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Stuart Campbell - One of the best experts on this subject based on the ideXlab platform.

  • changes observed in Doppler Studies of the fetal circulation in pregnancies complicated by pre eclampsia or the delivery of a small for gestational age baby i cross sectional analysis
    Ultrasound in Obstetrics & Gynecology, 1995
    Co-Authors: K. Harrington, R. G. Carpenter, M. Nguyen, Stuart Campbell
    Abstract:

    The aim of this study was to compare changes in Doppler Ultrasound Studies of the fetal circulation in normal pregnancies with a group of pregnancies complicated by proteinuric pregnancy-induced hypertension (PPIH), delivery of a small-for-gestational-age (SGA) baby, or both. A total of 167 uncomplicated pregnancies with a term delivery of an appropriately grown baby (AGA) were used to define the normal range. Altogether, 123 high-risk pregnancies with a known outcome constituted the study group. A color duplex Ultrasound machine was used to perform biometry and fetal Doppler Studies. Measurements obtained from the fetal circulation included the umbilical artery (UA) pulsatility index (PI), the middle cerebral artery (MCA) PI and time-averaged velocity (TAV), the thoracic aorta (AO) PI and TAV. In addition, the ratio between the MCA PI and UA PI, the MCA PI and the AO PI, and the product of the MCA PI and AO TAV were used in the analysis. A total of 105 pregnancies had a complicated outcome. They were divided into three categories: PPIH only (pregnancies complicated by PPIH with the delivery of an AGA fetus, n = 17), SGA only (delivery of an SGA baby, with no evidence of PPIH, n = 55), and PPIH + SGA (pregnancies complicated by pre-eclampsia and delivery of an SGA baby, n = 37). The PPIH + SGA group represented true clinical intrauterine growth retardation. Cross-sectional reference ranges were created using the observations from the normal group. z-scores (standard deviation from the mean of the normal range) of the last observations made before delivery were calculated for each of the vessel velocimetry measurements and ratios. The statistical significance of z-score values was calculated using analysis of variance. The MCA and UA PI values showed the greatest deviation for any single-vessel parameter. The ratios of fetal Doppler indices (MCA/UA PI ratio, MCA/AO PI ratio and the MCA PI/AO TAV index) demonstrated greater deviation from normal than any individual vessel. The UA PI z-score for PPIH+SGA delivering or = 34 weeks (1.20, p < 0.05). Fetal Doppler indices, in particular ratios that include measurements obtained from the cerebral circulation, help in the recognition of the small fetus that is growth-retarded. At term, evidence of fetal hemodynamic redistribution may exist in the presence of a normal umbilical artery PI. Fetal Doppler indices provide information that is not readily obtained from more conventional tests of fetal well-being.(ABSTRACT TRUNCATED AT 400 WORDS)

  • changes observed in Doppler Studies of the fetal circulation in pregnancies complicated by pre eclampsia or the delivery of a small for gestational age baby i cross sectional analysis
    Ultrasound in Obstetrics & Gynecology, 1995
    Co-Authors: K. Harrington, R. G. Carpenter, M. Nguyen, Stuart Campbell
    Abstract:

