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51.
Gregory A. Coté Michael Ansstas Somal Shah Rajesh N. Keswani Saad Alkade Sreenivasa S. Jonnalagadda Steven A. Edmundowicz Riad R. Azar 《Surgical endoscopy》2010,24(7):1752-1756
Background
Although the endoscopic management of bile leaks after cholecystectomy (CCY) is well established, the yield of a routine endoscopic retrograde cholangiogram (ERC) with a bile duct sweep at the time of stent removal is unclear. This study aimed to describe the prevalence of abnormal findings at follow-up ERC to determine whether upper endoscopy with stent removal and without cholangiography would suffice. 相似文献52.
53.
F. Wiesbauer C. Baytaroglu D. Azar H. Blessberger G. Goliasch S. Graf G. Mundigler R. Pacher G. Maurer T. Binder 《European journal of clinical investigation》2009,39(1):1-10
Background Cardiac resynchronization therapy (CRT) has been shown to reduce heart failure related morbidity and mortality. However, approximately 30% of patients do not respond to CRT. We investigated the usefulness of Echo Doppler parameters to predict reverse remodelling, functional improvement and mortality following CRT.
Materials and methods Our population consists of 200 consecutive heart failure patients evaluated for ventricular dyssynchrony by echocardiography between February 1999 and May 2007 who subsequently received CRT. Patients were reassessed for signs of reverse remodelling after a mean follow-up of 10 months. Information on vital status was obtained from local registration authorities.
Results Three parameters significantly predicted reverse remodelling in the logistic regression analysis: the Q-to-E-wave-delay (QED) at a cutoff of 550 ms (odds ratio 4·5, P -value 0·001), the interventricular mechanical delay (IVMD) at a cutoff of 60 ms (odds ratio 2·4, P -value 0·02), and the aortic electromechanical delay (A-EMD) at a cutoff of 140 ms (odds ratio 2·9, P -value 0·004). Furthermore, the QED and the IVMD also predicted all-cause mortality (hazard ratio 0·36, P -value 0·02 and 0·21, P -value 0·004, respectively). Adjustment for confounders did not alter the results.
Conclusions The QED and IVMD predict reverse remodelling and survival following CRT. These parameters are easy to obtain, provide valuable prognostic information, and should thus be measured in CRT candidates evaluated by echocardiography. 相似文献
Materials and methods Our population consists of 200 consecutive heart failure patients evaluated for ventricular dyssynchrony by echocardiography between February 1999 and May 2007 who subsequently received CRT. Patients were reassessed for signs of reverse remodelling after a mean follow-up of 10 months. Information on vital status was obtained from local registration authorities.
Results Three parameters significantly predicted reverse remodelling in the logistic regression analysis: the Q-to-E-wave-delay (QED) at a cutoff of 550 ms (odds ratio 4·5, P -value 0·001), the interventricular mechanical delay (IVMD) at a cutoff of 60 ms (odds ratio 2·4, P -value 0·02), and the aortic electromechanical delay (A-EMD) at a cutoff of 140 ms (odds ratio 2·9, P -value 0·004). Furthermore, the QED and the IVMD also predicted all-cause mortality (hazard ratio 0·36, P -value 0·02 and 0·21, P -value 0·004, respectively). Adjustment for confounders did not alter the results.
Conclusions The QED and IVMD predict reverse remodelling and survival following CRT. These parameters are easy to obtain, provide valuable prognostic information, and should thus be measured in CRT candidates evaluated by echocardiography. 相似文献
54.
