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R Chaoui

Publications and source records attributed to R Chaoui.

At least 55 records · Page 3Linked to original sources
PubMed2002

Prenatal diagnosis of ventriculocoronary arterial fistula in a fetus with hypoplastic left heart syndrome and aortic atresia.

In a fetus with a hypoplastic left heart syndrome detected at 26 weeks' gestation, a communication between the left ventricular cavity and the left coronary artery was detected using color Doppler. Bidirectional flow was demonstrated and the ventricle was shown to be filled via the fistula during diastole. After premature birth at 31 weeks and neonatal death, autopsy confirmed the findings. Because the association of a heart defect with ventriculocoronary communications worsens the neonatal prognosis, it should be ruled out in fetuses with hypoplastic left heart syndrome before parents are counseled.

Adult↗
PubMed2002

Marked splenomegaly in fetal cytomegalovirus infection: detection supported by three-dimensional power Doppler ultrasound.

An enlarged fetal spleen can be associated with fetal infection, anemia and different syndromes but its prenatal diagnosis is rare. We report on a diagnosis of splenomegaly at 32 weeks' gestation in a fetus which was found to be affected by cytomegalovirus infection. An enlarged spleen was suspected when the stomach was found to be displaced anteriorly and medially and the diagnosis was supported on visualization of the splenic vessels by color and three-dimensional power Doppler ultrasound. The patient had been referred because of fetal growth restriction and intracerebral anomalies and the additional finding of splenomegaly was highly suspicious for cytomegalovirus infection. This was confirmed by positive maternal serology and by neonatal virus excretion in urine. Retrospectively, examination of stored blood samples from 9 and 23 weeks' gestation revealed an early cytomegalovirus infection. Antenatal and neonatal magnetic resonance imaging examinations showed microcephaly, lissencephaly and the presence of microcalcifications. At the age of 9 months, the child suffers from severe neurological impairment and blindness due to severe optical atrophy. This case emphasizes that color Doppler and three-dimensional power Doppler ultrasound can facilitate the antenatal diagnosis of splenomegaly and can help to delineate the spleen from the similar-looking neighboring liver.

Adult↗
PubMed2002

Absent or hypoplastic thymus on ultrasound: a marker for deletion 22q11.2 in fetal cardiac defects.

OBJECTIVE: Congenital heart defects (CHD), particularly conotruncal anomalies, may be associated with deletion of chromosome 22q11.2. Thymic aplasia or hypoplasia is known to be a typical feature in this condition. We aimed to establish (i) the prevalence of del22q11.2 in fetal CHD and (ii) whether ultrasound assessment of an absent or hypoplastic fetal thymus helps in preselection of a group who are at high risk for this deletion. STUDY DESIGN: In fetuses (> 16 weeks) with CHD, karyotyping and fluorescence in situ hybridization for 22q11.2 were offered and the fetal thymus was evaluated sonographically. RESULTS: One hundred and forty-nine fetuses with CHD and normal karyotype were analyzed. Seventy-six fetuses had conotruncal anomalies. 22q11.2 deletion was present in 10 cases (6.7%), all of which had conotruncal anomalies (13.1%). Thymic hypoplasia or absence was suspected in 11 cases with conotruncal anomaly. Nine of these 11 had the deletion; two cases were false positive. One fetus with a normal-sized thymus had deletion of 22q11.2 (sensitivity 90%, specificity 98.5%, positive predictive value 81.8%, and negative predictive value 99.2%). By subtype of cardiac anomaly, there was deletion in four of six fetuses with interruption of the aortic arch, two of four with absent pulmonary valve syndrome, three of nine with truncus arteriosus and one of 11 cases of tetralogy of Fallot. Pulmonary atresia with ventricular septal defect (n = 7), right-sided aortic arch (n = 4), transposition of the great arteries (n = 14), double outlet right ventricle (n = 13) and other complex malpositions of the great vessels (n = 8) were not associated with the deletion. CONCLUSION: Thymic hypoplasia or aplasia may reliably be diagnosed during fetal echocardiography. The technique allows identification of a group at high risk for 22q11.2 deletion and is more specific and sensitive than by subtype of cardiac anomaly alone.

Chromosomes, Human, Pair 22↗
PubMed2002

Does fetal tracheal fluid flow during fetal breathing movements change before the onset of labour?

