T. Iura

Analysis of Renal Artery Hemodynamics in Normal Fetuses Using the Color Doppler Method

Objective: From analysis of fetal renal artery hemodynamics, we attempted to reveal renal glomerular and tubular function in normal fetuses during pregnancy. Design: The study included 36 cases of normal fetuses from the 20th to the 40th week of gestation; Vmax (the systolic peak velocity of main renal artery), Vmean (time averages of trace of peak velocity) blood flow were initially measured between 20 and 24 weeks of gestation and every 4 weeks thereafter. The measurement was performed a total of five times in a longitudinal study. In addition, the blood flow waveform was concurrently examined. Results: The Vmax was 22.02 ± 0.50 cm/s at 20–24 weeks of gestation. This standard value (100%) was found to increase for each group as follows: 125.2, 149.1, 156.1, and 181.5%. Furthermore, using 20–24weeks of gestation as the standard, the Vmean increased after the 37th week of gestation: 186.7%, respectively. At 20–24 weeks of gestation, the blood flow wave forms consisted of 43.2% type I (only systolic waveforms), and 56.8% type II (both systolic and diastolic waveforms). Type III waveforms (waveforms that extended beyond the diastolic to the next systolic component) were not recognized. In the 33- to 36-week group, 82.6% of the waveforms were type II, and in the 37- to 40-week group, 76.2% of the waveforms were type III. Conclusions: The Vmax and Vmean of the renal artery in normal fetuses exhibit a similar rate increase when 20–24 weeks of gestation is compared to 37–40 weeks of gestation. The blood flow waveforms changed as pregnancy progresses; thus, it was inferred that this finding was related to the development of the renal glomerular and renal tubular function.

Hemodynamic analysis of cephalothoracopagus by the color doppler method : A comparison to normal fetuses via a longitudinal study

In a case of cephalothoracopagus, the umbilical artery (UA) was observed with color Doppler method, and the findings were compared with the hemodynamics of 46 normal fetuses. The patient was a 25-year-old primigravida who had appeared for routine prenatal visits since her 6th week of pregnancy. At a later time, the patient was examined after an interval of 4 weeks. Although an ultrasonography was also conducted, unfortunately, any findings of cephalothoracopagus were not detected. In the 25th week of gestation, we hospitalized her for marked polyhydramnios (amniotic fluid index: 280 mm), at which time an ultrasound examination revealed cephalothoracopagus. In the UA, the Vmax was 30.3 cm/s (normal fetus at 25–28 weeks: 33.5 ± 3.9 cm/s). The UA hemodynamics fell below the normal range. At 26 weeks, the UA Vmax was 56.5 cm/sec, a level which significantly exceeded the normal range. The patient underwent a cesarean section at 27 weeks of gestation; the indication was fetal distress. This is caused by the condition in which the fetal heart beats decreases to 90 beats per minute 3 times during a 10-min period as measured on the cardiotocograms. She delivered a 1,392-gram female with an Apgar score of 2 points (respiratory 1 point and heart rate 1 point). The infant was a cephalothoracopagus, with one head, two hearts, four upper limbs, and four lower limbs. The neonate died from circulatory failure 56 min after birth.

Hemodynamics of the renal artery and descending aorta in fetuses with renal disease using color Doppler ultrasound--longitudinal comparison to normal fetuses.

Abstract Objective: To examine the hemodynamic values of the renal artery (RA) and descending aorta (DA) in normal fetuses, and to compare these values to those of fetuses with renal disease, thus evaluating the usefulness of hemodynamic analysis for the diagnosis of fetal renal disease. Materials and methods: We examined 46 normal fetuses and 15 fetuses with renal disease (six cases of polycystic kidney (PCK) and nine cases of hydronephrosis). We measured the maximum systolic velocity (Vmax) of the RA and DA using color Doppler. Measurements were made five times, from the 20th to the 40th week, in both the control and the renal disease group. Results: In the fetuses with PCK (Potters syndrome) that died postpartum from non-functional kidneys, the Vmax of the RA and DA in the 35th week were 13 cm/s and 25.4 cm/s, respectively. In the fetus with PCK (Trisomy 9) that died due to non-functional kidneys in the 34th week, the values were 13.3 cm/s and 29.6 cm/s, respectively. These values were well below those of the normal group: more than 1.5 SD below the mean. In two fetuses from the nine with hydronephrosis that had a unilateral non-functional kidney, the RA did not clearly show identifiable blood flow. Conclusions: The Vmax of the RA and DA in fetuses with renal disease correlates with fetal kidney function, particularly the RA Vmax. Vmax of 1.5 SD below the mean should be the lower normal limit.

