White matter abnormalities are related to microstructural changes in preterm neonates at term-equivalent age: a diffusion tensor imaging and probabilistic tractography study

BACKGROUND AND PURPOSE

Preterm infants have a high risk of brain injury and neurodevelopmental impairment, often associated with WMA on conventional MR imaging. DTI can provide insight into white matter microstructure. The aim of this study was to investigate the association between WMA on conventional MR imaging and DTI parameters in specific fibers in preterm neonates at term-equivalent age.

MATERIALS AND METHODS

Seventy preterm neonates (39 boys and 31 girls) were included in the study. WMA were classified as no, mild, moderate, or severe. Probabilistic tractography provided tract volumes, FA, MD, λ(//), and λ(⊥) in the CST, SLF, TRs, and corpus callosum. Data were compared by using MANOVA, and adjustment for multiple comparisons was performed.

RESULTS

Important associations were found between WMA and microstructural changes. Compared with neonates with no WMA (n = 41), those with mild WMA (n = 27) had significantly increased λ(⊥) and MD in the left ATR, the left sensory STR, the bilateral motor STR, and for λ(⊥) also in the right CST; FA decreased significantly in the left sensory STR. Diminished tract volumes and altered diffusion indices were also observed in the 2 neonates with moderate WMA.

CONCLUSIONS

Altered DTI indices in specific tracts, with λ(⊥) as most prominent, are associated with mild WMA in preterm neonates at term-equivalent age.

Gender differences in language and motor-related fibers in a population of healthy preterm neonates at term-equivalent age: a diffusion tensor and probabilistic tractography study

BACKGROUND AND PURPOSE

Sex differences in white matter structure are controversial. In this MR imaging study, we aimed to investigate possible sex differences in language and motor-related tracts in healthy preterm neonates by using DTI and probabilistic tractography.

MATERIALS AND METHODS

Thirty-eight preterm neonates (19 boys and 19 girls, age-matched), healthy at term-equivalent age and at 12 months were included. TBV was measured individually. Probabilistic tractography provided tract volumes, relative tract volumes (volume normalized to TBV), FA, MD, and λ(⊥) in the SLF, in the TRs, and in the CSTs. Data were compared by using independent t tests, and Bonferroni corrections were performed to adjust for multiple comparisons.

RESULTS

We showed that healthy preterm boys had larger TBV than girls. However, girls had statistically significantly larger relative tract volumes than boys bilaterally in the parieto-temporal SLF, and in the left CST. Moreover, in the left parieto-temporal SLF, a trend toward lower MD and λ(⊥) was observed in females.

CONCLUSIONS

Structural sex differences were found in preterm neonates at term-equivalent age in both sides of the parieto-temporal SLF and in the left CST. Further studies are necessary to investigate whether these structural differences are related to later sex differences in language skills and handedness or to the effect of prematurity.

Pediatric outcome of children with the prenatal diagnosis of isolated septal agenesis

BACKGROUND

Isolated Septal Agenesis (SA) is a rare disease with clinical outcomes (especially neurological outcomes) that are unknown. The purpose of this study was to evaluate the clinical outcome of these children.

METHODS

We conducted a retrospective multicenter study of 17 children with an isolated SA or SA combined with a moderate ventricular dilatation (VD) that was diagnosed antenatally and confirmed by a magnetic resonance imaging (MRI) performed in the antenatal period.

RESULTS

Of the 17 children, 14 had normal neurological examinations, 2 had language development delay and visuo-spatial dyspraxia, and 3 of the 17 children had behavioral problems. Eight children had neuropsychological evaluations, and the results were normal in six cases. There were 3 cases of septo-optic dysplasia (SOD) diagnosed postnatally, which highlighted the difficulties in assessing the optic tract and hypothalamic-pituitary region in antenatal imaging. Language delay and behavioral disorders were the main abnormalities at follow-up.

CONCLUSION

The discovery of an isolated SA reveals the difficulties of prenatal diagnosis to correlate the neurological and functional prognosis to morphological findings. The prognosis seemed to be good. It appears necessary to improve the diagnostic performance of fetal brain imaging and to follow-up these children prospectively to assess their long-term cognitive-behavioral outcomes.

