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I Blickstein

Publications and source records attributed to I Blickstein.

At least 19 recordsLinked to original sources
PubMed1999

The relation between inter-twin birth weight discordance and total twin birth weight.

OBJECTIVE: We tested the hypothesis that the frequency of growth discordance among twins is not related to the uterine capacity for carrying twins. METHOD: We counted and compared the frequencies of birth weight discordance of more than 25% in an unlike-sexed twin cohort (n = 1244) and in a population-based twin cohort (n = 7570) across the deciles of the total twin birth weight (twin A + twin B) distribution. The birth order of the heavier twin was noted. RESULTS: Similar frequencies of discordant pairs were found in both cohorts (11% and 12%, respectively; Mantel-Haenszel chi2 test: P = .131, odds ratio (OR) 0.9, 99% confidence interval (CI) 0.67, 1.11; Woolf test for heterogeneity: two-tailed P = .472). In the discordant pairs, twin A was considerably more often the heavier twin in all birth weight deciles (unlike-sexed cohort: P < 10(-8), OR 5.9, 99% CI 3.0, 11.7; population-based cohort: P < 10(-8), OR 3.1, 99% CI 2.3, 4.0), and in both cohorts (inter-cohort difference: P = .109, OR 1.4, 99% CI 0.83, 2.32). Both cohorts showed a similar nonlinear trend: given that X = decile order, discordance decreased as a function of 22.0 - 6.54 ln[X] for the unlike-sexed twins cohort and 23.0 - 8.18 ln[X] for the population-based cohort, with r values of 0.967. CONCLUSION: The more favorable the uterine milieu for carrying twins, the smaller the likelihood of discordant twin growth. Birth order of the heavier twin appears to be an integral part of the discordance phenomenon. The similarity of the cohorts suggests that these conclusions are valid for both like and unlike-sexed twins.

Birth Weight↗
PubMed1998

Biblical twins.

Explore the source record for details and available documents.

Bible↗
PubMed1998

Antepartum risks of shoulder dystocia and brachial plexus injury for infants weighing 4,200 g or more.

A cohort of 236 vaginally delivered neonates weighing > or = 4,200 g was evaluated. Shoulder dystocia was encountered in 27 deliveries (11.4%) and brachial plexus injury was diagnosed in 3 infants (1.3%). The 'traditional' antepartum risk factors could not be associated with shoulder dystocia. In this cohort, primiparity was significantly more frequent among the dystocia cases (OR = 8.58, 99% CI = 1.35-54.35, p = 0.021). Shoulder dystocia could not be attributed to a particular difference between the current and the previous heaviest birth weight. A policy of cesarean section for all infants weighing > or = 4,200 g would result in at least 5- to 6-fold increase in cesarean rate in this group of patients. Our data reconfirm that shoulder dystocia and brachial plexus injury are unpredictable, even in macrosomic infants. It is a matter of policy whether to accept the expected 1:9 and 1:79 respective risks associated with vaginal births.

Adult↗
PubMed1997

Quantitative assessment of gray-level perception: observers' accuracy is dependent on density differences.

Sonographic image density represents tissue echogenicity, or the acoustic nature of scanned tissue. It has the potential to distinguish normal from abnormal tissue. Humans are poor assessors of tissue echogenicity, yet their abilities have not been quantitatively compared to more objective methods. We compared the accuracy of image density differentiation by the human eye and by densitometry in the fetal liver model. A group of 60 observers was asked to compare the echogenicity of three pairs of images of a fetal liver. Twenty-three repeated the comparison several weeks later. Image density was measured by electro-optical densitometry. The two-tailed signed rank test was used to compare the observer's perceptions with the density values and the repeated observations with the original responses. The density of each fetal liver image in pair A was the same. Image B1 had a 12.3% lower density than image B2, and image C1 had a 6.3% greater density than image C2. Observers were accurate more often when comparing images with large density differences (pair B) than they were when comparing images with the same density (pair A) or with small density differences (pair C). Accuracy was not related to being medically qualified or from an obstetric or gynecological department. Intraobserver variation was not significant. We conclude that the human eye is extremely inaccurate at discerning differences in echogenicity when images have small or no differences in optical density. Densitometry is, therefore, indispensable for accurate image density assessment.

Densitometry↗
PubMed1997

Computed sonography: requiem to echogenicity assessment?

We studied the influence of changes in gain settings, log compression, persistence, preprocessing, and postprocessing on image density in the fetal liver model. Each parameter was studied while the others were held constant. The image density was objectively measured by electrooptical transmission densitometry using a transparent film output. Neither the persistence nor the preprocessing levels significantly changed image density. Postprocessing of sonographic images produced significant differences (p < 0.02) in mean image density of most of the various postprocessing curves and is a serious confounder of tissue echogenicity assessment. The data reconfirmed that there is a linear relationship (r = -0.94 to -0.997) between image density and gain setting. However, each log compression setting significantly changed (p < 0.0000001) this relationship, obviating possible image density calibration. Our data suggest that manipulation of image parameters by computed sonographic technology obviates accurate echogenicity assessment.

Densitometry↗
PubMed1997

Maternal mortality in twin gestations.

OBJECTIVE: To review various aspects of maternal morbidity and delivery complications leading to maternal death in twin gestations. STUDY DESIGN: Literature research. RESULTS: The incidence of maternal mortality associated with twin gestation is not known but can be estimated from a few community-based series and from studies on maternal morbidity related to twins. The combination of physiologic changes and perinatal pathologies that are either unique or more common in twin gestations (e.g., preeclampsia/eclampsia, need for tocolysis, anemia, abruption placentae, special delivery circumstances and cesarean section) is certainly increasing the maternal risk for serious morbidity and even mortality. CONCLUSION: Twin pregnancies should be included among the categories of pregnancy-related maternal death in order to learn how to eliminate avoidable mortality in twin gestations.

