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71.
The aim of the present study was to analyze the clinical and radiographic outcomes and Kaplan–Meier survivorship of patients who underwent revision surgeries of the acetabular cup that had sustained aseptic loosening. We reviewed 101 consecutive patients (120 hips; 10 men 11 hips; 91 women 109 hips; age at surgery 66 years; range 45–85) who underwent acetabular component revision surgery, at a follow-up period of 15.6 years (range 10–32). To evaluate the state of the acetabulum, acetabular bony defects were classified according to the AAOS classification based on intraoperative findings: type I (segmental deficiencies n = 24 hips), type II (cavity deficiency n = 48), type III (combined deficiency n = 46), and type IV (pelvic discontinuity n = 2). The Harris hip score improved from 42.5 ± 10.8 (mean ± SD) before surgery to 74.9 ± 14.6 points at follow-up. The survival rates of the acetabular revision surgery with cemented, cementless, and cemented cups plus reinforcement devices were 74, 66, and 82 %, respectively. The difference in the survival rate between the cemented and cementless group was marginal (p = 0.048 Gehan–Breslow–Wilcoxon, p = 0.061 log-rank), probably due to the early-stage failure cases in the cementless group. The cementless and reinforcement groups included nine early-stage failure cases. To prevent early-stage failure, we recommend the cementless cups for types I and II acetabular bone defects with adequate contact between host bone and acetabular component, and the cemented cup with or without reinforcement devices, together with restoration of bone stock by impaction or structured bone grafting, for cases lacking such contact.  相似文献   
72.
Objectives:   To evaluate a clinical pathway of discharge on postoperative day 3 for the tension-free vaginal mesh (TVM) procedure in patients with pelvic organ prolapse (POP).
Methods:   Between May 2006 and December 2007, 305 consecutive women with POP quantification stage 3 or 4 were planned to undergo the TVM procedure in a single general hospital. Excluding five patients with concomitant hysterectomy, a pathway (removal of the indwelling urethral catheter on the next morning, discharge on postoperative day 3) was applied to the remaining 300 patients. The perioperative complications and postoperative hospitalization were prospectively evaluated in this case series.
Results:   Perioperative complications were: bladder injury (11 cases, 3.7%), vaginal wall hematoma (two cases, 0.7%), rectal injury (one case, 0.3%) and temporary hydronephrosis (one case, 0.3%). None needed blood transfusion. The indwelling urethral catheters were removed on the next morning as in the pathway in 287 cases (95.6%), and none required clean intermittent catheterization at home. Postoperative hospitalization was within 3 days in 280 cases (93.3%). The six cases (2.0%) with longer hospitalization were due to complications (two cases of bladder injury, one of rectal injury, one of blood loss over 200 mL, one of temporary urinary retention, and one of hydronephrosis). Two patients were re-hospitalized within one month due to vaginal bleeding or gluteal pain.
Conclusions:   Patients generally accepted the pathway of discharge on postoperative day 3 in spite of the Japanese culture preferring a longer hospital stay.  相似文献   
73.
AIM: Although thallium-201 (201Tl) has been used for the diagnosis of lung cancer, its detectability of small pulmonary nodules is not known. The aim of this study was to evaluate the ability of 201Tl SPECT for the differential diagnosis for the pulmonary nodules 20 mm in diameter or smaller. METHODS: 201Tl SPECT was performed in 31 patients suspected of having primary lung cancer. The final diagnosis was established by histology, and tumor size was 10 to 20 mm in diameter. Twenty of 31 patients had malignant tumors, including squamous cell lung cancer (n = 5), adenocarcinoma (n = 14) and small cell lung cancer (n = 1), but in none of them was there mediastinal lymphnode involvement. RESULTS: Ten of 20 malignant tumors and 1 of 11 benign lesions demonstrated significant 201Tl uptake, so that the positive predictive value, negative predictive value, sensitivity and specificity for the diagnosis of lung cancer were 90.9% (10/11), 50.0% (10/20), 50.0% (10/20) and 90.9% (10/11), respectively. CONCLUSION: These data suggest that sensitivity for detecting lung cancer 20 mm or less in diameter may be insufficient, but even in patients with small pulmonary nodules, a positive 201Tl result is highly predictive of lung cancer.  相似文献   
74.
Late recurrence of stage I testicular seminoma is rare. We herein report a case of retroperitoneal lymph node recurrence of testicular seminoma 6 years after high orchiectomy. A 39-year-old man had a left high orchiectomy for stage I testicular tumor in November 1997. Histopathological findings revealed seminoma (pT3). In 2003, follow up computed tomography showed retroperitoneal lymph nodes swelling. Serum tumor markers had been normal since 1997. Retroperitoneal lymph nodes were dissected in April 2004. Histopathological findings were recurrence of seminoma.  相似文献   
75.
Background: This study evaluated the efficacy of repeat hepatic resection for recurrent hepatocellular carcinoma (HCC) and the clinicopathological factors influencing overall survival after resection. Methods: From 1992 to 2005, 231 patients underwent curative hepatic resection for HCC at Yokohama City University, Japan. Of these, 105 patients developed intrahepatic recurrence, and 24 repeat hepatectomies were performed for recurrent HCC. Survival data were analysed, and prognostic factors for repeat hepatic resection were determined. Results: The overall cumulative 1‐, 3‐ and 5‐year survival rates and the median survival time of the patients after initial hepatic resection (n= 231) did not differ from those of the patients after repeat hepatic resection (n= 24), with values of 91.3, 70.2 and 49.1%, and 57 months, versus 91.7, 73.1 and 50.9%, and 61.5 months, respectively (P= 0.875). The operative time and blood loss in patients who underwent repeat hepatic resection did not differ from those who underwent primary resection. Multivariate analysis identified portal invasion at the first hepatic resection and a disease‐free interval of ≤1.5 years after primary hepatic resection as independent risk factors for survival after repeat hepatic resection. The 12 patients who did not show either of the two prognostic factors had 3‐ and 5‐year survival rates of 91.7 and 68.8%, respectively, after repeat hepatic resection. Conclusions: Our findings suggest repeat hepatic resection as the treatment of choice for recurrent HCC patients without portal invasion at the first resection whose recurrence develops after a disease‐free interval of >1.5 years since the previous surgery.  相似文献   
