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991.
992.

Background

The standard technique of Peribulbar block is to use 25 g 25 mm needle at the junction between the lateral one third and medial two third of the lower orbital rim in the infero-temporal quadrant of the orbit. Theoretically, insertion of longer needles increases the potential of injury to important structure; however, safety of the shorter needle had never been demonstrated. This study describes the anatomy of the orbital structures with magnetic resonance imaging (MRI) using the three-dimensional constructive interference in steady state (3D CISS) sequence to present a morphological basis for needle entry at 12.5 and 25 mm lengths. Statistical comparisons were performed at the 12.5 versus 25 mm depths. Statistical significance was indicated by P < 0.05.

Method

Fifty patients free of orbital pathology with normal axial length were selected for MRI with the 3D CISS sequence. Original axial and multiplanar image reconstruction (MPR) images were selected for image interpretation. Orbital structures were identified at 12.5 and 25 mm depths from the orbital rim to compare significant differences in anatomy between the two imaging planes at the expected needle depth and to assess the size of the globe and the orbit.

Results

The cross sectional area of the extraocular muscles were statistically significantly smaller at the 12.5 mm plane (P = 0.001). The area of inferotemporal fat was statistically significantly larger at the 12.5 mm plane (P = 0.033). There was no statistical difference in the inferonasal and superonasal fat areas at different depths (P = 0.34, P = 0.35 respectively). The size of the orbit and globe was significantly larger at 12.5 mm (P = 0.001). There was no difference between depths in the presence or absence of neurovascular bundles and supporting structures including the intramuscular septae.

Conclusion

There is a larger structure-free space at a depth of 12.5 mm than at 25 mm. Therefore, the inference is that a needle inserted in the infero-temporal zone to a depth of 12.5 mm is less likely to injure the eyeball or extra-ocular muscles than one advanced to 25 mm.  相似文献   
993.
BackgroundThe aims of this study are (1) to assess the association between body mass index (BMI) and failure to achieve the 1-year Knee Disability and Osteoarthritis Outcome Score-Physical Function Short Form (KOOS-PS) minimal clinically important difference (MCID) for total knee arthroplasty (TKA) patients and (2) to determine if there is a BMI threshold beyond which the risk of failing to achieve the MCID is significantly increased.MethodsA regional arthroplasty registry was queried for TKA patients from 2016 to 2019 with completion of preoperative and 1-year postoperative KOOS-PS. The MCID threshold was derived using a distribution-based approach. Demographic and patient-reported outcome measure variables were collected. BMI was analyzed continuously and categorically using cutoffs defined by the Centers for Disease Control and Prevention. The association between failure to achieve 1-year MCID and BMI was analyzed using multiple logistic regression. A BMI threshold was determined using the Youden index and receiver operating characteristic curve.ResultsIn total, 1059 TKAs were analyzed. BMI assessed continuously was significantly associated with failure to achieve the KOOS-PS MCID (odds ratio 1.03, 95% confidence interval 1.00-1.05, P = .025). Analysis of BMI categorically revealed that “overweight” (25-30 kg/m2), “obese class I” (30-35 kg/m2), “obese class II” (35-40 kg/m2), and “obese class III” (>40 kg/m2) patients faced 77%, 76%, 83%, and 106% greater risk, respectively, of failing to achieve the KOOS-PS MCID compared to “normal BMI” (<25 kg/m2) patients.ConclusionElevated BMI was associated with an increased risk of failure to achieve the 1-year KOOS-PS MCID following TKA.  相似文献   
994.
Abdominal Radiology - To assess changes in imaging and volume characteristics of the prostate gland by magnetic resonance (MR) following prostatic artery embolization (PAE) for benign prostate...  相似文献   
995.
BackgroundPM RMS represents a diagnostic and therapeutic problem as it is less visible than other superficial head and neck sites, and has tendency to local and intracranial extension.ObjectivesThe aim of this work is to study the treatment outcome, overall survival (OS) and event free survival (EFS) of pediatric PM RMS patients diagnosed and treated at the Children Cancer Hospital-Egypt [CCHE-57357] during a 4 year period.MethodsRetrospective review of charts of newly diagnosed pediatric PM RMS patients diagnosed and treated in CCHE during the period between July 2007 and the end of June 2011.ResultsForty-two pediatric patients with PM RMS with age ranging from 3 months to 17.7 years (median 6.9 years) were studied. The follow up period ranged from 4 to 55 months with a median of 24.8 months.Twenty-one patients [50%] were stage III, while 11 patients [26.1%] were stage IV.The 3-year overall survival (OS) was 58.4 ± 8.9%. OS was 65.9 ± 10% for non metastatic tumors while it was 35.8 ± 16.2% for the metastatic ones (p = 0.039).The 3-year event-free survival (EFS) was 48 ± 8.6% for the whole group. The non-metastatic and metastatic patients had 3-year EFS of 56.5 ± 9.7% and 24.9 ± 14.9% respectively. This difference was not statistically significant (p = 0.127).ConclusionPM RMS remains a diagnostic and therapeutic problem. Late presentation and advanced local disease compromise treatment options and decrease OS and EFS.  相似文献   
996.
Congenital diaphragmatic hernia (CDH) is a challenging condition. It is commonly associated with high mortality due to associated lung hypoplasia, pulmonary hypertension and co-existent anomalies. This review highlights recent progress in the perinatal management of CDH and addresses long term outcome issues for survivors indicating the need for multidisciplinary follow up.  相似文献   
997.