OBJECTIVE: To examine changes in intra-tracheal fluid flow parameters during fetal breathing movements throughout the second half of pregnancy in the normally developing human fetus. DESIGN: Prospective cross-sectional study. SETTING: Fetal medicine unit at the Charité University Hospital in Berlin. METHODS: Assessment of tracheal fluid flow was attempted in 340 healthy fetuses (GA 20-40 weeks) in which fetal breathing movements were seen by B-mode scan. Colour Doppler was applied to visualise the tracheal fluid flow, followed by spectral Doppler to record the velocity waveforms. The records of 53 fetuses divided into five gestational age groups (20-23, 24-27, 28-31, 32-35 and 36-40 weeks of gestation) containing 40 or more continuous breathing cycles (inspiration and expiration) were considered for analysis. Only regular breathing phases were examined and the volume obtained by integration of the tracheal fluid flow displaced during fetal breathing movements was calculated. RESULTS: The intra-tracheal flow volume moved during inspiration (Vi) and expiration (Ve) increased until 36 weeks of gestation after which there was a flattening until term. This suggests either a reduction of lung liquid production or a diminished lung liquid volume. The median difference between Vi and Ve was positive in the first four age groups and negative in the last one suggesting that, in mature fetuses, the effect of fetal breathing movements no longer results in an influx. CONCLUSIONS: Our data demonstrate a modification in fetal behaviour that manifests itself during the last four weeks before birth and has the potential to reduce lung liquid volume.

Body Fluids↗
PubMed2001

Reliability of prenatal sonographic lung biometry in the diagnosis of pulmonary hypoplasia.

OBJECTIVE: The purpose of the present study was to assess the value of biometric lung measurements for the diagnosis of severe fetal pulmonary hypoplasia by investigating whether a significant correlation between two-dimensional lung biometry measurements and autopsy findings could be established. METHODS: This was a prospective study carried out between 1995 and 1997. Nomograms for normal fetuses of the anterior-posterior and transverse inner thoracic diameters, which describe the growth and shape of the lung, were used as a basis for diagnosis of pulmonary hypoplasia in fetuses at high risk of developing the condition (the fetuses had bilateral renal agenesis or multicystic kidneys; chronic PROM <25 gestational weeks or hydrothorax). Pregnancy was terminated by abortion or intrauterine death in 29/43 high-risk fetuses and autopsies were performed. Only the 29 fetuses for which there were autopsy findings were included in the study. RESULTS: The best plane for diagnosing pulmonary hypoplasia was the four-chamber view. The diagnostic accuracy for this view as expressed by the sensitivity was 57% for the anterior-posterior diameter and 44% for the transverse diameter; as expressed by the specificity it was 42% for the anterior-posterior diameter and 50% for the transverse diameter. The results for the four-chamber view for the various high-risk conditions were as follows: for fetuses with chronic PROM we obtained sensitivities of 75% and 50% (anterior-posterior and transverse dimensions, respectively) and specificities of 80% and 60% (anterior-posterior and transverse dimensions, respectively). The sensitivities of lung biometry in fetuses with hydrothorax were 1% and 80% for the two diameters, but there was a low specificity. In fetuses with bilateral renal agenesis or multicystic kidneys we obtained sensitivities of 36% and 30% (anterior-posterior and transverse dimensions, respectively) and a specificity of 50% (anterior-posterior dimension). CONCLUSIONS: The present results show that two-dimensional lung biometry is not a suitable method for antenatal detection of pulmonary hypoplasia. However, in individual cases with high risk for pulmonary hypoplasia, lung biometry might prove to be an additional diagnostic parameter.

Autopsy↗
PubMed2001

Fetal autopsy: a review of recent developments.

