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71.
Purpose  This prospective single-centre phase II trial assessed the diagnostic impact of 18F-FDG PET–CT in the evaluation of solid pancreatic lesions (∅ ≥10 mm) compared to endosonography (EUS), endoscopic retrograde cholangio-pancreatography (ERCP) with intraductal ultrasound (IDUS), abdominal ultrasound (US) and histopathological reference. Methods  Forty-six patients (32 men/14 women, ∅ 61.7 years) with suspected pancreatic neoplasms underwent PET–CT with contrast-enhanced biphasic multi-detector CT of the upper abdomen followed by a diagnostic work-up with EUS, ERCP with IDUS and US within 3 weeks. PET–CT data sets were analysed by two expert readers in a consensus reading. Histology from surgery, biopsy/fine-needle aspiration and/or clinical follow-up ≥12 months served as standard of reference. Results  Twenty-seven pancreatic malignancies were histopathologically proven; 19 patients had benign diseases: 36/46 lesions (78%) were detected in the head of the pancreas, 7/46 and 3/46 in the body and tail region, respectively. Sensitivity and specificity of PET–CT were 89% and 74%, respectively; positive predictive value (PPV) and negative predictive value (NPV) were 83% and 82%, respectively. Sensitivity (81–89%), specificity (74–88%), PPV (83–90%) and NPV (77–82%) achieved by EUS, ERCP and US were not significantly different. PET analysis revealed significantly higher maximum mean standardised uptake values (SUVmax 6.5 ± 4.6) in patients with pancreatic malignancy (benign lesions: SUVmax 4.2 ± 1.5; p < 0.05). PET–CT revealed cervical lymphonodal metastasis from occult bronchogenic carcinoma and a tubular colon adenoma with intermediate dysplasia on polypectomy, respectively. Conclusions   18F-FDG PET–CT achieves a comparably high diagnostic impact evaluating small solid pancreatic lesions versus conventional reference imaging modalities. Additional clinical diagnoses are derived from concomitant whole-body PET–CT imaging. Verena Schick and Christiane Franzius contributed equally to this work.  相似文献   
72.
OBJECTIVE: This article aims to summarize the available data on reducing radiation dose exposure in routine chest CT protocols. First, the general aspects of radiation dose in CT and radiation risk are discussed, followed by the effect of changing parameters on image quality. Finally, the results of previous radiation dose reduction studies are reviewed, and important information contributing to radiation dose reduction will be shared. CONCLUSION: A variety of methods and techniques for radiation dose reduction should be used to ensure that radiation exposure is kept as low as is reasonably achievable.  相似文献   
73.
PURPOSE: To investigate the effects of intravascular volume replacement therapy on the inflammatory response during major surgery. METHODS: Thirty-six patients scheduled for elective abdominal surgery were randomized to receive either 6% hydroxyethylstarch (130,000 Dalton mean molecular weight, degree of substitution 0.4; n = 18, HES-group) or lactated Ringer's solution (RL-group; n = 18) for intravascular volume replacement. Fluid therapy was given perioperatively and continued for 48 hr in the intensive care unit. Volume replacement was guided by physiological parameters. Serum concentrations of interleukin (IL)-6, IL-8 and IL-10 and soluble adhesion molecules (sELAM-1 and sICAM-1) were measured after induction of anesthesia, four hours after the end of surgery, as well as 24 hr and 48 hr postoperatively. RESULTS: Biometric and perioperative data, hemodynamics and oxygenation were similar between groups. On average, 4470 +/- 340 mL of HES 130/0.4 per patient were administered in the HES-group compared to 14310 +/- 750 mL of RL in the RL-group during the study period. Release of pro-inflammatory cytokines IL-6 and IL-8 was significantly lower in the HES-group [(peak values) 47.8 +/- 12.1 pg*dL(-1) of IL-6 and 35.8 +/- 11.2 pg*mL(-1) of IL-8 (HES-group) vs 61.2 +/- 11.2 pg*dL(-1) of IL-6 and 57.9 +/- 9.7 pg*mL(-1) of IL-8 (RL-group); P < 0.05]. Serum concentrations of sICAM-1 were significantly higher in the RL-group [(peak values) 1007 +/- 152 ng*mL(-1) (RL-group) vs 687 +/- 122 ng*mL(-1), (HES group); P < 0.05)]. Values of sELAM-1 were similar in both groups. CONCLUSION: Intravascular volume replacement with HES 130/0.4 may reduce the inflammatory response in patients undergoing major surgery compared to a crystalloid-based volume therapy. We hypothesize that this is most likely due to an improved microcirculation with reduced endothelial activation and less endothelial damage.  相似文献   
74.

