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Biomedical subjects

L D Platt

Publications and source records attributed to L D Platt.

At least 109 records · Page 6Linked to original sources
PubMed1989

Role of ultrasound in urinary incontinence evaluation.

Transrectal ultrasound was used to assess anatomic support of the urethrovesical junction (UVJ) in continent and stress incontinent women. UVJ drop on straining of less than 1 cm as assessed by transrectal ultrasound correlated well with good support to the UVJ. Drop of UVJ of more than 1 cm on straining correlated with poor support to bladder neck and stress urinary incontinence. The transrectal technique is quick and easy to perform and interpret.

Female↗
PubMed1989

A prospective trial of the femur length to abdominal circumference ratio to predict the outcome of preterm labor.

Femur length to abdominal circumference ratio was used to predict the adequacy of fetal growth for patients undergoing treatment for preterm labor. When quantitated in this way, no correlation could be found between fetal growth and effectiveness of tocolytic therapy. Despite its correlation in retrospective studies, poor fetal growth was not correlated with preterm delivery to any measurable extent in this prospective trial.

Abdomen↗
PubMed1989

Monocyte monolayer assay: an efficient noninvasive technique for predicting the severity of hemolytic disease of the newborn.

The authors performed monocyte monolayer assays (MMAs) with the use of normal donor monocytes, and homologous reagent red blood cells, sensitized in vitro, with antibodies in maternal sera. The sera were from 16 pregnant women with Rh antibodies, drawn at the time of amniotic fluid analysis. They compared the predictive value (PV) of the MMAs and the delta OD 450 of amniotic fluid in forecasting the need for transfusing the infant. The PV of the delta OD 450 result in Liley zone mid II-III was 100%, but in zones 0 to low II it was only 60% (13 samples from ten women were in these zones but four babies required transfusion). In contrast, the PV of a positive (greater than 20% reactivity) MMA was 91% (one false positive result) and the PV of a negative MMA was 100%. Thus, the MMA was more efficient than amniotic fluid analysis at predicting hemolytic disease of the newborn severe enough to require transfusion. The noninvasive MMA could be used as a screening test, reducing the number of amniocenteses or ultrasound evaluations performed on Rh-sensitized women.

Amniotic Fluid↗
PubMed1989

Cerebral, umbilical, and uterine resistance using Doppler velocimetry in postterm pregnancy.

The purpose of this study is to assess alterations in vascular resistance as measured by Doppler ultrasound in the postterm fetus. Forty-five postterm patients (greater than or equal to 287 days gestation by "good" dates) underwent Doppler velocimetry and calculation of systolic to diastolic (S/D) ratios of the umbilical, internal carotid, and uterine artery waveforms within 7 days of delivery. Patients were divided into two groups. Group 1 consisted of 26 patients with normal antepartum fetal surveillance that included reactive nonstress test and an amniotic fluid index (using the four-quadrant technique) equal to or greater than 5 cm. Group 2 consisted of 19 patients with antepartum compromise on the antepartum fetal surveillance tests. There was significantly greater (p less than .05) morbidity in group 2 compared to group 1 as judged by cesarean section for fetal distress (47% vs 15%), meconium at delivery (53% vs 4%), and 5-minute Apgar score less than 7 (30% vs 4%). There were no significant differences in the umbilical and uterine artery S/D ratios in the two groups, although patients in group 2 had significantly lower cerebral S/D ratios (3.6 +/- .5) compared to group 1 (4.4 +/- 0.4) (p less than .05). The ratio of cerebral to placental (umbilical) resistance in group 2 was significantly lower (1.1 +/- .3) compared to group 1 (1.8 +/- .3) (p less than .05). There was a low incidence of abnormal umbilical (greater than 3) and uterine (greater than 2.6) S/D ratios in both groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Blood Flow Velocity↗
PubMed1989

Placental vascular resistance using umbilical velocimetry in patients undergoing cesarean section for fetal distress.