Hemodynamic response of ovarian artery after hCG injection

We have analyzed ovarian hemodynamics immediately after human chorionic gonadotropin (hCG) administration in patients treated by clomiphene-hCG and human menopausal gonadotropin-hCG. This study involved 40 infertile women who signed consents to participate in this study. After intramuscular injection of 10000 IU hCG, the change of ovarian arterial blood flow (BF) was evaluated by color Doppler. Pulsatility index, resistance index, maximum velocity (V(max)), mean velocity, minimum velocity, cross-sectional area of ovarian artery (Area) and BF were measured before and 15-180 min after hCG administration. In the 36 subjects in which ovulation was induced successfully, V(max) and BF increased significantly even at 15 min after hCG administration and thereafter. In the 4 non-ovulatory subjects, no significant changes in any of indices at any of measured time points were observed. Comparative study of non-ovulatory and ovulatory subjects suggested that ovulation may be predicted by the ovarian hemodynamic analysis immediately after hCG administration.

Prenatal Diagnosis of the Hemodynamics of Fetal Renal Disease by Color Doppler Ultrasound

Objective: Hemodynamic analysis of the fetal renal artery elucidated the function of the renal glomerulus and renal tubule in normal growth fetus and was weighed against fetal renal disease. Design: The subjects were fetuses from pregnant women who gave informed consent. There were 6 cases of polycystic kidney, 4 cases of hydronephrosis and 33 cases of fetuses presenting with normal growth. A longitudinal study was performed for normal growth fetuses. Using maximum systolic velocity (Vmax), pulsatility index (PI) and resistance index (RI), the blood flow was measured initially at 20–24 weeks of pregnancy and every 4 weeks thereafter. The measurement was performed 5 times in total. Also, for fetal renal disease, the measurement was performed using the same indexes. Results: In 2 cases of polycystic kidney, which led to death due to postpartum afunctional kidney, Vmax indicated the lower level of less than mean –1.5 SD. In 1 case of single hydronephrosis, the single afunctional kidney was observed postpartum due to blood flow disruption. In 7 cases of normal renal function after birth, it indicated the lower level in some gestational ages but was generally in the normal range. Conclusions: Using indexes to evaluate the glomerulus and renal tubule of fetal renal disease, mean –1.5 SD of Vmax can be considered to be the lower limit in the normal range and expected to be an important factor for the final outcome.

P07.07: An attempt to evaluate placental function by using myometrial blood flow analysis

Objective: 1) To study uterine artery (UtA) flow (ml/min) growth rate along gestation in normal human pregnancies; 2) to evaluate longitudinal changes of UtA flow expressed per unit estimated fetal weight (EFW) (ml/min/kg). Methods: A cohort of twelve singleton uneventful human pregnancies, with a normal mean UtA PI, was included in this longitudinal study. UtA was evidenced by power-Doppler mode and sampled 10–15 mm prior to bifurcation. UtA diameter was measured on a perpendicular view after removing power-Doppler. UtA PI and velocity were measured with a Doppler beam angle < 30◦. The average of three consecutive diameters and velocities was considered. UtA flow was estimated by the formula Q = hV · πD2/4; h coefficient (0.5) was obtained by an ad hoc mathematical model. UtA total flow (ml/min) (right plus left UtA flow) was then expressed per EFW (ml/min/kg). Using linear interpolation, including random effects for the intercept and the slope of gestational age for each fetus, a linear mixed effects model was fitted. Results: Forty-seven ultrasound examinations were performed. Ultrasound exams were performed at 14.3,b1.2 weeks and every 4 weeks until delivery. Each case was definitively included in the study after recording normal perinatal and neonatal outcomes. UtA total flow (ml/min) showed a significant correlation to gestational age (133.6 ml/min at 15 weeks; 415.9 ml/min at 35 weeks) (p < 0.001), with a linear increase of 14.1 ml/min per week (right UtA 5.4 vs. left UtA 8.7 ml/min per week, p NS). UtA flow per unit EFW (ml/min/kg) showed a significant reduction from 780.3 ml/min/kg at 15 weeks to 144.1 ml/min/kg at 35 weeks (reduction rate 40.3 ml/min/kg per week). Conclusions: UtA flow (ml/min) significantly increased along gestation in this longitudinal cohort of normal pregnancies. UtA flow per unit EFW (ml/min/kg) significantly decreased longitudinally, since UtA flow (ml/min) growth rate was lower than fetal weight gain rate along gestation.