Background

Large complex soft-tissue defects on the dorsum of the foot, with exposed tendons, joints, bones, nerves and vessels, have to be reconstructed by transplantation of free tissue grafts with good blood flow.

Patients and methods

Evaluation of 19 patients with an average age of 38 years who underwent closure of defects on the dorsum of the foot with free muscle flaps (with split-thickness skin grafts) in 14 cases and with free fasciocutaneous flaps in 5 is presented. In 10 patients a gracilis muscle flap was used, in 4 patients a latissimus dorsi flap, and in 2 patients a groin flap, while in 1 patient each an anterolateral thigh flap, an anteromedial thigh flap and a lateral arm flap was used. The aesthetic outcome was evaluated with reference to skin texture, pigmentation, thickness of the free flap and scar formation. The Stanmore system was used to determine the postoperative functional results.

Results

On average, patients were followed up for 29 months. We had no flap loss. A flap debulking procedure was performed in 6 patients. Better aesthetic results were obtained with muscle flaps plus skin graft than with fasciocutaneous flaps. Functional results were excellent in 6 patients, good in 5 and poor in 8 patients.

Conclusion

Free muscle flaps with skin grafts, particularly the free gracilis muscle flap, are superior to fasciocutaneous flaps and perforating flaps in aesthetic outcome and donor site morbidity.  相似文献   
75.
Background and aims Occurrence of tumor relapse is frequent in patients with pancreatic cancer despite the absence of residual tumor detectable at primary surgery and in histopathological examination. Therefore, it has to be assumed that current tumor staging procedures fail to identify minimal amounts of disseminated tumor cells, which might be precursors of subsequent metastatic relapse. The aim of this study was to assess the prognostic impact of minimal tumor cell spread detected in lymph nodes classified as “tumor-free” in routine histopathologic evaluation. Materials and methods A total of 154 “tumor-free” lymph nodes from 59 patients with pancreatic cancer who underwent intentionally curative tumor resection were examined by immunohistochemistry for disseminated tumor cells. Results Fifty (32.5%) of the “tumor-free” lymph nodes obtained from 36 (61%) patients displayed disseminated tumor cells. Multivariate survival analysis revealed that the presence of disseminated tumor cells in “tumor-free” lymph nodes is an independent prognostic factor for both a significantly reduced relapse-free survival (p = 0.03) and overall survival (p = 0.02). Conclusions The frequent occurrence and prognostic impact of immunohistochemically identifiable disseminated tumor cells in lymph nodes of patients with operable pancreatic cancer supports the need for a refined staging system of excised lymph nodes, which should include immunohistochemical examination.  相似文献   
76.
BACKGROUND: Paralytic pes calcaneus is commonly associated with myelomeningocele and continues to be one of the most difficult deformities to treat. The purpose of the present study is to describe and report the preliminary results of a new procedure to dynamically correct paralytic pes calcaneus. MATERIALS AND METHODS: Since 2002, the senior surgeon operated on six patients with myelomeningocele and developed a new procedure to dynamically correct paralytic pes calcaneus. This new procedure combines a complete tendon transfer (tibialis anterior and posterior, peroneus brevis and longus, and extensor digitorum and hallucis longus) to the Achilles tendon and an additive triple arthrodesis. The extent of the calcaneus deformity was evaluated by measuring the talocalcaneal angle. The mean followup was 32 months. RESULTS: Excellent results were achieved in five of the six patients with a mean age of 17.5 years. Using the American Orthopaedic Foot and Ankle Society (AOFAS) ankle and hindfoot scale, pain and function improved from an average of 41.6 preoperatively to 72.0 postoperatively. The deformity as assessed by the talocalcaneal angle, the calcaneal pitch, and the talometatarsal I angle improved after surgery significantly (p < 0.004). After 12 months, an additional surgery was required in two patients due to disabling drop-foot. CONCLUSION: This new surgical technique to correct paralytic pes calcaneus including complete tendon transfer and triple arthrodesis is promising. Although this is a technically demanding procedure, it provides an excellent functional result without the residual complications associated with ankle arthrodesis.  相似文献   
77.
BACKGROUND: Bile duct injury after hepatic artery thrombosis (HAT) in liver transplantation is believed to be caused by ischemia predominantly. We aimed to define the involvement of bile secretory dysfunction in the pathogenesis of liver injury after HAT. METHODS: In a murine model, the main hepatic artery, the extrahepatic peribiliary plexus, or both arterial connections to the liver were interrupted (n=5 for each group). After 1, 14, or 28 days, hepatobiliary function was assessed by analysis of bile transporter expression, serum bile acids and bilirubin, and hepatic ATP content. In addition, cellular injury was assessed by light microscopy and biochemical markers. RESULTS: There were no signs of hepatobiliary dysfunction or injury in sham-operated animals or in mice with interruption of the hepatic artery or the extrahepatic peribiliary plexus alone. However, as early as 24 hr after complete dearterialization, bile transporter expression was significantly reduced and intrahepatic cholestasis started to progress the following weeks. Histologic studies at 28 days after complete dearterialization showed severe hepatobiliary injury. CONCLUSIONS: This study indicates that arterial blood supply is critical for normal bile secretion. Bile duct injury after complete arterial deprivation is preceded by a loss of bile secretory function and subsequent intrahepatic cholestasis.  相似文献   
