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91.
This best evidence topic in congenital cardiac surgery was written according to a structured protocol. The question addressed was whether the use of balloon atrial septostomy (BAS) before the arterial switch surgery for transposition of the great arteries (TGA) improved the final outcome. Altogether more than 251 papers were found using the reported search, of which 12 represented the best evidence to answer the clinical question. The search was further limited to recent articles since the results have improved compared with previous years, due to newer equipment and techniques. This narrowed the search to five papers that have focused on this issue since 2006 when a study of 29 term neonates identified BAS as major risk factor for focal brain injury and reinvigorated the debate of adverse neurological outcome especially in the context of the fact that total correction by the arterial switch procedure is routine in neonates now. Subsequently, a prospective study of 64 newborn infants followed by another study of 26 neonates with TGA, have shown no association between BAS and brain injury. Similarly, in a study of more than 2000 cases of dTGA, no association has been found between BAS and increased risk of clinical stroke either in the neonatal period or in follow-up hospitalizations. On the other hand, another nationwide data analysis of 8681 patients with TGA, has shown increased risk of stroke in patients undergoing BAS but it could only show association and not establish causation of the complication. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated.  相似文献   
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Previously described Doppler color flow mapping methods for estimating the severity of valvular regurgitation have focused on the distal jet. In this study, a newer Doppler color flow technique, focusing on the flow proximal to an orifice, was used. This method identifies a proximal isovelocity surface area (PISA) by displaying an aliasing interface. Volume flow rate (cm3/s) can be calculated as PISA (cm2) x aliasing velocity (cm/s). For planar circular orifices, a hemi-elliptic model accurately approximated the shape of PISA. Clinically, however, orifice shapes may be noncircular. In vitro flow experiments (n = 226) using orifices of various shapes (ellipse, square, triangle, star, rectangle) were performed. Volume flow rate calculated using a hemi-elliptic model for PISA was accurate, with average percent differences from actual flow rate = +4.3% for a square, -4.2% for a triangle, -4.7% for a star, -4.5% for an ellipse and -2.8% for a rectangle. However, average percent differences for calculated volume flow rates using a hemispheric model for PISA shape ranged from -11.6% (square) to -34.8% (rectangle). In addition, to evaluate whether PISA is influenced by machine factors, in vitro studies (n = 83) were performed.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Touraine–Solente–Gole syndrome, also known as Pachydermoperiostosis (PDP) or Primary Hypertrophic Osteoarthropathy, is a rare hereditary disorder, which affects both bones and skin. It is characterized by a combination of dermatologic changes (pachydermia or thickening of the skin) and rheumatologic manifestations (periostosis and finger clubbing). Eyelid ptosis which is caused by thickened eyelids (blepharoptosis) is a less common symptom. We report the case of a patient with a complete form of Touraine–Solente–Gole syndrome with bilateral blepharoptosis as presenting feature.  相似文献   
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Role of high resolution computerized tomography (HRCT) of temporal bone is established in cases of atticoantral chronic suppurative otitis media (CSOM) with intracranial complications. Routine use of HRCT in management of patients of atticoantral CSOM without intracranial complications has been an issue of debate. The aim of this study was to evaluate the routine use of HRCT of temporal bone in such cases. This study was a prospective study done at LG hospital, AMC MET Medical College, Ahmedabad to evaluate and compare the temporal bone findings in HRCT and intraoperative findings in 100 patients with atticoantral CSOM. All patients underwent HRCT screening followed by surgical exploration of middle ear cleft. In extent of disease HRCT showed very high sensitivity and specificity for epitympanum (100, 94%) and mesotympanum (98, 98%) areas. It gave valuable information of disease extent in hidden areas like sinus tympani and facial recess of mesotympanum. HRCT satisfactorily delineated malleus and incus erosion but had 75% sensitivity for detecting erosion of stapes suprastructure, though specificity was of 97%. For bony anatomical landmarks HRCT showed very high sensitivity and specificity for detecting erosion of lateral semicircular canal, tegmen tympani and sinus plate. Detection of facial canal erosion on HRCT had moderate sensitivity of 75%. We concluded that routine use of HRCT is justified as a reliable preoperative tool in patients with atticoantral CSOM without intracranial complications and it helps to plan type of surgical intervention. HRCT has limited role to distinguish between granulations and cholesteatoma and also to delineate stapes supra structure and facial nerve canal.  相似文献   
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Oculodentodigital dysplasia is a rare, autosomal dominant disorder with high penetrance and variable expressivity, caused by mutations in the connexin 43 or gap junction protein alpha-1 gene. It has been diagnosed in fewer than 300 people worldwide with an incidence of around 1 in 10 million. It affects many parts of the body, particularly eyes (oculo), teeth (dento), and fingers and/or toes (digital). The common clinical features include facial dysmorphism with thin nose, microphthalmia, syndactyly, tooth anomalies such as enamel hypoplasia, anodontia, microdontia, early tooth loss and conductive deafness. Other less common features are abnormalities of the skin and its appendages, such as brittle nails, sparse hair, and neurological abnormalities. To prevent this syndrome from being overlooked, awareness of possible symptoms is necessary. Early recognition can prevent blindness, dental problems and learning disabilities. Described here is the case of a 21-year-old male who presented to the ophthalmology outpatient department with a complaint of bilateral progressive loss of vision since childhood.  相似文献   
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BACKGROUNDEvidence supporting convalescent plasma (CP), one of the first investigational treatments for coronavirus disease 2019 (COVID-19), has been inconclusive, leading to conflicting recommendations. The primary objective was to perform a comparative effectiveness study of CP for all-cause, in-hospital mortality in patients with COVID-19.METHODSThe multicenter, electronic health records–based, retrospective study included 44,770 patients hospitalized with COVID-19 in one of 176 HCA Healthcare–affiliated community hospitals. Coarsened exact matching (1:k) was employed, resulting in a sample of 3774 CP and 10,687 comparison patients.RESULTSExamination of mortality using a shared frailty model, controlling for concomitant medications, date of admission, and days from admission to transfusion, demonstrated a significant association of CP with lower mortality risk relative to the comparison group (adjusted hazard ratio [aHR] = 0.71; 95% CI, 0.59–0.86; P < 0.001). Examination of patient risk trajectories, represented by 400 clinico-demographic features from our real-time risk model (RTRM), indicated that patients who received CP recovered more quickly. The stratification of days to transfusion revealed that CP within 3 days after admission, but not within 4 to 7 days, was associated with a significantly lower mortality risk (aHR = 0.53; 95% CI, 0.47–0.60; P < 0.001). CP serology level was inversely associated with mortality when controlling for its interaction with days to transfusion (HR = 0.998; 95% CI, 0.997–0.999; P = 0.013), yet it did not reach univariable significance.CONCLUSIONSThis large, diverse, multicenter cohort study demonstrated that CP, compared with matched controls, is significantly associated with reduced risk of in-hospital mortality. These observations highlight the utility of real-world evidence and suggest the need for further evaluation prior to abandoning CP as a viable therapy for COVID-19.FUNDINGThis research was supported in whole by HCA Healthcare and/or an HCA Healthcare–affiliated entity, including Sarah Cannon and Genospace.  相似文献   
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