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Biomedical subjects

L D Platt

Publications and source records attributed to L D Platt.

At least 55 records · Page 3Linked to original sources
PubMed1995

Tumor marker trends in asymptomatic women at risk for ovarian cancer: relevance for ovarian cancer screening.

The purpose of our study was to examine single and serial determinations of five biomarkers in asymptomatic women at risk for epithelial ovarian cancer to define median values and trends in a cancer-free cohort. Women were enrolled in the Gilda Radner Ovarian Cancer Detection program at Cedars-Sinai Medical Center, Los Angeles, California from July 1, 1991, to July 1, 1993. Biomarkers studied include CA-125, LASA, DM-70K, UGP, and HER-2. Biomarker values that were analyzed included those obtained on the first patient visit and in a subset of values evaluated at 6-month follow-ups. A total of 590 women were included in the study; 425 were premenopausal and 165 were postmenopausal. No one in this study group has developed ovarian cancer within a 12-month follow-up period. Postmenopausal women had significantly lower values for CA-125 (12 vs 19 U/ml, P = 0.0001) and higher values of LASA (16.6 vs 15.4 mg/dl, P = 0.0001), DM/70K (11 vs 0 U/ml, P < 0.001), UGP (3.3 vs 0.3 U/ml, P < 0.001), and HER-2 (12 vs 11 U/ml, P = 0.009) than premenopausal women. Less than 5% of the women had elevated tumor marker values on both screens except for CA-125, where 15% of women studied had two consecutive visits with elevated values (> 35 U/ml). Two women demonstrated an exponential rise in CA-125 between visits. Premenopausal women differ in median biomarker values compared to postmenopausal women. Elevations in single tumor markers, combinations of markers, and exponential increases of markers have all produced false-positive results for ovarian cancer within the 12-month follow-up period. Exponential increases produced the smallest false positive rate (n = 2), but further study and follow-up are needed to determine the efficacy of these tests in ovarian cancer screening.

Adult↗
PubMed1995

Using ICD-9 codes to identify indications for primary and repeat cesarean sections: agreement with clinical records.

Aggregate databases are increasingly being used to evaluate appropriateness of care, and, for cesarean sections, Anderson and Lomas' International Classification of Diseases, 9th Revision (ICD-9), coding hierarchy is a widely used tool. The aim of this study was to assess the validity of the hierarchy and expand its applicability to repeat cesareans. Hospital records of 1885 singleton cesareans were reviewed. Clinical indications and ICD-9 hierarchical codes were concordant for 83% of primary and 86% of repeat cesareans; modification allowed elective repeat cesareans to be distinguished from indicated procedures. The Anderson and Lomas ICD-9 hierarchy is a valid tool for assessing indications for cesarean. The current modification improves its clinical utility and expands its application to repeat procedures.

Breech Presentation↗
PubMed1994

Trisomy 8 mosaicism in chorionic villus sampling: case report and counselling issues.

We report an unusual case involving chorionic villus sampling (CVS) and trisomy 8 mosaicism. CVS showed a normal direct preparation while the culture showed mosaicism for trisomy 8. Subsequent amniocentesis revealed only normal chromosomes. A peripheral blood culture after birth revealed low-level trisomy 8 mosaicism. The patient appeared phenotypically and developmentally normal at 30 months of age. We conclude that prenatal counselling for similar cases needs to include the rare but real possibility that chromosome mosaicism detected prenatally may be found postnatally with largely unknown consequences. Secondly, low-level chromosomal mosaicism may be more common than previously recognized. Thirdly, very low-level trisomy 8 mosaicism may be compatible with a normal phenotype but long-term follow-up is required. And lastly, the use of fetal blood sampling is questionable in these cases because the phenotype may not be accurately predicted. Further studies of such cases are needed to address these important and unanswered issues, including the potential implication of mosaicism on academic performance and cognitive functioning.

Adult↗
PubMed1994

The current status of ultrasound and color Doppler imaging in screening for ovarian cancer.