    The aim of this study was to compare changes in Doppler Ultrasound Studies of the fetal circulation in normal pregnancies with a group of pregnancies complicated by proteinuric pregnancy-induced hypertension (PPIH), delivery of a small-for-gestational-age (SGA) baby, or both. A total of 167 uncomplicated pregnancies with a term delivery of an appropriately grown baby (AGA) were used to define the normal range. Altogether, 123 high-risk pregnancies with a known outcome constituted the study group. A color duplex Ultrasound machine was used to perform biometry and fetal Doppler Studies. Measurements obtained from the fetal circulation included the umbilical artery (UA) pulsatility index (PI), the middle cerebral artery (MCA) PI and time-averaged velocity (TAV), the thoracic aorta (AO) PI and TAV In addition, the ratio between the MCA PI and UA PI, the MCA PI and the A0 PI, and the product of the MCA PI and A0 TAV were used in the analysis. A total of 105 pregnancies had a complicated outcome. They were divided into three categories: PPIH only (pregnancies complicated by PPIH with the delivery of an AGA fetus, n = 17), SGA only (delivery of an SGA baby, with no evidence of PPIH, n = 55), and PPIH + SGA (pregnancies complicated by pre-eclampsia and delivery of an SGA baby, n = 37). The PPIH + SGA group represented true clinical intrauterine growth retardation. Cross-sectional reference ranges were created using the observations from the normal group. z-scores (standard deviation from the mean of the normal range) of the last observations made before delivery were calculated for each of the vessel velocimetry measurements and ratios. The statistical significance of z-score values was calculated using analysis of variance. The MCA and UA PI values showed the greatest deviation for any single-vessel parameter. The ratios of fetal Doppler indices (MCA/UA PI ratio, MCA/AO PI ratio and the MCA PI/A0 TAV index) demonstrated greater deviation from normal than any individual vessel. The UA PI z-score for PPIH + SGA delivering < 34 weeks gestation (2.92) was significantly greater than the z-score for PPIH + SGA delivering ≥ 34 weeks (1.20, p < 0.05). Fetal Doppler indices, in particular ratios that include measurements obtained from the cerebral circulation, help in the recognition of the small fetus that is growth-retarded. At term, evidence of fetal hemodynamic redistribution may exist in the presence of a normal umbilical artery PI. Fetal Doppler indices provide information that is not readily obtained from more conventional tests of fetal well-being. It therefore has an important role to play in the management of the growth-retarded fetus. Copyright © 1995 International Society of Ultrasound in Obstetrics and Gynecology

J Li - One of the best experts on this subject based on the ideXlab platform.

  • evaluation of the facial artery and vein using color Doppler imaging
    Chinese journal of plastic surgery, 2002
    Co-Authors: Z Zhao, S Li, Y Li, M Yang, W Huang, H Zhai, J Li, X Fu
    Abstract:

    Objective\ The purpose of this study was to provide the guidelines with respect to the location of the facial vessels, observe the potential reversed flow of the facial artery, and reemphasize the value of color Doppler Ultrasound Studies in flap planning. Methods\ A study was carried out to investigate the location and dynamics of the facial artery and vein using color Doppler ultrasonography in 12 adults. Results\ The facial artery and the vein were located together at the lower border of the mandible. Around the oral commissure and under the nasal ala, they run apart from each other at variable distances. The reverse flow was observed in the 12 patients after the blood flow of the facial artery was blocked by applying pressure manually at the lower border of the mandible. Conclusions\ The divergence of the facial vein from the artery is important information in planning of axial pattern flaps. Observation of the reversed flow confirms the possibility of safe elevation of a retrograde flow arterialized flap based on the distal portion of the facial artery.\;

  • color Doppler flow imaging of the facial artery and vein
    Plastic and Reconstructive Surgery, 2000
    Co-Authors: Z Zhao, S Li, Y Li, M Yang, W Huang, H Zhai, J Li, Jun Xu, Lanhua Mu
    Abstract:

    The purpose of this study was to provide some guidelines with respect to the location of the facial vessels, display the potential inverted blood flow of the facial artery, and reemphasize the value of color Doppler Ultrasound Studies in flap planning. An anatomic study of the facial artery and vein was done using color Doppler ultrasonography in 12 adults. The artery and the vein were located together at the lower border of the mandible. Around the oral commissure and under the nasal ala, they were located apart from each other with variable distances. This divergence of the facial vein from the artery is important information in the planning of axial pattern flaps. Furthermore, the reverse flow was observed in 12 patients after the blood flow of the facial artery was stopped by applying pressure manually at the lower border of the mandible. Observation of the reversed flow confirms the possibility of safe elevation of a retrograde flow-arterialized flap based on the distal portion of the facial artery.

