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51.
52.

Background

Concerns have been raised regarding partial nephrectomy (PN) techniques that do not occlude the main renal artery.

Objective

Compare the perioperative outcomes of superselective versus main renal artery control during robotic PN.

Design, setting, and participants

A retrospective analysis of 121 consecutive patients undergoing robotic PN using superselective control (group 1, n = 58) or main artery clamping (group 2, n = 63).

Intervention

Group 1 underwent tumor-specific devascularization, maintaining ongoing arterial perfusion to the renal remnant at all times. Group 2 underwent main renal artery clamping, creating global renal ischemia.

Outcome measurements and statistical analysis

Perioperative and functional data were evaluated. The Pearson chi-square or Fisher exact and Wilcoxon rank sum tests were used.

Results and limitations

All robotic procedures were successful, all surgical margins were negative, and no kidneys were lost. Compared with group 2 tumors, group 1 tumors were larger (3.4 vs 2.6 cm, p = 0.004), more commonly hilar (24% vs 6%, p = 0.009), and more complex (PADUA 10 vs 8, p = 0.009). Group 1 patients had longer median operative time (p < 0.001) and transfusion rates (24% vs 6%, p < 0.01) but similar estimated blood loss (200 vs 150 ml), perioperative complications (15% vs 13%), and hospital stay. Group 1 patients had less decrease in estimated glomerular filtration rate at discharge (0% vs 11%, p = 0.01) and at last follow-up (11% vs 17%, p = 0.03). On computed tomography volumetrics, group 1 patients trended toward greater parenchymal preservation (95% vs 90%, p = 0.07) despite larger tumor size and volume (19 vs 8 ml, p = 0.002). Main limitations are the retrospective study design, small cohort, and short follow-up.

Conclusions

Robotic PN with superselective vascular control enables tumor excision without any global renal ischemia. Blood loss, complications, and positive margin rates were low and similar to main artery clamping. In this initial developmental phase, limitations included more perioperative transfusions and longer operative time. The advantage of superselective clamping for better renal function preservation requires validation by prospective randomized studies.

Patient summary

Preserving global blood flow to the kidney during robotic partial nephrectomy (PN) does not lead to a higher complication rate and may lead to better postoperative renal function compared with clamped PN techniques.  相似文献   
53.
54.

Background

Orthodontic palatal expansion appliances have been widely used with satisfactory and, most often, predictable clinical results. Recently, clinicians have successfully utilized micro-implants with palatal expander designs to work as anchors to the palate to achieve more efficient skeletal expansion and to decrease undesired dental effects. The purpose of the study was to use finite element method (FEM) to determine the stress distribution and displacement within the craniofacial complex when simulated conventional and micro-implant-assisted rapid palatal expansion (MARPE) expansion forces are applied to the maxilla. The simulated stress distribution produced within the palate and maxillary buttresses in addition to the displacement and rotation of the maxilla could then be analyzed to determine if micro-implants aid in skeletal expansion.

Methods

A three-dimensional (3D) mesh model of the cranium with associated maxillary sutures was developed using computed tomography (CT) images and Mimics modeling software. To compare transverse expansion stresses in rapid palatal expansion (RPE) and MARPE, expansion forces were distributed to differing points on the maxilla and evaluated with ANSYS simulation software.

Results

The stresses distributed from forces applied to the maxillary teeth are distributed mainly along the trajectories of the three maxillary buttresses. In comparison, the MARPE showed tension and compression directed to the palate, while showing less rotation, and tipping of the maxillary complex. In addition, the conventional hyrax displayed a rotation of the maxilla around the teeth as opposed to the midpalatal suture of the MARPE. This data suggests that the MARPE causes the maxilla to bend laterally, while preventing unwanted rotation of the complex.

Conclusions

In conclusion, the MARPE may be beneficial for hyperdivergent patients, or those that have already experienced closure of the midpalatal suture, who require palatal expansion and would worsen from buccal tipping of the teeth or maxillary complex.  相似文献   
55.
56.

