You searched for:"Márcio Augusto Pinto de Ávila"
We found (4) results for your search.Summary
Revista Brasileira de Ginecologia e Obstetrícia. 1999;21(7):371-376
DOI 10.1590/S0100-72031999000700002
Purpose: to evaluate the possible value of pulsed and color Doppler of ductus venosus blood flow in the screening for chromosomal abnormalities at 10-14 weeks of gestation. Methods: the ductus venosus flow velocity waveforms and the nuchal translucency (NT) thickness were obtained immediately before the chorionic villus sample in 26 pregnancies. We employed the following criteria for the suspicion of chromosomal defects: reverse or absent flow during atrial contraction and NT greater or equal to 3 mm. We calculated the sensitivity, the specificity, the negative and positive predictive value for each of the above items. Results: there were 9 chromosomal abnormalities (3 cases of trisomy 21, 2 cases of trisomy 13, 1 case of trisomy 9, 1 case of trisomy 22, 1 triploidy and 1 monosomy X). Abnormal ductus venosus flow was observed in all cases (sensitivity of 100%). In the normal fetuses (17 cases) only 1 had abnormal flow (specificity of 94%). Concerning NT, the sensitivity and the specificity were 88% and 76%, respectively. Conclusion: our preliminary results suggest that the presence of chromosomal abnormalities may be strongly suspected when an increased NT thickness is associated with an absent or reverse flow in the ductus venosus. We speculated that both methods are valid in the screening of chromosomal defects.
Summary
Revista Brasileira de Ginecologia e Obstetrícia. 2001;23(5):291-298
DOI 10.1590/S0100-72032001000500004
Objective: to study the value of Doppler velocimetry of the ductus venosus and of the umbilical artery and vein, in the screening for chromosomal abnormalities at 10-14 weeks of gestation. Patients and Methods: a total of 314 fetuses were studied consecutively. In 112 cases a cytogenetic study was performed on material obtained from a biopsy of the chorionic villus, and in 202 cases the postnatal phenotype was used as a basis for the result. In addition to the routine ultrasonographic examination, all the fetuses were submitted to measurement of the nuchal translucency thickness and to Doppler velocimetry of the umbilical artery and vein, particularly of the ductus venosus. For statistical analysis the Fisher exact test and the Mann-Whitney test were used. Results: twenty-three cases of chromosomal abnormalities occurred. Of these abnormal cases, the ductus venosus blood flow during atrial contraction was absent (1 case) and reverse (22 cases), sensitivity was 92%. In the group of normal fetuses (289 cases), 6 evaluations demonstrated alterations in the Doppler of the ductus venosus (specificity of 97.6%, positive and negative predictive values of 76.7% and 93.3%, respectively); the false-positive rate was 2.4%. In reference to the umbilical vein and umbilical artery, there was no statistically significant difference between the abnormal and the normal group. Conclusion: The only parameter of Doppler velocimetry of the umbilical artery and vein which contributed to the detection of aneuploidies was the accidental discovery of the reverse blood flow in both vessels. Although our favorable results demonstrated that the Doppler velocimetry of the ductus venosus is effective in detecting aneuploidies, this conclusion, however, is preliminary and needs further investigation.
Summary
Revista Brasileira de Ginecologia e Obstetrícia. 2001;23(5):307-312
DOI 10.1590/S0100-72032001000500006
Purpose: to evaluate the effectiveness of color Doppler as a diagnosis method for polycystic ovary syndrome (PCOS) through blood flow variations in the ovarian stroma, in the uterine arteries and in the subendometrial tissue. Methods: thirty patients divided into two groups were selected: fifteen patients with amenorrhea or oligomenorrhea, hirsutism (Ferriman and Gallwey score >8), body mass index >25 kg/m² and echographic examination identifying increased hyperechogenic stromal and ovarian polycystosis (study group), and an identical number of patients presenting normal menstrual cycles, with no signs of hirsutism and with normal ultrasonography (control group). Transvaginal Doppler flowmetry measured systolic peak velocity or maximal velocity (Vmax) pulsatility index (PI) and resistance of ovarian stromal vessels, uterine arteries and subendometrial layer. Results: Doppler velocimetry showed significantly higher Vmax layer (p<=0,0004) in the ovarian stromal of patients with PCOS (12.2 cm/s) when compared to the control group (8.05 cm/s); the uterine artery PI was also higher in the PCOS group (3.3 cm/s) versus the control group (2.7 cm/s); other Doppler velocimetry parameters did not show significant differences. As we established a cutoff = 9 cm/s for the sample for Vmax, we obtained the percentages of 95.2 for sensitivity, 80.0 for specificity, 83.3 for positive predictive value and 94.1 for negative predictive value. Conclusion: Doppler velocimetry might constitute an additional tool to be incorporated in clinical and ultrasonographic investigation concerning the PCOS diagnosis.