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At least 451 records · Page 25Linked to original sources
PubMed1997

Comparison of second trimester biometry in singleton and twin pregnancies conceived with assisted reproductive techniques.

The objective of this study was to investigate the size of singleton vs twin pregnancies at the time of a second trimester dating scan. The analysis included 86 infants from 63 pregnancies achieved with assisted reproductive techniques, comprising 40 singletons and 46 twins. Measurements of second trimester biparietal diameter (n = 85) and femur length (n = 74) were plotted against the precisely known gestational age. A common regression line was calculated for each parameter and the residuals for singletons and twins were compared. Gestational age and weight at birth were also analysed for each group. There was no significant difference between singletons and twins in biparietal diameter or femur length in second trimester. In contrast, twins had a lower mean birthweight, gestational age at birth, and weight-for-gestational age centile compared with singletons. Singleton babies from these pregnancies had an average birthweight centile of 49.8% (i.e. close to the median for spontaneously conceived pregnancies in our population). We concluded that the same pregnancy dating charts can be used for singletons and twins. At corresponding gestational age, twins are smaller than singletons at birth because of slower growth in the third trimester.

Anthropometry↗
PubMed1995

Screening for the small fetus: a study of the relative efficacies of ultrasound biometry and symphysiofundal height.

In this study 3 different methods of screening for birth-weight < 10th percentile in pregnancy were evaluated both individually and in combination; 1,135 women with singleton pregnancies were studied. Measurements of symphysiofundal height by tape measure, and amniotic fluid index and fetal abdominal circumference by ultrasound imaging, were made at 18, 24, 28, 34 and 38 weeks. At none of these gestational ages did amniotic fluid index perform well as a screening test for birth-weight < 10th percentile. Combining the tests, using symphysiofundal height to select a group at high risk who then had a fetal abdominal circumference measurement, reduced the false positive rate but significantly decreased the percentage of infants diagnosed. The results of this study confirm that the most appropriate antenatal diagnostic test for birth-weight <10th percentile is ultrasound measurement of fetal abdominal circumference. Selecting pregnancies at risk by clinical measurement of symphysiofundal height will provide a lower false positive rate than a policy of performing ultrasound on all pregnancies during the third trimester, but will also reduce the sensitivity.

Adult↗
PubMed2004

Quantitative evaluation of changes in anterior segment biometry by peripheral laser iridotomy using newly developed scanning peripheral anterior chamber depth analyser.

AIM: Using the newly developed scanning peripheral anterior chamber depth analyser (SPAC), the effects of peripheral laser iridotomy (PLI) on peripheral anterior chamber depth (PACD) were determined quantitatively as was the association between PACD and chronic elevation of intraocular pressure (IOP) after PLI. METHODS: 16 eyes of 15 patients with acute primary angle closure glaucoma (PACG) attack, 14 eyes of 14 patients with narrow angle and PACG attack in their fellow eyes, and 13 eyes of seven patients with chronic angle closure glaucoma (CACG) were enrolled. The SPAC scanned the anterior ocular segment from the optical axis to the limbus and took 21 consecutive slit lamp images at 0.4 mm intervals. A computer installed program automatically evaluated the PACD and the averaged values of three measurements were employed for analysis. RESULTS: PLI significantly increased PACD and changed the iris contour from convex to flat or concave in all the enrolled eyes. The extent of the PLI induced PACD increase was enhanced with increasing distance from the optical axis. Comparing PACDs after PLI, eyes that received prophylactic PLI showed the greatest extent of PLI induced PACD increase, followed by eyes with CACG and eyes with PACG attack. The PACD of eyes with PACG attack was almost the same as that of the fellow eyes of PACG attack before prophylactic PLI. Eyes with PACG attack showed poorer IOP control after PLI than eyes with narrow angle and CACG with PLI. CONCLUSIONS: PLI significantly increases PACD and the small PLI induced opening of PACD may contribute to chronic IOP elevation after PLI.

Aged↗
PubMed2002

Prenatal ultrasound biometry related to subsequent blood pressure in childhood.

STUDY OBJECTIVE: To relate measures of fetal growth/size other than birth weight with subsequent blood pressure measured on the same individuals within the context of the "fetal origins of adult disease". DESIGN: A prospective cohort study in which measurements of fetal dimensions obtained by serial ultrasound imaging between 18 and 38 weeks gestation were analysed with reference to systolic blood pressure measurements on the offspring at age 6 years. SETTING: Perth, Western Australia. PARTICIPANTS: A subgroup of 707 eligible mother-fetus pairs from a cohort of 2876 pregnant women and their offspring. The number of mother-fetus pairs varied at each gestational age and by measurement of fetal dimension. Subsequent blood pressure recordings were obtained on approximately 300 of the offspring at age 6 years. MAIN RESULTS: The findings confirmed the inverse association between birth weight and systolic blood pressure at age 6. There was, also, an inverse relation between fetal femur length and systolic blood pressure at age 6, adjusted for current height. Furthermore, an inverse association was demonstrated between a statistically derived measure of fetal growth (conditional z score) between 18 and 38 weeks gestation and later systolic blood pressure at age 6. The effect sizes for all three relations were in the order of 1-2 mm Hg per standard deviation change. CONCLUSION: The mechanisms underpinning the "fetal origins" hypothesis may be operative early in pregnancy and may be reflected in the length of the fetal femur in early to mid-pregnancy.

