PubMed Health⌕ Search

Biomedical subjects

C Nimrod

Publications and source records attributed to C Nimrod.

At least 19 recordsLinked to original sources
PubMed1995

Doppler sonographic studies on the ophthalmic and central retinal arteries in the gravid woman.

The aim of this study was to establish normative data as gestation advances for pulsed Doppler evaluation of both the ophthalmic artery and the central retinal artery. After measuring intraocular pressure and blood pressure, pulsed Doppler ultrasonographic examination was performed on the ophthalmic and central retinal arteries in both eyes of 125 normal pregnant women. Nomograms, with 95% prediction intervals, have been generated for the Doppler indices, reflecting blood flow in both the ophthalmic and the central retinal arteries. The use of this technique in the management of pregnancy induced hypertension can now be better evaluated.

Blood Pressure↗
PubMed1992

Transverse cerebellar diameter in twin gestations.

OBJECTIVE: The purpose of this study was to evaluate the significance of transverse cerebellar diameter measurements in twin pregnancies. STUDY DESIGN: A prospective, cross-sectional ultrasonographic study was done on 329 normal singleton fetuses and 47 normal twin pairs. Fetal biometric measurements including biparietal diameter, head circumference, abdominal circumference, femur length, and transverse cerebellar diameter were compared between concordant (n = 13) and discordant (n = 11) twins. RESULTS: (1) There was no significant difference in transverse cerebellar diameter measurements between normal singleton and twin gestations. (2) There was no significant difference in transverse cerebellar diameter measurements in each twin pair. (3) Transverse cerebellar diameter was unaffected by the chorionicity or discordancy. (4) Predicted gestational age by transverse cerebellar diameter nomogram for singletons provided satisfactory correlation for twins. CONCLUSION: Transverse cerebellar diameter may be a useful predictor of gestational age and may be independent of discordant growth in twins.

Biometry↗
PubMed1992

Ultrasonographic measurements of fetal ear.

OBJECTIVE: To establish nomograms of fetal ear measurements. Newborns with trisomies have smaller ears than the normal population. This observation led us to believe that ear measurements might be useful in the antenatal prediction of fetuses with abnormal karyotypes. METHODS: Fetal ear length and width were obtained ultrasonographically in 124 normal singleton pregnancies between 18-42 weeks' gestation. Regression analyses were used to create the nomograms. RESULTS: Linear relationships were found between ear length and width and gestational age (r = 0.956 and 0.898, respectively). In addition, there were significant correlations between ear measurements and biparietal diameter, head circumference, abdominal circumference, and femur length. The ear width-length ratio and the biparietal diameter-ear length ratio were independent of gestational age. CONCLUSION: These normative data may be helpful in the antenatal prediction of chromosomal abnormalities.

Down Syndrome↗
PubMed1992

Multiple births: trends and patterns in Canada, 1974-1990.

This paper examines Canadian trends and patterns in multiple births in relation to total confinements, singleton births, maternal age, parity, gestational age and birth weight using vital statistics from 1974 to 1990. Multiple-birth rates in Canada increased from 912.8 to 1,058.9 per 100,000 confinements between 1974 and 1990. The increase is especially noticeable for women over 30. The rate of triplet and higher-order births increased from 8.3 to 21.7 per 100,000 confinements between 1974 and 1990. The proportion of multiple-birth babies that were pre-term (< 37 weeks gestation period) increased from 32.8% in 1974 to 45.8% in 1990. Factors associated with the increase in multiple births may include the use of assisted pregnancy techniques, and the fact that women aged 30 and older, who are at higher risk of a multiple birth, and who postponed their child bearing, have increased their fertility. The sharp increase in multiple-birth rates has implications for maternal and child health and health care costs.

Adolescent↗
PubMed1989

Simultaneous use of Doppler ultrasound and electromagnetic flow probes in fetal flow assessment.

