doppler Archives - Page 2 of 2 - Revista Brasileira de Ginecologia e Obstetrícia
Summary
Revista Brasileira de Ginecologia e Obstetrícia. 2011;33(4):157-163
DOI 10.1590/S0100-72032011000400002
PURPOSE: to determine the best Doppler flow velocimetry index to predict small infants for gestational age (SGAI), in pregnant women with hypertensive syndromes. METHODS: a cross-sectional study was conducted enrolling 129 women with high blood pressure, submitted to dopplervelocimetry up to 15 days before delivery. Women with multiple fetuses, fetal malformations, genital bleeding, placental abruption, premature rupture of fetal membranes, smoking, use of illicit drugs, and chronic diseases were excluded. A receiver operating characteristic (ROC) curve for each Doppler variable was constructed to diagnose SGAI and the sensitivity (Se), specificity (Sp), positive (PLR) and negative (NLR) likelihood ratio were calculated. RESULTS: the area under the ROC curve for the middle cerebral artery resistance index was 52% (p=0.79) with Se, Sp, PLR, and NLR of 25.0, 89.1, 2.3 and 0.84% for a resistance index lower than 0.70, respectively. While the area under the ROC curve for the resistance index of the umbilical artery was 74% (p=0.0001), with Se=50.0%, Sp=90.0%, PLR=5.0 and NLR=0.56, for a resistance index higher or equal to 0.70. The area under the ROC curve for the resistance index umbilical artery/middle cerebral artery ratio was 75% (p=0.0001). When it was higher than 0.86, the Se, Sp, PLR and NLR were 70.8, 80.0, 3.4 and 0.36%, respectively. For the resistance index of the middle cerebral artery/uterine artery ratio, the area under the ROC curve was 71% (p=0.0001). We found a Se=52.2%, Sp=85.9%, PLR=3.7 and NLR=0.56, when the ratio was lower than 1.05. When we compared the area under the ROC curve of the four dopplervelocimetry indexes, we observed that only the resistance index umbilical artery/middle cerebral artery, resistance index middle cerebral artery/uterine artery and resistance index umbilical artery ratios seem to be useful for the prediction of SGA. CONCLUSION: in patients with high blood pressure during pregnancy, all dopplervelocimetry parameters, except the middle cerebral artery resistance index, can be used to predict SGAI. The umbilical artery/middle cerebral artery ratio seems to be the most recommended one.
Summary
Revista Brasileira de Ginecologia e Obstetrícia. 2011;33(4):157-163
DOI 10.1590/S0100-72032011000400002
PURPOSE: to determine the best Doppler flow velocimetry index to predict small infants for gestational age (SGAI), in pregnant women with hypertensive syndromes. METHODS: a cross-sectional study was conducted enrolling 129 women with high blood pressure, submitted to dopplervelocimetry up to 15 days before delivery. Women with multiple fetuses, fetal malformations, genital bleeding, placental abruption, premature rupture of fetal membranes, smoking, use of illicit drugs, and chronic diseases were excluded. A receiver operating characteristic (ROC) curve for each Doppler variable was constructed to diagnose SGAI and the sensitivity (Se), specificity (Sp), positive (PLR) and negative (NLR) likelihood ratio were calculated. RESULTS: the area under the ROC curve for the middle cerebral artery resistance index was 52% (p=0.79) with Se, Sp, PLR, and NLR of 25.0, 89.1, 2.3 and 0.84% for a resistance index lower than 0.70, respectively. While the area under the ROC curve for the resistance index of the umbilical artery was 74% (p=0.0001), with Se=50.0%, Sp=90.0%, PLR=5.0 and NLR=0.56, for a resistance index higher or equal to 0.70. The area under the ROC curve for the resistance index umbilical artery/middle cerebral artery ratio was 75% (p=0.0001). When it was higher than 0.86, the Se, Sp, PLR and NLR were 70.8, 80.0, 3.4 and 0.36%, respectively. For the resistance index of the middle cerebral artery/uterine artery ratio, the area under the ROC curve was 71% (p=0.0001). We found a Se=52.2%, Sp=85.9%, PLR=3.7 and NLR=0.56, when the ratio was lower than 1.05. When we compared the area under the ROC curve of the four dopplervelocimetry indexes, we observed that only the resistance index umbilical artery/middle cerebral artery, resistance index middle cerebral artery/uterine artery and resistance index umbilical artery ratios seem to be useful for the prediction of SGA. CONCLUSION: in patients with high blood pressure during pregnancy, all dopplervelocimetry parameters, except the middle cerebral artery resistance index, can be used to predict SGAI. The umbilical artery/middle cerebral artery ratio seems to be the most recommended one.
