A high-sensitivity alternative to "routine" genetic amniocentesis: multiple urinary analytes, nuchal thickness, and age

OBJECTIVE

Our purpose was to evaluate the Down syndrome screening efficiency of a new algorithm consisting of multiple urinary biochemical and ultrasound markers for use in high-risk groups such as women of advanced maternal age.

STUDY DESIGN

The urinary beta-core fragment of human chorionic gonadotropin (beta-core fragment) and total urinary estriol, along with fetal nuchal thickness, were measured prospectively in pregnant women who were undergoing genetic amniocentesis at midtrimester (15 to 24 weeks). The most common indication for amniocentesis was advanced maternal age (90.2%). An analyte ratio (beta-core fragment/total estriol ratio) was developed. The values were expressed as multiples of the normal median. An increase in the observed nuchal thickness (delta nuchal thickness) above that expected on the basis of the biparietal diameter was calculated. On the basis of the mean and standard deviations of the urinary analyte ratio in normal fetuses and also Down syndrome, we calculated individual Down syndrome likelihood ratios for each of the two parameters, using gaussian analysis. The product of the likelihood ratios, based on delta nuchal thickness and urinary beta-core fragment-total estriol values times the maternal age-related risk, gave the overall Down syndrome risk. The screening efficiency of our algorithm at various risk thresholds was determined.

RESULTS

There were 13 (2.8%) cases of Down syndrome in a total study population of 457. At a risk threshold of >1 in 70, the sensitivity was 92.3% for a false-positive rate of 4.5%. Corresponding values at a risk threshold of >1 in 78 were a sensitivity of 100% with a false-positive rate of 5.2%.

CONCLUSION

By combining urinary analyte, nuchal thickness, and maternal age data, we achieved a high Down syndrome detection rate with a low false-positive rate. This algorithm would be attractive as an alternative to "routine" amniocentesis based solely on advanced maternal age. The potential benefits of this protocol could include a significant reduction in the rate of amniocentesis, along with substantial savings in medical expenditures.

Renal tubular dysgenesis, absent nipples, and multiple malformations in three brothers: a new, lethal syndrome

We report on three brothers with renal tubular dysgenesis and absent nipples, each also had other malformations including pre-auricular pits and a preauricular tag, branchial clefts, choanal atresia, pulmonary lobation anomaly, ventricular septal defect, type IIB interrupted aortic arch, absent gallbladder, absent thymus, parathyroid gland, accessory spleen, imperforate anus, clinodactyly, and broad digits and small nails. All three infants died neonatally. This pattern of clinical malformations appears to be a previously unreported syndrome.

In situ measurements of organics, meteoritic material, mercury, and other elements in aerosols at 5 to 19 kilometers

In situ measurements of the chemical composition of individual aerosol particles at altitudes between 5 and 19 kilometers reveal that upper tropospheric aerosols often contained more organic material than sulfate. Although stratospheric aerosols primarily consisted of sulfuric acid and water, many also contained meteoritic material. Just above the tropopause, small amounts of mercury were found in over half of the aerosol particles that were analyzed. Overall, there was tremendous variety in aerosol composition. One measure of this diversity is that at least 45 elements were detected in aerosol particles. These results have wide implications for the complexity of aerosol sources and chemistry. They also offer possibilities for understanding the transport of atmospheric aerosols.

Hyperglycosylated hCG, a potential alternative to hCG in Down syndrome screening

Hyperglycosylated hCG (H-hCG) is a minor variant of hCG with abnormal oligosaccharide side chains. It is the principal gonadotropin detected in the serum and urine of patients with gestational choriocarcinoma. A monoclonal antibody was produced against this antigen and an immunoassay developed. Levels of hCG and H-hCG were determined in 142 urine samples from normal pregnancies from 10 to 21 weeks of gestation. Levels were normalized to urine creatinine concentration, and were each plotted against gestational age. Bi-weekly median values were calculated, the best-fitting regression lines were determined, and multiples of the normal median (MoM) were computed. 10 Down syndrome pregnancy samples were tested from 11 to 21 weeks of gestation. The median hCG and H-hCG levels in the Down syndrome cases were 1.9 MoM and 5.7 MoM of unaffected cases, respectively. Four of 10 hCG measurements and 9 of 10 H-hCG determinations exceeded the 95th centile of unaffected cases. H-hCG identified 90 per cent of Down syndrome cases with a 5 per cent false-positive rate. This is more than twice the number of cases detected by an hCG assay. H-hCG may be an effective replacement for hCG in antenatal Down syndrome screening. This is a preliminary report consisting of only 152 samples. Further studies are needed now to verify the Down syndrome screening utility of this potentially valuable new marker.