Peak systolic (S) to lowest end-diastolic (D) ratios (S/D) of umbilical velocimetry have been used to assess downstream placental vascular resistance and predict adverse pregnancy outcome. The purpose of this study is to assess S/D ratios in patients undergoing cesarean section for clinical fetal distress. Fifty-six patients were identified who had umbilical velocimetry performed during antepartum fetal surveillance (nonstress testing and amniotic fluid index) within 7 days of undergoing cesarean section for fetal distress at Women's Hospital (Los Angeles, CA). The mean gestational age at delivery was 36.5 +/- 2.5 weeks. Thirty (53.6%) patients had elevated S/D ratios (greater than 3), 24 (42.9%) had abnormal amniotic fluid indices, and 20 (35.7%) had abnormal nonstress testing. Group 1 (N = 30) patients delivered small-for-gestational-age (SGA) fetuses and group 2 (N = 26) patients delivered appropriately grown (AGA) fetuses. In group 1, 24 (80%) patients had abnormal S/D ratios and 16 (53.3%) had abnormal amniotic fluid indices, compared to only 6 (23.1%) with abnormal S/D ratios and 8 (30.8%) with abnormal amniotic fluid indices in group 2 (p less than .05). In contrast, 14 (53.8%) of the 26 patients in group 2 had abnormal nonstress testing compared to only 6 (20%) of the 30 patients in group 1 (p less than .05). Eighteen (69.2%) of the 26 patients in group 2 were post-term pregnancies; 20 (66.7%) of the 30 patients in group 1 had chronic hypertension, pregnancy-induced hypertension, or superimposed preeclampsia.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1989

The diagnosis of immature teratoma by maternal serum alpha-fetoprotein screening.

We report a case in which maternal serum alpha-fetoprotein (MSAFP) screening of a low-risk patient led to the antepartum detection of an asymptomatic and previously undetected stage Ia immature teratoma of the ovary. It is widely accepted that MSAFP screening is valuable in the antepartum diagnosis of neural tube defects, ventral wall defects, and aneuploid fetuses. Similarly, such screening may lead to the diagnosis of AFP-producing neoplasms not appreciated on physical or ultrasonic examinations. This benefit, though extremely rare, is significant when a potentially aggressive malignancy is detected in the earliest stages, prior to extraovarian spread.

Adult↗
PubMed1989

Fetal umbilical blood flow velocity waveforms using Doppler ultrasonography in patients with late decelerations.

The purpose of this study was to assess placental vascular resistance as measured by peak systolic to end-diastolic ratios (S/D) of the umbilical artery waveforms in patients with late decelerations. Fifty patients with persistent late decelerations and 50 gestational age-matched controls with reactive tracings underwent umbilical velocimetry with measurement of S/D ratios. The mean (+/- SD) S/D ratio in the late-deceleration group (4.32 +/- 1.1) was significantly higher than that of the control group (2.32 +/- 0.21) (P less than .01). Patients with late decelerations had a significantly higher incidence of adverse pregnancy outcome, as judged by the incidence of small for gestational age infants, meconium, cesarean section for fetal distress, low Apgar scores, and neonatal intensive care unit admissions, compared with the control group. However, there was no difference in the incidence of adverse pregnancy outcome in the late-deceleration group with normal S/D ratios compared with controls. The sensitivity, specificity, and positive and negative predictive values of S/D ratios in the late-deceleration group for predicting adverse pregnancy outcome were 85.7, 100, 100, and 89.6%, respectively. These data suggest that umbilical velocimetry might be able to discriminate late decelerations that constitute a false-positive test. Incorporation of umbilical velocimetry into antepartum and intrapartum fetal surveillance schemes may therefore be helpful.

Adult↗
PubMed1989

Acute puerperal uterine inversion. New approaches to management.

A retrospective review identified 56 patients with uterine inversion, from July 1977 through June 1986, from weekly obstetric statistics, delivery records and computerized discharge diagnoses. All patients underwent delivery by house officers, midwives or medical students under supervision. An analysis of the data revealed that the risk factors were primiparity, a fundally implanted placenta and delivery of a macrosomic fetus. Also, patients who received oxytocin with or without MgSO4 were at higher risk of puerperal inversion. MgSO4 by itself did not appear to be a risk factor. A placenta attached at the time of inversion appeared to have a protective effect against the development of shock. The use of betamimetics or MgSO4 appeared to be an acceptable alternative to general anesthesia in relaxing the uterus and aiding in its repositioning. Those agents were more likely to be successful in acute cases than in subacute ones and in second-degree inversion than in third-degree.

Adolescent↗
PubMed1988

Ultrasonic evaluation of urethrovesical junction in women with stress urinary incontinence.

