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61.
Twenty children are presented after undergoing a distally based superficial sural flap for coverage of defects at the lower leg and foot. The age of the patients was between 1 and 12 years. Fifteen patients had trauma to the lower leg, with eight of them having associated injuries. Three had postburn contracture and two had pressure sore. In 14 cases, the flap was used as a fasciocutaneous flap, whereas in six cases it was used as a fascial flap covered with a skin graft. The flaps were used to cover the defects from the dorsum of the foot distally up to the mid third of tibia proximally. The mean follow-up was for a period of 2 years. Even though free tissue transfer is reliable and safe for the reconstruction of major leg injuries in children, the distally based superficial sural flap has the advantage of being easy to perform, with short operating time, minimal donor side morbidity, and preservation of major arteries of the leg.  相似文献   
62.
Background Despite improving surgical techniques, treatment of heart valve disease in children remains controversial. Somatic growth and adequate anticoagulation are of concern when children undergo valve replacement. We conducted this study to evaluate the performance of valves in this age group. Methods 42 children under the age of 13 years who underwent valve replacement were included in this study. Totally, 50 valves were implanted in 42 patients: 48 were mechanical prostheses, two were bioprosthetic both in pulmonary position. 37 (74%) valves were implanted in mitral position, 10 (20%) in aortic position, 1 (2%) in tricuspid position and 2 (4%) in pulmonary position. Preoperatively, 14 (33,3%) patients were in New York Heart Association (NYHA) class IV, while 27 (64.2%) were in NYHA class III. Results There were 2 (4.7%) hospital deaths and 2 (4.7%) late deaths while 2 (4.7%) patients were lost to follow up. The mean follow up period was 9.4 yrs. 35 (83.3%) patients are in NYHA Class I and free of all medications except warfarin. 3 (7.1%) patients have undergone 5 successful pregnancies. The median INR was 2.23. Major thrombo-embolic episode occurred in 1 (2.3%) patient. Conclusions In view of the problems of sizing, anticoagulation and need for re-operation at an early age, there is a reluctance to replace valves in children. This study shows that despite these problems, valve replacement can be undertaken safely and successfully in children, when repair has failed or not technically feasible.  相似文献   
63.
BACKGROUND: This study sought to characterize the variables that predict postoperative prostate-specific antigen doubling time (PSADT) and biochemical recurrence time (RT) in patients who have failed radical prostatectomy (RP). METHODS: A total of 477 patients underwent RP at our institution for clinically localized prostate cancer. Of these patients, 64 (13.4%) demonstrated evidence of postoperative biochemical failure. PSADT and biochemical RT were calculated for all patients. PSADT and RT were correlated with clinical variables including preoperative PSA level, patient age, race, prostate weight and with pathologic characteristics of the operative specimen using uni- and multivariate analyses. In addition, PSADT and RT were also correlated with each other and with the time to postoperative adjuvant therapy. RESULTS: Median postoperative PSADT for patients who recurred after radical prostatectomy was 9.7 months. Postoperative PSADT was predicted by lymph node involvement (p < 0.001) and Gleason grade (p = 0.06). Rapid PSADT also correlated with institution of postoperative adjuvant therapy (p = 0.003). Median biochemical RT for all patients was 6.7 months. Gleason grade and pathologic stage were found to be predictors of RT (p < 0.002). Postoperative PSADT did not correlate with RT (r = 0.08; p = 0.53). PSADT and RT were not different between Caucasian- versus African-Americans. CONCLUSIONS: These results serve to better characterize our cohort of patients who have evidence of biochemical recurrence after radical prostatectomy. Aggressiveness of recurrent disease (i.e. PSADT) seems to be predicted by lymph node involvement and higher pathologic grade. Furthermore, the lack of correlation of RT and PSADT suggests that early recurrences are not necessarily aggressive tumors: conversely, aggressive recurrences may occur at any point in the postoperative period. This information may aid in the postoperative treatment of recurrent disease and help to better define those patients who are at higher risk for developing clinical recurrence and who would benefit from greater vigilance during the postoperative period.  相似文献   
64.