OBJECTIVE: To analyze recent changes in fetal autopsy in response to developments in prenatal medicine. METHOD: During the period 1988 through 1997, 783 fetuses (75% induced abortions, 18% spontaneous abortions, and 7% stillbirths, all between the 12th and 40th week of gestation) with prenatally diagnosed congenital malformations and chromosomal aberrations were analyzed. We divided the autopsies into two periods: period A (1988-92, n=370) and period B (1993-97, n=413). All fetuses were analyzed before completion of 20 weeks of gestation. The malformations of the organ systems were presented according to their frequency for fetuses independent of the weeks of gestation. RESULTS: An autopsy was performed prior to the completion of 20 weeks of gestation for 24% of the fetuses in period A and 45% in period B (P<0.0001). The number of diagnosed congenital heart malformations increased from 16% in period A to 23% in period B. The number of congenital heart malformations before completion of 20 weeks of gestation was only 21% in period A as compared to 42% in period B. CONCLUSIONS: In period B, clinical questions were raised in a more concrete form and ultrasound images gave more detailed information than in period A. Access to prenatal findings prior to postmortem examination has helped investigators to develop a specific, clinically oriented, autopsy strategy based on the prenatal findings which makes it possible to diagnose very small malformations and to select sectional planes of special interest. The use of an interdisciplinary database is required for communication.

Abnormalities, Multiple↗
PubMed2001

Application of three-dimensional power Doppler ultrasound in prenatal diagnosis.

OBJECTIVE: To assess the fetal cardiovascular system using three-dimensional power Doppler ultrasound (3D-PDU) in normal and abnormal conditions during the second half of gestation. SUBJECTS: Forty-five normal fetuses and 87 selected pregnancies with different abnormalities involving the vascular system were examined. METHODS: The following regions of interest were assessed: placental, umbilical, abdominal, renal, pulmonary and intracranial vessels together with the heart and great arteries. Equipment used was a commercially available HDI-3000 and 5000 ultrasound system with integrated 3D-Color Power Angio software. Data acquisition was performed by the free-hand technique. Images were reconstructed online. In pathological cases, a maximum of three attempts of 3D reconstruction was allowed to obtain the information needed. RESULTS: Satisfactory visualization of the fetal vascular system using 3D-PDU could be achieved in normal pregnancies. The main difficulty during the learning curve was the optimization of the power Doppler image prior to 3D data acquisition. Despite good visualization conditions, the reconstruction of satisfactory images was only possible in 56 out of the 87 (64%) pregnancies with abnormal vascular anatomy. These were abnormalities of placenta and umbilical vessels (n = 26), intra-abdominal and intrathoracic anomalies (n = 12), renal malformations (n = 9), central nervous system (n = 4) and cardiac defects (n = 5). The main reasons for the lack of information were fetal position and movements, overlapping with signals from neighboring vessels as well as technical limitations of the online system. Details and figures of the potential field of interest in prenatal diagnosis are presented.

Cardiovascular System↗
PubMed2001

Fetus and uteroplacental unit: fast MR imaging with three-dimensional reconstruction and volumetry--feasibility study.

In 22 fetuses, three-dimensional reconstruction was performed on the basis of T2-weighted magnetic resonance (MR) data sets by using a surface-rendering technique. Fetuses and uteroplacental units were segmented manually; volumes were calculated automatically. Three-dimensional reconstruction and volumetry of the fetus and uteroplacental unit are feasible with MR data sets. MR estimates correlated closely with ultrasonographic fetal biometric estimates and birth weight.

Adult↗
PubMed2001

Longitudinal observation of deterioration of Doppler parameters, computerized cardiotocogram and clinical course in a fetus with growth restriction.

We report on a fetus with intrauterine growth restriction detected at 27 weeks' gestation, who was longitudinally followed up until delivery by cesarean section 33 days later (31 + 5 weeks) due to severe decelerations in CTG. Longitudinal Doppler assessment of the umbilical artery (UA), the middle cerebral artery (MCA) and the main branch of the right pulmonary artery (RPA), the ductus venosus (DV) and the left coronary artery was compared to clinical course and computerized CTG. At first presentation (day--33) increased resistance in both the UA and uterine arteries with bilateral notches was found. Absent enddiastolic flow (AED) in the UA was found at day--19 and reverse flow (RED) at day--11. The MCA showed a decreased pulsatility first at day--19 and again at day--11 together with RED in the UA. The RPA initially (day--33) showed increased PI which returned to normal values at day--19 but increased again at day--1, when the DV showed RED and the coronary arteries became visible. The DV was normal until day--11, then its PI began to increase together with occurence of RED in the UA, but reverse flow in the DV occurred only on the eve (day--1) of severe decelerations in CTG. Short-term variability in computerized CTG was stable at 6 to 7 ms, except for an intermediate drop to 4 ms at day--10. Maternal hypertension was found at day--19 and mild preeclampsia developed at day--12. A reduction of fetal movements was noticed at day--5. This report shows that at 29 weeks gestation despite detection of AED resp. RED in the UA a prolongation of pregnancy for 19 resp. 11 days is possible. In addition to abnormal CTG, late signs of fetal deterioration are reverse flow in the DV and visibility of the coronary arteries. The role of increased resistance in the main branches of the pulmonary arteries should be examined in the future.