An ultrasonic evaluation of the bladder base and urethrovesical junction, at rest and during stress, using a transrectal probe, was performed on 24 continent and 67 incontinent patients. Forty-four of the incontinent patients had clinical and urodynamic diagnoses of stress urinary incontinence and 23 patients had detrusor instability incontinence. Thirty-eight of the 44 patients (86%) with urodynamically and urethroscopically proven genuine stress urinary incontinence and a weak urethral sphincter had a urethrovesical junction (UVJ) drop during stress of greater than or equal to 1 cm (mean 1.3 cm +/- 0.6 cm), as demonstrated on transrectal ultrasonic evaluation. All 23 patients with detrusor instability and 22 of the 24 continent (control) patients had UVJ drop on straining of less than 1 cm (mean 0.48 cm +/- 0.23 cm and 0.54 cm +/- 0.29 cm, respectively, p less than 0.05). The sensitivity of ultrasonic evaluation of women with stress urinary incontinence (when 1-cm drop of UVJ is considered as the upper boundary of normal) was 86% and the specificity was 91%. This ultrasound technique is quick, simple, and appears to be accurate. We believe this technique should be considered in the preoperative evaluation of women with stress urinary incontinence.

Adult↗
PubMed1988

Prenatal detection of fetal thymidine kinase activity in maternal plasma: normal values and clinical application in postterm pregnancy.

Deoxythymidine kinase is present in human cells in two forms: the cytosolar form (fetal thymidine kinase) and the mitochondrial form (adult thymidine kinase). The activity of thymidine kinase isozymes in plasma of preterm and term newborns has been previously reported to be related to gestational age, and fetal thymidine kinase activity was reported to be undetectable after the thirty-ninth week of gestation. Our purpose was to determine if similar changes in the activity levels of the thymidine kinase isozymes could be demonstrated in late third trimester maternal plasma. A cross-sectional sample of 35 patients was studied from week 34 of pregnancy to delivery. Significant differences between fetal and adult thymidine kinase activity patterns were observed. Adult thymidine kinase activity remained relatively constant throughout the evaluation interval, while fetal thymidine kinase activity decreased with advancing gestational age. Regression analysis of gestational age by neonatal examination (GAPED) and fetal thymidine kinase revealed a linear relationship (fetal thymidine kinase = 0.380 - 0.00745 GAPED; R2 = 0.2944; standard estimate of error = 0.0350; p less than 0.0008). Comparison of fetal thymidine kinase activity in term and postterm pregnancy plasma revealed a significant difference (p less than 0.0159). Our findings indicate that deoxythymidine kinase activity can be measured in maternal plasma, may relate to the fetoplacental growth rate, and may be useful in differentiating between term and postterm gestations.

Embryonic and Fetal Development↗
PubMed1988

Qualitative assessment of maternal uterine and fetal umbilical artery blood flow and resistance in laboring patients by Doppler velocimetry.

The purpose of this study is to evaluate the effect of uterine contractions during labor on both the uterine and the umbilical circulations. Twenty-seven patients in active labor were studied by continuous-wave Doppler velocimetry. Umbilical, left uterine, and right uterine arterial waveforms were obtained before, during, and after peak uterine contractions, and the ratio of maximum systolic and minimum diastolic velocities was calculated. Fifteen patients showed absent flow in end diastole on the uterine artery waveform and had significantly higher intra-amniotic pressures (64.5 +/- 3.5 mm Hg) during the peak amplitude of the uterine contraction compared with the 12 patients with maintained end diastolic flow (46.5 +/- 2.6 mm Hg; p less than 0.05). During the peak amplitude of the uterine contractions the 12 patients maintaining end-diastolic flow had significantly higher systolic/diastolic ratios in the uterine artery (6.5 +/- 1.5) compared with either before or after a contraction (2.1 +/- 0.15 and 2.0 +/- 0.2, respectively; p less than 0.05). Also, these 12 patients showed a linear relationship between the systolic/diastolic ratio and the intrauterine pressure. However, no differences were observed in the umbilical artery systolic/diastolic ratios before, during, or after a contraction in the intensity range studied. On the contrary, during contractions an increase in uterine artery resistance occurs with decreased or absent end-diastolic flow, which bears an inverse linear relationship to the intensity of the contraction. This suggests that during uterine contractions the human fetus continues to have uninterrupted fetoplacental blood flow, whereas the degree of interruption or reduction in uteroplacental blood flow is dependent on the intensity of uterine contraction.

Adult↗
PubMed1988

Fetal echocardiography. VIII. Aortic root dilatation--a marker for tetralogy of Fallot.