K. Harrington - One of the best experts on this subject based on the ideXlab platform.

  • transvaginal Doppler Ultrasound of the uteroplacental circulation in the early prediction of pre eclampsia and intrauterine growth retardation
    British Journal of Obstetrics and Gynaecology, 1997
    Co-Authors: K. Harrington, R. G. Carpenter, C Goldfrad, S Campbell
    Abstract:

    Objective To evaluate the predictive value of transvaginal Doppler Ultrasound Studies of the uterine and umbilical arteries in early pregnancy, in identifying pregnant women at risk of subsequently developing pre-eclampsia, or the delivery of a small for gestational age infant. Design A multivariate logistic regression of Z scores of Doppler indices obtained from the uterine and umbilical arteries of 652 women with singleton pregnancies at 12 to 16 weeks of gestation. Measurements included the presence or absence of a notch, bilateral (right and left waveform) notching, vessel diameter, the resistance index, the pulsatility index, time averaged mean velocity (cm/s), maximum systolic velocity (cm/s), and volume flow (mL/min). Stepwise logistic regression and multivariate analysis of all the parameters measured was used to construct several scoring systems. Main outcome measures Pre-eclampsia, birthweight, preterm delivery. Results In women that developed complications, there was a trend towards increased resistance and reduced velocity and volume flow. If bilateral notches were present there was an increased risk of pre-eclampsia (odds ratio [OR] 21.99, 95% CI 6.55–73.79), premature delivery (OR 2.38, 95% CI 1.19–4.75), and the delivery of a small for gestational age baby (OR 8.63, 95% CI 3.95–18.84). Using multivariate analysis, a seven parameter model was selected (after removal of vessel diameter, uterine and umbilical resistance index). This model produces a scoring system with a sensitivity of 92.9% and a specificity of 85.1% for the prediction of pre-eclampsia. A three parameter model (bilateral notches, uterine resistance index, umbilical pulsatility index) provides similar sensitivities, but lower specificities, when compared with the seven parameter model. Conclusion These data indicate that there are differences in uterine and umbilical artery Doppler blood flow indices at 12 to 16 weeks, in pregnancies with a normal or complicated outcome. Scoring systems derived from multivariate analysis of Doppler indices demonstrate the potential of being able to identify, in early pregnancy, a group of women at increased risk of the subsequent development of pre-eclampsia, premature delivery, or the birth of a small for gestational age baby.

  • changes observed in Doppler Studies of the fetal circulation in pregnancies complicated by pre eclampsia or the delivery of a small for gestational age baby i cross sectional analysis
    Ultrasound in Obstetrics & Gynecology, 1995
    Co-Authors: K. Harrington, R. G. Carpenter, M. Nguyen, Stuart Campbell
    Abstract:

    The aim of this study was to compare changes in Doppler Ultrasound Studies of the fetal circulation in normal pregnancies with a group of pregnancies complicated by proteinuric pregnancy-induced hypertension (PPIH), delivery of a small-for-gestational-age (SGA) baby, or both. A total of 167 uncomplicated pregnancies with a term delivery of an appropriately grown baby (AGA) were used to define the normal range. Altogether, 123 high-risk pregnancies with a known outcome constituted the study group. A color duplex Ultrasound machine was used to perform biometry and fetal Doppler Studies. Measurements obtained from the fetal circulation included the umbilical artery (UA) pulsatility index (PI), the middle cerebral artery (MCA) PI and time-averaged velocity (TAV), the thoracic aorta (AO) PI and TAV. In addition, the ratio between the MCA PI and UA PI, the MCA PI and the AO PI, and the product of the MCA PI and AO TAV were used in the analysis. A total of 105 pregnancies had a complicated outcome. They were divided into three categories: PPIH only (pregnancies complicated by PPIH with the delivery of an AGA fetus, n = 17), SGA only (delivery of an SGA baby, with no evidence of PPIH, n = 55), and PPIH + SGA (pregnancies complicated by pre-eclampsia and delivery of an SGA baby, n = 37). The PPIH + SGA group represented true clinical intrauterine growth retardation. Cross-sectional reference ranges were created using the observations from the normal group. z-scores (standard deviation from the mean of the normal range) of the last observations made before delivery were calculated for each of the vessel velocimetry measurements and ratios. The statistical significance of z-score values was calculated using analysis of variance. The MCA and UA PI values showed the greatest deviation for any single-vessel parameter. The ratios of fetal Doppler indices (MCA/UA PI ratio, MCA/AO PI ratio and the MCA PI/AO TAV index) demonstrated greater deviation from normal than any individual vessel. The UA PI z-score for PPIH+SGA delivering or = 34 weeks (1.20, p < 0.05). Fetal Doppler indices, in particular ratios that include measurements obtained from the cerebral circulation, help in the recognition of the small fetus that is growth-retarded. At term, evidence of fetal hemodynamic redistribution may exist in the presence of a normal umbilical artery PI. Fetal Doppler indices provide information that is not readily obtained from more conventional tests of fetal well-being.(ABSTRACT TRUNCATED AT 400 WORDS)

