Rabih Chaoui

Three‐dimensional (3D) and 4D color Doppler fetal echocardiography using spatio‐temporal image correlation (STIC)

Color Doppler echocardiography is used to visualize three transverse planes: the four‐chamber, five‐chamber, and three vessels and trachea views. Color Doppler spatio‐temporal image correlation (STIC) is a new three‐dimensional (3D) technique allowing the acquisition of a volume of data from the fetal heart that is displayed as a cineloop of a single cardiac cycle. The aim of the study was to examine the potential of color Doppler STIC to evaluate normal and abnormal fetal hearts.

Assessment of intracranial translucency (IT) in the detection of spina bifida at the 11–13-week scan

Prenatal diagnosis of open spina bifida is carried out by ultrasound examination in the second trimester of pregnancy. The diagnosis is suspected by the presence of a ‘lemon‐shaped’ head and a ‘banana‐shaped’ cerebellum, thought to be consequences of caudal displacement of the hindbrain. The aim of the study was to determine whether in fetuses with spina bifida this displacement of the brain is evident from the first trimester of pregnancy.

Three-dimensional ultrasound with maximal mode rendering: a novel technique for the diagnosis of bilateral or unilateral absence or hypoplasia of nasal bones in second-trimester screening for Down syndrome.

Three‐dimensional (3D) ultrasound of the fetal face with maximal mode rendering allows accurate visualization of the bony face and the distinct demonstration of both nasal bones in second‐trimester fetuses. The aim of this study was to analyze the feasibility of assessing nasal bones spatially on prenatal ultrasound in second‐ and third‐trimester fetuses with present and absent nasal bones.

Right aortic arch with vascular ring and aberrant left subclavian artery: prenatal diagnosis assisted by three‐dimensional power Doppler ultrasound

The prenatal detection of a right-sided aortic arch achieved mainly by targeted visualization of the threevessel and three vessels and trachea (3VT) view, with or without color Doppler, has been discussed recently in this journal1–4. Two typical forms of a right aortic arch can be distinguished5,6. In one condition a vascular ring is found around the trachea, the so-called U-sign prenatally (Figure 1)2,3. The trachea and esophagus are entrapped between the right aortic arch and the left ductus arteriosus and this abnormality is often an isolated incidental finding prenatally2. In the other condition, both the aorta and ductus arteriosus lie to the right of the trachea without a vascular ring. This condition is very commonly associated with cardiac anomalies5. The branching pattern of the great vessels arising from the aortic arch in both conditions is of major interest in pediatric cardiology5,6. The right aortic arch without a vascular ring usually exhibits mirror image branching of the arteries with the left innominate (brachiocephalic) artery arising first followed by the right common carotid and right subclavian artery6. By contrast, the right aortic arch with vascular ring very often has an association with an aberrant left subclavian artery. The left common carotid arises first from the aortic arch, followed by the right common carotid, right subclavian artery, and finally a retroesophageal vessel segment from which the left subclavian artery arises and the ductus arteriosus connects. The retroesophageal (and retrotracheal) vessel segment is known as the diverticulum of Kommerell. In other words, the left subclavian artery is connected ventrally to the ductus arteriosus arising from the left pulmonary artery, and dorsally through the Kommerell’s diverticulum to the descending aorta. In postnatal life, after closure of the ductus arteriosus, blood enters the left subclavian artery via the descending aorta and Kommerell’s diverticulum4. Prenatal assessment of a right-sided aortic arch and its branching pattern requires scanning in such planes as a transverse 3VT view (Figure 1), oblique cephalad Left

Pulmonary arterial Doppler velocimetry in fetuses with lung hypoplasia.

OBJECTIVE The aim of the study was to examine Doppler flow velocity waveforms in the main stems of the pulmonary arteries in fetuses with autopsy-proven lung hypoplasia and to find out whether in these conditions typical patterns can be found. STUDY DESIGN Doppler spectra were derived from the main stem of the right or left pulmonary artery in fetuses at high-risk for lung-hypoplasia. The following Doppler parameters were analyzed and compared to reference ranges: peak systolic velocity, acceleration time, time velocity integral, end-systolic reverse flow, pulsatility index (PI). Pulmonary hypoplasia was found in nine cases at autopsy after termination of pregnancy (19-23 weeks). According to etiology, three groups were considered: (A) bilateral renal malformations (n=4), (B) congenital diaphragmatic hernia (n=2), and (C) miscellaneous malformations including heart defects (n=3). RESULTS The following Doppler parameters were found: normal values in end-systolic reversal flow in all cases, decreased peak systolic velocity and acceleration time in 3/9, decreased time velocity integral in 4/9 and increased pulsatility index in 6/9. Considering the etiology of pulmonary hypoplasia the pulsatility index was found to be the most sensitive, since all fetuses in groups A and B had an abnormal PI. CONCLUSIONS Human fetuses with renal malformations and diaphragmatic hernia associated with lung hypoplasia show as early as 19-23 weeks of gestation an abnormal Doppler spectrum in the main stems of the pulmonary arteries. Increased PI is the best parameter to detect flow abnormality in this condition. Since the Doppler spectrum depends on cardiac anatomy and function, PI in lung hypoplasia seems to be reliable only when cardiac defects are absent.

Three-dimensional sonographic description of the fetal frontal bones and metopic suture

To describe the morphology of the frontal bones and metopic suture at 9–34 weeks of gestation using three‐dimensional (3D) ultrasonography.

Three‐dimensional sonographic description of abnormal metopic suture in second‐ and third‐trimester fetuses

To describe patterns of abnormal development of the metopic suture in association with fetal malformations during the second and third trimesters of pregnancy.

Metopic suture in fetuses with Apert syndrome at 22-27 weeks of gestation

To examine the possible association of skull deformity and the development of the cranial sutures in fetuses with Apert syndrome.

Three-dimensional multiplanar time-motion ultrasound or anatomical M-mode of the fetal heart: a new technique in fetal echocardiography

To assess the application of a three‐dimensional multiplanar rendering technique for examination of the fetal heart.

Small biparietal diameter in fetuses with spina bifida on 11–13‐week and mid‐gestation ultrasound

To assess whether, at 11–13‐week and mid‐trimester ultrasound examinations, the biparietal diameter (BPD) in fetuses with open spina bifida is smaller than the reference range.