Fetal intracranial tumors: a review of 27 cases

Fetal intracranial tumors are rare. The diagnosis is generally made on histology after birth. The aim of this study was to analyze clinical and imaging data in a series of fetal intracranial tumors and emphasize the findings that may help approach the diagnosis antenatally. We retrospectively analyzed imaging and clinical findings in 27 cases of fetal intracranial tumors assessed by ultrasound (27/27) and MR imaging (24/27). A histological diagnosis was always obtained. Main diagnoses included 15 germinal tumors (13 teratomas), 4 glial tumors, 2 craniopharyngiomas and 3 hamartomas. Average gestational age at diagnosis was 27 weeks for teratomas, 21 weeks for hamartomas and 34 weeks for glial tumors. All tumors but one were supra tentorial, and the lesion extended in the posterior fossa in two teratomas. A heterogeneous pattern, which was more frequently seen in teratomas, was better visualized by MR than US imaging. In addition, in two cases of teratomas, MR imaging better assessed the extension of the tumor. Teratomas and gliomas are the most frequent brain tumors in the fetus. US and MR imagings appear complementary in the prenatal assessment of these lesions.

Contribution of three-dimensional computed tomography in the assessment of fetal skeletal dysplasia

OBJECTIVE

To compare the diagnostic accuracy of two-dimensional (2D) ultrasound and three-dimensional (3D) computed tomography (CT) for the diagnosis of fetal skeletal anomalies.

METHODS

Eleven pregnant women underwent 2D ultrasound and 3D-CT. Ten fetuses presented skeletal anomalies on 2D ultrasound and one fetus had a normal ultrasound exam but a familial history of osteopetrosis. We compared retrospectively the diagnoses established on 2D ultrasound and 3D-CT with the neonatal and/or postmortem work-up, which were used as the gold standard.

RESULTS

2D ultrasound provided the correct diagnosis in only two of the 11 cases. CT yielded the correct diagnosis in eight; in six of these, 2D ultrasound had been inconclusive. 3D-CT was more accurate than was 2D ultrasound in visualizing vertebral anomalies (abnormal shape of the vertebral bodies, abnormal interpedicular distance), pelvic bone malformations (delayed ossification of the pubic bones, abnormal acetabular shape) and enlarged metaphysis or synostoses in long bones. In three cases, neither 2D ultrasound nor CT provided the correct diagnosis.

CONCLUSION

In this series, which included a variety of skeletal dysplasias, 3D-CT had a better diagnostic yield than did 2D ultrasound. Both imaging techniques are useful in the management of fetal dysplasia; 2D ultrasound is a useful screening test and 3D-CT is a valuable complementary diagnostic tool.

Should determination of the karyotype be systematic for all malformations detected by obstetrical ultrasound?

OBJECTIVE

The aim of this study was to determine whether karyotyping should be performed for every fetal malformation detected in low risk populations.

METHODS

A karyotype was obtained from 428 fetuses examined over a 10-year period after fetal malformation was diagnosed using obstetrical ultrasound. These fetuses were separated into two groups, one with isolated malformations and the other with multiple malformations. The association between each type of malformation and the result of karyotype was evaluated.

RESULTS

Forty-eight chromosomal abnormalities were encountered in 428 fetuses (11.2%). The karyotype was abnormal in 32/343 (9.3%) fetuses with isolated malformations and 16/85 (18.8%) fetuses with multiple malformations (p=0.022). The probability of an abnormal karyotype among the group of isolated malformation depended on the anatomical system involved (p<0.001). Our study demonstrated several isolated malformations without chromosomal abnormality (hydronephrosis with high obstruction, unilateral multicystic dysplastic kidney, gastroschisis, intestinal dilatation, meconium peritonitis, cystic adenomatoid malformation, pulmonary sequestration, tumor, vertebral anomaly).

CONCLUSION

Each fetus with multiple malformations needs a chromosomal analysis. Within the group of isolated malformations, our study emphasizes that medical maternal history and the type of malformation need to be taken into account before performing a fetal karyotype.

Prenatal prognosis of congenital diaphragmatic hernia using magnetic resonance imaging measurement of fetal lung volume

OBJECTIVES

To investigate the correlation between fetal lung volume (FLV), measured with magnetic resonance imaging (MRI), and postnatal mortality in newborns with prenatally diagnosed isolated congenital diaphragmatic hernia (CDH).

METHODS

In a 4-year prospective multicenter study, 77 fetuses with isolated CDH diagnosed between 20 and 33 weeks' gestation underwent fast spin-echo T2-weighted lung MRI. These MRI-FLV measurements were compared with a previously published normative curve obtained in 215 fetuses without thoracoabdominal malformations and with normal ultrasound biometric findings. FLV measurements were correlated with postnatal survival. The mean gestational age at MRI was 31.3 weeks.

