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R L Deter

Publications and source records attributed to R L Deter.

At least 73 records · Page 4Linked to original sources
PubMed1987

Prenatal diagnosis and postnatal management of critical aortic stenosis.

Fetal echocardiography has yet to have an impact on the treatment of congenital heart disease. Critical aortic valve stenosis was diagnosed by echocardiography before birth in a 35 week gestation fetus. The risks to the fetus and mother associated with prolonged rupture of membranes prompted their transport to a hospital with cardiac surgical and high-risk perinatal facilities. Prenatal and postnatal echocardiographic findings agreed regarding the diagnostic criteria for critical aortic stenosis and primary forms of cardiomyopathy were excluded. Results of fetal Doppler examination were consistent with valvular aortic stenosis and excluded mitral regurgitation. Determination of the left ventricular size excluded ventricular hypoplasia. The infant was delivered by cesarean section and underwent successful emergency aortic valvotomy at 12 h of age. Fetal echocardiography, in combination with a multidisciplinary postnatal approach, can be used in the successful treatment of a severe form of congenital heart disease.

Aortic Valve Stenosis↗
PubMed1987

A simplified method for determining individual growth curve standards.

To simplify the procedure for obtaining individual growth curve standards, we investigated the use of models derived from the slopes of growth curves determined before 26 weeks' menstrual age. In serial examinations of 33 normal fetuses between 15-38 weeks, we obtained measurements of the biparietal diameter (BPD), head circumference, abdominal circumference, femur diaphysis length, head profile area, abdominal profile area, head cube, and abdominal cube. Rossavik models fitted to these data provided estimates of the coefficients c and s, and fitting linear models to the data before 26 weeks gave estimates of growth curve slopes. Slopes were also estimated from two data points at approximately 16 and 25 weeks. Regression analysis demonstrated a strong linear relationship between loge c and loge SLOPE1 (R2 = 87.3-98.4%), and between s and c (R2 = 64.9-90.3%). Using these relationships, growth models were determined from the slope values. Comparisons between observed measurements and those predicted by these models for the period after 26 weeks indicated that the methods of slope calculation were equally accurate in predicting future growth, and that this accuracy was very similar to that obtained with models based on regression analysis. These results demonstrate that individual growth curve standards for at least eight anatomic parameters during the last 14 weeks of pregnancy can be determined from the data obtained in two examinations before 26 weeks' menstrual age.

Embryonic and Fetal Development↗
PubMed1986

Evaluation of fetal thigh circumference measurements: a comparative ultrasound and anatomical study.

This investigation is concerned with establishing the anatomical location of the site proposed for making fetal thigh circumference (ThC) measurements with ultrasound. An evaluation of the accuracy of ultrasonic ThC measurements has also been made. The results of these studies indicate that the change in femur profile (polygonal to oval) used to identify the site of measurement (transition plane) occurs at the junction of the upper and middle thirds of the thigh, at the level of the proximal nutrient foramen of the femur. Ultrasonic ThC measurements are systematically larger (mean: 4.3%; range: 1.3-10.3%) than comparable anatomical measurements. Measurements made within 1-2 cm of the transition plane are quite similar, demonstrating that exact positioning of the plane is not necessary. These results indicate that ThC measurements can be made in a reliable manner and thus could be used to detect changes in soft tissue mass and improve weight estimation procedures.

Female↗
PubMed1986

Fetal thigh circumference: a critical evaluation of its relationship to menstrual age.

To provide standards for evaluating fetal thigh circumference measurements obtained with ultrasound, a study of the growth of this parameter during pregnancy was made. Because of possible sampling problems before 22 weeks (menstrual age), this investigation was limited to the 22-40 week time period. Regression analysis indicated that the optimal model (R2 = 88.9%) for describing thigh circumference (ThC) growth was a power function. ThC variability increased with menstrual age, from 1.3 cm at 22 weeks to 3.1 cm at 40 weeks. These data were used to construct a standard growth curve for the ThC.

Female↗
PubMed1986

Efficacy of mathematical methods for ultrasound examinations in diabetic pregnancies.

The efficacy of a new principle for evaluation of fetal growth has been compared to standard methods in a population of pregnant diabetic women. Methods for projecting fetal weight at birth and determining the deviation of growth from an expected fetal weight increase based on our growth model provided significant information for the detection of fetal growth abnormalities 3 weeks (mean) before delivery. (Large for gestational age: sensitivity, 81%; specificity, 85%. Small for gestational age: sensitivity, 100%; specificity, 98%.) With the exception of two models for estimation of fetal weight based on ultrasound measurements of the fetal head and abdomen only, none of the standard methods gave results that were significantly better than the use of the biparietal diameter against a population standard. The new methods are expected to provide valuable information for the treatment of fetal growth disorders.

