue (including cavities) compared to control animals. The loss of spinal tissue (cavities) was reduced after treatment with MP alone or combined with IL-10, but not with IL-10 alone. The reduction in tissue damage was confined to spinal gray matter; at the level of the lesion epicenter, the thickness of the lateral white matter columns was similar in all groups. Retrograde tracing using fast blue revealed that the number of spared propriospinal and supraspinal projections was similar in all groups at 12 weeks after the contusion. The open-field BBB-test showed no significant difference in hindlimb locomotion between groups. Our results demonstrate that all tested antiinflammatory treatments significantly increase the volume of spared spinal gray matter 3 months after a moderate contusion of the Fischer rat thoracic spinal cord, but none of the treatments improved axonal preservation or functional recovery. 相似文献
98.
Endoscopic thyroidectomy and parathyroidectomy by the axillary approach 总被引:15,自引:0,他引:15
Background: The use of endoscopic procedures leads to a reduction in the size of the surgical scar, making it more inconspicuous.
In this paper, we evaluated the merits and limits of endoscopic neck surgery. Methods: Between August 1999 and July 2000,
102 patients underwent neck surgery in our department for thyroid or parathyroid disease. Twenty-eight of them were treated
by the axillary. A 12-mm and two 5-mm trocars were inserted through the skin of the axilla. Carbon dioxide was then insufflated
up to 4 mmHg, and the endoscopic surgery was performed. Results: Endoscopic procedures were performed successfully in 26 cases
(19 thyroidectomies and seven parathyroidectomies). There were two conversions to open procedures. The mean operating times
for the thyroidectomies and parathyroidectomies were 212 and 171 min, respectively. No evidence of injury to the recurrent
laryngeal nerve was observed in any of the cases. The postoperative cosmetic status of the patients was excellent. Conclusion:
We believe that endoscopic thyroidectomy and parathyroidectomy by the axillary approach will find a role in the treatment
of endocrine diseases in the neck. 相似文献
99.
Association of cavernous malformation within vestibular schwannoma: immunohistochemical analysis of matrix metalloproteinase-2 and -9 总被引:1,自引:0,他引:1
A 65-year-old man presented with a rare case of cavernous malformation with hemorrhage located within vestibular schwannoma. He had suffered hearing impairment for 20 years, and was admitted to our hospital with vertigo and ataxic gait. Neurological examination revealed hearing loss, facial nerve paresis, and left cerebellar ataxia. Magnetic resonance imaging demonstrated a left vestibular schwannoma 35 mm in diameter, as well as a heterogeneous area associated with hypointense rim within the tumor, indicating intratumoral hemorrhage. Subtotal removal of the tumor together with the fibrously encapsulated hematoma was performed through a left retrosigmoid craniotomy. Histological examination of the surgical specimen revealed cavernous malformation within vestibular schwannoma. Immunohistochemistry for matrix metalloproteinase (MMP)-2 and -9, and tissue inhibitors of metalloproteinase-2 showed strong expression in the endothelial cells of the cavernous malformation, but not in the interstitial structures. His symptoms significantly improved after surgery and he underwent gamma-knife therapy for the residual tumor. Cavernous malformations may show dynamic characteristics such as repeated hemorrhage and de novo formation. MMP-2 and -9, which are implicated in angiogenesis and hemorrhage, may be upregulated in such tumors. 相似文献
100.
BACKGROUND: Surgical revascularization for moyamoya disease prevents cerebral ischemic attacks by improving CBF, but little is known about the change in CBF and its effect on neurologic status during the acute stage after revascularization. METHODS: 123I-IMP-SPECT was performed 1 and 7 days after STA-MCA anastomosis on 34 sides of 27 consecutive patients with adult-onset moyamoya disease (6 men, 21 women; 22-62 years old). The follow-up period ranged from 5 to 28 months (mean, 17.6 months). RESULTS: Thirteen patients (13 sides, 38.2%) suffered temporary neurologic deterioration due to hyperperfusion several days after surgery, which was sustained for several days (7.4 days in average). Postoperative magnetic resonance imaging/angiography showed the STA as a higher intensity signal than the preoperative finding without ischemic changes in all 13 patients. Postoperative SPECT revealed focal intense increase in CBF at the sites of anastomosis in all 13 patients. Eleven patients (32.4%) had transient focal neurologic deficit mimicking ischemic attack. Two patients (5.9%) had cerebral hyperperfusion syndrome associated with subarachnoid hemorrhage extending to the ipsilateral sylvian cistern. Symptoms were relieved by intensive blood pressure control, and no patients had permanent neurologic deficit or delayed neurologic deterioration during the follow-up period. CONCLUSIONS: Surgical revascularization including STA-MCA anastomosis is a safe and effective treatment for moyamoya disease, although temporary neurologic deterioration due to hyperperfusion could occur at a substantial rate. Routine CBF measurement is recommended for accurate diagnosis of postoperative hyperperfusion in moyamoya disease because its treatment is contradictory to that for ischemia. 相似文献