An alternative for women initially declining genetic amniocentesis: individual Down syndrome odds on the basis of maternal age and multiple ultrasonographic markers

OBJECTIVE

Our purpose was to develop a method of calculating the individual odds of Down syndrome on the basis of a combination of maternal age and multiple ultrasonographic parameters that can be used to counsel women at high risk who initially decline amniocentesis.

STUDY DESIGN

Maternal age and ultrasonographic biometry data were collected prospectively on 3254 normal and 30 Down syndrome singleton fetuses between 15 and 24 weeks' gestation. Humerus length data were expressed as multiples of the normal median. Log transformation of the humerus length data permitted their expression in gaussian frequency distributions and the calculation of likelihood ratios for Down syndrome on the basis of humerus length. We also developed likelihood ratios on the basis of the degree of nuchal skinfold thickening and the presence or absence of hyperechoic fetal bowel and hypoplastic fifth digit.

RESULTS

The ultrasonographic parameters and maternal age did not significantly correlate with each other and were significant independent predictors of Down syndrome. We therefore calculated the individual odds of Down syndrome by using the product of the age-related risk and the likelihood ratios associated with nuchal thickening, humerus length shortening, and the presence or absence of hyperechoic fetal bowel or fifth digit hypoplasia, respectively. At a Down syndrome risk level of >1:50, a 60.0% detection rate with 4.5% false-positive rate was observed with a screen-positive rate of 5.5%, positive predictive value of 1:10, and odds ratio (95% confidence interval) of 28.4 (12.8 to 64.0).

CONCLUSION

This is the first report of individual odds calculation based on multiple midtrimester biometry parameters and maternal age. The screening efficiency is similar to that reported with triple-analyte serum screening. These data are useful for counseling women who are at increased Down syndrome risk and initially decline amniocentesis.

Prenatal confirmation of true fetal trisomy 22 mosaicism by fetal skin biopsy following normal fetal blood sampling

Trisomy 22 mosaicism diagnosed at 20 weeks' gestation by amniocentesis in a 35-year-old woman was not confirmed by fetal blood sampling. Subsequent fetal skin biopsy revealed trisomy 22 in 7 of the 15 fibroblasts analysed. We conclude that, depending on the chromosome involved, fetal skin biopsy should be considered in the diagnostic work-up when mosaicism is found in amniotic fluid.

A new screening protocol combining urine beta-core fragment and ultrasonography for Down syndrome detection

OBJECTIVE

Our purpose was to ascertain the screening efficiency of a new midtrimester Down syndrome detection protocol that combines maternal urine testing and ultrasonographic examination.

STUDY DESIGN

In a prospective study, beta-core fragment, the stable end product of human chorionic gonadotropin metabolism, was measured in maternal urine. The results were standardized for urine creatinine levels. The study was performed in women undergoing midtrimester genetic amniocentesis (15 to 24 weeks' gestation). Urine beta-core fragment values were expressed as multiples of the normal median for gestational age. The screening performance of a combination of ultrasonographic parameters and urine beta-core values for Down syndrome detection was determined.

RESULTS

A total of 511 singleton pregnancies in women undergoing amniocentesis were studied, 18 of the women (3.5%) had a Down syndrome fetus. A urine beta-core fragment level > or = 97th percentile had a sensitivity of 61.1% and a false-positive rate of 3.2%. An abnormal prenatal screen was defined as a urine beta-core level > or = 97th percentile, increased nuchal thickness (> or = 5 mm), or the presence of gross structural defects. Corresponding values for the screening efficiency of an abnormal prenatal screen were sensitivity of 77.8% and a false-positive rate of 4.1%. With an abnormal prenatal screen the odds ratio is 82.8 (95% confidence interval 22.6 to 364.9) for having a Down syndrome fetus.