P02.58: Prenatal diagnosis of the hemodynamics of fetal renal disease by color Doppler ultrasound

OBJECTIVE Hemodynamic analysis of the fetal renal artery elucidated the function of the renal glomerulus and renal tubule in normal growth fetus and was weighed against fetal renal disease. DESIGN The subjects were fetuses from pregnant women who gave informed consent. There were 6 cases of polycystic kidney, 4 cases of hydronephrosis and 33 cases of fetuses presenting with normal growth. A longitudinal study was performed for normal growth fetuses. Using maximum systolic velocity (V(max)), pulsatility index (PI) and resistance index (RI), the blood flow was measured initially at 20-24 weeks of pregnancy and every 4 weeks thereafter. The measurement was performed 5 times in total. Also, for fetal renal disease, the measurement was performed using the same indexes. RESULTS In 2 cases of polycystic kidney, which led to death due to postpartum afunctional kidney, V(max) indicated the lower level of less than mean -1.5 SD. In 1 case of single hydronephrosis, the single afunctional kidney was observed postpartum due to blood flow disruption. In 7 cases of normal renal function after birth, it indicated the lower level in some gestational ages but was generally in the normal range. CONCLUSIONS Using indexes to evaluate the glomerulus and renal tubule of fetal renal disease, mean -1.5 SD of V(max) can be considered to be the lower limit in the normal range and expected to be an important factor for the final outcome.

P07.16: Analysis of renal artery hemodynamics in normal fetuses using the color Doppler method

Conclusions: Abnormal UADV including the degree of abnormality in late second trimester was closely correlated with severe preeclampsia and severity of pre-eclampsia. Also, UADV was more strongly correlated with perinatal outcome than UmDV in severe pre-eclampsia. Thus, UADV including the degree of abnormality in late second trimester could be useful tools in current obstetrics to detect perinatal outcomes in severe preclampsia.

P07.21: Prenatal diagnosis of the fetal renal diseases by the hemodynamic analysis of feral renal artery by color Doppler ultrasound

decrease the concentration of prostaglandins. (PG) Whether PG have similar effect in human is not known. To evaluate the effect of indomethacin on human FBM, we studied 21 pregnant women who presented with preterm labor (gestational age: < 36 weeks). They were divided into a control group (n = 10) and a group treated with indomethacin (n = 11). For both groups, FBM were measured sonographically and recorded on videotape during a 1 hour baseline period. Then, the treated group received indomethacin in a dose of 2–3 mg/kg.. FBM measurements were repeated 24 h later for both groups. To quantify FBM, we reviewed the videotapes and recorded FBM with an event marker on a polygraph. In treated group, there were significant increases in incidence of FBM (x +/− s.e.: 23 +/− 5 vs. 37 +/− 8% of the time, p < 0.05, Wilcoxon Signed Rank Test) and duration of the longest episode of FBM (84 +/− 13 vs. 196 +/− 25 sec, p < 0.05); the increase in average duration of episodes approached significance (21 +/− 3 vs. 37 +/− 8 sec, p = 0.09). The number of episodes of FBM did not change. In the control group there were no significant changes in any of the measured variables. We conclude that indomethacin given to pregnant women increases incidence and duration of FBM, possibly due to a decrease in fetal concentrations of PG.

P07.12: Hemodynamic analysis of the fetal renal artery of oligohydroamnion using color Doppler ultrasound—comparison with normal fetuses by a longitudinal study

a fetal blood sampling was realized with fetal transfusion in case of fetal anemia. Results: 18 fetuses have been evaluated, the first MCA measures were realized at a mean age of 22 weeks’ gestation (16–33 weeks) and the last one for those cases not transfused at 34 weeks (32–36), the number of MCA measures for each fetus was 6.6 (1–13). 2 fetuses were referred in an hydropic state and their first MCA value was > 1.5 MoM, 2 fetuses had MCA value > 1.5 MoM at the first exam, 7 fetuses had < 1.5 MoM at the first exam and developed > 1.5 MoM after a mean delay of 7 weeks (4–13 w) that is after a mean of 2.5 exams (1–6), and 7 fetuses had MCA value < 1.5 MoM during all the pregnancy. 10 fetuses had fetal blood sampling and 9 required in utero transfusion (39 in utero transfusions have been done with a mean of 4.33 for each fetus), 7 did not have any invasive procedures (41%) and one had an amniotic fluid optical density and this fetus was the only one anemic at birth. One fetus with hydrops died in utero at 23 weeks. The sensitivity of MCA Doppler was 90%, the specificity was100%, the PPV was 100% and the NPP was 89%. Conclusion: MCA peak systolic velocity is a highly sensitive noninvasive method for determining the fetuses with moderate to severe anemia. It allowed to reduce in 41% fetal invasive procedures.The fetal invasive procedures are best indicated and the morbidity of such procedure is reduced.