Risk of Down syndrome in neonates with duodenal obstruction or ... trisomy 21 (one from duodenal atresia, and the other from duodenal web). Thirty-nine ...
20th World Congress on Ultrasound in Obstetrics and Gynecology
OP09.05 Prenatal prediction of Down syndrome using prenasal thickness on second trimester ultrasound T. Ozcan, J. Allen, J. Peterson, K. Edell, P. Eggers, E. Pressman Department of Obstetrics and Gynecology, University of Rochester, Rochester, NY, USA Objectives: To assess the efficacy of prenasal thickness measurements on second trimester ultrasound examination in prenatal prediction of Down syndrome fetuses. Methods: Prenasal thickness was measured from stored fetal profile images during 16–24 week second trimester scans. Images from 115 women with normal fetuses and 15 women with Down syndrome were included. Prenasal thickness was measured as the shortest distance from the anterior edge of the lowest part of the frontal bone to the skin. Delta values for each gestational week for prenasal thickness were calculated for statistical analysis. Results: In the normal group prenasal thickness increased with gestation (prenasal thickness = −28.747 + (2.254 × GA, R2, P < 0.01). There was a statistically significant increase in the mean prenasal thickness measurement in Down syndrome fetuses. The prenasal thickness measurement was above the 95th centile in 66.7% (10/15) of all Down syndrome cases, including 4 of 5 with an absent nasal bone and 6 of 10 with a nasal bone length above 2.5 mm. Conclusions: Prenasal thickness is increased in fetuses with Down syndrome as compared to normal fetuses. Prenasal thickness may be an additional predictor for Down syndrome on the second trimester ultrasound.
OP09.06 Dimensions of the fetal facial profile in fetuses with absent nasal bone. Preliminary report ˜ 1 , C. Bucher1 , X. Flores1 , P. Romagnoli1 , F. Vinals R. Naveas2 , D. Silva3 , A. Giuliano1 1
Centro AGB Clinica Sanatorio Aleman, Concepcion, Chile; Facultad de Medicina y Enfermeria, Universidad San Sebastian, Concepcion, Chile; 3 Cesfam, Concepcion, Chile 2
Objectives: To determine if sonographic dimensions of the facial profile on a population of fetuses with absent nasal bone, differs from the normal population. Methods: 16 fetuses with absent nasal bone and with an adequate volume dataset of the fetal profile where included in the study. After a multi-planar manipulation to obtain a mid sagittal plane of the profile, 3 different operator measured the distance between the tip of the nose and the mouth (A), between the mouth and the gnathion (B), between the upper philtrum and the mouth (a) and between the mouth and the upper concavity of the chin (b), as recently reported by Goldstein et al, 2010. The values were plotted between the reported confidence limits, analyzing its percentage of distribution when it was corresponding or not to trisomy 21 (T21). Prenasal thickness was also measured. Wilcoxon non parametric test was used to determine differences between groups of measurement. Results: 2 cases were excluded (gestational age more than 26+6 weeks). The mean gestational age of the remaining was 21+3 (range, 18+2–26+5). 10/14 (71.5%) were carriers of T21 and the remaining were fetuses with normal karyotype. The A, B and (a) measurements were registered between the reported intervals of confidence, without statistical differences between both groups of fetuses with/without nasal bone. 60% of the fetuses with T21 had (b) measurement below the interval of confidence. The same measurement, on normal karyotype/absent nasal bone fetuses, were in the normal interval. Concordance between the three operators was found for the measurements, particularly (b). Mean prenatal thickness was 6.26 (T21) and 3.9 mm (non T21). Conclusions: Although the sample is small and ideally must be compared with our own population of healthy fetuses (study in
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Short oral presentation abstracts
course) it will be of interest to evaluate in future series the potential dysmorphism related to the distance between the mouth and the chin in fetuses carrying T21.
OP09.07 Risk of Down syndrome in neonates with duodenal obstruction or atrioventricular septal defects: is there a racial difference? E. S. Im1 , J. W. Park1 , B. J. Kim2 , C. W. Park1 , J. S. Park1 , J. K. Jun1 , H. C. Syn1 1
Obstetrics and Gynecology, Seoul National University Hospital, Seoul, Republic of Korea; 2 Obstetrics and Gynecology, Seoul National University Boramae Hospital, Seoul, Republic of Korea Objectives: Duodenal obstruction and atrioventicular septal defect are classic markers of Down syndrome. According to previous reports, trisomy 21 occurs in approximately 30% of neonates with duodenal obstruction and 40% of those with atrioventricular septal defect, respectively. However, on the basis of our clinical experience, it may be different in Korean population, especially who had duodenal obstruction. Therefore, we carried on a retrospective chart review to clarify our opinion. Methods: Forty-one cases of duodenal obstruction and 140 cases of atrioventricular septal defects were found at the Seoul National University Hospital from September 1999 to February 2010. Diagnosis was confirmed by surgery, postnatal echocardiography, or autopsy. Medical record of each case was reviewed retrospectively. Results: In 41 neonates with duodenal obstruction, two (4.9%) had trisomy 21 (one from duodenal atresia, and the other from duodenal web). Thirty-nine neonates were live-born, and they all underwent operations. According to operative finding, 26 had duodenal atresia, 9 had duodenal web, and 4 had annular pancreas. In 140 neonates with atrioventricular septal defect, forty-three (30.7%) had trisomy 21. Among them, 139 were live-born and 115 underwent operations. Conclusions: The occurrence of Down syndrome in cases with atrioventricular septal defect is similar to preexisting data, but that in those with duodenal obstruction is only one-sixth. Duodenal obstruction in Down syndrome is far less common in Korean (Asian) population than in western population. The significance of some antenatal sonographic markers for Down syndrome may be different among races or ethnic groups.
OP09.08 Second trimester amniocentesis is not a risk factor for very low birth weight (VLBW) and extremely low birth weight (ELBW) C. Cani, E. Bertucci, M. Pati, V. Fenu, S. Latella, V. Mazza Obstetrics and Gynecology, Modena University, Modena, Italy Objectives: To assess the risk of VLBW and ELBW attributable to second trimester amniocentesis. Methods: Records of 4,877 consecutive amniocentesis, performed between 1997–2003, were analyzed. Only VLBW and ELBW in the study population (exposed) and in the control group (unexposed) were evaluated. From this study were excluded 50 women (1% of the total) lost to follow up, 43 women that decided to terminate the pregnancy for fetal karyotypic abnormalities and 33 for a major malformations. Also fetal losses were excluded from the present study as previous published. Comparisons were made between the amniocentesis group versus non exposed. Odds ratios (OR) and 95% confidence intervals (95% CI) were calculated for VLBW and ELBW classes. Results: In the study population the VLBW were 35 (0.71%), ELBW were 20 (0.41%). In the control group the VLBW were 220 (0.67%) and the ELBW were 112 (0.34%). The odds ratios of the VLBW between the study and the control group did not show any statistical significant risk (OR = 1.07, 95% CI = 0.72–1.54). Also in ELBW
Ultrasound in Obstetrics & Gynecology 2010; 36 (Suppl. 1): 52–167