76.
Benign schwannoma of the pancreas   总被引:2,自引:0,他引:2  
Reported cases of intrapancreatic schwannomas have recently increased in the literature. However, none of these cases were diagnosed clearly as schwannoma preoperatively. We herein describe the clinicopathologic findings of a solitary benign schwannoma occurring in the head of the pancreas. Additionally, the differential diagnosis versus other cystic- and solid-appearing pancreatic masses is briefly discussed.  相似文献   
77.
BACKGROUND: The aim of this study was to evaluate the impact of patient age on surgical therapy for colorectal liver metastases. STUDY DESIGN: Between 1992 and 2004, 212 consecutive patients underwent potentially curative hepatic resection. Sixty-two patients were 70 years or older at the time of resection (older group) and 150 patients were less than 70 years at the time of resection (younger group). RESULTS: A proportion of older patients had a history of severe cardiopulmonary disease (32.3%) and respiratory insufficiency (6.5%). Intraoperative variables, such as resected liver volume, operation time, estimated blood loss, and blood transfusion, were not notably different between older and younger patients. Postoperative complications after resection occurred in 19.7% of older patients and at a similar rate (23.3%) in the younger group. Resection mortality was 0% in older patients and 0.49% in younger patients. The 5-year survival rates of older and younger patients were 34.1% and 53.1%, respectively. Compared with younger patients, the overall survival rate of older patients was markedly lower (p<0.01). CONCLUSIONS: Advanced chronologic age cannot be regarded as a medical contraindication for hepatic resection of colorectal liver metastases in patients who are more than 70 years of age.  相似文献   
78.
Aim:  This study aims to establish a pressure ulcers model that visualizes the microcirculation, and to examine the participation of ischemia‐reperfusion injury in the pathophysiology of pressure ulcers.
Methods:  An original system composed of a new skinfold chamber and compression device allowed loading quantitative vertical stress to the skin. An intravital microscopic technique enabled direct visualization of the microcirculation in the physiological condition and in response to pressure application. To estimate the effect of ischemia‐reperfusion injury, animals were divided into two groups: the compression‐release group in which the animals received four cycles of compression‐release which consisted of 2 hours of compression followed by 1 hour of pressure release; and the compression alone group in which the animals underwent continuous compression for 8 hours. Functional capillary density was quantified before the compression procedure and on day1 (35 hours) after the first evaluation.
Results and Conclusions:  The cyclic compression‐release procedure significantly decreased functional capillary density as compared to continuous compression, indicating that in our experimental setting repetition of ischemia‐reperfusion cycle more severely damaged the microcirculation than single prolonged ischemic insult. The finding supports the significant contribution of ischemia‐reperfusion injury to the pathophysiology of pressure ulcers at the level of dynamic in vivo microcirculation.  相似文献   
79.
Background  Simultaneous bilateral total hip arthroplasty (THA) can offer a potential benefit of greater postoperative hip motion without the negative influence of contralateral hip disabilities, compared to two-stage THA. However, postoperative changes in hip motion after simultaneous bilateral THA have rarely been reported. The purpose of this study was to clarify the efficacy of simultaneous procedures on postoperative hip motion and functional recovery. Methods  We retrospectively compared hip motion in 27 patients treated with simultaneous bilateral THA to those in 11 patients with two-stage bilateral THA, 35 patients with unilateral THA for unilateral disease, and 15 patients with unilateral THA for bilateral disease. We also evaluated the clinical manifestations according to the Japanese Orthopaedic Association (JOA) hip scores and compared the outcomes among the groups. All of the THA surgeries were primarily performed through a posterolateral approach using cement-less prostheses. The diagnosis at surgery was dysplastic osteoarthritis in all patients, and the patients were followed up for at least 4 years. Results  The postoperative improvement of motion in hip flexion was significantly greater in patients treated with simultaneous procedures compared to patients with two-stage THA and unilateral THA for bilateral disease. The differences in improvement of motion in hip abduction were less marked than the improvement in hip flexion among the groups. Although there were no significant differences in pain scores among the groups, the values for activity of daily living were significantly greater in patients treated with simultaneous bilateral THA and patients with unilateral THA for unilateral disease than in patients with unilateral and two-stage bilateral THA for bilateral disease. Conclusions  The simultaneous procedure was considered to be more effective in patients with bilateral hip osteoarthritis and demonstrated a substantial improvement in hip motion and functional recovery after THA.  相似文献   
80.