RESULTS

The measured/expected FLV ratio was significantly lower in the newborns with CDH who died compared with those who survived (23.6 +/- 12.2 vs. 36.1 +/- 13.0, P < 0.001). When the ratio was below 25%, there was a significant decrease in postnatal survival (19% vs. 40.3%, P = 0.008). Survival was significantly lower for neonates when one lung could not be seen by fetal MRI compared with those fetuses with two visible lungs on MRI (17.9% vs. 62.1%, P < 0.001).

CONCLUSION

In isolated CDH, FLV measurement by MRI is a good predictor of postnatal mortality due to pulmonary hypoplasia.

[Acute myocardial infarction and MRI: a comparison of infarct size by MRI and peak creatine kinase after a first episode]

AIM

To compare the assessment of infarct size using MRI and peak CK value.

POPULATION AND METHODS

16 patients presenting with a first MI and seriall measurement of CK underwent gadolinium-enhanced MRI.

RESULTS

A significant correlation was observed between both estimates of infarct size (r=0.56, p=0.0025). In addition, an inverse correlation was found between residual viability and peak CK (r=-0.51; p=0.043).

CONCLUSION

After a first episode of MI, infarct size estimate by MRI correlates with that determined by peak CK measurement.

[Importance of echocardiography and MRI in periventricular leukomalacia]

Periventricular leukomalacia (PVL) consists of focal coagulation necrosis and of more diffuse and mild white matter involvement as gliosis and lesions of immature oligodendrocytes. PVL affects essentially the premature newborn and has become the dominant form of perinatal neurological insults. Its diagnosis remains difficult to assess as neurological examination is poorly contributive. Diagnostic imaging plays an important role as it completes clinical, biological and electrophysiological data in depicting the cerebral lesions. Cerebral ultrasound remains the first imaging modality to perform in order to investigate and follow ill neonates. However ultrasound has a low sensitivity and specificity in depicting non cavitated PVL. Magnetic resonance imaging (MRI), in the acute stage, provides additional information about the extension and the depiction of hemorrhagic component of the lesions. Furthermore, diffusion-weighted MRI appears useful for the early identification of the diffuse component of PVL. MRI in the chronic stage is the only imaging method to study the progress of myelination and precise the extension of sequellar lesions.

[The medical imaging and radiology department]

Technological developments arising from research have affected the whole wide spectrum of medical endeavor and have made a very significant impact on clinical practice and especially on imaging sciences. Ultrasonography brought spectacular advances, but CT and MRI became important landmark techniques. A further important development, which greatly increased the involvement of radiologists in direct patient management, was the growth of interventional and therapeutic techniques, called interventional radiology. Some statistics: approximately 155,000 patients per year including 19,000 CT Scans, 10,000 MRI exams, 21,000 ultrasound examinations and 1,000 therapeutic procedures. Some research activities: CT quantification of pulmonary emphysema, respiratory mechanics, MR and CT angiography, antenatal diagnosis of congenital and genetic diseases of the fetus, quantification of portal haemodynamics, MR imaging of bile and pancreatic ducts, morphologic and functional imaging of the brain, radiology of bone trauma, MR characterization in hepatic lesions.

[Imaging of the female pelvis in adolescence]

The aim of this chapter is to familiarize the radiologists with the evolutive morphological features of the female genital apparatus, as it can be seen during the puberty, and to view the pathologies panel which may occur in ths period of life. This chapter is going to illustrate the morphological sonographic modifications from the childhood to the adolescence, emphasing the signs of pubertal maturation (uterus and ovaries shape, size and vascularization). Through clinical signs (delayed sexual maturation, primary or secondary amenorrhea, menstrual dysfunction, acute, cyclic, chronic pelvic pain and pelvic mass) the different pathologies are viewed, illustrating the important role of ultrasonography, but not an exclusive role.

Hepatic regenerating nodules: a mimic of recurrent cancer in children

BACKGROUND

Pseudometastatic lesions of the liver may be discovered incidentally in children previously treated for malignant tumour.

OBJECTIVE

To describe the radiological pattern of these lesions and to analyse their pathogenesis.