Tetralogy of Fallot has increased in incidence during the past decade. Although abnormalities of the four-chamber screening examination of the fetal heart identifies structural anomalies associated with semilunar and atrioventricular valve hypoplasias, the anomalies associated with tetralogy of Fallot are not as readily identifiable from the four-chamber view alone. This study was designed to determine whether aortic root dilatation, commonly observed in the newborn with tetralogy of Fallot, is a marker for tetralogy of Fallot diagnosed in utero. In 45 normal (control) fetuses the biparietal diameter, head circumference, abdominal circumference, and femur length were measured and M-mode measurements were made of the biventricular outer dimension and aortic root dimension. The aortic root dimension from seven fetuses (18, 19, 20, 23, 32, 33, and 34 weeks' gestation) with tetralogy of Fallot was increased in dimension when compared with cardiac (biventricular outer dimension) and noncardiac biparietal diameter, head and abdomen circumferences, and femur length parameters. In conclusion, incorporation of aortic root imaging with the four-chamber view of the fetal heart during a routine screening examination allows for identification of fetuses with tetralogy of Fallot.

Adult↗
PubMed1988

Reverse end-diastolic flow velocity on umbilical artery velocimetry in high-risk pregnancies: an ominous finding with adverse pregnancy outcome.

Systolic/diastolic ratios of umbilical velocimetry have been used to assess downstream placental vascular resistance. Reverse end-diastolic flow velocity during end diastole suggests extreme abnormality in waveform and resistance. We reviewed our experience of patients showing reverse end-diastolic flow velocity over a 2 1/2-year period. Out of 550 high-risk patients studied with umbilical velocimetry over this period, 12 patients showed the finding. All patients were delivered of small for gestational age fetuses and the perinatal mortality in this group was 50%. There was also significant perinatal morbidity as judged by cesarean section performed because of fetal distress, low Apgar scores, days in neonatal intensive care, prematurity, placental infarcts, and lethal anomalies. These findings suggest that reverse end-diastolic velocity on umbilical velocimetry is associated with catastrophic perinatal outcome, and aggressive perinatal management may be advised in this group of patients.

Abnormalities, Multiple↗
PubMed1988

The use of transvaginal sonography for evaluation of postmenopausal ovarian size and morphology.

Ultrasonic evaluation has been suggested as a possible screening tool for early changes in ovarian morphology. This study uses transvaginal sonography to evaluate the ovaries in postmenopausal women who were scheduled for gynecologic surgery unrelated to adnexal disease. The findings of ultrasonic ovarian examination are compared with the findings at surgery and the pathologic evaluation of the ovaries. Nine (17.3%) abnormal ovaries were identified by ultrasonography and at surgery and were confirmed at pathologic examination. Among the abnormal ovaries there were one malignancy (10%) and two neoplasms with known malignant potential (20%). One ovary that was identified to have microscopic areas of Brenner tumor cells at pathologic examination was described as normal by both ultrasound and surgical evaluation. The sensitivity (90%) and specificity (100%) of vaginal sonography were the same as that of gross examination of the ovary at the time of surgery. We conclude that vaginal sonography is a reliable tool in the detection of early abnormalities in the postmenopausal ovary.

Aged↗
PubMed1988

Maternal and fetal blood flow velocity waveforms in patients with preterm labor: prediction of successful tocolysis.

Umbilical and uterine artery velocimetry was performed using continuous-wave Doppler ultrasound (Angioscan III) in 60 patients in preterm labor. Peak-systolic/end-diastolic ratios were calculated according to previously described techniques. All measurements were made before tocolytic therapy was begun: magnesium sulfate (n = 40) or ritodrine (n = 20). The mean gestational age was 33.1 +/- 1.5 weeks (range 29 to 36 weeks). Twelve (20%) patients had elevated (greater than 2.6) pretherapy uterine peak-systolic/end-diastolic ratios, 10 (16.7%) patients had elevated (greater than 3.5) pretherapy umbilical peak-systolic/end-diastolic ratios, and in eight (13.3%) patients both ratios were elevated. In seven (58.4%) of the 12 patients with elevated uterine peak-systolic/end-diastolic ratios, six (60%) of the 10 patients with elevated umbilical peak-systolic/end-diastolic ratios, and five (62.5%) of the eight patients with both ratios elevated tocolytics failed and the women were delivered within 48 hours, compared with seven (14.6%) of 48, eight (16%) of 50, and six (13.0%) of 46 with normal ratios, respectively (p less than 0.05). We conclude that patients in preterm labor with elevated pretherapy uterine and/or umbilical peak-systolic/end-diastolic ratios are more likely to fail tocolysis therapy and be delivered preterm than those with normal ratios. It may therefore be useful to include umbilical and uterine velocimetry in the initial evaluation of preterm labor.

Adult↗