Placenta Accreta: Spectrum of US and MR Imaging Findings
ABSTRACT Placenta accreta (PA) encompasses various types of abnormal placentation in which chorionic villi attach directly to or invade the myometrium. PA is a significant cause of maternal morbidity and mortality and is now the most common reason for emergent postpartum hysterectomy. Its prevalence has risen tenfold in the United States over the past 50 years, primarily due to the increasing percentage of pregnant patients undergoing primary and repeat cesarean sections. Placenta previa and previous cesarean section are the two most important known risk factors for PA. Accurate prenatal identification of affected pregnancies allows optimal obstetric management. Ultrasonography (US) remains the diagnostic standard, and routine US examination at 18-20 weeks gestation affords an ideal opportunity to screen for the disorder. Placental lacunae and abnormal color Doppler imaging patterns are the most helpful US markers for PA. In recent years, there has been increased interest in magnetic resonance (MR) imaging for the evaluation of PA, since it can provide information on depth of invasion and more clearly depict posterior placentas. The most reliable MR imaging findings are uterine bulging, heterogeneous placenta, and placental bands. Focal interruptions in the hypointense myometrial border may also be helpful. PA is a clinical and diagnostic challenge that is being encountered with increasing frequency. Clinicians should be aware of the clinical issues, risk factors, and imaging findings associated with PA to facilitate optimal case management.
Conference Paper: FIELDS-finite element design software[Show abstract] [Hide abstract]
ABSTRACT: A computer program called FIELDS (finite element design software) for the analysis of electric, magnetic, and thermal problems has been developed. The main programming language used is Fortran, with utility routines written in C and assembler. The total program size is in excess of 5000 lines. The goal of this project was to design a user-friendly, two-dimensional finite-element analysis package for IBM PC/XT. Users of the program need not understand the equations or algorithms involved. It is concluded that this program provides a low-cost alternative to mainframe computer-aided designProgrammable Control and Automation Technology Conference and Exhibition, 1988. Conference Proceedings., Fourth Annual Canadian; 11/1988
Conference Paper: Real gas flow characterization in the ONERA F4 high enthalpy wind tunnel[Show abstract] [Hide abstract]
ABSTRACT: The ONERA F4 Hot Shot wind tunnel provides hypersonic air flows at high enthalpy and high pressure total conditions. In such a wind tunnel, real gas effects are large yielding experimental difficulties to assess the test section free stream characteristics. Flow contamination was a problem for total enthalpy determination when using the first arc chamber configuration, made of copper and organic materials. This point has been dramatically improved with the new arc chamber made of carbon materials. Test section free stream knowledge is achieved by direct means involving optical techniques and by indirect means, i.e. through the numerical rebuilding of experiments on nozzle and standard model flows. The free stream flow is observed to be close to equilibrium on data like pressure or translational temperature, while nitric oxide (NO) concentration measurement is rather close to a nonequilibrium situation. The possibility to model such results is discussed. Finally, example example of force measurements on a capsule model is given to compare real gas with perfect gas resultsInstrumentation in Aerospace Simulation Facilities, 1997. ICIASF '97 Record., International Congress on; 01/1997
- Annales d Endocrinologie 10/2006; 67(5):448-448. DOI:10.1016/S0003-4266(06)72774-3 · 0.66 Impact Factor