Anthropometry↗
PubMed1986

Fetal ventricular pacing for hydrops secondary to complete atrioventricular block.

The advent of ultrasound recording has expanded the capabilities for treatment of the fetus in utero. The diagnosis of specific disease processes has allowed for prenatal intervention by new techniques designed to improve fetal survival. The application of ventricular pacing in a hydropic fetus with complete atrioventricular (AV) block is reported. Complete AV block resulted from maternal collagen vascular disease. The application of ventricular pacing was to allow for further in utero development and for reversal of hydrops fetalis after improvement in cardiac output. Despite fetal death 4 hours after placement of the ventricular pacing lead, this procedure when applied earlier in the development of hydrops may allow for fetal survival. Ventricular pacing was accomplished without apparent trauma to mother or fetus and no evidence of fetal injury was seen at necropsy. Therefore, in the fetus who would otherwise die in utero before the point of viability ex utero, fetal ventricular pacing may be a rational alternative to current observation.

Adult↗
PubMed1986

Mathematic modeling of fetal growth: development of individual growth curve standards.

To provide a more precise means for monitoring individual fetal growth and to improve the detection of growth abnormalities, the Rossavik growth model [P = c(t)k + s(t)] has been used to establish individual growth curve standards. A longitudinal study of the growth of one-dimensional (biparietal diameter, head, and abdominal circumferences), two-dimensional (head and abdominal profile areas), and three-dimensional (head and abdominal volumes) parameters in 18 normal fetuses has revealed that the growth of all parameters can be well-described by the Rossavik model (R2: 97.2 to 99.5%). Strong statistical evidence was obtained indicating that the coefficient k is principally a geometric coefficient having a value determined primarily by the dimension of the parameter being studied. It was also found that the coefficients c and s can be estimated from the data obtained before 28 weeks' conceptual age. Individual growth curve models derived from data obtained before 28 weeks were capable of predicting growth beyond 28 weeks. These models provide growth curve standards for evaluating individual fetal growth beyond 28 weeks.

Embryonic and Fetal Development↗
PubMed1985

Estimation of fetal weight with the use of head, body, and femur measurements--a prospective study.

In utero estimates of fetal weight were evaluated prospectively in 109 fetuses with the use of sonographic models developed in a previous study. This report confirms that the best in utero weight estimates result from the use of models based on measurements of head size, abdominal size, and femur length. Since the accuracy of these models (1 SD = 7.5%) is significantly better than those based on measurements of head and body (e.g., biparietal diameter, abdominal circumference), we recommend routine use of such models in obstetric sonography.

Abdomen↗
PubMed1985

Use of ultrasound in the detection of macrosomia: a review.

The early detection of the macrosomic fetus is important to the obstetric management of pregnancies in which this growth abnormality occurs. Ultrasound has been used for this purpose but for this approach to be effective, a clear definition of macrosomia, selection of the appropriate parameters for measurement, and specification of the optimal time for carrying out the ultrasound studies are required. In this review we examine the definition of macrosomia and introduce two new terms, mechanical macrosomia and metabolic macrosomia. We also evaluate the effectiveness of the limited number of parameters studied to date and conclude that they are marginally effective, primarily because of their low sensitivity and the limitations of current ultrasound methods for estimating fetal weight. The use of the growth profile, a multiparameter approach to the evaluation of fetal growth, is suggested as a possible means for improving the effectiveness of ultrasound in detecting the macrosomic fetus.

Birth Weight↗
PubMed1985

Use of femur length/abdominal circumference ratio in detecting the macrosomic fetus.

The femur length/abdominal circumference ratio, expressed as FL/AC X 100, was determined in 156 fetuses and evaluated as a predictor of fetal macrosomia within one week prior to delivery. The normal range (mean +/- 2 SD) in the 105 normal-weight fetuses was 22.0 +/- 2, while the normal range in the 51 macrosomic fetuses was 20.5 +/- 2; these differences were highly significant (P = less than .0001). The predictive power of a positive ratio was 68%, with a sensitivity of 63%. This ratio was particularly useful in the subset (n = 9) of macrosomic fetuses whose mothers were diabetic, correctly identifying 89% of this group. Because it is age independent, this ratio should prove most helpful in identifying fetuses at risk for macrosomia in patients whose dates are not known, since it may become abnormal before the fetal weight falls above the 90th percentile at term (3,900 g). In patients whose dates are known, early fetal macrosomia is best predicted by evaluating the abdominal circumference against normal standards for age.