A placental embolization model in the fetal lamb was used to examine the relationship between acute and chronic alternations in placental vascular resistance and changes in flow velocity waveforms as measured by Doppler and electromagnetic flow probes. The peak systolic to end-diastolic (S/D) ratio measured by these techniques was .885 and the correlations between Doppler S/D ratio and placental vascular resistance in the acute and chronic situations were .86 and .339, respectively. This preliminary data suggest that flow velocity waveforms are independent of the method used and that remarkable differences occur in the placental microcirculation during acute and chronic embolization.

Animals↗
PubMed1989

Duplex ultrasonography of the fetal aorta, umbilical artery, and placental arcuate artery throughout normal human pregnancy.

A cross-sectional duplex study of blood flow in the fetal aorta, umbilical artery, and arcuate arteries of 111 normal subjects was performed once at between 20 and 42 weeks gestation. Peak systolic velocity, end-diastolic velocity, mean velocity, and volume flow were measured in the fetal aorta, and systolic to diastolic (S/D) ratios were measured in all three vessels. Velocities show an inverse exponential (Y = Exp [1/X x B + C]) increase with gestational age, reaching a plateau just before term, while S/D ratios in the aorta and umbilical arteries show a linear decrease. Such findings are at variance with some published data. Our results suggest a reduction in fetal placental resistance at term and provide useful data concerning normal fetal and placental circulations.

Aorta↗
PubMed1988

Pulmonary hypoplasia testing in clinical obstetrics.

An ultrasound-based diagnostic test for predicting pulmonary hypoplasia antenatally by measurements of fetal chest circumference was applied prospectively to 45 patients at risk for developing this disorder. The outcome for the newborn infant and the autopsy findings were correlated with the antenatal prediction. The results of this test demonstrated a sensitivity and a specificity of 88% and 96%, respectively. The application of this test to clinical practice is recommended.

Amniotic Fluid↗
PubMed1988

Evaluation of fetal cardiac dysrhythmias with two-dimensional, M-mode, and pulsed Doppler ultrasonography.

Forty-three patients with fetal cardiac dysrhythmia were referred to a tertiary ultrasound department for further evaluation. The patients were subdivided according to the type of dysrhythmia diagnosed. All patients with irregular fetal heart rate had a good perinatal outcome. Of the six patients with fetal tachycardia, two required in utero therapy with maternal digoxin, and one of these fetuses had a cardiac tumor. The eleven patients with fetal bradycardia had the worst perinatal outcome, with four deaths occurring. The results suggest that all patients with fetal tachycardia or bradycardia should have a complete fetal cardiac assessment in a center experienced with the management of such cases.

Algorithms↗
PubMed1988

Birth patterns: are the Chinese in Guangzhou City different?

Diurnal birth patterns in the City of Guangzhou, China and the City of Calgary in Canada were compared. Chinese data were abstracted from the labor room log book of one large general hospital located in the Hai Zhu district of Guangzhou. Calgary birth data were abstracted from birth notification forms submitted to Calgary Health Services. Information included day of birth, time of delivery, type of delivery and parity. Calgary births are concentrated on Tuesdays to Fridays whereas in Guangzhou weekly patterns varied tremendously according to whether it was assisted or unassisted. Calgary births are below average at night and during evening shift. The time of birth in Guangzhou varied substantially with above average rates for non-assisted births noted at 0800-2400 h, and above average rates for assisted births noted at 0800-1700 h. Differences in hour of birth appeared to be related to obstetric intervention practices. Knowledge of birthing patterns are useful for effective hospital management.

Canada↗
PubMed1988

Atrial natriuretic peptide production in association with nonimmune fetal hydrops.

The presence and elevation of atrial natriuretic peptide in fetuses has not previously been demonstrated. This study of right atrial pacing in fetal lambs demonstrated a threefold to fourfold increase in atrial natriuretic peptide during the production of fetal hydrops. Its rate of return to a normal level paralleled the clearance of fetal hydrops. Its possible role in fetal cardiovascular hemodynamics is discussed.

Animals↗
PubMed1987

Clinical utility of multiple-dose administration of prostaglandin E2 gel.