Anthropometry↗
PubMed1983

Biometry of the anterior eye segment by Scheimpflug photography.

Scheimpflug photos of 262 cataract patients, classified according to various forms of opacifications characteristic for senile cataracts were evaluated by biometric methods. The measured values on cornea thickness, depth of anterior chamber, lens thickness, and radii of curvatures of cornea and anterior lens surface show that a correlation between some of the parameters and certain forms of opacities must be assumed.

Adolescent↗
PubMed1991

Optical problems of anterior chamber depth biometry by scheimpflug photography.

For the first time, the Scheimpflug camera was used in the comparative investigation of the anterior chamber depth. Comparative measurements were carried out by a device developed by Jaeger, a clinically and scientifically proved method in anterior chamber depth determination. The physical problems of measuring the anterior chamber depth by using optical methods can be shown by the examination demonstrated here. The apparent change of the cornea profile depending on the cornea radius, which you can see in optical investigations, schematically described by Collignon-Brach, can be represented photographically by the Scheimpflug image.

Adolescent↗
PubMed1982

Prediction of fetal growth deviation by ultrasonic biometry. I. Methodology.

Early information of impaired or accelerated fetal growth is of importance for antenatal care. The present study has produced a mathematical formula which in the 33rd week of pregnancy permits prediction of fetal weight deviation at birth. The prediction was based on two ultrasonic examinations: in the 17th week of pregnancy the biparietal diameter (BPD) was measured to assess the fetal gestational age; in the 33rd week of pregnancy, BPD and the abdominal diameter (AD) of the fetus were measured. Fetal growth deviation was then described by comparing the assessed BPD and AD with the expected mean values for the gestational age on the day of this measurement. For 872 fetuses the growth deviation found in the 33rd week was related to the fetal weight deviation at birth; multiple regression analyses were performed and a mathematical formula developed. For practical purposes this formula is expressed in a nomogram.

Abdomen↗
PubMed1994

Fetal biometry of skeletal dysplasias: a multicentric study.

Twenty-three diagnostic centers worldwide contributed 127 cases of 17 skeletal dysplasias. Discriminant analysis showed that the femur length was the best biometric parameter to distinguish among the five most common disorders in this series (thanatophoric dysplasia, osteogenesis imperfecta type II, achondrogenesis, achondroplasia and hypochondroplasia). Fifty-four percent of fetuses with femur length below 30% of the mean for gestational age had achondrogenesis. Seventy-eight percent of measurements between 40 and 60% of the mean for gestational age represented either thanatophoric dysplasia or osteogenesis imperfecta type II. Fetuses who had over 80% of the mean for gestational age had predominantly hypochondroplasia, achondroplasia, and osteogenesis imperfecta type III.

Anthropometry↗
PubMed1994

Fetal biometry of skeletal dysplasias: a multicentric study.

Twenty-three diagnostic centers worldwide contributed 127 cases of 17 skeletal dysplasias. Discriminant analysis showed that the femur length was the best biometric parameter to distinguish among the five most common disorders in this series (thanatophoric dysplasia, osteogenesis imperfecta type II, achondrogenesis, achondroplasia and hypochondroplasia). Fifty-four percent of fetuses with femur length below 30% of the mean for gestational age had achondrogenesis. Seventy-eight percent of measurements between 40 and 60% of the mean for gestational age represented either thanatophoric dysplasia or osteogenesis imperfecta type II. Fetuses who had over 80% of the mean for gestational age had predominantly hypochondroplasia, achondroplasia, and osteogenesis imperfecta type III.

Bone Diseases, Developmental↗
PubMed1994

Evaluation of pulsatility index nomograms based on fetal biometry in small for gestational age fetuses.

Reference limits for the PI from the umbilical, middle cerebral, and renal arteries were constructed using BPD, AC, FL, and transverse cerebellar diameter as independent variables and their efficacy tested in a population of SGA fetuses. Therefore, 153 normal fetuses and 90 SGA fetuses with established dates between 20 and 40 weeks of gestation were considered. Normal fetuses showed a linear negative relationship between the PI from all the vessels investigated and all the biometric parameters considered. Although the BPD related better with the PI from the umbilical artery (r = 0.646) and the renal artery (r = 0.765) and the transverse cerebellar diameter related better with middle cerebral artery PI values (r = 0.510), no evident differences in fitting were found among the variables tested. In SGA fetuses the nomograms on BPD, AC, and FL significantly underestimated PI values in all the vessels studied when compared to the nomograms based on gestational age, while a similar ability in identifying abnormal PI values was found for nomograms based on gestational age and transverse cerebellar diameter. These newly developed nomograms based on transverse cerebellar diameter may prove useful in the evaluation of Doppler indices of fetuses with uncertain gestational age.

Embryonic and Fetal Development↗