  • changes observed in Doppler Studies of the fetal circulation in pregnancies complicated by pre eclampsia or the delivery of a small for gestational age baby i cross sectional analysis
    Ultrasound in Obstetrics & Gynecology, 1995
    Co-Authors: K. Harrington, R. G. Carpenter, M. Nguyen, Stuart Campbell
    Abstract:

    The aim of this study was to compare changes in Doppler Ultrasound Studies of the fetal circulation in normal pregnancies with a group of pregnancies complicated by proteinuric pregnancy-induced hypertension (PPIH), delivery of a small-for-gestational-age (SGA) baby, or both. A total of 167 uncomplicated pregnancies with a term delivery of an appropriately grown baby (AGA) were used to define the normal range. Altogether, 123 high-risk pregnancies with a known outcome constituted the study group. A color duplex Ultrasound machine was used to perform biometry and fetal Doppler Studies. Measurements obtained from the fetal circulation included the umbilical artery (UA) pulsatility index (PI), the middle cerebral artery (MCA) PI and time-averaged velocity (TAV), the thoracic aorta (AO) PI and TAV In addition, the ratio between the MCA PI and UA PI, the MCA PI and the A0 PI, and the product of the MCA PI and A0 TAV were used in the analysis. A total of 105 pregnancies had a complicated outcome. They were divided into three categories: PPIH only (pregnancies complicated by PPIH with the delivery of an AGA fetus, n = 17), SGA only (delivery of an SGA baby, with no evidence of PPIH, n = 55), and PPIH + SGA (pregnancies complicated by pre-eclampsia and delivery of an SGA baby, n = 37). The PPIH + SGA group represented true clinical intrauterine growth retardation. Cross-sectional reference ranges were created using the observations from the normal group. z-scores (standard deviation from the mean of the normal range) of the last observations made before delivery were calculated for each of the vessel velocimetry measurements and ratios. The statistical significance of z-score values was calculated using analysis of variance. The MCA and UA PI values showed the greatest deviation for any single-vessel parameter. The ratios of fetal Doppler indices (MCA/UA PI ratio, MCA/AO PI ratio and the MCA PI/A0 TAV index) demonstrated greater deviation from normal than any individual vessel. The UA PI z-score for PPIH + SGA delivering < 34 weeks gestation (2.92) was significantly greater than the z-score for PPIH + SGA delivering ≥ 34 weeks (1.20, p < 0.05). Fetal Doppler indices, in particular ratios that include measurements obtained from the cerebral circulation, help in the recognition of the small fetus that is growth-retarded. At term, evidence of fetal hemodynamic redistribution may exist in the presence of a normal umbilical artery PI. Fetal Doppler indices provide information that is not readily obtained from more conventional tests of fetal well-being. It therefore has an important role to play in the management of the growth-retarded fetus. Copyright © 1995 International Society of Ultrasound in Obstetrics and Gynecology

R. G. Carpenter - One of the best experts on this subject based on the ideXlab platform.

  • transvaginal Doppler Ultrasound of the uteroplacental circulation in the early prediction of pre eclampsia and intrauterine growth retardation
    British Journal of Obstetrics and Gynaecology, 1997
    Co-Authors: K. Harrington, R. G. Carpenter, C Goldfrad, S Campbell
    Abstract:

