Fetal 'space-suit' hydrops in the first trimester: differentiating risk for chromosome abnormalities by delineating characteristics of nuchal translucency.

Detecting first trimester fetuses with pan-body hydrops, giving the appearance of a 'space-suit,' is associated with a marked increased risk for chromosome abnormalities. In 30 consecutive fetuses prospectively characterized by space-suit hydrops, detected at or before 13.9 weeks' gestation, 26 (86.7%) were characterized by chromosome abnormalities. However, as opposed to the preponderance of autosome abnormalities among first-trimester fetuses with prominent nuchal translucencies, 15 of the 26 fetuses (57.7%) with abnormal complements were characterized by sex chromosome aneuploidies. Genetic counselling and consideration of invasive prenatal testing is warranted when space-suit hydrops is detected in the first trimester.

Cartilage-hair hypoplasia syndrome: implications for prenatal diagnosis.

Cartilage-hair hypoplasia (CHH) is a rare autosomal recessive skeletal dysplasia characterized by short stature, sparse hair, and a variable degree of immunodeficiency. We describe here the prenatal diagnosis of CHH in a woman who was previously delivered of a similarly affected infant. In addition, we review the prenatal diagnostic implications of the localization, by linkage analysis, of the gene responsible for many cases of CHH.

Prenatal diagnosis of genital anomalies.

OBJECTIVES: This is a report of five cases of abnormal fetal genitalia detected by routine prenatal ultrasound. METHODS: Retrospective review was conducted to identify all cases of abnormal fetal genitalia identified by routine obstetrical ultrasound at our institution in which postpartum follow-up was available. RESULTS: Five cases of prenatal sonographically diagnosed abnormal fetal genitalia were confirmed postnatally. The abnormalities include ambiguous genitalia, severe hypospadias with unilateral cryptorchidism, megalourethra, and concealed penis. In all cases, other anomalies were discovered during the prenatal ultrasound. CONCLUSIONS: Prenatal ultrasound may detect a variety of abnormalities of the fetal genitalia.

Remote real-time ultrasound interactive telediagnosis: putting it into practice.

Teleradiology, the practice of radiology over a distance via electronic transmission of radiologic images, has the potential to fundamentally alter the practice of radiology in the years to come. Different models for the practice of teleradiology include on-call reading, consultation and overreading, primary-reading teleradiology, and integration with picture archiving and communication system (PACS) and miniPACS. Remote real-time ultrasound telediagnosis represents a specialized subset of primary-reading teleradiology, specifically designed to involve the radiologist directly with sonographer in the performance of the ultrasound examination. This type of practice involves rapid transmission of patient demographics and captured still images and live transmission of the real-time video output of the ultrasound machine. When utilized properly real-time telediagnosis extends the high standards of tertiary center sonographic diagnosis out to community and rural sites.

Isolated fetal choroid plexus cysts and trisomy 18: a review and meta-analysis.

OBJECTIVE: Risk of trisomy 18 in a fetus with ultrasonographic diagnosis of choroid plexus cysts and no other anomalies is controversial. Using our data and current literature, we performed a meta-analysis and estimated the positive predictive value of isolated choroid plexus cysts for trisomy 18. STUDY DESIGN: Between Jan. 1, 1989, and Dec. 31, 1992, all women undergoing ultrasonographic examination at our institution were prospectively evaluated for fetal choroid plexus cysts and cytogenetic outcome. In addition, all reports dealing with fetal choroid plexus cysts obtained from MEDLINE (1983 through 1992) were assessed. Only prospective studies with > 10 cases of choroid plexus cysts were further evaluated to determine the total number of fetuses with choroid plexus cysts and otherwise normal sonograms. Frequency of aneuploidy was determined by analysis of our data and the included studies. To estimate the positive predictive value of choroid plexus cysts from trisomy 18, a theoretic 2 x 2 table was constructed with values available from the literature. RESULTS: Eighty fetuses with choroid plexus cysts were identified in our unit. Of 74 fetuses with isolated choroid plexus cysts, there were no cases of trisomy 18. Meta-analysis identified 2 cases of trisomy 18 among 748 fetuses with isolated cysts (1/374). To derive a positive predictive value of isolated choroid plexus cysts for trisomy 18, we reviewed the literature and found a total of 50 fetuses with trisomy 18 who underwent ultrasonographic examination in the midtrimester. There were 3 cases of isolated choroid plexus cysts, and 12 of 50 (24%) had otherwise normal ultrasonographic results. Using a midtrimester incidence of 1 in 2461 for trisomy 18 (Hsu LYF. In: Milunsky A, ed. Genetic disorders of the fetus. 3rd ed. Baltimore: Johns Hopkins University Press, 1992: 155-210; Hook et al. Am J Hum Genet 1989; 45:855-61) and a prenatal prevalence of 0.95% for choroid plexus cysts (based on a review of the literature), we obtained a positive predictive value of 1 in 390. CONCLUSION: On the basis of the risk for trisomy 18 obtained from our meta-analysis (1/374) and its close approximation to the estimated positive predictive value (1/390), our data do not support the routine offering of invasive prenatal cytogenetic testing in cases of isolated choroid plexus cysts.