Summary
Revista Brasileira de Ginecologia e Obstetrícia. 2008;30(1):5-11
DOI 10.1590/S0100-72032008000100002
PURPOSE: to study the value of Doppler velocimetry of the ductus venosus, between the 11th and 14th weeks of pregnancy, associated to the nuchal translucency thickness measurement, in the detection of adverse fetal outcome. METHODS: a transversal and prospective study in which a total of 1,268 fetuses were studied consecutively. In 56 cases, a cytogenetic study was performed on material obtained from a biopsy of the chorionic villus and, in 1,181 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 ductus venosus. Aiming at prevalence and accuracy indices, sensitivity, specificity, positive predictive value, negative predictive value, probability of false-positive, probability of false-negative, reason of positive probability and reason of negative probability were calculated and analyzed. RESULTS: from the total of 1,268 fetuses, 1,183 cases were selected for analysis. From this number, 1,170 fetuses were normal (98.9%) and 13 fetuses presented adverse outcome at birth (1.1%), including fetal death (trisomy 21 and 22) in two cases; genetic syndrome (Nooman) in one case; two cases of polymalformed fetuses; cardiopathy in three cases; and other structural defects in five cases. The prevalence of the modified ductus venosus (wave A zero/reverse) in the studied population was of 14 cases (1.2%), with a false-positive rate of 0.7%. CONCLUSIONS: there is a significant correlation between the alteration of the ductus venosus Doppler velocimetry and the thickness of the nuchal translucency as an ultrasonographic marker for the first trimester of gestation, in the detection of adverse fetal outcome, especially serious malformations. The ductus venosus was able to diminish the false-positive result in comparison to the isolated use of the nuchal translucency thickness, improving considerably the positive predictive value of the test.
Summary
Revista Brasileira de Ginecologia e Obstetrícia. 2008;30(1):5-11
DOI 10.1590/S0100-72032008000100002
PURPOSE: to study the value of Doppler velocimetry of the ductus venosus, between the 11th and 14th weeks of pregnancy, associated to the nuchal translucency thickness measurement, in the detection of adverse fetal outcome. METHODS: a transversal and prospective study in which a total of 1,268 fetuses were studied consecutively. In 56 cases, a cytogenetic study was performed on material obtained from a biopsy of the chorionic villus and, in 1,181 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 ductus venosus. Aiming at prevalence and accuracy indices, sensitivity, specificity, positive predictive value, negative predictive value, probability of false-positive, probability of false-negative, reason of positive probability and reason of negative probability were calculated and analyzed. RESULTS: from the total of 1,268 fetuses, 1,183 cases were selected for analysis. From this number, 1,170 fetuses were normal (98.9%) and 13 fetuses presented adverse outcome at birth (1.1%), including fetal death (trisomy 21 and 22) in two cases; genetic syndrome (Nooman) in one case; two cases of polymalformed fetuses; cardiopathy in three cases; and other structural defects in five cases. The prevalence of the modified ductus venosus (wave A zero/reverse) in the studied population was of 14 cases (1.2%), with a false-positive rate of 0.7%. CONCLUSIONS: there is a significant correlation between the alteration of the ductus venosus Doppler velocimetry and the thickness of the nuchal translucency as an ultrasonographic marker for the first trimester of gestation, in the detection of adverse fetal outcome, especially serious malformations. The ductus venosus was able to diminish the false-positive result in comparison to the isolated use of the nuchal translucency thickness, improving considerably the positive predictive value of the test.
Summary
Revista Brasileira de Ginecologia e Obstetrícia. 1999;21(3):147-152
DOI 10.1590/S0100-72031999000300005
Purpose: to determine the possible occurrence of hemodynamic changes in the middle cerebral artery of the fetus (MCA) using color doppler after vibro-acoustic stimulation. Methods: thirty fetuses from pregnant women considered to be clinically normal, with a gestational age of 28 weeks or more were submitted to vibro-acoustic stimulation. We examined the changes in blood flow rate in the middle cerebral artery of the fetus on the basis of resistance index (RI) and fetal heart rate (FHR) by color doppler before and after the sound stimulus. Results: mean FHR before vibro-acoustic stimulation was 142.41 beats per minute (bpm) with a standard deviation of 9.01 and a range of 122 to 162 bpm. After stimulation, mean FHR was 159.44 bpm with a standard deviation of 15.49 and a range of 130 to 187 bpm (p<0.01). Mean RI in the MCA of the fetuses was 75.89% (range: 64 to 91%) before the experiment. After the vibro-acoustic stimulation, mean RI was 66.93% (range: 47 to 83%; p < 0.01). Conclusions: we observed that a sound stimulus provokes the well-known immediate and significant elevation of FHR and a decrease in cerebral vascular resistance when evaluated by the RI of the fetal middle cerebral artery.