    Objective To evaluate the predictive value of transvaginal Doppler Ultrasound Studies of the uterine and umbilical arteries in early pregnancy, in identifying pregnant women at risk of subsequently developing pre-eclampsia, or the delivery of a small for gestational age infant. Design A multivariate logistic regression of Z scores of Doppler indices obtained from the uterine and umbilical arteries of 652 women with singleton pregnancies at 12 to 16 weeks of gestation. Measurements included the presence or absence of a notch, bilateral (right and left waveform) notching, vessel diameter, the resistance index, the pulsatility index, time averaged mean velocity (cm/s), maximum systolic velocity (cm/s), and volume flow (mL/min). Stepwise logistic regression and multivariate analysis of all the parameters measured was used to construct several scoring systems. Main outcome measures Pre-eclampsia, birthweight, preterm delivery. Results In women that developed complications, there was a trend towards increased resistance and reduced velocity and volume flow. If bilateral notches were present there was an increased risk of pre-eclampsia (odds ratio [OR] 21.99, 95% CI 6.55–73.79), premature delivery (OR 2.38, 95% CI 1.19–4.75), and the delivery of a small for gestational age baby (OR 8.63, 95% CI 3.95–18.84). Using multivariate analysis, a seven parameter model was selected (after removal of vessel diameter, uterine and umbilical resistance index). This model produces a scoring system with a sensitivity of 92.9% and a specificity of 85.1% for the prediction of pre-eclampsia. A three parameter model (bilateral notches, uterine resistance index, umbilical pulsatility index) provides similar sensitivities, but lower specificities, when compared with the seven parameter model. Conclusion These data indicate that there are differences in uterine and umbilical artery Doppler blood flow indices at 12 to 16 weeks, in pregnancies with a normal or complicated outcome. Scoring systems derived from multivariate analysis of Doppler indices demonstrate the potential of being able to identify, in early pregnancy, a group of women at increased risk of the subsequent development of pre-eclampsia, premature delivery, or the birth of a small for gestational age baby.

  • changes observed in Doppler Studies of the fetal circulation in pregnancies complicated by pre eclampsia or the delivery of a small for gestational age baby i cross sectional analysis
    Ultrasound in Obstetrics & Gynecology, 1995
    Co-Authors: K. Harrington, R. G. Carpenter, M. Nguyen, Stuart Campbell
    Abstract:

    The aim of this study was to compare changes in Doppler Ultrasound Studies of the fetal circulation in normal pregnancies with a group of pregnancies complicated by proteinuric pregnancy-induced hypertension (PPIH), delivery of a small-for-gestational-age (SGA) baby, or both. A total of 167 uncomplicated pregnancies with a term delivery of an appropriately grown baby (AGA) were used to define the normal range. Altogether, 123 high-risk pregnancies with a known outcome constituted the study group. A color duplex Ultrasound machine was used to perform biometry and fetal Doppler Studies. Measurements obtained from the fetal circulation included the umbilical artery (UA) pulsatility index (PI), the middle cerebral artery (MCA) PI and time-averaged velocity (TAV), the thoracic aorta (AO) PI and TAV. In addition, the ratio between the MCA PI and UA PI, the MCA PI and the AO PI, and the product of the MCA PI and AO TAV were used in the analysis. A total of 105 pregnancies had a complicated outcome. They were divided into three categories: PPIH only (pregnancies complicated by PPIH with the delivery of an AGA fetus, n = 17), SGA only (delivery of an SGA baby, with no evidence of PPIH, n = 55), and PPIH + SGA (pregnancies complicated by pre-eclampsia and delivery of an SGA baby, n = 37). The PPIH + SGA group represented true clinical intrauterine growth retardation. Cross-sectional reference ranges were created using the observations from the normal group. z-scores (standard deviation from the mean of the normal range) of the last observations made before delivery were calculated for each of the vessel velocimetry measurements and ratios. The statistical significance of z-score values was calculated using analysis of variance. The MCA and UA PI values showed the greatest deviation for any single-vessel parameter. The ratios of fetal Doppler indices (MCA/UA PI ratio, MCA/AO PI ratio and the MCA PI/AO TAV index) demonstrated greater deviation from normal than any individual vessel. The UA PI z-score for PPIH+SGA delivering or = 34 weeks (1.20, p < 0.05). Fetal Doppler indices, in particular ratios that include measurements obtained from the cerebral circulation, help in the recognition of the small fetus that is growth-retarded. At term, evidence of fetal hemodynamic redistribution may exist in the presence of a normal umbilical artery PI. Fetal Doppler indices provide information that is not readily obtained from more conventional tests of fetal well-being.(ABSTRACT TRUNCATED AT 400 WORDS)