CONCLUSION

The presence of an abnormal maternal urine beta-core level, a gross ultrasonographic anomaly, or increased nuchal thickness had a high detection rate and a low false-positive rate for Down syndrome. This novel screening algorithm is useful for further delineating the risk status in patients at high risk who are reluctant to undergo or decline genetic amniocentesis.

Subtle ultrasonographic anomalies: do they improve the Down syndrome detection rate?

OBJECTIVE

Our purpose was to determine whether the identification of subtle anomalies further improves Down syndrome detection over standard ultrasonographic biometry and the detection of gross morphologic defects.

STUDY DESIGN

The screening efficiency of clinodactyly, dilated renal pelvis (> or =4 mm), echogenic bowel, mild ventriculomegaly (> or =10 to 15 mm), and two-vessel cord was determined prospectively in midtrimester fetuses at amniocentesis. The screening efficiency of increased nuchal thickness and shortened long-bone length (standard biometry) and gross morphologic defects was determined for comparison. Multiple backward stepwise regression analysis was used to determine which subtle anomalies significantly correlated with Down syndrome detection rate and whether they increased Down syndrome detection over that with standard biometry and morphologic defects.

RESULTS

Although all subtle anomalies except two-vessel cord correlated with the presence of Down syndrome on univariate analysis, only echogenic bowel (Wald chi2 = 15.0211, p = 0.0001) and clinodactyly (Wald chi2 = 9.4273, p = 0.002) persisted in regression analysis of the subtle anomaly group. When either of the above-described anomalies was present, the detection rate for Down syndrome was 28.6%, p < 0.00001. For the combination of standard biometry (either increased nuchal thickness or short humerus) or gross anatomic defect, Down syndrome detection rate was 53.3% (p < 0.00000001). This increased to 63.2% (p < 0.00000001) when subtle anatomic defects (either echogenic bowel or clinodactyly) were included in the definition of an abnormal sonogram.

CONCLUSION

Subtle anomalies, of which echogenic bowel and clinodactyly are the most significant, further increase Down syndrome screening efficiency over standard biometry or the finding of gross anatomic defect. Our data appear to support the addition of subtle anomaly findings to ultrasonographic screening for Down syndrome.

Screening for Down syndrome using urine hCG free beta-subunit in the second trimester of pregnancy

Human chorionic gonadotropin (hCG) free beta-subunit levels were determined in 709 control and 13 Down syndrome urine samples from the second trimester of pregnancy. Results were normalized to urine creatinine concentration and converted to multiples of the unaffected pregnancy medium (MOM). The concentration of free beta-subunit in Down syndrome cases was 3.9 MOM. Seven of 13 Down syndrome pregnancies (54 per cent) had free beta-subunit levels at or above the 95th centile of unaffected pregnancies. Urine free beta-subunit may potentially be useful as a screening test for Down syndrome.

First-trimester growth restriction and fetal aneuploidy: the effect of type of aneuploidy and gestational age

OBJECTIVE

Our purpose was to determine the effect of type of aneuploidy and gestational age on first-trimester fetal growth.

STUDY DESIGN

Crown-rump length measurement was obtained in pregnancies undergoing chorionic villus sampling in three large prenatal diagnosis centers. One hundred forty-four aneuploid fetuses, from 9 to 13 weeks' gestation, were compared with 440 matched control fetuses for evidence of crown-rump length shortening. Shortening was defined by the observed/expected crown-rump length. Expected values of crown-rump length based on last menstrual period were obtained from regression equations generated from a separate normal group. Threshold values for aneuploidy screening were determined on the basis of receiver-operator characteristic curves.