Summary
Revista Brasileira de Ginecologia e Obstetrícia. 1999;21(3):147-152
DOI 10.1590/S0100-72031999000300005
Purpose: to determine the possible occurrence of hemodynamic changes in the middle cerebral artery of the fetus (MCA) using color doppler after vibro-acoustic stimulation. Methods: thirty fetuses from pregnant women considered to be clinically normal, with a gestational age of 28 weeks or more were submitted to vibro-acoustic stimulation. We examined the changes in blood flow rate in the middle cerebral artery of the fetus on the basis of resistance index (RI) and fetal heart rate (FHR) by color doppler before and after the sound stimulus. Results: mean FHR before vibro-acoustic stimulation was 142.41 beats per minute (bpm) with a standard deviation of 9.01 and a range of 122 to 162 bpm. After stimulation, mean FHR was 159.44 bpm with a standard deviation of 15.49 and a range of 130 to 187 bpm (p<0.01). Mean RI in the MCA of the fetuses was 75.89% (range: 64 to 91%) before the experiment. After the vibro-acoustic stimulation, mean RI was 66.93% (range: 47 to 83%; p < 0.01). Conclusions: we observed that a sound stimulus provokes the well-known immediate and significant elevation of FHR and a decrease in cerebral vascular resistance when evaluated by the RI of the fetal middle cerebral artery.
Summary
Revista Brasileira de Ginecologia e Obstetrícia. 2006;28(8):453-459
DOI 10.1590/S0100-72032006000800003
PURPOSE: to analyze the fetal heart rate (FHR) and umbilical artery Dopplervelocimetry between 18th and 20th weeks of gestation in pregnant women complicated by pregestational diabetes mellitus. METHODS: twenty-eight pregnancies with pregestational diabetes and 27 normal pregnant women were analyzed prospectively, in a cross-sectional and case-control study. The inclusion criteria were the following: singleton pregnancy between 18 and 29 weeks, no other associated maternal diseases and no fetal abnormality. Ultrasonography was performed and FHR was calculated by the interval between the beginnings of two consecutive cardiac cycles, in the three umbilical artery Doppler sonograms, obtained in the umbilical cord near to the placental insertion, using color Doppler. Five consecutive FHR cycles from each sonogram were measured, to analyze mean FHR and its variation. The following Doppler indices were studied: systolic/diastolic ratio, pulsatility index (PI) and resistance index (RI). Student's t test and Mann-Whitney Utest were applied to comparative study. p values were considered significant when p<0.05. Results: no significant difference was observed in mean FHR between the studied groups (diabetic group: 149.2 bpm, control group: 147.2 bpm; p = 0.12). FHR variation revealed similar results between the groups (diabetic group: 5.3 bpm; control group: 5.3 bpm; p=0.50). No significant difference was found in the Doppler indices S/D (p=0.79), PI (p=0.25) and RI (p=0.71) between the groups. CONCLUSIONS: the absence of differences in FHR characteristics between the 18th and 20th gestational weeks indicates similar neurological maturation of FHR regulatory systems in this period, between fetuses of diabetic mothers and controls. Abnormalities in the uteroplacental resistance were not identified in the studied period, in pregnancies complicated by pregestational diabetes.