An open-label study was undertaken to assess the clinical impact of multiple doses of intracervical prostaglandin E2 (0.5 mg) gel administered at 6-hour intervals. Fifty women with low Bishop scores requiring induction of labor were recruited. The prestudy mean Bishop score was 2.3 +/- 1.1 and changed significantly with one (p less than 0.001), two (p less than 0.001), and three (p less than 0.002) doses. The mean gestational age of patients receiving three doses was significantly less than that of patients receiving one dose, (38.5 versus 40.1 weeks, p less than 0.005). Prostaglandin E2 gel induced labor in 56% of patients, but 14% required subsequent oxytocin (Syntocinon) augmentation. Cesarean section was performed in 6% of patients. No deleterious fetal, neonatal, or maternal effects occurred.

Adult↗
PubMed1987

Doppler ultrasound prediction of fetal outcome in twin pregnancies.

The usefulness of pulsed Doppler ultrasound in predicting twin pregnancies destined for unsatisfactory outcomes was examined in 30 twin pregnancies. Fetal flow velocity waveform analysis (systolic/diastolic ratio and pulsatility index) and quantitative analysis in the descending aorta and umbilical artery demonstrated good sensitivity and specificity when compared with biparietal diameter and abdominal circumference measurements. This technique shows some promise as a useful adjunct in the management of twin pregnancies.

Aorta, Thoracic↗
PubMed1987

Ultrasound evaluation of tachycardia-induced hydrops in the fetal lamb.

Nonimmune hydrops was induced in six fetal lambs at 120 days' gestation by right atrial pacing at 300 beats/min. Biochemical, hemodynamic, and Doppler parameters were observed and monitored by real-time ultrasound during the creation (18 to 42 hours) and resolution of hydrops. The significant changes seen were hypoproteinemia (34.3 to 29.0 mg/100 ml), venous hypertension (24.6 to 31.3 mm Hg), decreases in thoracic aorta flow, and decreases in systolic/diastolic ratios in the aorta and umbilical artery. These changes were reversed with the discontinuation of pacing and the resolution of fetal hydrops.

Animals↗
PubMed1986

Ultrasound prediction of pulmonary hypoplasia.

Normograms for ultrasound-measured fetal chest and heart circumferences were constructed from 83 normal pregnancies of 24 to 39 weeks' duration. Of six cases at risk for pulmonary hypoplasia, all of whom ultimately proved to have the condition, four fell below the fifth percentile for chest circumferences. Both cases in which the chest circumference was within the normal range had pleural effusions.

Cross-Sectional Studies↗
PubMed1985

Intrauterine hydrocephalus and ventriculomegaly: associated anomalies and fetal outcome.

Advances in fetal diagnostic techniques have opened many areas to prenatal anatomical scrutiny. Intrauterine hydrocephalus and ventriculomegaly are conditions which are readily diagnosed. Fetal intervention has been undertaken in humans in order to minimize the craniofacial disfigurement and to maximize the growth potential of the brain. To justify such an approach, the significance of all anomalies should be recognized prior to treatment. The authors have reviewed 41 cases of hydrocephalus diagnosed in utero in order to define associated anomalies and patient outcome. 75% of our personal series and 72% of the reviewed literature cases had other anomalies of the central nervous system. Other system malformations, some of which proved fatal, were seen commonly. Prenatal diagnostic techniques did not always reveal these additional problems. The outcome of these pregnancies is not good. Approximately one third of these fetuses have survived to be treated postnatally and to be followed up clinically. Only 7.5% of this series were felt to have attained normal developmental milestones. The remainder of the survivors have various focal and/or global cerebral deficits.

Abnormalities, Multiple↗
PubMed1984

In utero evaluation of fetal cardiac structure: a preliminary report.

Fetal echocardiography as a tool for the prenatal diagnosis of cardiac structural abnormalities was utilized in 27 consecutive patients who were referred for evaluation. Four abnormalities were recognized prenatally and confirmed postnatally. A fifth was identified postnatally. The sensitivity and specificity of this diagnostic test were 80% and 100%, respectively. The utilization of this tool in a tertiary care setting by an adequately trained team has proved to be helpful and is recommended.

Echocardiography↗