Clinical course and outcome of fetuses with isolated cystic nuchal lesions and normal karyotypes detected in the first trimester.

OBJECTIVE: We assessed newborn outcome and infant development in cases of first-trimester fetal cystic nuchal lesion and normal karyotype. STUDY DESIGN: Information regarding newborn outcomes and infant growth and development was prospectively obtained from 32 consecutive pregnancies characterized by fetal cystic nuchal lesions detected in the first trimester (< or = 13.9 weeks' gestation) and normal karyotypes. RESULTS: Cystic nuchal lesions spontaneously resolved by the twentieth gestational week in 31 cases; all 31 infants had normal results at newborn examination and demonstrated normal growth and development at 12 months of age. Resolution did not occur in one case; prominent hygromas were repaired at birth with normal growth and development through 2 1/2 years of age. CONCLUSIONS: In most affected fetuses with normal karyotypes, spontaneous resolution will occur with favorable newborn and infant outcomes. However, patients should be counseled that resolution may not occur or that nonchromosome abnormalities may result in a less favorable outcome.

Severity of abnormality influences decision to terminate pregnancies affected with fetal neural tube defects.

We examined parental decision concerning pregnancy management in women having fetuses with neural tube defects (NTDs) to determine whether severity of defect or method of detection has an impact on the decision making process. Analysis of decisions by 50 women, whose pregnancies were affected by an isolated neural tube defect (NTD) and characterized by a singleton gestation at 24 gestational weeks or less with normal chromosomal complement (46,XX or 46,XY), were assessed. All 23 women carrying fetuses with anencephaly elected to terminate their pregnancies. Of the 27 women carrying fetuses with spina bifida, 21 (77.8%) elected to terminate their pregnancies and 6 (22.2%) elected to continue their pregnancies. Of the 6 pregnancies that were continued, 4 were initially detected by ultrasonography and 2 were ascertained by maternal serum alpha-fetoprotein screening; defects ranged from 2 to 14 vertebral bodies, and none of the defects were craniad to the T9 level. This is in comparison to 5 of the 21 spina bifida cases that were elective pregnancy terminations, which were characterized by fetal lesions craniad to the T9 level. Severity of NTD thus appears to influence the decision to continue or terminate an affected pregnancy.

Significance of septations in isolated fetal cystic hygroma detected in the first trimester.

Recent reports have indicated an increased risk for fetal chromosome abnormalities, especially autosomal trisomy, in fetuses with isolated cystic hygroma, or prominent nuchal membranes, detected by ultrasonography during the first trimester. However, these reports present contradictory information regarding the prognostic significance of septations within the cystic hygroma. We evaluated, in blind fashion, 55 consecutive cases of isolated fetal cystic hygroma detected at or before 13.9 weeks' gestation to determine the association between septations and fetal chromosome complement. Septations were associated (P < 0.05) with an increased risk for fetal chromosome abnormalities. However, the incidence of chromosome abnormalities was also increased (12.5 per cent) among cases not characterized by septations. Thus, we believe it prudent to offer invasive prenatal testing to all women found to be carrying fetuses with cystic hygroma, irrespective of the presence or absence of septations.

Ultrasound-guided fetal skin sampling for prenatal diagnosis of genodermatoses.

OBJECTIVE: To evaluate the safety and diagnostic efficacy of ultrasound-guided fetal skin sampling for the prenatal diagnosis of genodermatoses. METHODS: Seventeen pregnancies seen over 6.5 years were analyzed retrospectively. Fifteen were at risk for junctional epidermolysis bullosa and two for recessive dystrophic epidermolysis bullosa. Under ultrasound guidance, a biopsy forceps was inserted through a 14-gauge catheter and directed toward the fetus (thorax, back, or buttocks) to obtain skin samples. The procedures were performed at a mean of 18.3 weeks' gestation (range 16.5-19.5). RESULTS: Fetal skin sampling was successful in all cases; the mean number of biopsies taken was 3.6 (range two to five). Five of the 17 fetuses were determined to be affected, each with junctional epidermolysis bullosa; these pregnancies were terminated electively and the prenatal diagnoses confirmed. The remaining 12 pregnancies resulted in the delivery of healthy infants at or after 37 weeks' gestation. There were no pregnancy-related complications, specifically preterm rupture of the membranes or preterm labor. Three of the 12 infants had minor skin blemishes believed to be due to the skin sampling. CONCLUSION: Ultrasound-guided fetal skin sampling is the procedure of choice when fetal skin is required for prenatal diagnosis of genodermatoses.

Predicting pregnancy survival from a single first trimester vaginal ultrasonogram.