RESULTS

There was significant crown-rump length shortening in trisomy 18 compared with normal fetuses, with observed/expected values < or = 0.80 (odds ratio 13.78, 95% confidence interval 5.64 to 33.88, p < 0.000001); for trisomy 13 the observed/expected crown-rump length was < or = 0.90 (odds ratio 3.64, 95% confidence interval 1.08 to 12.96, p < 0.03). There was no significant shortening of crown-rump length in Down syndrome, with observed/expected values < or = 0.92 (odds ratio 0.86, 95% confidence interval 0.50 to 1.47, p = 0.6). With shortened crown-rump length (observed/expected value < 0.86) the risk of any aneuploidy is increased (odds ratio 2.52, 95% confidence interval 1.6 to 3.96, p < 0.0001). When the first-trimester crown-rump length was shortened by > or = 14 mm, the aneuploidy risk was high (odds ratio 9.04, 95% confidence interval 3.26 to 28.67, p < 0.00001).

CONCLUSION

In the first trimester fetuses with trisomy 18 and 13 appear to be growth restricted, in contrast to fetuses with trisomy 21. In at-risk pregnancies crown-length that is shorter than expected significantly increase the odds that aneuploidy is present.

Controlled release of proteins to tissue transplants for the treatment of neurodegenerative disorders

Alzheimer's disease involves substantial cholinergic cell deficits; other neurodegenerative diseases involve similar losses of certain cell populations. Optimal therapies may involve tissue replacement coupled with the controlled delivery of appropriate growth factors, such as nerve growth factor, to the graft site. In this review article we describe the kinetics of protein release from three modes of controlled protein delivery to transplants: delivery from a polymer matrix, delivery form polymeric microspheres, and delivery from genetically engineered cells. The efficacy and feasibility of each of these delivery strategies for potential treatment of patients diagnosed with neurodegenerative disorders is discussed.

Ultrasonographically adjusted midtrimester risk of trisomy 21 and significant chromosomal defects in advanced maternal age

OBJECTIVE

Our purpose was to determine whether normal midtrimester ultrasonography results reduces the risk of fetal Down syndrome and any clinically significant chromosomal defects in pregnancies with advanced maternal age and to develop risk tables on the basis of age and ultrasonographic results.

STUDY DESIGN

Biometry data were obtained in 4079 women between 15 and 24 weeks undergoing amniocentesis for maternal age. Expected values of humerus, femur, both combined, and abdominal circumference based on biparietal diameter were generated from a normal group. Observed/expected values of each parameter and nuchal thickness > or = 6 mm was used to screen for Down syndrome and any clinically significant chromosome defects. Receiver-operator characteristic curves were used to determine threshold screening values for each parameter. By use of stepwise logistic regression the optimal measurements for detection of chromosome anomalies were established. An abnormal ultrasonography result was defined as either abnormal biometry choroid plexus cysts or a structural defect.

RESULTS

The finding of shortened humerus (observed/expected < 0.90), abnormal nuchal thickness, or an anatomic defect had the highest sensitivity for Down syndrome detection, 70.6%, p < 0.0001, whereas a short humerus, small abdominal circumference, (observed/expected < 0.92), or an anatomic defect had a sensitivity of 46.7%, p < 0.0001, for any significant chromosome defect. With a normal ultrasonography the risk of Down syndrome in a 39-year-old woman falls from 1:100 to < 1:292.

CONCLUSION

A normal ultrasonography substantially reduces the risk of Down syndrome and any chromosome abnormality. This information is useful in counseling women who decline amniocentesis on the basis of maternal age.

Risk of Down syndrome and any clinically significant chromosome defect in pregnancies with abnormal triple-screen and normal targeted ultrasonographic results

OBJECTIVE

Our purpose was to study prospectively the use of ultrasonographic biometry to refine the risk estimates for both Down syndrome and any clinically significant chromosome defect in women with abnormal biochemical triple-screen results.

STUDY DESIGN

Ultrasonographic biometry and anatomic survey were performed on study and control cases. Expected values for humerus, femur, combined humerus plus femur lengths, and abdominal circumference were generated on the basis of biparietal diameter obtained from a normal group. Threshold observed/expected values of each measurement for screening for Down syndrome and clinically significant chromosome defects were determined with receiver-operator characteristic curves. By stepwise logistic regression analysis the optimal screening parameters, including nuchal thickness, for detection of Down syndrome and clinically significant chromosome defect were determined. Risk tables for chromosome anomalies were developed on the basis of ultrasonography and triple-screen values.