Background and objective

To study the feasibility of a total endoscopic technique for selective neck dissection in oral cancers and to compare the technique with conventional open technique with a long cervical scar.

Methods

We included patients with early intraorally resectable squamous carcinomas and excluded patients whose primary lesion required reconstruction with microvascular flaps. We compared the following intraoperative parameters: cumulative length of the incision(s), duration of surgery, estimated blood loss, and intraoperative complications. The postoperative parameters included hospital stay, shoulder function, duration of analgesic use, and early postoperative complications. We used Shoulder Pain And Disability Index scores to assess shoulder function and assessed the oncologic outcome histopathologically by the number of nodes dissected.

Results

The mean operative time for minimally invasive supraomohyoid neck dissection (MISOND) was 53.7 ± 29.8 min, which was significantly longer than 39.4 ± 5.0 min for the open technique. The estimated blood loss in the MISOND group was significantly lower compared with the open technique (p < 0.001), and there were no major intraoperative complications in either group. Postoperative recovery assessed by hospital stay and time to resume routine work was slightly shorter in the MISOND group but not statistically significant. There were no reported early postoperative complications such as haemorrhage, wound dehiscence, or chyle leakage in either group. The mean Shoulder Pain And Disability Index score assessed 2 weeks postoperatively for the MISOND group was 14.35 ± 0.71 %, which was significantly better than 44.14 ± 1.18 % for the open technique (p < 0.001). The number of nodes dissected showed no significant difference between groups.

Conclusions

MISOND is a feasible and safe procedure with immediate oncologic outcomes comparable with those of conventional open SOND and provides better cosmetic and functional outcomes.
  相似文献   
65.
66.
Background: We describe a technique of U‐shaped bulboprostatic anastomosis for urethral injury after pelvic trauma. Methods: Sixty‐eight male patients were included in our study. Suprapubic cystostomy was carried out initially, followed by U‐shaped prostatobulbar anastomosis after 6–12 weeks. Follow ups were carried out at 6, 12 and 18 months by assessing patient satisfaction rates along with preoperative and postoperative urethrogram, uroflowmetry and labelled as good, fair and poor. The surgical technique used was as follows: after an inverted Y‐shaped skin incision, subcutaneous tissue and Colle’s fascia was opened. Bulbospongiosum was mobilized to gain access to the stricture membranous urethra, which was excised and the bulbar urethra freed. A sound was passed through the suprapubic cystostomy and complete resection of the scar over the tip of the sound was carried out. A silicon catheter was then passed into the bladder and the anastomosis was completed in a ‘U’ shape; that is, there were no stitches from the 10 to the 2 o’clock position. Results: Good and fair results were considered as successful. Overall success rate was 97.05% immediately and after 6 months, but decreased to 95.6% at 12 months and 93.6% at 18 months. Conclusion: U‐shaped end‐to‐end prostatobulbar anastomosis markedly decreases the chance of restenosis and impotence.  相似文献   
67.

Objective:

The aim of this work was to evaluate the quality of kilovoltage (kV) cone beam CT (CBCT) images acquired during arc delivery.

Methods:

Arc plans were delivered on a Catphan® 600 phantom (The Phantom Laboratory Inc., Salem, NY), and kV CBCT images were acquired during the treatment. The megavoltage (MV) scatter effect on kV CBCT image quality was evaluated using parameters such as Hounsfield unit (HU) accuracy, spatial resolution, contrast-to-noise ratio (CNR) and spatial non-uniformity (SNU). These CBCT images were compared with reference scans acquired with the same acquisition parameters without MV “beam on”. This evaluation was carried out for different photon beams (6 and 15 MV), arc types (half vs full arc), static field sizes (10 × 10 and 25 × 25 cm2) and source-to-imager distances (SID) (150 and 170 cm).

