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71.
Six cases were examined to review the important anaesthetic implications of Larsen's syndrome. Potential problems arising in these patients are highlighted and emphasis placed on cervical spine and airway/respiratory management. 相似文献
72.
Reliability of radiographic measurement of fracture angulation in children with femoral shaft fractures
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INTRODUCTION: Clinical decisions are based on x-ray measures of radiographs. However, the reliability of assessing the angular measurement of fractured femurs in children is unknown. The purpose of this study was to determine the intra- and interrater reliability of an x-ray assessment of femoral shaft fracture angulation in children. METHODS: On 2 occasions, 3 raters evaluated 30 radiographs of children aged 4 to 10 years, 3 to 24 months after a femoral fracture. The radiographs were evaluated by an orthopedic surgeon, an orthopedic fellow and a research assistant, using a standardized methodology. Reliability was assessed with the intraclass correlation coefficient (ICC), an index of concordance that ranges from 01, where > 0.75 indicates excellent concordance. RESULTS: The ICC for the intrarater ranged from 0.75 to 0.97. The interrater reliability ICC for anterior or posterior angulation was 0.91 (95% confidence interval [CI] 0.840.95) and for varus or valgus angulation was 0.90 (95% CI 0.790.95). A change in measurement of more than 5 degrees exceeds the variation in measurement and, therefore, can be attributed to a true shift in fracture position. CONCLUSIONS: With specific standardized protocols, radiographic assessment of femoral fractures is reliable, irrespective of the examiner's level of experience. 相似文献
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Whole-heart cine MRI using real-time respiratory self-gating. 总被引:1,自引:0,他引:1
Sergio Uribe Vivek Muthurangu Redha Boubertakh Tobias Schaeffter Reza Razavi Derek L G Hill Michael S Hansen 《Magnetic resonance in medicine》2007,57(3):606-613
Two-dimensional (2D) breath-hold cine MRI is used to assess cardiac anatomy and function. However, this technique requires cooperation from the patient, and in some cases the scan planning is complicated. Isotropic nonangulated three-dimensional (3D) cardiac MR can overcome some of these problems because it requires minimal planning and can be reformatted in any plane. However, current methods, even those that use undersampling techniques, involve breath-holding for periods that are too long for many patients. Free-breathing respiratory gating sequences represent a possible solution for realizing 3D cine imaging. A real-time respiratory self-gating technique for whole-heart cine MRI is presented. The technique enables assessment of cardiac anatomy and function with minimum planning or patient cooperation. Nonangulated isotropic 3D data were acquired from five healthy volunteers and then reformatted into 2D clinical views. The respiratory self-gating technique is shown to improve image quality in free-breathing scanning. In addition, ventricular volumetric data obtained using the 3D approach were comparable to those acquired with the conventional multislice 2D approach. 相似文献
76.
Derek J Dosdall Kang-An Cheng Jian Huang J Scott Allison James D Allred William M Smith Raymond E Ideker 《Heart rhythm》2007,4(6):758-765
BACKGROUND: Earliest recorded postshock myocardial activations in pigs originate in the subepicardium of the apex and lateral free wall of the left ventricle (LV) 30-90 ms after the shock. OBJECTIVE: The purpose of this study was to determine whether the Purkinje system is a candidate for the source of postshock activations by performing endocardial and transmural postshock activation mapping. METHODS: In five pigs, 32 plunge needles with 12 electrodes (1-mm spacing) were inserted into the LV apex and lateral free wall. Up to 70 plunge needles with six electrodes (2-mm spacing) were spread throughout the remainder of the LV, while 9-12 plunge needles with four electrodes (2-mm spacing) were inserted into the right ventricle. A basket catheter with 32 bipolar recording sites was inserted into the LV. Defibrillation-threshold (DFT)-level shocks were delivered during 10 episodes of electrically induced ventricular fibrillation. Electrograms of postshock activation cycles were analyzed for Purkinje and myocardial activations. RESULTS: Purkinje activations were recorded before local myocardial activation in 9% of basket electrograms and in 15% of plunge needles during the first postshock activation cycle. Purkinje activations were identified during the first and subsequent several postshock activation cycles in at least one basket and one needle electrogram in 96% and 98% of defibrillation episodes, respectively. CONCLUSIONS: The Purkinje system is active during the early postshock activation cycles after DFT-level shocks. Further studies are required to determine whether activation initiates in the Purkinje system or whether it is activated by the myocardium or by Purkinje-myocardial junctional cells. 相似文献
77.
Parish P Sedghizadeh Derek Wong Charles F Shuler Vincent Linz John R Kalmar Carl M Allen 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2007,104(2):e30-e34
The calcifying epithelial odontogenic tumor (CEOT), or Pindborg tumor, is a rare and benign odontogenic neoplasm that affects the jaw. The most common manifestation of CEOT is a unifocal or localized lesion of the involved jaw, which may appear clinically as a hard tissue swelling and radiographically as a mixed radiolucent-radiopaque mass. In this article, we present a unique case of CEOT affecting multiple sites in the maxilla and mandible of a 51-year-old white man. Though biopsy samples from all involved sites revealed similar histopathologic features consistent with CEOT, the fact that there was a multifocal presentation is an unusual phenomenon for CEOT and has never been reported. Multifocal odontogenic lesions are not typical but have been observed in conditions associated with known genetic mutations. For example, multiple odontogenic keratocysts are the most common feature of the inherited condition known as nevoid basal cell carcinoma syndrome. This case, however, is the first one to demonstrate that there may be a multifocal variant of CEOT that has not been previously recognized. 相似文献
78.
Background. Human immunodeficiency virus (HIV)-associated facial lipoatrophy is becoming epidemic and may seriously affect quality of life.
Objective. To review the possible causes and treatment options for HIV facial lipoatrophy.
Methods. This article is based on a review of the medical literature and the author's clinical experience in treating HIV facial lipoatrophy.
Conclusion. Although absorbable injectable fillers and implants are helpful in treating HIV facial lipoatrophy, they are limited by cost and the short duration of correction. Newer forms of longer-lasting fillers (poly-l-lactic acid [Sculptra]) and permanent injectable fillers (liquid injectable silicone) are proving useful for treatment of this condition. 相似文献
Objective. To review the possible causes and treatment options for HIV facial lipoatrophy.
Methods. This article is based on a review of the medical literature and the author's clinical experience in treating HIV facial lipoatrophy.
Conclusion. Although absorbable injectable fillers and implants are helpful in treating HIV facial lipoatrophy, they are limited by cost and the short duration of correction. Newer forms of longer-lasting fillers (poly-l-lactic acid [Sculptra]) and permanent injectable fillers (liquid injectable silicone) are proving useful for treatment of this condition. 相似文献
79.
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