This retrospective study evaluates early first trimester FHR, gestational SACD, and CRL measurements as means to predict ultimate pregnancy outcome. Outcomes of 274 pregnancies were monitored a single time by transvaginal ultrasonography with measurements recorded between 5.0 and 9.0 weeks' gestation. The measurements were then correlated with the pregnancy outcomes. FHR (P < 0.0001), gestational SACD (P = 0.0002), and CRL (P = 0.0059) each correlated positively with a successful pregnancy outcome. Measurements from a single transvaginal ultrasonogram can be used to predict a successful pregnancy outcome in the early first trimester.

Prenatal diagnosis of isolated bilateral microphthalmia with confirmation by evaluation of products of conception obtained by dilation and evacuation.

We describe the prenatal diagnosis of isolated bilateral fetal microphthalmia in a woman at increased risk of having a fetus with microphthalmia. Ultrasound examinations at 16.1 and 19.5 weeks' gestation demonstrated bilateral fetal microphthalmia with no other associated structural defects. The patient elected to terminate her pregnancy at 19.5 weeks. Pathological evaluation of the products of conception obtained by dilation and evacuation confirmed the prenatal diagnosis of isolated bilateral fetal microphthalmia.

Predicting aneuploidy in fetuses with cardiac anomalies: significance of visceral situs and noncardiac anomalies.

To determine whether the risk of aneuploidy in fetuses with cardiac anomalies is affected by abnormal visceral situs or coexisting noncardiac anomalies (NCA), were reviewed 125 cases in which a structural cardiac anomaly was detected by prenatal sonography. Forty-three of the 125 fetuses (34%) had an abnormal karyotype (31 autosomal trisomies, 12 other). None of the 13 fetuses with abnormal visceral situs had an abnormal karyotype, whereas an abnormal karyotype was present in 43 of 112 with normal visceral situs (P < 0.01, Fisher's exact test). The karyotype was abnormal in 33 of 52 (63%) with coexisting NCA and in only 10 of 73 (14%) without coexisting NCA (P < 0.001, chi-square). Therefore, among fetuses with structural cardiac anomalies, abnormal visceral situs is strongly predictive (100% in our series) of normal karyotype, whereas the presence of coexisting NCA significantly increases the risk of aneuploidy. These findings can help guide recommendations concerning prenatal karyotyping.

Transvaginal chorionic villus sampling using transabdominal ultrasound guidance: a new technique for first-trimester prenatal diagnosis.

Transvaginal chorionic villus sampling (CVS) using concurrent transabdominal ultrasound guidance was performed in 20 women who desired CVS but could not be offered transcervical or transabdominal approaches because of uterine position and placental location. Satisfactory amounts of chorionic villi were obtained in all 20 cases with no maternal discomfort, an occurrence that contrasts with our experience in transvaginal CVS using endovaginal ultrasound guidance. We believe that transvaginal CVS using concurrent transabdominal ultrasound guidance warrants consideration as an alternative technique for first-trimester CVS in selected patients.

High frequency of cytogenetic abnormalities in fetuses with cystic hygroma diagnosed in the first trimester.

OBJECTIVE: The purpose of this study was to evaluate the association between fetal cystic hygroma detected in the first trimester and fetal cytogenetic abnormalities. METHODS: Visualization of a prominent (2.5 mm or larger) anechoic or hypoechoic separation of the fetal skin line from the posterior body wall led to the diagnosis of fetal cystic hygroma; presence or absence of septations within the cystic hygroma was documented in each patient. Fetuses with additional structural defects were excluded from this study. All eligible women were offered prenatal cytogenetic studies (ie, chorionic villus sampling, amniocentesis). RESULTS: Cytogenetic studies were performed on all 32 affected fetuses. Fifteen of 32 fetuses (46.9%) had abnormal complements. Septations within the cystic hygroma were demonstrated in 18 fetuses; nine of these had abnormal karyotypes. Of the 12 women carrying fetuses with normal chromosome complements who elected to continue their pregnancies, 11 delivered infants with no evidence of cystic hygroma. CONCLUSIONS: Prenatal cytogenetic analysis should be offered to women with fetal cystic hygroma diagnosed in the first trimester. Normal outcome is likely in those showing no chromosome abnormalities.

Diagnostic efficacy of endovaginal color Doppler flow imaging in an ectopic pregnancy screening program.

The authors compared the diagnostic yield of endovaginal color and pulsed Doppler ultrasound (US) in conjunction with endovaginal sonography with that of endovaginal sonography alone in patients prescreened to be at increased risk for ectopic pregnancy. Pelvic structures were evaluated for overall vascularity and for the presence of characteristic pulsed Doppler US velocity waveforms. The diagnostic sensitivity of the initial endovaginal sonographic examination increased with the addition of color and pulsed Doppler US, from 71% to 87% for ectopic pregnancy, from 24% to 59% for failed intrauterine pregnancy, and from 90% to 99% for viable intrauterine pregnancy. Specificities for endovaginal sonography with color and pulsed Doppler US ranged from 99% to 100%. Use of endovaginal color and pulsed Doppler US increased the percentage of diagnostic initial sonographic examinations from 62% to 82%. The improved diagnostic sensitivity of endovaginal color Doppler US for ectopic pregnancy may ultimately result in earlier treatment, with reduced morbidity and mortality.