The lack of significant improvement in ovarian cancer survival in over 3 decades has focused interest on early disease detection as well as the development of more effective therapies. Ultrasound's ability to discern alterations in ovarian architecture and color doppler's ability to recognize malignancy-associated angiogenesis have resulted in the application of these techniques to ovarian cancer screening. Morphology scoring systems have been developed to quantitate the anatomic alterations seen on ultrasound. Prospective ovarian cancer ultrasound screening trials involving 11,283 women were evaluated: 486 participants underwent surgical exploration and 19 ovarian cancers were diagnosed. Thirteen cases were stage I where the impact of screening on disease survival is thought to be maximal; 5/13 were invasive epithelial malignancies, 7/13 were borderline tumors, and 1/13 was a granulosa cell tumor. Overall, 32 surgeries (95% CI = 20-58) were required to diagnose one stage I ovarian cancer; if only those women with a family history of ovarian cancer are included in the analysis, then 17 surgeries (95% CI = 14-41) would be required. Potential clinical implications of these results are discussed, as well as future directions for screening.

Adolescent↗
PubMed1994

Introduction of laparoscopically assisted vaginal hysterectomy in a private teaching community hospital.

STUDY OBJECTIVE: To compare laparoscopically assisted vaginal hysterectomy (LAVH) with traditional total abdominal hysterectomy (TAH) when the laparoscopic approach is introduced into a private hospital. DESIGN: During 1 year, 49 LAVHs were performed and compared with 51 consecutive TAHs using retrospective chart review and statistical analysis. SETTING: A private, university-affiliated, teaching hospital. PATIENTS: All patients undergoing LAVH, and the first 51 TAHs performed during the study year. MEASUREMENTS AND MAIN RESULTS: No major complications occurred in either group. Significant differences were observed in uterine weight (161 +/- 92 g vs 331 +/- 354 g), operating time (164 +/- 48 min vs 108 +/- 28 min), and hospital stay (2.93 +/- 1.21 days vs 4.00 +/- 1.54 days) for LAVH and TAH, respectively. Hospital charges for LAVH average $4074 more than for TAH, primarily due to the use of disposable laparoscopic equipment. CONCLUSIONS: Laparoscopically assisted vaginal hysterectomy may be performed safely in a private community hospital with appropriate surgeon credentialing and training. Modifying techniques to minimize the use of disposable equipment would make the procedure more cost effective.

Adult↗
PubMed1994

Prospective multicenter study of second-trimester nuchal skinfold thickness in unaffected and Down syndrome pregnancies.

OBJECTIVE: To determine the distribution of nuchal skinfold thickness in normal and Down syndrome pregnancies and to evaluate the use of this sonographic measurement as a screening test for fetal Down syndrome. METHODS: A prospective, multicenter, population-based study was performed by experienced obstetric sonographers on 1382 women with sonographically normal fetuses undergoing second-trimester amniocentesis for the indication of advanced maternal age. A standard, well-defined sonographic image was obtained at all collaborating centers. The distributions of nuchal skinfold thickness were compared between euploid and Down syndrome fetuses. RESULTS: There were 1346 chromosomally normal pregnancies, 13 fetuses with Down syndrome (1:106), and 23 other chromosome abnormalities. Seventeen fetuses had measurements of 6 mm or greater, and one of these had Down syndrome. The median nuchal skinfold thickness in Down syndrome was 3.2 mm and in euploid fetuses was 3.1 mm. By the Mann-Whitney rank-sum test, there was no statistically significant difference in nuchal skinfold between the euploid and Down syndrome fetuses (P = .5). Overall, using a nuchal skinfold thickness of 6 mm or greater as a screening test, the detection rate for Down syndrome was one of 13 (8%), the false-positive rate was 16 of 1382 (1.2%), the positive predictive value was one of 17 (6%), and the probability of detecting Down syndrome was 6.5%. CONCLUSION: In this investigation, excess nuchal skinfold thickness was a poor and unreliable screening test for Down syndrome.

Adult↗
PubMed1994

Repeat cesareans: how many are elective?