Background

To date, several training and evaluation systems for endoscopic surgery have been developed, such as virtual-reality simulators and box trainers. However, despite current advances in these objective assessments, no functional brain studies during learning of endoscopic surgical skills have been carried out. In the present study, we investigated cortical activation using near-infrared spectroscopy (NIRS) during endoscopic surgical tasks.

Study design

A total of 21 right-handed subjects, comprising 4 surgical experts, 4 trainees, and 13 novices, participated in the study. Suturing and knot-tying tasks were performed in a box trainer. Cortical activation was assessed in all subjects by task-related changes in hemoglobin (Hb) oxygenation using NIRS.

Results

In surgical experts and novices with no experience of endoscopic surgical training, we found no changes in oxy-Hb, deoxy-Hb or total-Hb levels in any of the frontal channels. In surgical trainees and one novice with experience of endoscopic surgical training, we found significant increases in oxy-Hb and total-Hb levels in most of the frontal channels. There were significant differences in oxy-Hb and total-Hb levels in CH-19 between surgical experts and trainees (p = 0.02 for both), and between surgical trainees and novices with no experience of endoscopic surgical training (p = 0.008 for both). Furthermore, additional training increased oxy-Hb levels in the frontal cortex of novices with no experience of endoscopic surgical training but had no such effect on surgical experts.

Conclusions

The present data suggest that NIRS is a feasible tool for assessing brain activation during endoscopic surgical tasks, and may have a large impact on the future development of teaching, training, and assessment methods for endoscopic surgical skills.  相似文献   
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