RESULTS

Of 1034 cases at risk for Down syndrome (risk > or = 1/270) or trisomy 18 on the basis of triple-screen results, there were 11 cases of Down syndrome, 1 of trisomy 18, and 17 clinically significant chromosome defects. Abnormal nuchal thickness or observed/expected humerus length < 0.92 was the most sensitive parameter for Down syndrome detection. Abnormal nuchal thickness or observed/expected combined femur and humerus length < 0.90 was the most sensitive for significant chromosome defects. With abnormal biometry or anatomy the Down syndrome risk was 8 of 127 versus 1 of 753 in normals, odds ratio 50.4 (95% confidence interval 6.4 to 90.2), p < 0.00001, and the risk of significant defects was 11 of 90 versus 6 of 830 in normals, odds ratio 19.3 (95% confidence interval 6.4 to 60.5), p < 0.00001. In a pregnancy with a 1 in 270 triple-screen risk for Down syndrome, normal biometric and anatomic results reduce the risk to 1 in 2100.

CONCLUSION

Normal ultrasonographic anatomy and biometry significantly reduces the risk of both Down syndrome and any significant chromosome defects in pregnancies with abnormal triple-screen results.

Prenatal detection of two different monosomic cell lines by chorionic villus sampling

We present a prenatal case of mosaicism with at least two monosomy cell lines: one with monosomy 21 (45,XY,-21) and one missing the Y (45,X) and a possible third 46,XY in chorionic villus cell culture. Cytogenetic studies were initiated following the ultrasound detection at 11 weeks of a large cystic hygroma and in utero growth retardation. Spontaneous fetal demise occurred at 12 weeks and the pregnancy was terminated. To our knowledge, this is the first report of two different monosomic cell lines found in chorionic villus cells.

Normal nuchal thickness in the midtrimester indicates reduced risk of Down syndrome in pregnancies with abnormal triple-screen results

OBJECTIVE

Our purpose was to determine whether nuchal thickness measurement can identify the euploid fetuses in midtrimester pregnancies at increased risk for Down syndrome on the basis of maternal age and serum screening.

STUDY DESIGN

Nuchal thickness was obtained prospectively in 651 consecutive fetuses at 14 to 21 weeks' gestation and at > or = 1:270 risk for Down syndrome on the basis of unconjugated estriol, alpha-fetoprotein, and human chorionic gonadotropin levels. The risk of Down syndrome with a normal nuchal thickness was determined. A receiver-operator characteristic curve was used to determine a serum-based risk threshold below which the risk for Down syndrome was low. The prevalence of Down syndrome in fetuses with both a normal nuchal thickness and a below-serum-risk threshold was compared with prevalence in either those above threshold risk or with an abnormal nuchal thickness.

RESULTS

There were eight cases of trisomy 21 and one case each of 46,XX/47,XXX, 46,XY/47,XY, +7, and 46,XX, 11q-. The sensitivity of an abnormal nuchal thickness (> or = 6 mm) for detecting Down syndrome was four in eight (50%) (95%) confidence interval 15.3% to 84.6%). The risk of Down syndrome was significantly increased with an abnormal compared with a normal nuchal thickness, four in 13 (30.8%) versus four in 638 (0.6%), p < 0.0001. A risk threshold was defined at > or = 1:100 on the basis of the receiver-operator characteristic plot. Of 390 cases with a normal nuchal thickness and a serum risk estimate < 1:100, there were no cases of Down syndrome (0/390 vs 8/253, p = 0.002).

CONCLUSION

Normal nuchal thickness significantly reduces the risk of Down syndrome and may help reduce the number of amniocenteses done for abnormal triple screen results.