MATERIALS AND METHODS

Nine children, 2-12 years' old at the time of diagnosis, are described in this retrospective multicentre report. The primary tumours were: nephroblastoma (n = 2), neuroblastoma (n = 2), Ewing's tumour/PNET (n = 2), non-Hodgkin's lymphoma (n = 1), and osteosarcoma (n = 2), treated by surgery (8/9), chemotherapy (9/9), intensive chemotherapy and bone-marrow transplantation (5/9), and radiotherapy (7/9). Three children suffered veno-occlusive disease (VOD) during treatment. The hepatic assessment was performed by sonography (8/9), Doppler (7/9), multiphase spiral CT (8/9) and MRI (7/9).

RESULTS

Lesions were discovered 15 months to 16 years after completing treatment. CT was the most sensitive modality for diagnosis. Lesions were multiple in eight cases, measured 2-50 mm, and appeared hypervascular on the arterial phase of CT and/or MRI in every case. Metastases were excluded on the basis of histological verification (n = 2) and clinical and radiological follow-up.

CONCLUSION

Pseudometastatic hypervascular hepatic nodules can appear after treatment of a malignant tumour in children. The hypothesis of benign regenerative lesions secondary to treatment and/or VOD is considered.

Unusual findings in two cases of Langerhans' cell histiocytosis

We report unusual findings in two patients with Langerhans' cell histiocytosis (LCH), namely a cervical mass lesion with extensive destruction of the posterior elements of a cervical vertebra and gastrointestinal lesions as part of multisystem involvement. The aim of our report is threefold. Firstly, LCH can be responsible for osteolysis of the vertebral posterior arches, with or without involvement of the vertebral body, and should be included in the differential diagnoses of cervical mass lesions. Secondly, in a patient with confirmed LCH and additional protein-losing enteropathy, gastrointestinal involvement should be considered as a possibility since it is an important factor for establishing prognosis. Thirdly, LCH lesions can be very extensive and yet have a good response to therapy, whereas less spectacular lesions may not respond or respond only partially to therapy. Thus, an important factor in establishing prognosis is the presence of multisystem involvement at diagnosis, regardless of the extent of a lesion at a particular site.

Renal sinus hyperechogenicity in acute pyelonephritis: description and pathological correlation

This paper reports on the association between renal sinus hyperechogenicity and acute pyelonephritis. The medical records and imaging studies of 18 children displaying this pattern were retrospectively studied. Thickening of the renal pelvis and renal enlargement were the most frequent associated sonographic abnormalities. Further subtle findings can be found on sonography and colour/power Doppler. Their identification can help in the diagnostic approach to acute pyelonephritis and may obviate the need for other imaging modalities such as enhanced CT or 99mTc-DMSA scintigraphy. Renal sinus hyperechogenicity was also identified in a parallel study performed in female rabbits with experimental pyelonephritis and was shown, histologically, to be related to exudates of fibrin and polymorphonuclear leukocytes, interstitial oedema and micro-abscesses.

[Persistence of pulmonary lesions in a 6-year-old boy with type I Gaucher's disease treated by alglucerase since the age of 20 months]

BACKGROUND

Gaucher's disease is a serious disorder which becomes curable by bone marrow transplantation. Enzyme replacement therapy has permitted improvement in quality of life and has been shown to decrease the disease's progression.

OBSERVATION

A 6-year-old boy was treated by alglucerase (Ceredase) since the age of 20 months. He presented at that time a failure to thrive, pancytopenia, hepatosplenomegaly and bone involvement. The lung X-rays revealed a diffuse reticulonodular pattern. After 4 years and 5 months, there was an improvement of growth and hepatosplenomegaly, associated with hematological parameters and bone changes normalization. However, an important interstitial syndrome without clinical signs persisted.

CONCLUSION

In our patient it is impossible to note the difference between pulmonary disease from fibrotic origin and pulmonary involvement by Gaucher's cells accumulation.

Fetal endocardial fibroelastosis: ultrasonographic findings in two cases

EFE is a rare cardiac disorder with poor prognosis and uncertain cause. Primary and secondary forms have been described. Most authors consider that all EFE is secondary--a reactive process set off in the endocardium by stress on the myocardium. We report two cases representing the primary dilated form and the secondary contracted form. The dilated form was associated with intracavitary thrombus of the left ventricle. In both cases, an unusual presence of subendocardial calcifications was noted. The ultrasonographic findings are discussed.