OBJECTIVE: To describe the clinical indications for repeat cesarean delivery and to compare these with indications for primary procedures. METHODS: We reviewed cesarean deliveries at our academic nonprofit hospital during 1992 (n = 1885). The indication for the procedure was abstracted based on surgeon operative reports and discharge ICD-9 codes (International Classification of Diseases, Clinical Modification, 9th Edition). RESULTS: The hospital cesarean rate was 28.7%; 34% of these were repeat procedures (n = 643). Elective cesarean delivery was the leading cause of repeat cesareans, followed by "other" indications, dystocia, breech, and fetal distress. In contrast, dystocia was the leading cause for primary cesarean, followed by fetal distress, "other," and breech presentation. One hundred women (15.6%) undergoing repeat cesarean had absolute or relative contraindications to a trial of labor. CONCLUSIONS: Indications for cesareans using hierarchies based on ICD-9 codes do not attempt to differentiate categories of indications for repeat cesarean. Current recommendations for lowering cesarean rates by increasing vaginal birth after previous cesarean are based on aggregate data and do not recognize that some repeat cesareans are clinically indicated. A coding system designed to distinguish elective from indicated repeat cesareans would be useful for future prospective studies.

Adult↗
PubMed1993

Preaxial ray reduction defects as part of valproic acid embryofetopathy.

It is well known that prenatal exposure of valproic acid (VPA) may be associated with the occurrence of neural tube defects (Robert and Gibaud, 1982). Additional adverse effects related to VPA exposure include craniofacial abnormalities, skeletal defects, brain defects, cardiovascular defects, and urogenital defects (DiLiberti et al., 1984; Winter et al., 1987; Huot et al., 1987; Jager-Roman et al., 1986; Martinez-Frias, 1990). Recently, radial ray reduction has been reported as a severe type of skeletal defect associated with VPA exposure (Jager-Roman et al., 1986; Huot et al., 1987; Verloes et al., 1990). We report two additional cases of this severe limb reduction defect as part of a broader pattern of altered morphogenesis in fetuses exposed to VPA and to confirm an association between such severe specific skeletal defects and VPA exposure. We briefly review teratologic studies in experimental animals which document the biologic plausibility of this association, and suggest that fetuses exposed to VPA undergo detailed prenatal ultrasonographic evaluation of the limbs.

Abnormalities, Drug-Induced↗
PubMed1993

Fetal akinesia/hypokinesia sequence: prenatal diagnosis and intra-familial variability.

Intrauterine fetal movement plays a key role in normal embryonic and fetal development (Moessinger, 1983). When movement is absent or decreased, abnormal development takes place which can be appreciated in newborns and/or fetuses with the fetal akinesia/hypokinesia sequence. This sequence is caused by a number of heterogeneous entities which result in decreased fetal movements by the action of intrinsic or extrinsic factors. Prenatal diagnosis of the akinesia/hypokinesia sequence may be possible during the second trimester through the use of real-time ultrasonographic evaluation of fetal movement. We report a family with three consecutive affected pregnancies in which the prenatal presentation of this sequence varied. Based on the phenotypic findings of the three affected fetuses, we believe that although they superficially resemble those features found in the New-Laxova syndrome, they are probably affected with a distinctly different lethal form of akinesia/hypokinesia transmitted in an autosomal recessive fashion.

Abnormalities, Multiple↗
PubMed1993

Cook obstetrics and gynecology catheter multicenter chorionic villus sampling trial: comparison of birth defects with expected rates.

OBJECTIVE: The null hypothesis was that offspring of women undergoing first-trimester chorionic villus sampling do not experience a rate of birth defects exceeding background rates. STUDY DESIGN: Follow-up information regarding major malformations was prospectively sought on offspring of 4105 women undergoing first-trimester chorionic villus sampling from nine centers participating in a collaborative study with the Cook obstetrics and gynecology catheter. These data were compared with data from the Collaborative Perinatal Project and other registries. RESULTS: A total of 84 offspring with major malformations was identified (2.36%). Compared with background rates, there was no increase in the incidence of total malformations or specific malformations (including limb reduction defects) in the subjects. One institution experienced all three limb reduction defects in this series; the probability of this occurring by chance alone is < 1%. CONCLUSION: Chorionic villus sampling was not found to result in an increase in major birth defects or in specific categories of birth defects in this series.

Catheterization↗
PubMed1993

Effect of pregnancy on the vasodepressor response to atrial natriuretic factor.