Cognition and causation in human experience

Arguments that thoughts cannot have the power to cause or influence behavior are briefly addressed. Despite being couched in traditional behavioristic terminology, some of these arguments actually invoke the very dualism that they criticize. Likewise problematic are portrayals of scientific activity as being necessarily grounded in an ontology of physical extension and an epistemology that grants the visual system (and hence observability) sole and supreme authority. Contemporary cognitivists challenge classical mind-body dualism and refer to thoughts and other "mental" phenomena as activities of the living system. Three conclusions are drawn: (1) humans think, (2) human thinking influences human behavior, and vice-versa, and (3) dialogues on this topic would be well served by a refinement of the questions under consideration.

First-trimester endocervical irrigation: feasibility of obtaining trophoblast cells for prenatal diagnosis

We sought to determine the feasibility of obtaining trophoblast cells for first-trimester prenatal diagnosis using endocervical irrigation. We studied 20 pregnant patients between 7-10.5 weeks' gestation who presented for elective pregnancy termination. Under ultrasound guidance, a specially designed plastic catheter was advanced to the level of the internal cervical os. Gentle flushing and aspiration was performed with 3 mL of normal saline. The material obtained was fixed and stained. A placental pathologist identified trophoblast cells using light microscopy. In another five cases, we attempted to culture the endocervical washings. Trophoblast cells were identified by microscopy after staining the cultured material with an anti-alpha-hCG-antibody bound stain. In ten of 20 cases (50%), trophoblast material was retrieved on irrigation. Of the five additional cases on which culture was attempted, trophoblast was successfully cultured in one, the results were equivocal in two, and culture was unsuccessful in the other two. Trophoblast cells for prenatal diagnosis can be obtained in a significant percentage of cases by first-trimester endocervical irrigation. The advantages of irrigation include technical simplicity, brief duration (less than 3 minutes), and suitability to first-trimester diagnosis. Further testing is necessary to determine the risks.

Hyperechoic fetal bowel: the perinatal consequences

A number of publications have reported an association between the finding of hyperechoic fetal bowel on prenatal sonogram and disorders such as aneuploidy and cystic fibrosis. To define more precisely the significance of this finding, we systematically reviewed the published material on the subject. Based on a total of 357 reported cases, we documented a high prevalence of cystic fibrosis (25.6 per cent) and chromosome abnormality (12.4 per cent) associated with increased bowel echogenicity in the fetus. High rates of intrauterine growth retardation (14.9 per cent), fetal demise (9.0 per cent), and prematurity (15.3 per cent) were also found. The data were obtained from a population at high a priori risk for aneuploidy and included fetuses at 1 in 4 risk for cystic fibrosis reported in two studies. This increased the bias towards an adverse outcome. The rate of complications when a hyperechoic abdomen is noted in a low-risk fetal population has so far not been delineated. Although the high frequency of complications found is of concern and warrants investigation, extrapolation of these risk figures to a fetal population at low a priori risk may not be appropriate.

Unusual inheritance of primary ciliary dyskinesia (Kartagener's syndrome)

Primary ciliary dyskinesia syndrome is characterised by chronic sinusitis, bronchiectasis, and, in 50% of cases, dextrocardia. It is generally believed to be inherited as an autosomal recessive disorder. In this report, we describe a family consisting of a mother and her five male children, the offspring of three different fathers, all of whom have this syndrome. This argues for either an X linked or autosomal dominant pattern of inheritance. Cytogenetic and FISH (fluorescent in situ hybridisation) analyses were done on the mother and one son and were found to be normal.

The use of averaged electrode voltages to assess the function of nucleus internal cochlear implant devices in children

Averaged electrode voltages (AEVs) provide an objective measure of the output of the Nucleus multichannel cochlear implant device. AEVs are the peak-to-peak voltages of each electrode in the internal array and are recorded from electrodes placed on the scalp. This article summarizes average voltage data for 25 children with complete insertions of the electrode array. Data are compared with previously published adult data and are evaluated based on the location of the recordings (clinic versus operating room). AEV data can be applied clinically to identify implant problems. AEV recordings for this purpose are particularly important with children who may not be able to provide accurate reports of implant function. Case studies are presented to illustrate the application of the AEV procedure to examine implant malfunction in six children.