Disappearing suprarenal masses in fetuses and infants

This paper presents 12 infants (9 boys, 3 girls) in whom the diagnosis of a suprarenal mass (10 left, 2 bilateral) was made on antenatal sonography. All were otherwise healthy neonates who were born at term after a normal pregnancy, labor and delivery. The masses ranged from 1 to 3.5 cm in diameter on initial scans at gestational ages of 19-35 weeks. Eleven masses were hyperechoic and 4 of these contained small, well-defined cysts. The 12th was hypoechoic. Follow-up sonography showed complete disappearance of the mass antenatally in 1 case and postnatally by 4-6 months in 5 cases; there was marked diminution in the size of the mass by 2 months of age in 4 infants, by 4 months in 1 case and by 15 months in 1 case. Eleven were managed nonoperatively. Laparotomy (after disappearance of the mass) in the 12th case revealed only some fibrous tissue. The 11 echogenic masses resemble previously reported imaging findings in infants with histologically proven intra-abdominal sequestrated lung. Conservative management with careful sonographic follow-up should, therefore, be considered in otherwise healthy fetuses or neonates with these imaging findings. We are less certain what the hypoechoic mass represented.

Cordocentesis for rapid karyotype: 421 consecutive cases

Between October 1985 and December 1993, 421 patients underwent fetal blood sampling for rapid karyotyping (426 samplings, 5 twin pregnancies). The aim of the study was to evaluate cordocentesis in terms of results, complications and additional information in this specific indication especially in case of abnormal pregnancy sonogram. The fetal loss rate possibly related to fetal blood sampling was 1.9%. Abnormal sonograms represented 91% of rapid karyotype indications. Chromosomal abnormalities were found in 9.5% of abnormal sonograms and in 16.9% of fetal structural anomalies (37 cases). The commonest chromosomal abnormality was trisomy 21 (11 cases). In conclusion, cordocentesis is a safe and reliable method for rapid karyotyping although it is associated with more risks than in other indications (congenital infections). The high rate of chromosomal abnormalities pleaded for ultrasonographic screening in a population usually not investigated by cytogenetic studies.

Twin-twin transfusion syndrome--possible roles for Doppler ultrasound and amniocentesis

A 29-year-old woman was referred for suspicion of twin-twin transfusion syndrome (TTTS). Several ultrasonographic and neonatal criteria of TTTS were encountered in this twin pregnancy. The peculiar observations in this case were, firstly, the demonstration of superficial anastomosis by Doppler ultrasound and, secondly, that one single therapeutic amniocentesis could have been sufficient to partially correct the progression of the syndrome, as after amniocentesis it was no longer possible to demonstrate the vascular communication. This observation suggests that superficial anastomoses could also have a role in the genesis of TTTS. Their effect could be monitored by Doppler ultrasound and could be more easily corrected by therapeutic amniocentesis.

Experience of a single team of operators in 891 diagnostic funipunctures

OBJECTIVE

To assess the efficacy and safety of diagnostic funipuncture.

METHODS

Between October 1985 and November 1993, fetal circulation was accessed 891 times in 828 pregnancies. The technique was similar to that described in earlier studies. We did not make more than two attempts at the procedure in any session. Each procedure was recorded prospectively in a computerized data base. Data included information about indications, laboratory indices, gestational age, number of successful and failed punctures, duration of fetal bradycardia, duration of bleeding, ultrasonographic findings, follow-up of pregnancies, and perinatal outcome.

RESULTS

The most frequent indication was rapid karyotyping (48.9%), followed by risk of congenital infection (38.6%). The success rate of the method was high (98.6%). Most samples (97%) were pure fetal blood, undiluted by amniotic fluid. Transient bleeding was observed from the cord puncture site in 9.8% of the procedures. Sixty-three percent of prolonged bradycardia occurred in growth-retarded or congenitally malformed fetuses. Seven fetal and neonatal deaths (five pregnancies) occurred within 1 week after the funipuncture; the funipuncture indication was rapid karyotyping in four of these cases.

CONCLUSION

Funipuncture performed by operators trained in ultrasonic needle guidance is a safe and reliable procedure.