Background

Dog bites are a frequent cause of facial and periocular injuries in both children and adults. This aim of this study is to review current practice in the management of facial and periorbital dog bite injuries and to examine the current evidence-base for such treatment strategies.

Methods

Five hundred eighty-seven patients with dog bite injuries requiring surgical intervention were identified from operating theatre records in one tertiary centre over a 9-year period. A retrospective case note review of 104 patients with facial and periorbital dog bite injuries was performed. Data on patient demographics, type of injury, treatment, and outcome was collected and analysed.

Results

The majority of patients were children, with a mean age of 11 years (range 1–91 years). Injuries involved the cheek in 57 cases (55 %), eyelids in 17 cases (16 %), lips in 24 cases (23 %) and nose in 8 cases (8 %). No facial fractures, canalicular, or globe injuries were recorded. All patients underwent irrigation, debridement, and primary wound closure. Surgical repair occurred within 24 h in 19 cases (18.2 %), within 48 h in 71 cases (68.3 %) and within 5 days in 14 cases (13.4 %). Three patients (2.9 %) developed a wound infection. Two patients (1.9 %) required scar revision surgery.

Conclusions

Periorbital and facial dog bite injuries may result in considerable morbidity. However, the majority of injuries are superficial and canalicular injury and bony injury is uncommon. Early wound irrigation, debridement and primary closure results in a good cosmetic outcome with a low risk of infection.

Level of Evidence:

Level IV, risk/prognostic study.  相似文献   
57.
58.
保证输血时血清学方面的安全,首要的是对受血者与献血者ABO血型定型,血清学检查通常分两个步骤.正定型通常使用鼠源单克隆抗体检测红细胞表面是否存在A或B抗原.互补的实验即反定型,利用当红细胞上缺乏A或B抗原时,人群可天然产生相对应的抗体的原理,检测血清中是否存在抗-A或者抗-B抗体.确定了受血者红细胞表面的ABO抗原以及血浆中的抗体,便能确定血型,为其提供相合的血液.  相似文献   
59.

Background

This paper reviews our experience with penetrating cervical venous trauma and aims to validate the selective non-operative management (SNOM) of these injuries.

Methods

This was a retrospective review of a prospectively maintained registry. All patients presenting alive with an injury to the internal jugular vein, subclavian vein or innominate vein following a PNI were reviewed for a 6-year period.

Results

Among 817 patients admitted for the management of PNI, 76 (9.3%) had a venous injury. Of these, 37 (48.7%) patients were managed non-surgically, 20 (26.3%) required immediate surgical exploration, seven of whom had an associated arterial injury, and 19 (25%) underwent surgery following a diagnostic CTA, 16 of whom had an associated arterial or aero-digestive injury. In total, only 16 (21.1%) of the 76 patients required exploration for venous injury alone. The majority (63.2%) of patients had a history of severe bleeding or hemodynamic instability prior to arrival, but only 20 (26.3%) required immediate exploration. Two (2.6%) patients died as a result of venous injury. No patients developed complications related to the venous injury.

Conclusions

SNOM is applicable to a well-defined subset of patients with isolated penetrating cervical venous trauma to the IJV and SCV identified on CTA.
  相似文献   
60.
Chronic low back pain is a major cause of disability and health care costs. Effective treatments are inadequate for many patients. Animal models are essential to further understanding of the pain mechanism and testing potential therapies. Currently, a number of preclinical models have been developed attempting to mimic aspects of clinical conditions that contribute to low back pain (LBP). This review focused on describing these animal models and the main behavioral tests for assessing pain in each model. Animal models of LBP can be divided into the following five categories: Discogenic LBP, radicular back pain, facet joint osteoarthritis back pain, muscle‐induced LBP, and spontaneous occurring LBP models. These models are important not only for enhancing our knowledge of how LBP is generated, but also for the development of novel therapeutic regimens to treat LBP in patients. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:1305–1312, 2018.
  相似文献   
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