Official Proceedings - AIUM

American Institute of Ultrasound in Medicine Proceedings J Ultrasound Med 32(suppl):S1–S134, 2013.05) and demonstrated a trend toward a lower BPD and FTD (P < .1) comparedto OMT patients.Conclusions—Prenatal ultrasound evaluation of the CCD andTCD correlate with biomarker-proven PAE. These results indicate that ultrasoundparameters may be helpful in conjunction with other diagnostic indicesin detecting PAE. Future studies need to examine the predictive utilityof ultrasound indices on neurodevelopmental outcomes in children with PAE.1521317 Effect of Maternal Body Mass Index on Fetal Growth: Useof Individualized Growth Assessment and 2-Level ModelingTimothy Canavan, 1 * Russell Deter 2 1 Obstetrics, Gynecology,and Reproductive Sciences, University of Pittsburgh–Magee Women’s Hospital, Pittsburgh, Pennsylvania USA;2Obstetrics and Gynecology, Baylor College of Medicine,Houston, Texas USAObjectives—To determine the effect of the maternal body massindex (BMI) on fetal biometry estimates of growth using individualgrowth assessment (IGA) and 2-level linear modeling.Methods—A retrospective review of serial biometry in the secondand third trimesters from 246 normal term singleton fetuses was performed.Four to 8 biparietal diameter (BPD), head circumference (HC),abdominal circumference (AC), and femur diaphysis length (FDL) measurementsper fetus were available and used to determine second-trimestergrowth rates. Expected third-trimester size trajectories were generatedfrom these data and percent deviations (%Dev = [{observed – expected}/expected] × 100) were calculated. Two-level linear modeling was used todetermine individual %Dev slopes and the effect of BMI on these slopes.Relationships between individual second- and third-trimester slopes andBMI values were also evaluated using regression analysis.Results—Linear regression analysis of second-trimester growthindicated no significant relationships between the fetal growth rate andthe BMI (adjusted R 2 = 0.0%–1.0% except for AC in 1 subgroup [5.6%]).With third-trimester %Dev slopes, there was a definite BMI effect for HC,but only a marginal effect was seen for AC (critical value = 1.98; t = 2.00).There was no BMI effect on BPD or FDL slopes. Regression analysis indicatedno significant relationships (adjusted R 2 = 0%–0.2%) betweenBMI values and third-trimester %Dev slopes for any anatomic parameter.Conclusions—Our findings support the premise that the maternalBMI does not alter fetal growth in either the second or thirdtrimester. It also demonstrates that IGA and 2-level linear modeling, usedtogether, can assess the effect of an extrinsic factor on fetal growth.1541336 Cerebral Autoregulation in Normal PregnancyTeelkien van Veen, 1 * Sina Haeri, 2 Rodrigo Ruano, 2 RonnyPanerai, 3 Gerda Zeeman, 1,4 Michael Belfort 2 1 Obstetrics andGynecology, University Medical Center Groningen, Groningen,the Netherlands; 2 Obstetrics and Gynecology, BaylorCollege of Medicine, Houston, Texas USA; 3 CardiovascularSciences, University of Leicester, Leicester Royal Infirmary,Leicester, England; 4 Obstetrics and Gynecology, Erasmus MedicalCenter, Rotterdam, the NetherlandsObjectives—Recent advances in transcranial Doppler (TCD)methodology now allow direct real-time estimation of the functional state ofcerebral autoregulation. Since no normative data exist for pregnant patients,our aim was to establish baseline data for cerebral autoregulation in healthypregnancy against which women with disease states can be compared.Methods—In this prospective cohort analysis, cerebral bloodflow velocity (CBFV) in the middle cerebral artery (using TCD), bloodpressure (using noninvasive continuous plethysmography), and end–tidalcarbon dioxide (etCO 2) were simultaneously evaluated at baseline andduring voluntary breath holding (increased etCO 2). The transfer functionparameters (gain, phase, and coherence in the low-frequency range [