Abruptio Placentae↗
PubMed1996

Post-traumatic vulvar endometriosis.

We report a case of vulvar endometriosis presenting as a vulvar mass following trauma in a 12 years old, 3 months post-menarcheal girl. The presumptive etiology is the direct implantation of endometrial cells. Painful swelling of the vulvar mass appeared gradually during menses. Excision of suspected vulvar endometriosis is suggested as the definite treatment.

Child↗
PubMed1996

Is intertwin birth weight discordance predictable?

OBJECTIVE: To compare the efficacies of intertwin difference in abdominal circumferences (ACs) and estimated fetal weight (EFWs) to predict birth weight discordance in twin gestations. METHODS: Ninety pairs of twins with sonographic measurements of AC and femur length, performed within 2 weeks before delivery, were included in the study. The EFW was calculated (Hadlock's formula). We used Bayes' theorem and the Mantel-Haenszel chi 2 test to calculate and compare the rates of false-positive and false-negative prediction of the cutoff values of 15, 20, and 25% intertwin birth weight discordance by the intertwin EFW difference and an intertwin AC difference of > or = 18 mm. RESULTS: There were no significant difference between the two methods to predict birth weight discordance at 15-25% discordance (p = 0.254, OR = 0.33, 95% CI = 1.45-0.24) and at > 25% discordance (p = 0.112, OR 0.18, 95% CI = 0.03-1.34). CONCLUSIONS: Both the intertwin AC difference (> or = 18 mm) and intertwin EFW difference have similar negative predictive values and the same efficacy to exclude discordant growth. Because of the relatively low positive predictive values, birth weight discordance cannot be accurately predicted by either method.

Bayes Theorem↗
PubMed1996

Hyperestrogenemia and presence of estrogen receptors associated with an epithelial ovarian tumor of low malignant potential.

An 80-year-old woman presented with breast congestion, tenderness and pain. Mammography was normal. Circulating estradiol was markedly elevated, while LH and FSH were low. Pelvic examination and imaging revealed an ovarian mass which was extirpated during total abdominal hysterectomy and bilateral salpingo-oophorectomy. Histopathology revealed an ovarian mucinous cystadenocarcinoma of low malignant potential, stage 1. The tumor was positively stained for estrogen receptors. Estradiol levels returned to normal post-operatively, with a corresponding adjustment of LH/FSH. Possible autocrine steroid production is discussed.

Aged↗
PubMed1995

The intrauterine ponderal index in relation to birth weight discordance in twin gestations.

OBJECTIVE: To establish the relationship between the fetal ponderal index and birth weight discordance in twins. METHOD: The fetal ponderal index (estimated fetal weight divided by femur length3) was calculated in 86 pairs of twins delivered within 2 weeks of the last sonography and analyzed in relation to birth weight discordance. RESULTS: A weak but significant correlation between fetal ponderal index and birth weight (r = 0.26, P < 0.0007) but no correlation with gestational age (r = 0.035, P = 0.65) were found. Members of concordant pairs (< 15% birth weight difference) had a significantly higher fetal ponderal index compared with members of mildly (15-25%) discordant pairs (P < 0.02), but not as compared with members of severely discordant (> 25%) pairs. CONCLUSION: The characteristics of the fetal ponderal index in twins are similar to those in singletons. Fetal size seems to be diminished in severe but not in mild discordants. However, in its present form, the fetal ponderal index is a poor predictor of discordant growth and therefore should be employed cautiously in twin gestations.

Birth Weight↗
PubMed1995

Menopause is associated with a significant increase in blood monocyte number and a relative decrease in the expression of estrogen receptors in human peripheral monocytes.

PROBLEM: The clinical significance of the differential expression of estrogen receptor (ER) in human monocytes was evaluated. METHOD: Two color flow cytometry analysis was used on peripheral blood samples of young and postmenopausal females and postmenopausal females treated with estrogen replacement therapy. In addition, the monocyte and lymphocyte counts and the blood estrogen levels of each patient were determine. RESULTS: During menopause there is a significant decrease in the percentage of ER positive monocytes, and an increase in blood monocyte number, which declines following estrogen replacement therapy to values of the young. CONCLUSIONS: These findings suggest that estrogen modulates the monocyte numbers and its effects may be mediated through the ER in the monocytes.

Adolescent↗
PubMed1995

Can placental surface area and neonatal weight be predicted from placental surface measurements? Preliminary observations on normal-term pregnancies.

OBJECTIVE: To evaluate the relations between chorionic plate measurements and neonatal weight as prerequisites for possible prediction of fetal weight using antenatal placental measurements. METHODS: We examined freshly delivered placentas. The surface area (chorionic plate) was measured using millimeter paper, and the two longest diameters (at right angles to each other) were determined (L1 and L2). The mean longest diameter [Lm = (L1 + L2)/2] was calculated. The relation of these diameters to neonatal and placental weight was studied. RESULTS: We examined 57 randomly selected placentas after normal pregnancy and delivery. The three chorionic plate diameters significantly correlated with the surface area and the placental and neonatal weights. The strongest correlation (r = 0.94; p < 10(-6) was found between Lm and placental surface area. CONCLUSIONS: Our preliminary results suggest that chorionic plate measurements may be suitable to predict placental surface area and neonatal birth weight in normal-term pregnancies. Further studies to verify prospectively these relations at various gestational ages and in cases of abnormal fetal growth are required.

Birth Weight↗