Summary
Revista Brasileira de Ginecologia e Obstetrícia. 2006;28(8):453-459
DOI 10.1590/S0100-72032006000800003
PURPOSE: to analyze the fetal heart rate (FHR) and umbilical artery Dopplervelocimetry between 18th and 20th weeks of gestation in pregnant women complicated by pregestational diabetes mellitus. METHODS: twenty-eight pregnancies with pregestational diabetes and 27 normal pregnant women were analyzed prospectively, in a cross-sectional and case-control study. The inclusion criteria were the following: singleton pregnancy between 18 and 29 weeks, no other associated maternal diseases and no fetal abnormality. Ultrasonography was performed and FHR was calculated by the interval between the beginnings of two consecutive cardiac cycles, in the three umbilical artery Doppler sonograms, obtained in the umbilical cord near to the placental insertion, using color Doppler. Five consecutive FHR cycles from each sonogram were measured, to analyze mean FHR and its variation. The following Doppler indices were studied: systolic/diastolic ratio, pulsatility index (PI) and resistance index (RI). Student's t test and Mann-Whitney Utest were applied to comparative study. p values were considered significant when p<0.05. Results: no significant difference was observed in mean FHR between the studied groups (diabetic group: 149.2 bpm, control group: 147.2 bpm; p = 0.12). FHR variation revealed similar results between the groups (diabetic group: 5.3 bpm; control group: 5.3 bpm; p=0.50). No significant difference was found in the Doppler indices S/D (p=0.79), PI (p=0.25) and RI (p=0.71) between the groups. CONCLUSIONS: the absence of differences in FHR characteristics between the 18th and 20th gestational weeks indicates similar neurological maturation of FHR regulatory systems in this period, between fetuses of diabetic mothers and controls. Abnormalities in the uteroplacental resistance were not identified in the studied period, in pregnancies complicated by pregestational diabetes.
Summary
Revista Brasileira de Ginecologia e Obstetrícia. 2002;24(7):447-452
DOI 10.1590/S0100-72032002000700004
Purpose: to compare the size of locally advanced breast tumors through clinical examination, mammography, and ultrasound, and describe the parameters of color Doppler ultrasound evaluated before and after primary chemotherapy. Methods: it was a prospective and descriptive clinical study. Eighteen women with the diagnosis of breast carcinoma, with clinical primary tumors of 50 mm or larger, were submitted to palpation, mammography, ultrasound and color Doppler ultrasound at the moment of diagnosis and after 3 cycles of chemotherapy. The response was considered present when there was a clinical decrease of 50% or more and an ultrasonographic decrease of 25% or more, and absent when there was a clinical decrease less than 50% and ultrasonographic decrease less than 25%. A descriptive statistical analysis and Wilcoxon test were used. Results: regarding the size of the tumors, the method whose results were closer to pathological examination was the clinical examination after chemotherapy, when compared with sizes on ultrasound and mammography. The mammography helped to evaluate 44% of the cases before chemotherapy (8/18). In the cases where the response was absent, the Doppler showed a significant increase of the flow and a decrease of resistance and pulsatility index. In the cases where the response was present (9 cases), the Doppler did not show any significant change regarding the studied parameters. Conclusion: clinical examination was the most efficient method to evaluate the decrease of the volume of tumors submitted to neoadjuvant chemotherapy when compared with ultrasound and mammographic examinations. Doppler showed increase of the flow in the cases of absent response.
Summary
Revista Brasileira de Ginecologia e Obstetrícia. 2002;24(7):447-452
DOI 10.1590/S0100-72032002000700004
Purpose: to compare the size of locally advanced breast tumors through clinical examination, mammography, and ultrasound, and describe the parameters of color Doppler ultrasound evaluated before and after primary chemotherapy. Methods: it was a prospective and descriptive clinical study. Eighteen women with the diagnosis of breast carcinoma, with clinical primary tumors of 50 mm or larger, were submitted to palpation, mammography, ultrasound and color Doppler ultrasound at the moment of diagnosis and after 3 cycles of chemotherapy. The response was considered present when there was a clinical decrease of 50% or more and an ultrasonographic decrease of 25% or more, and absent when there was a clinical decrease less than 50% and ultrasonographic decrease less than 25%. A descriptive statistical analysis and Wilcoxon test were used. Results: regarding the size of the tumors, the method whose results were closer to pathological examination was the clinical examination after chemotherapy, when compared with sizes on ultrasound and mammography. The mammography helped to evaluate 44% of the cases before chemotherapy (8/18). In the cases where the response was absent, the Doppler showed a significant increase of the flow and a decrease of resistance and pulsatility index. In the cases where the response was present (9 cases), the Doppler did not show any significant change regarding the studied parameters. Conclusion: clinical examination was the most efficient method to evaluate the decrease of the volume of tumors submitted to neoadjuvant chemotherapy when compared with ultrasound and mammographic examinations. Doppler showed increase of the flow in the cases of absent response.