[Cordocentesis: experience in 391 initial samples]

The first diagnostic cordocentesis was performed in our unit in october 1985. Our 4-year experience is reported: 391 cordocentesis were performed in 360 patients during gestational weeks 14 to 42. The first attempt was successful in 90% of the procedures, 4 samplings failed, there were 4 fetal deaths within one week after diagnostic cordocentesis, one of them appears to be directly linked to the punction. A transient fetal bradycardia was observed in 9.9% of the cases, bleeding occurred in 19% of the cases. The indications for cordocentesis were: risk of fetal infection, karyotyping, hemopathy, search for paternity, assessment of fetal acid-base status, biochemical dosage. Our data confirm that cordocentesis is a safe and reliable diagnostic procedure providing guidelines for management of the pregnancy.

[The value of prenatal chromosomal diagnosis in cases of fetal abnormalities: results obtained in 468 pathological pregnancies]

The authors report the results of 468 foetal karyotypes performed on amniotic fluid or foetal blood samples after ultrasound discovery of foetal anomalies. A total of 46 chromosomal aberrations (10%) were detected. The rates of anomalies vary considerably according to the alarm sign; very high (greater than 30%) in cases of multiple malformations, foetal hydrops or foetal death, low (less than or equal to 2%) in cases of poly- or oligohydramnios and foetal growth retardation without detectable malformation. In addition to these chromosomal diagnoses, further investigations enabled in 9 cases the diagnosis of genetic autosomal recessive disorders. Our results which are comparable with those reported in the literature, demonstrate the importance of prenatal diagnosis in cases of pathological pregnancies, with regard to obstetrical and perinatal management as well as to genetic counseling.

Diagnostic cordocentesis: two years of experience

The first diagnostic cordocentesis was performed in our unit in October 1985, our 2-year experience is reported. 144 samplings were performed in 137 patients (139 fetuses - 2 patients had twin pregnancies) during gestational weeks 14 to 42. The first attempt was successful in 80% of the procedures, 4 samplings failed. There were no fetal deaths within 3 days after diagnostic cordocentesis, a transient fetal bradycardia was observed in 12.2% of the cases, bleeding occurred in 13.6% of the cases. The indications for cordocentesis were: risk of fetal infection, karyotyping, hemophilia A, alloimmunisation, search for paternity, assessment of fetal acid-base status. Our data confirm that cordocentesis is a safe and reliable diagnostic procedure providing guidelines for management of the pregnancy.

The sonographic evaluation of normal thymus in infants and children

Sonography has been used to evaluate 50 "asymptomatic" infants (aged from birth up to two years) with typical appearing thymus on chest X-ray. The ultrasonic features of the normal gland are described. Moreover, the contribution of ultrasound is illustrated by five cases of partially ectopic thymus and by one case of prominent gland in a teenager. Ultrasound may help in differentiating normal gland from mediastinal masses by defining echogenicity, location and extension.

Pathological pregnancies. Results of amniotic fluid studies and fetal outcome

Late amniocenteses (greater than 20 weeks' gestation) were performed in 114 pregnancies with no a priori genetic risk, but referred because of abnormal clinical and/or ultrasound findings suggesting fetal malformations. Reasons for referral included polyhydramnios (51 cases), oligohydramnios (15 cases), fetal growth retardation (FGR) (16 cases) and abnormal fetal ultrasound findings excluding anencephaly (32 cases). In 42 of these cases, referral was motivated by a combination of the above abnormal findings. When polyhydramnios was the sole anomaly (25 cases), 5 fetuses were malformed (20%), abnormal fetal karyotype and/or elevated amniotic fluid alphafetoprotein (AFP) were demonstrated in 2 cases. Oligohydramnios was the sole anomaly in one case; the infant died of prematurity. Fetal growth retardation was the sole anomaly in 14 cases, 11 otherwise normal newborns were small for date, 2 died at birth and 1 was malformed (1/14, 7%). In this group all fetal karyotypes were normal and in 2 cases amniotic fluid AFP were increased. In the 32 pregnancies without abnormal amniotic fluid volume and/or FGR and with fetal malformation(s) suggested by ultrasound, all malformations except one (ovarian cyst possibly ruptured during birth) were confirmed at birth, amniotic fluid AFP was elevated, and/or karyotype was abnormal in 6 cases. In 42 pregnancies where more than one alarm sign was present, abnormal karyotype and/or elevated amniotic fluid AFP level were recorded in 21 of the 39 cases where amniocentesis was performed, 33 fetuses were malformed (79%) and 13 died in the perinatal period (31%). The high incidence of abnormal results of amniocentesis found in this survey of pathological pregnancies, particularly in those with multiple alarm signs, emphasizes the need for amniocentesis in these situations.