Adult↗
PubMed2000

World experience of percutaneous ultrasound-guided balloon valvuloplasty in human fetuses with severe aortic valve obstruction.

Prenatal alleviation of severe fetal aortic valve obstructions by percutaneous ultrasound-guided balloon valvuloplasty has been performed to improve the fate of affected fetuses. The purpose of this study was to analyze the current world experience of these procedures in human fetuses. Data from 12 human fetuses were available for analysis. The mean gestational age at intervention was 29.2 weeks (range 27 to 33). The mean time period between initial presentation and intervention was 3.3 weeks (range 3 days to 9 weeks). Technically successful balloon valvuloplasties were achieved in 7 fetuses, none of whom had an atretic valve. Only 1 of these fetuses remains alive today. Of the 5 remaining technical failures, 1 patient with severe aortic stenosis underwent successful postnatal intervention and remains alive. Six patients who survived prenatal intervention died from cardiac dysfunction or at surgery in the first days or weeks after delivery. Four fetuses died early within 24 hours after the procedure, 1 from a bleeding complication, 2 from persistent bradycardias, and 1 at valvotomy after emergency delivery. Thus, the early clinical experience of percutaneous ultrasound-guided fetal balloon valvuloplasty in human fetuses with severe aortic valve obstruction has been poor due to selection of severe cases, technical problems during the procedure, and high postnatal operative mortality in fetuses who survived gestation. Improved patient selection and technical modifications in interventional methods may hold promise to improve outcome in future cases.

Aortic Valve↗
PubMed2000

Differentiation between human fetal breathing patterns by investigation of breathing-related tracheal fluid flow velocity using Doppler sonography.

We report our results from the analysis of Doppler measurements of breathing-related fluid flow velocity waveforms in the trachea in human fetuses. Our aim was to determine whether, using the proposed method, reproducible patterns can be recognized over the latter half of gestation. Breathing-related tracheal fluid flow velocity of 47 normal fetuses at 20-39 weeks' gestation were analysed. Colour Doppler was used to document 'streaming' of fluid in the trachea, followed by spectral Doppler to record flow velocity waveforms. More than 40 (median 94; range 42-725) continuous breathing cycles (inspiration+expiration) were obtained in each case. Although breathing-related fetal tracheal fluid flow waveforms were found to be highly variable, we were able to distinguish by visual analysis between a regular and an irregular pattern. Among the regular patterns, we further differentiate between a regular symmetric (sinusoidal type) and a regular asymmetric (deep inspiration with expiratory flow retardation) pattern. The regular pattern occurred consistently in all age groups studied and there were no significant (p<0.05) differences in the occurrence rate of the regular symmetric and asymmetric pattern. The incidence of the regular pattern increased significantly (p<0.05) from 11.74+/-3.38% (mean +/- SEM) at 24-27 weeks to 20.72+/-1.75% at 28-31 weeks of gestation and remained constant thereafter. This study shows that the proposed method can provide detailed information on breathing-related tracheal fluid flow velocity as early as 20 weeks of gestation. The information that a regular symmetric pattern was observed throughout the second half of gestation is important. Hence, a higher standardization of on-going fetal breathing movements studies may be achieved by measuring breathing-related tracheal fluid flow velocity waveform parameters only during this pattern.

Body Fluids↗
PubMed2000

Pathologic correlation of sonographic echogenic foci in the fetal heart.