Results and Conclusion:

HU accuracy, CNR and SNU were considerably affected by MV scatter, and this effect was increased with increasing field size and decreasing photon energy, whereas the spatial resolution was almost unchanged. The MV scatter effect was observed to be more for full-rotation arc delivery than for half-arc delivery. In addition, increasing the SID resulted in decreased MV scatter effect and improved the image quality.

Advances in knowledge:

Nowadays, volumetric modulated arc therapy (VMAT) is increasingly used in clinics, and this arc therapy enables us to acquire CBCT imaging simultaneously. But, the main issue of concurrent imaging is the “MV scatter” effect on CBCT imaging. This study aims to experimentally quantify the effect of MV scatter on CBCT image quality.  相似文献   
68.
The development of bone‐rebuilding anabolic agents for potential use in the treatment of bone loss conditions, such as osteoporosis, has been a long‐standing goal. Genetic studies in humans and mice have shown that the secreted protein sclerostin is a key negative regulator of bone formation, although the magnitude and extent of sclerostin's role in the control of bone formation in the aging skeleton is still unclear. To study this unexplored area of sclerostin biology and to assess the pharmacologic effects of sclerostin inhibition, we used a cell culture model of bone formation to identify a sclerostin neutralizing monoclonal antibody (Scl‐AbII) for testing in an aged ovariectomized rat model of postmenopausal osteoporosis. Six‐month‐old female rats were ovariectomized and left untreated for 1 yr to allow for significant estrogen deficiency‐induced bone loss, at which point Scl‐AbII was administered for 5 wk. Scl‐AbII treatment in these animals had robust anabolic effects, with marked increases in bone formation on trabecular, periosteal, endocortical, and intracortical surfaces. This not only resulted in complete reversal, at several skeletal sites, of the 1 yr of estrogen deficiency‐induced bone loss, but also further increased bone mass and bone strength to levels greater than those found in non‐ovariectomized control rats. Taken together, these preclinical results establish sclerostin's role as a pivotal negative regulator of bone formation in the aging skeleton and, furthermore, suggest that antibody‐mediated inhibition of sclerostin represents a promising new therapeutic approach for the anabolic treatment of bone‐related disorders, such as postmenopausal osteoporosis.  相似文献   
69.
Congenital choledochal cysts in adults: twenty-five-year experience   总被引:3,自引:0,他引:3  
Background Choledochal cyst is rare in western countries. The relatively high incidence of coexistent hepatobiliary disease increases the difficulty of the surgical management of choledochal cyst. Here we analyze the diagnosis and treatment of congenital bile duct cyst in 122 Chinese adults. Methods The clinical data of 122 patients with congenital choledochal cysts admitted from 1981 to 2006 were analyzed. Results Clinical symptoms in most cases were nonspecific, resulting in delayed diagnosis. Sixty-one patients (50%) had coexistent pancreatobiliary disease. Among the 122 patients, 119 patients underwent ultrasonic examination; ERCP/MRCP was performed in 63 cases and CT in 102 cases. Abnormal pancreatobiliary duct junction was found in 48 patients. Sixteen patients had malignant lesions in the bile duct, arising in 11 of them from incomplete choledochal cyst that underwent various operations including cystenterostomy or cystojejunostomy. There was significant difference between the patients who underwent incomplete cyst resection and complete cyst resection in malignancy rate of bile duct (Chi square test, P= 0.000; odds ratio, 7.800; 95 % confidence interval, 2.450 to 24.836). Conclusions ERCP, CT and MRCP had proved their great values in the classification of the disease. Cyst excision with Roux-en-Y hepaticojejunostomy is recommended as the treatment of choice for patients with type I or type IV cysts. For type V cyst (Caroli’s disease) with recurrent cholangitis, liver transplantation should be considered.  相似文献   
70.
Neurilemmoma is usually soimry, benign tumour derived from schwan cells of the Sheaths of peripheral cranial or autonomie nerves. In thehead and neck region it occurs most commonly in association with acoustic nerve within the skuil and is rely fottnd in the oral cavity (1,2). We report here two cases of the iongue diagnosed on histopathohgy.  相似文献   
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