Abdomen↗
PubMed1985

Ultrasound prediction of fetal lung maturity.

Amniocentesis for determination of fetal lung maturity and ultrasonographic (US) evaluation of the biparietal diameter (BPD) and placental grade were performed simultaneously in 261 nondiabetic pregnant women. A BPD of at least 9.3 cm and a grade 3 placenta were evaluated as predictors of fetal lung maturity using amniotic fluid phospholipids as indicators of a mature lung profile. The ability of the sonographic parameters to predict fetal lung maturity was closely related to menstrual age. Before 37 weeks, the false-positive prediction rate using a grade 3 placenta was 100%, and the false-positive prediction using the BPD was 85.6%. After 37 weeks, the false-positive rate using a grade 3 placenta was 5.9%, and the false-positive rate using the BPD was 9.5%. Thus menstrual age, and not these two US parameters, dictated fetal lung maturity. The authors conclude that the best use of US for predicting fetal lung maturity is in establishing menstrual age early in pregnancy.

Adult↗
PubMed1985

Fetal femur length: a critical reevaluation of the relationship to menstrual age.

This investigation has reexamined the measurement of the femur length and the use of this measurement as a growth and dating parameter. Straight-line measurements of shaft length were found to be smaller than measurements made along the bone curvature. However, the maximum difference did not exceed 2 mm. Thus, because of its simplicity, use of straight-line measurements appears justified. The optimal (R2 = 96.1%) growth curve model was a linear-quadratic function, with variability around the regression line increasing with menstrual age. The optimal (R2 = 96.8%) dating curve model was a linear-quadratic function in which loge menstrual age is a function of femur length. The variability associated with age estimates increased with femur length. These data were used to construct new standard curves for growth assessment and dating of fetuses using femur length measurements.

Cephalometry↗
PubMed1984

The effect of intrauterine malnutrition on the term infant. A 14-year progressive study.

The developmental outcome of 33 newborn infants with clinical intrauterine malnutrition at birth and 13 clinically well nourished infants from a middle to high socio-economic population have been followed from birth to 12-14 years of age. Psychometric studies revealed a lowering of the IQ score in malnourished infants compared to well nourished infants (104 +/- 15 compared to 121 +/- 13, p less than 0.05) and a need for special education (p less than 0.03). Forty-five percent of the malnourished infants' birth weights were above the 10th percentile on the Colorado Intrauterine Growth Grid. The Full Scale IQ of malnourished infants with BW greater and less than 10th percentile on the Colorado Intrauterine Growth Grid were comparable. Malnourished infants with birth weights greater than 10th percentile had lower IQ scores than well nourished infants (101 +/- 13 compared to 121 +/- 13, p less than 0.006). Thirty-nine percent of the infants with handicaps would have been missed if only infants with birth weights less than 10th percentile were considered high risk.

Adolescent↗
PubMed1984

Sonographic estimation of fetal weight. The value of femur length in addition to head and abdomen measurements.

Sonographic estimation of fetal weight in utero was performed in 167 live-born fetuses examined within one week of delivery. Regression models were based on measurements of abdominal circumference, head circumference, biparietal diameter, and femur length, both alone and in combination. The best results (1 S.D. = 7.5% of actual weight) were obtained by combining measurements of the fetal head, abdomen, and femur, most likely due to the strong linear relationship between femur length and crown-heel length.

Abdomen↗
PubMed1984

Estimating fetal age: computer-assisted analysis of multiple fetal growth parameters.

Regression models for predicting menstrual age based on real-time sonographic measurements of four fetal parameters (biparietal diameter, head circumference, abdominal circumference, and femur length), used alone and in combination, were developed in a cross-sectional study of 361 fetuses between 14 and 42 menstrual weeks. The head circumference and femur length were the strongest individual predictors of age. A number of combinations of fetal parameters, including the combination of head circumference and femur length, provided age estimates that were significantly better (p = 0.05) than those using any single parameter alone. It was also demonstrated that simply averaging individual age estimates in a given case could provide results that were not significantly different from those obtained by using the same parameters in a complex regression equation. The advantages and potential pitfalls of this system of fetal dating are discussed.

Abdomen↗