  • changes observed in Doppler Studies of the fetal circulation in pregnancies complicated by pre eclampsia or the delivery of a small for gestational age baby i cross sectional analysis
    Ultrasound in Obstetrics & Gynecology, 1995
    Co-Authors: K. Harrington, R. G. Carpenter, M. Nguyen, Stuart Campbell
    Abstract:

    The aim of this study was to compare changes in Doppler Ultrasound Studies of the fetal circulation in normal pregnancies with a group of pregnancies complicated by proteinuric pregnancy-induced hypertension (PPIH), delivery of a small-for-gestational-age (SGA) baby, or both. A total of 167 uncomplicated pregnancies with a term delivery of an appropriately grown baby (AGA) were used to define the normal range. Altogether, 123 high-risk pregnancies with a known outcome constituted the study group. A color duplex Ultrasound machine was used to perform biometry and fetal Doppler Studies. Measurements obtained from the fetal circulation included the umbilical artery (UA) pulsatility index (PI), the middle cerebral artery (MCA) PI and time-averaged velocity (TAV), the thoracic aorta (AO) PI and TAV In addition, the ratio between the MCA PI and UA PI, the MCA PI and the A0 PI, and the product of the MCA PI and A0 TAV were used in the analysis. A total of 105 pregnancies had a complicated outcome. They were divided into three categories: PPIH only (pregnancies complicated by PPIH with the delivery of an AGA fetus, n = 17), SGA only (delivery of an SGA baby, with no evidence of PPIH, n = 55), and PPIH + SGA (pregnancies complicated by pre-eclampsia and delivery of an SGA baby, n = 37). The PPIH + SGA group represented true clinical intrauterine growth retardation. Cross-sectional reference ranges were created using the observations from the normal group. z-scores (standard deviation from the mean of the normal range) of the last observations made before delivery were calculated for each of the vessel velocimetry measurements and ratios. The statistical significance of z-score values was calculated using analysis of variance. The MCA and UA PI values showed the greatest deviation for any single-vessel parameter. The ratios of fetal Doppler indices (MCA/UA PI ratio, MCA/AO PI ratio and the MCA PI/A0 TAV index) demonstrated greater deviation from normal than any individual vessel. The UA PI z-score for PPIH + SGA delivering < 34 weeks gestation (2.92) was significantly greater than the z-score for PPIH + SGA delivering ≥ 34 weeks (1.20, p < 0.05). Fetal Doppler indices, in particular ratios that include measurements obtained from the cerebral circulation, help in the recognition of the small fetus that is growth-retarded. At term, evidence of fetal hemodynamic redistribution may exist in the presence of a normal umbilical artery PI. Fetal Doppler indices provide information that is not readily obtained from more conventional tests of fetal well-being. It therefore has an important role to play in the management of the growth-retarded fetus. Copyright © 1995 International Society of Ultrasound in Obstetrics and Gynecology

M. Nguyen - One of the best experts on this subject based on the ideXlab platform.

  • changes observed in Doppler Studies of the fetal circulation in pregnancies complicated by pre eclampsia or the delivery of a small for gestational age baby i cross sectional analysis
    Ultrasound in Obstetrics & Gynecology, 1995
    Co-Authors: K. Harrington, R. G. Carpenter, M. Nguyen, Stuart Campbell
    Abstract:

    The aim of this study was to compare changes in Doppler Ultrasound Studies of the fetal circulation in normal pregnancies with a group of pregnancies complicated by proteinuric pregnancy-induced hypertension (PPIH), delivery of a small-for-gestational-age (SGA) baby, or both. A total of 167 uncomplicated pregnancies with a term delivery of an appropriately grown baby (AGA) were used to define the normal range. Altogether, 123 high-risk pregnancies with a known outcome constituted the study group. A color duplex Ultrasound machine was used to perform biometry and fetal Doppler Studies. Measurements obtained from the fetal circulation included the umbilical artery (UA) pulsatility index (PI), the middle cerebral artery (MCA) PI and time-averaged velocity (TAV), the thoracic aorta (AO) PI and TAV. In addition, the ratio between the MCA PI and UA PI, the MCA PI and the AO PI, and the product of the MCA PI and AO TAV were used in the analysis. A total of 105 pregnancies had a complicated outcome. They were divided into three categories: PPIH only (pregnancies complicated by PPIH with the delivery of an AGA fetus, n = 17), SGA only (delivery of an SGA baby, with no evidence of PPIH, n = 55), and PPIH + SGA (pregnancies complicated by pre-eclampsia and delivery of an SGA baby, n = 37). The PPIH + SGA group represented true clinical intrauterine growth retardation. Cross-sectional reference ranges were created using the observations from the normal group. z-scores (standard deviation from the mean of the normal range) of the last observations made before delivery were calculated for each of the vessel velocimetry measurements and ratios. The statistical significance of z-score values was calculated using analysis of variance. The MCA and UA PI values showed the greatest deviation for any single-vessel parameter. The ratios of fetal Doppler indices (MCA/UA PI ratio, MCA/AO PI ratio and the MCA PI/AO TAV index) demonstrated greater deviation from normal than any individual vessel. The UA PI z-score for PPIH+SGA delivering or = 34 weeks (1.20, p < 0.05). Fetal Doppler indices, in particular ratios that include measurements obtained from the cerebral circulation, help in the recognition of the small fetus that is growth-retarded. At term, evidence of fetal hemodynamic redistribution may exist in the presence of a normal umbilical artery PI. Fetal Doppler indices provide information that is not readily obtained from more conventional tests of fetal well-being.(ABSTRACT TRUNCATED AT 400 WORDS)

  • changes observed in Doppler Studies of the fetal circulation in pregnancies complicated by pre eclampsia or the delivery of a small for gestational age baby i cross sectional analysis
    Ultrasound in Obstetrics & Gynecology, 1995
    Co-Authors: K. Harrington, R. G. Carpenter, M. Nguyen, Stuart Campbell
    Abstract:

    The aim of this study was to compare changes in Doppler Ultrasound Studies of the fetal circulation in normal pregnancies with a group of pregnancies complicated by proteinuric pregnancy-induced hypertension (PPIH), delivery of a small-for-gestational-age (SGA) baby, or both. A total of 167 uncomplicated pregnancies with a term delivery of an appropriately grown baby (AGA) were used to define the normal range. Altogether, 123 high-risk pregnancies with a known outcome constituted the study group. A color duplex Ultrasound machine was used to perform biometry and fetal Doppler Studies. Measurements obtained from the fetal circulation included the umbilical artery (UA) pulsatility index (PI), the middle cerebral artery (MCA) PI and time-averaged velocity (TAV), the thoracic aorta (AO) PI and TAV In addition, the ratio between the MCA PI and UA PI, the MCA PI and the A0 PI, and the product of the MCA PI and A0 TAV were used in the analysis. A total of 105 pregnancies had a complicated outcome. They were divided into three categories: PPIH only (pregnancies complicated by PPIH with the delivery of an AGA fetus, n = 17), SGA only (delivery of an SGA baby, with no evidence of PPIH, n = 55), and PPIH + SGA (pregnancies complicated by pre-eclampsia and delivery of an SGA baby, n = 37). The PPIH + SGA group represented true clinical intrauterine growth retardation. Cross-sectional reference ranges were created using the observations from the normal group. z-scores (standard deviation from the mean of the normal range) of the last observations made before delivery were calculated for each of the vessel velocimetry measurements and ratios. The statistical significance of z-score values was calculated using analysis of variance. The MCA and UA PI values showed the greatest deviation for any single-vessel parameter. The ratios of fetal Doppler indices (MCA/UA PI ratio, MCA/AO PI ratio and the MCA PI/A0 TAV index) demonstrated greater deviation from normal than any individual vessel. The UA PI z-score for PPIH + SGA delivering < 34 weeks gestation (2.92) was significantly greater than the z-score for PPIH + SGA delivering ≥ 34 weeks (1.20, p < 0.05). Fetal Doppler indices, in particular ratios that include measurements obtained from the cerebral circulation, help in the recognition of the small fetus that is growth-retarded. At term, evidence of fetal hemodynamic redistribution may exist in the presence of a normal umbilical artery PI. Fetal Doppler indices provide information that is not readily obtained from more conventional tests of fetal well-being. It therefore has an important role to play in the management of the growth-retarded fetus. Copyright © 1995 International Society of Ultrasound in Obstetrics and Gynecology