Determination of corneal asphericity after myopia surgery with the excimer laser: a mathematical model. 总被引:6,自引:0,他引:6
PURPOSE. To determine the theoretical change of corneal asphericity within the zone of laser ablation after a conventional myopia treatment, which conforms to Munnerlyn's paraxial formula and in which the initial corneal asphericity is not taken into consideration. METHODS. The preoperative corneal shape in cross section was modeled as a conic section of apical radius R(1) and shape factor p(1). A myopia treatment was simulated, and the equation of the postoperative corneal section within the optical zone was calculated by subtracting the ablation profile conforming to a general equation published by Munnerlyn et al. The apical radius of curvature r(2) of the postoperative profile was calculated analytically. The postoperative corneal shape was fitted by a conic section, with an apical radius equal to r(2) and a shape factor p(2) equal to the value that induced the lowest sum of horizontal residuals and the lowest sum of squared residuals. These calculations were repeated for a range of different dioptric treatments, initial shape factor values, and radii of curvature to determine the change of corneal asphericity within the optical zone of treatment. RESULTS. Analytical calculation of r(2) showed it to be independent of the initial preoperative shape factor p(1). The determination of p(2) was unambiguous, because the same value induced both the lowest sum of residuals and the lowest sum of the squared residuals. For corneas initially prolate (p(1) < 1), prolateness increased (p(2) < p(1) < 1), whereas for oblate corneas (p(1) > 1), oblateness increased (p(2) > p(1) > 1) within the treated zone after myopia treatment. This trend increased with the increasing magnitude of treatment and decreased with increasing initial apical radius of curvature R(1). CONCLUSIONS. After conventional myopic excimer laser treatment conforming to Munnerlyn's paraxial formula, the postoperative theoretical corneal asphericity can be accurately approximated by a best-fit conic section. For initially prolate corneas, there is a discrepancy between the clinically reported topographic trend to oblateness after excimer laser surgery for myopia and the results of these theoretical calculations. 相似文献
55.
56.
During an 8-year period, oedema in the dorsal cervical region that produces a characteristic tremor on ballotement of the fetal head (nuchal oedema) was observed in 145 (7%) of the 2,086 fetuses that underwent karyotyping in our unit because of fetal malformations and/or growth retardation. Nuchal oedema was distinguished from nuchal cystic hygromata and from hydrops foetalis. In 132 (91%) of the cases with nuchal oedema, there were other fetal malformations, and 53 (37%) fetuses had chromosomal abnormalities, mainly trisomy 21 but also other trisomies, deletions or translocations, triploidy and Turner syndrome. Furthermore, the chromosomally normal fetuses with nuchal oedema had a very poor prognosis because, in many cases, there was an underlying skeletal dysplasia, a genetic syndrome or cardiac defect. 相似文献
57.
Complications after penetrating keratoplasty 总被引:2,自引:0,他引:2
58.
PURPOSE: To describe and compare the displacement of corneal flaps created during laser in situ keratomileusis (LASIK) procedures performed with two different microkeratomes and analyze parameters (for example, pupil-to-hinge distance, drift during suction) that might affect the flap displacement or be influenced by flap displacement. DESIGN: This work was based on a cross-sectional study design. METHODS: Images copied from video recordings of 206 consecutive LASIK surgeries were analyzed to determine the distance from pupil center to corneal flap hinge (pupil-to-hinge distance), the hinge size, the distance from the center of the pupil to the margins of the flap, and the positions of the suction ring before and after vacuum in corneal flaps created by the Hansatome and the Automated Corneal Shaper (ACS) microkeratomes. Accurate measurements of all these variables could be obtained in 121 eyes (Hansatome: n = 66, right eye (OD) = 27 eyes, left eye (OS) = 39 eyes; ACS: n = 55, OD = 25 eyes, OS = 30 eyes), which were included in the analysis. Formulas were derived to calculate from the measurements the magnitude and direction of the drift of the suction ring during vacuum and the final displacement of the corneal flap. RESULTS: The mean +/- standard deviation (SD) drift of eyes during suction with the Hansatome was 0.27 +/- 0.02 mm and with the ACS was 0.12 +/- 0.02 mm (P <.001). The Hansatome induced, on average, more biased (temporal vs random) drift than did the ACS. The mean final displacement of the center of the flap from the center of the pupil was of equal magnitude for the two instruments (0.37 +/- 0.02 mm and 0.36 +/- 0.02 mm with the Hansatome and ACS, respectively). CONCLUSION: The drift induced by the Hansatome contributes to the horizontal component of the final decentration of the corneal flaps. This tendency for drift and the resultant decrease in pupil-to-hinge distance should be considered to minimize flap displacements during LASIK. 相似文献
59.
Management of traumatic cataracts 总被引:3,自引:0,他引:3