First-trimester prenatal diagnosis of osteogenesis imperfecta type II by DNA analysis and sonography

Osteogenesis imperfecta type II was diagnosed prenatally by analysis of DNA obtained from chorionic villus sampling (CVS) performed at 12 weeks of gestation in a woman who previously had had an affected child. The father had been shown to be mosaic for a mutation in the gene (COL1A2) which encodes the alpha 2(I) chain of type I collagen. An affected fetus was predicted by detection of the mutation in amplified chorionic villus genomic DNA. Ultrasound examination at 13 weeks 4 days demonstrated femoral deformity and virtual absence of calvarial mineralization. In pregnancies at risk for osteogenesis imperfecta type II, sonographic evidence of skeletal abnormalities may be evident by 13 weeks' gestation.

Follow-up of pregnancies complicated by placental mosaicism diagnosed by chorionic villus sampling

Thirty-nine (2.3 per cent) of 1724 chromosome studies from diagnostic chorionic villus samplings (CVS) done between 1983 and 1990 showed either level III (true) mosaicism (1.2 per cent) or level II (pseudo-) mosaicism (1.1 per cent) for chromosomal aneuploidy. Follow-up information on these 39 pregnancies was collected from questionnaires to families, paediatricians, and obstetricians. For all cases in which the pregnancy was continued and further testing was accomplished, the mosaicism was felt to be confined to the placenta. As compared with a control group of pregnancies evaluated by CVS with normal karyotypes, there was no increased incidence of pregnancy loss, congenital malformations, or developmental delay in the infants. Although intrauterine growth retardation occurred in several of the level III mosaic cases, adequate catch-up growth has been demonstrated.

Transabdominal thin-gauge embryofetoscopy: a technique for early prenatal diagnosis and its use in the diagnosis of a case of Meckel-Gruber syndrome

OBJECTIVE

Our aim was to develop and evaluate a transabdominal endoscopic technique to visualize the embryo or fetus with thin-gauge needles and submillimetric fiberoptic endoscopes.

METHODS

Under ultrasonographic guidance, an 18- or 19-gauge thin-wall needle was introduced into the uterus of 28 patients undergoing first-trimester or early second-trimester termination of pregnancy. A 0.7 mm endoscope was threaded through the lumen of the needle after removal of the stylet. Visualization of the embryo-fetus was attempted before 14 weeks' gestation (n = 20). From 16 to 20 weeks (n = 8), the needle and endoscope were directed to the placental insertion of the umbilical cord, and a cordocentesis was performed.

RESULTS

Excellent visualization of the surface anatomy of fetuses from 7 to 13 weeks was obtained in 85% of cases (17/20). A diagnosis of Meckel-Gruber syndrome was made at 11 weeks' menstrual age by visualizing postaxial polydactyly and an occipital encephalocele. Endoscopically assisted cordocentesis allowed visualization of the lumen of the umbilical vein and of the blood flow within it.

CONCLUSION

Endoscopic visualization of the embryo or fetus can be performed transabdominally in the first trimester with small-delivered endoscopes. This represents a clear advantage over previous endoscopic approaches to the human pregnancy. Potential applications of this technique include a precise description of fetal anatomy and physiologic features, diagnosis of anomalies, and therapeutic fetal interventions.

Introduction to special section: theoretical developments in the cognitive psychotherapies

The cognitive psychotherapies have developed and substantially differentiated since their inception in the 1950s. Six major themes in their theoretical development are discussed: (a) the differentiation of rationalist and constructivist therapies and metatheories of knowing; (b) the acknowledgement of social, biological, and embodiment processes in therapy; (c) the recognition of unconscious processes; (d) an increasing focus on self-organizing and self-protective processes in life span personality development, with such processes being embedded in interpersonal and social system dynamics; (e) a shift toward different views of emotionality and the incorporation of experiential techniques; and (f) a synergistic involvement in the psychotherapy integration movement. The cognitive psychotherapies reflect remarkable activity, a point illustrated and elaborated in the articles that constitute this special section.