Objectives

To investigate the impact of insurance coverage on the adoption of customized individually made (CIM) knee implants and to compare patient outcomes and cost effectiveness of off-the-shelf and CIM implants.

Methods

A system dynamics simulation model was developed to study adoption dynamics of CIM and meet the research objectives. The model reproduced the historical data on primary and revision knee replacement implants obtained from the literature and the Nationwide Inpatient Sample. Then the dynamics of adoption of CIM implants were simulated from 2018 to 2026. The rate of 90-day readmission, 3-year revision surgery, recovery period, time savings in operating rooms, and the associated cost within 3 years of primary knee replacement implants were used as performance metrics.

Results

The simulation results indicate that by 2026, an adoption rate of 90% for CIM implants can reduce the number of readmissions and revision surgeries by 62% and 39%, respectively, and can save hospitals and surgeons 6% on procedure time and cut down cumulative healthcare costs by approximately $38 billion.

Conclusions

CIM implants have the potential to deliver high-quality care while decreasing overall healthcare costs, but their adoption requires the expansion of current insurance coverage. This work presents the first systematic study to understand the dynamics of adoption of CIM knee implants and instrumentation. More broadly, the current modeling approach and systems thinking perspective could be used to consider the adoption of any emerging customized therapies for personalized medicine.  相似文献   
998.
BACKGROUND There is risk of stenosis and thrombosis of the superior vena cava after upper extremity central catheter replacement. This complication is more serious among patients with single ventricle physiology, as it might preclude them from undergoing further life-sustaining palliative surgery.AIM To describe complications associated with the use of upper extremity percutaneous intravenous central catheters(PICCs) in children with single ventricle physiology.METHODS A single institution retrospective review of univentricular patients who underwent superior cavopulmonary anastomoses as their stage 2 palliation procedure from January 2014 until December 2018 and had upper body PICCs placed at any point prior to this procedure. Clinical data including ultrasonography, cardiac catheterization, echocardiogram reports and patient notes were used to determine the presence of thrombus or stenosis of the upper extremity and cervical vessels. Data regarding the presence and duration of upper extremity PICCs and upper extremity central venous catheter(CVC), and use of anticoagulation were recorded.RESULTS Seventy-six patients underwent superior cavopulmonary anastomoses, of which 56(73%) had an upper extremity PICC at some point prior to this procedure. Median duration of PICC usage was 24 d(25%, 75%: 12, 39). Seventeen patients(30%) with PICCs also had internal jugular or subclavian central venous catheters(CVCs) in place at some point prior to their superior cavopulmonary anastomoses, median duration 10 d(25%, 75%: 8, 14). Thrombus was detected in association with 2 of the 56 PICCs(4%) and 3 of the 17 CVCs(18%). All five patients were placed on therapeutic dose of low molecular weight heparin at the time of thrombus detection and subsequent cardiac catheterization demonstrated resolution in three of the five patients. No patients developed clinically significant venous stenosis.CONCLUSION Use of upper extremity PICCs in patients with single ventricle physiology prior to super cavopulmonary anastomosis is associated with a low rate of catheterassociated thrombosis.  相似文献   
999.
1000.
IntroductionSeverity of cholecystitis can be defined by the presence of histopathological changes such as gangrene, perforation, and empyema. Severe cholecystitis correlates with higher morbidity and longer hospital stay. The present review aimed to identify the predictors of severe cholecystitis.MethodsElectronic databases including PubMed, Scopus, and Cochrane library were searched in the period of January 1980 to March 2019. The main outcome of this review was to assess the predictability of pre-operative parameters such as Leukocytosis, fever, tachycardia, gallbladder wall edema, gallbladder distension, serum platelet count, and gallbladder mural striation. The role of patients’ characteristics including age, gender, and diabetes mellitus in predicting severe cholecystitis was also assessed.ResultsA total of 8823 patients were analysed. The mean age of patients was 67.14 ± 4.17. The parameters that had the highest Odds ratio in predicting severe cholecystitis were all findings on CT scanning and included attenuation of arterial phase, mural striation of the gallbladder, and decreased gallbladder wall enhancement.ConclusionWe conclude that CT findings were the most significant predictors of severe cholecystitis. Patients with clinical and laboratory predictors of severe cholecystitis should be urgently evaluated with contrast CT scan to rule out any severe complications  相似文献   
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