OBJECTIVE: We attempted to determine whether pregnancy alters the vasodepressor response to both physiologic and pharmacologic infusions of atrial natriuretic factor 99-126. STUDY DESIGN: Ten virgin and 10 pregnant (17 +/- 1 days of gestation) conscious, unrestrained Sprague-Dawley rats with chronic indwelling vascular catheters were studied. Mean arterial pressure and heart rate were measured in response to steady-state infusions of either saline solution or increasing concentrations of atrial natriuretic factor (range 5 to 2560 ng.kg-1.min-1). RESULTS: Basal mean arterial pressure was significantly lower in pregnant rats than in virgin rats (89 +/- 3 vs 97 +/- 2 mm Hg, p < 0.02). Atrial natriuretic factor induced significant dose-dependent decreases in mean arterial pressure and heart rate in virgin and pregnant rats (p < 0.001). The hypotensive effects of atrial natriuretic factor were blunted in the pregnant rats only in response to the highest concentrations of atrial natriuretic factor administered (-27 +/- 3 mm Hg in pregnant rats vs -43 +/- 3 mm Hg in virgin rats, p < 0.005). CONCLUSIONS: The vasodepressor response to physiologic infusions of atrial natriuretic factor was not affected by pregnancy status. However, pharmacologic infusions of atrial natriuretic factor resulted in a blunted vasodepressor response in the pregnant animals. This may be due to alterations in vascular atrial natriuretic factor receptors, changes in the clearance rate of atrial natriuretic factor, or the modulating effects of other vasoactive hormones.

Animals↗
PubMed1993

Fetal echocardiography: factors that influence imaging of the fetal heart during the second trimester of pregnancy.

OBJECTIVE: The four-chamber view of the heart is an important component of the ultrasonographic examination of the fetus. However, during the second trimester of pregnancy the fetal heart cannot always be imaged in every patient. The purpose of this study was to ascertain the rate of successful imaging of the fetal heart during the second trimester and to determine factors that may influence imaging. METHODS: Seven hundred and nine second trimester fetuses were examined and an attempt was made to obtain the four-chamber and outflow tract views of the heart. Analysis included multiple logistic regression models of the main effects and interactions of ten candidate variables. RESULTS: The four chambers and outflow tracts were imaged in 643 fetuses (90.7%) and not imaged in 66 (9.3%). Fifty-two of 709 patients (7.3%) had had previous surgery. In the 52 patients with a history of previous surgery, the heart could not be imaged in 18 (34%). Six hundred and fifty-seven patients (92.7%) did not have previous surgery. Of this group, the fetal heart could not be imaged in 48 (7.3%). In only one fetus in which the heart could not be imaged was it because of fetal position. Three independent risk factors that influenced imaging of the fetal heart were gestational age, maternal adipose tissue thickness, and previous lower abdominal surgery. Increasing gestational age increased the probability of imaging the heart, whereas increasing adipose tissue thickness and a history of previous surgery decreased the probability of imaging the heart. COMMENTS: When the fetal heart cannot be imaged during the second trimester, these factors should be identified. Using data from this study, the gestational age at which the highest probability of imaging the heart can be determined if the thickness of the adipose tissue and a history of lower abdominal surgery are known.

Abdomen↗
PubMed1993

Determinants of utilization of Tay-Sachs screening.

OBJECTIVE: To identify the characteristics of patients associated with optimal utilization of Tay-Sachs screening. METHODS: Medical records of patients undergoing amniocentesis for genetic diagnosis were reviewed. Three hundred twenty-nine of 537 charts evaluated were from individuals at risk for Tay-Sachs heterozygosity. Among these, 213 couples had previously been screened for Tay-Sachs. In 116 couples, neither member of the couple had been screened before amniocentesis. A concurrent reference group consisted of 208 couples without an indication for Tay-Sachs screening. Patient characteristics, including ethnicity, genetic screening history, parental ages, and pregnancy history, were reviewed for each group. Analysis of variance and likelihood chi 2 test were used for statistical analysis. RESULTS: There were no significant differences in maternal age or reproductive history among the groups. The most common indication for amniocentesis was advanced maternal age for all three groups. However, the previously screened group was more than twice as likely to self-refer because of a positive family history or patient anxiety than was the unscreened group (P = .006). Conversely, the unscreened group was more than twice as likely as screened couples to be referred because of a positive high or positive low maternal serum alpha-fetoprotein level (P = .002). CONCLUSION: Despite 2 decades of professional and lay education, many couples are unaware of their individual risk for Tay-Sachs heterozygosity. Additional education, most likely at the professional level, is needed to maximize informed participation.

Fathers↗