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1.
To determine percent of patients without malignancy and ≤ 40 years of age with high cumulative radiation doses through recurrent CT exams and assess imaging appropriateness. From the cohort of patients who received cumulative effective dose (CED) of ≥ 100 mSv over a 5-year period, a sub-set was identified with non-malignant disease. The top 50 clinical indications leading to multiple CTs were determined. Clinical decision support (CDS) system scores were analyzed using a widely adopted standard of 1–3 (red) as “not usually appropriate,” 4–6 (yellow) “may or may not be appropriate,” and 7–9 (green) “usually appropriate.” Clinicians reviewed patient records to assess compliance with appropriate use criteria (AUC). 9.6% of patients in our series were with non-malignant conditions and 1.4% with age ≤ 40 years. CDS scores (rounded) were 2% red, 38% yellow, 27% green, and 33% unscored CTs. Clinical society guidelines for CT exams, wherever available, were followed in 87.5 to 100% of cases. AUCs were not available for several clinical indications as also referral guidelines for serial CT imaging. More than half of CT exams were unrelated to follow-up of a primary chronic disease. We are faced with a situation wherein patients in age ≤ 40 years require or are thought to require many CT exams over the course of a few years but the radiation risk creates concern. There is a fair number of conditions for which AUC are not available. Suggested solutions include development of CT scanners with lesser radiation dose and further development of appropriateness criteria.  相似文献   
2.
Haemophilia is a common cause of genetically inherited bleeding disorders. Pseudotumours occur in 1–2 % of persons with severe forms of haemophilia. These are a result of repeated haemorrhage into soft tissues, subperiosteum or a site of bone fracture with inadequate resorption of the extravasated blood. There are a number of therapeutic alternatives for this dangerous condition: surgical removal, percutaneous management, irradiation, embolization etc. In this case report, we describe the natural history, clinical course and successful surgical management of a patient with haemophilia who presented with a massive pseudotumour. We also briefly review the relevant literature on the various therapeutic modalities that have been implemented in the management of this rare complication. Though surgeons may be averse to operate on haemophiliacs, primary surgical management as done in our case may prove to be the definitive treatment option for such patients.  相似文献   
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This work presents the first sodium MRI functional renal study on a mouse model. The tissue sodium concentration was monitored during induced diuresis with furosemide. By using density-weighted chemical shift imaging (DWCSI) at high field strength a temporal resolution of less than 5 min for three dimensional (3D) data sets with high spatial resolution was achieved. A maximum increase of 20% in the cortex and a decrease of 45% of the original signal strength in the medulla were observed. These findings correspond well with experiments conducted on much larger rodent models.  相似文献   
5.
Techniques have been developed to culture bovine or porcine vascular cells on polyglycolic acid (PGA) scaffolds to form engineered vessels. Previously, it was shown that smooth muscle cells (SMCs) that were in close proximity to PGA remnants after 8 weeks of culture had lower expression of SMC markers of differentiation and were more mitotic compared with SMCs that were distant from polymer residuals. Modifications of PGA were explored as a means to minimize residual polymer fragments after culture. To hasten degradation, polymer was treated with heat, NaOH, or gamma-irradiation. Differential scanning calorimetry, mass and tensile strength degradation, and inherent viscosity were used to assess polymer characteristics. When polymer was maintained in aqueous conditions, tensile strength of treated PGA degraded to zero within 3 weeks for each treatment. Engineered vessel constructs cultured on NaOH and gamma-treated polymer displayed smooth muscle alpha-actin throughout the vessel wall. Scaffold treatment impacted graft morphology, cellular differentiation, and mechanical integrity.  相似文献   
6.
Current digital information systems in radiology are insufficient to accommodate the retrieval needs of academicians. Significant efforts are required in retrieving clinical cases for teaching and research. We describe a prototype system that supports intelligent case retrieval based on a combined specification of patient demographics, radiologic findings, and pathologic diagnoses. The documents for these cases can be distributed among multiple heterogeneous data bases. The system features automatic indexing of radiology and pathology reports, a comprehensive lexicon for thoracic radiology, an interface to a hospital information system, radiology information system, and picture archiving and communication systems, and a graphical user interface for query formulation and results visualization. The prototype system was developed within the domain of thoracic radiology involving patients with lung cancer.  相似文献   
7.
A Duarte variant with clinical signs.   总被引:2,自引:1,他引:2       下载免费PDF全文
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Supracondylar humerus fractures are the most common fractures around the elbow in children between 4 and 10 years of age. The treatment of supracondylar humerus fractures can vary from conservative treatment to operative treatment depending on the fracture type. All around the world, the most commonly used classification system is the Wilkins-modified Gartland classification of supracondylar humerus fractures. Currently, the decision to operate or conserve the fracture is taken on basis of this classification system. Non-operative treatment for type I fractures and operative treatment for type III fractures have been well-established in literature. The management of type II supracondylar humerus fracture creates confusion in the minds of numerous orthopaedic surgeons around the world. We have tried addressing this using a classification-based treatment algorithm. Other classification systems like the AO classification, Lagrange and Rigault classification and Bahk classification with special reference to special fracture patterns that require attention and pre-op planning have also been mentioned. It is important to understand that operative management of each supracondylar humerus fracture is unique as regards fixation method and it is important to consider the fracture pattern before internal fixation.  相似文献   
10.
PurposeThere is a known association between Cornelia de Lange syndrome (CdLS) and congenital diaphragmatic hernia (CDH), with CDH being the cause of death in 5%–20% of CdLS cases. We aimed to identify and describe patients with CDLS and CDH. We hypothesized that CdLS would be associated with high-risk CDH and poor outcomes.MethodsCDH Study Group patients from 1995 to 2019 were included. Those with CdLS were reviewed retrospectively. Rates of repair and outcomes were compared between patients with and without CdLS.ResultsWe identified 9,251 CDH patients. Of those, 21 had confirmed CdLS. CdLS patients had a lower birth weight (2.2 ± 0.57 kg) than non-CdLS patients (2.9 ± 0.64 kg) (p < 0.001). 5-min Apgar scores were lower in CdLS patients (6, 4–7) than non-CdLS patients (7, 5–8) (p = 0.014). Only 33% of CdLS patients underwent diaphragmatic repair compared to 84.2% of non-CdLS patients (p < 0.001). Mortality was 76% for CdLS patients compared with 29% for non-CdLS patients (p < 0.001). Of the 7 CdLS patients who underwent repair, 5 survived to hospital discharge.ConclusionsInfants with CdLS and CDH have a poor prognosis. However, CdLS patients who undergo repair can survive to discharge; therefore, the concomitant diagnosis of CdLS and CDH is not necessarily a contraindication to repair. Early recognition of these anomalies can assist with counseling and prognostication.Type of studyRetrospective comparative studyLevel of evidenceIII  相似文献   
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