78.
There are various surgical techniques for the treatment of spinal fractures in the thoracolumbar region. Several implants have been developed for anterior or posterior instrumentation. Optimal treatment of unstable thoracolumbar osseous and ligamentous injuries remains controversial. To compare the stabilizing effects of an antero-lateral, thoracoscopically implantable plate system (macsTL, Aesculap, Germany) with the stability provided by a fixateur interne (SOCON, Aesculap, Germany), this in vitro investigation examined six human bisegmental (T12–L2) spinal units. Specimens were tested intact, and with simulation of osseous lesions in the anterior and ligamentous lesions in the posterior column (combined A/B-fracture). While loaded in the main anatomical planes such as flexion/extension, left and right lateral bending and left and right axial rotation with a bending moment of 7.5 Nm in a special testing jigs, motion analysis was performed. Quantitative interpretation of the stabilizing effect was achieved using a contactless three-dimensional motion analysis system. Each specimen was tested in four different scenarios: the first step measured movements of intact spinal segments. For the second step, specimens underwent simulation of combined A/B-fracture provided with bisegmental (T12/L2) antero-lateral fixation and bone strut graft from the iliac crest. For the third step, segments were additionally stabilized by the fixateur interne. The last measurement (fourth step) was performed after removing the anterior instrumentation. Range of motion (ROM) values were compared and statistically evaluated. Compared to the intact specimens the anterior instrumentation of the combined lesion, simulated A/B-fracture, leads to a stabilizing effect in flexion/extension and lateral bending. In contrast to these findings the torsional instability increased for the upper segment and bisegmentally. A maximum rigidity, beyond intact values, was registered for each anatomical plane with the combined instrumentation: antero-lateral and fixateur interne. After removing the anterior screw plate system maximum movements, in all segments for flexion/extension and lateral bending, bisegmentally and for the upper segment in axial rotation, were less than ROM values measured with the anterior system only. With respect to these findings a combined ventro-dorsal stabilization procedure should be considered for ligamentous disruptions of the posterior column in combination with A-fractures in the thoracolumbar junction.  相似文献   
79.
To determine and compare the influence of 2 different approaches on quadriceps femoris muscle function in total knee arthroplasty (TKA), 20 patients (14 women, 6 men) with bilateral knee osteoarthritis underwent a 1-stage bilateral TKA. Surgical approaches (subvastus, midvastus) were performed by a random selection. Measurements of quadriceps voluntary activation and maximal voluntary contraction were estimated by a twitch interpolation technique before, 3 and 6 months after TKA. Knee pain was quantified by the Lewis Score. There was no difference between the 2 approaches at 3 and 6 months after TKA with regard to maximal voluntary contraction (P = 0.84, F = 0.041) and voluntary activation (P = .863, F = 0.031). In the subvastus group was a significantly higher knee pain until 6 months after surgery (P = .02). The subvastus approach for TKA does not provide any advantages compared with the midvastus approach with respect to the quadriceps femoris muscle strength in the early postoperative period. Furthermore, the subvastus approach caused significantly more pain postoperatively.  相似文献   
80.
Complex reconstructive laparoscopic procedures in the field of urology such as radical prostatectomy and pyeloplasty have attracted increased attention in the past 2 years. However, extensive laparoscopic experience is required to master these procedures. Therefore, it remains questionable whether these techniques, which have been shown to be of profit to the patient in the hands of a specialist, will achieve widespread distribution. We have employed computer technology to bridge the gap between open surgery and laparoscopic access and used the daVinci Surgical System to establish laparoscopic radical prostatectomy as well as pyeloplasty and other retroperitoneal procedures at our institution. With experience of more than 70 procedures, we find that with the assistance of the daVinci Surgical System both radical prostatectomy and retroperiteoneal procedures can be easily translated from open to minimally invasive procedures with a considerably shorter learning curve and without compromising patient safety. We expect that large incisions will be soon a thing of the past in urologic surgery. Computer technology, together with mechanical engineering, will play a major role in enabling us to achieve better results despite minimal invasiveness.  相似文献   
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