The goal of the current paper is to present, on the basis of six investigated fetal hearts, the pathological substrate of prenatally, sonographically diagnosed echogenic intramyocardial foci. The right ventricle, left ventricle, interventricular septum and papillary muscles of both ventricles of six hearts of the fetuses of high-risk pregnant women showing sonographically diagnosed intramyocardial echogenic foci were investigated. At termination of pregnancy all the women were between the 20th and the 24th week of gestation. Of the six cases, four were induced abortions and two were spontaneous abortions. For the control group we investigated the hearts of two fetuses without heart defects at the 22nd and 23rd week of gestation which had proven extracardial anomalies and a normal karyotype. Both cases were induced abortions which prenatally showed no echogenic cardiac foci. In all eight cases a prenatal karyotyping was performed. In the six cases with echogenic foci the location and number of the foci were determined both prenatally and by means of histologic sections; the size of the foci was measured as well. Histological staining was with routine haematoxylin-eosin; Masson-Goldner was used for connective tissue; Kossa for calcification; and Berlin blue for haemosiderin. Histologically, in all six cases, intramyocardial calcifications surrounded by fibrotic tissue were in: papillary muscle of the left ventricle in six cases; papillary muscle of the right ventricle in one case; and the subendocardial myocardium of the right ventricle in one case. Four cases had one, one case had two and one case had three calcified foci. Three cases had cardiac and two cases had extracardiac anomalies. Four cases had chromosome anomalies: two were trisomy 21, one trisomy 13 and one triploidy. The remaining two cases had a normal karyotype. No case showed pathological changes of the chordae tendinae, myocardial cell necrosis or inflammation. There were no patho-morphological differences between the intramyocardial calcifications of the papillary muscles in cases with chromosome anomalies and with normal karyotype. As the patho-morphological correlate of the sonographically diagnosed echogenic foci, histological investigation on all six fetal hearts showed coarse intramyocardial calcifications surrounded by myocardial fibrosis. Conventional histological methods gave no indication of the cause of the intramyocardial calcifications.

Abortion, Induced↗
PubMed2000

[Autopsy techniques in congenital heart defects. Influence of prenatal diagnosis on the planning and carrying out of autopsies].

As a result of the quality of prenatal ultrasound and the expanded experience of prenatal diagnosticians, it is possible to observe congenital heart malformations in increasingly greater detail and at an ever earlier stage of gestation [4]. Since it is on the basis of ultrasound findings that decisions to terminate pregnancies are made, it is of cardinal importance that after termination monitoring and confirmation of the prenatal diagnosis be carried out. This need can only be adequately met by autopsy. There are different methods for carrying out autopsies when there is suspicion of a congenital heart defect: a) the Anderson sequential segmental analysis as modified according to the Berlin method; b) use of a special autoptic method corresponding to the ultrasound findings, based on defining a preferred sectional plane; c) stereomicroscopically; or d) microscopically after embedding and preparation of serial microscopic sections. For the pathologist the consequence is that he has to adapt his autopsy method to the ultrasound findings and the age of the fetus. This enables him to determine an optimal, case-based autopsy strategy for each type of cardiac defect, which is essential for monitoring of the prenatal diagnosis. The present paper discusses the various autoptic methods used in cases of congenital heart malformations and the consequences for the pathologist of the continuing improvements in prenatal diagnostics.

Autopsy↗
PubMed2000

Prognostic significance of the pouch sign in fetuses with prenatally diagnosed esophageal atresia.

OBJECTIVE: Esophageal atresia may be diagnosed prenatally by ultrasonographic visualization of the blind-ending esophagus during fetal swallowing, which is referred to as the pouch sign. Our purpose was to determine whether this sign can be used to predict outcomes of affected fetuses. STUDY DESIGN: Four cases of esophageal atresia diagnosed in our center during the past 2 years were analyzed, in conjunction with 3 cases from published series. Ultrasonographic features of the pouch sign were categorized according to localization. RESULTS: In the neck pouch group (n = 3) 1 fetus died in utero and 1 died before a corrective operation could be undertaken. In the only fetus of this group to survive a staged repair was necessary because of a long atretic gap. Conversely, 3 of the 4 fetuses with a mediastinal pouch survived after a successful corrective operation, and primary repair was possible in all cases. CONCLUSIONS: The base of the proximal blind-ending esophagus can be clearly localized by means of ultrasonography. Our data suggest that a neck pouch may be associated with an adverse outcome. This information may be useful in counseling parents when esophageal atresia is diagnosed prenatally.

Esophageal Atresia↗