A. Carletti

Diagnosis of midline anomalies of the fetal brain with the three‐dimensional median view

To investigate the effectiveness of a simplified approach to the evaluation of the midline structures of the fetal brain using three‐dimensional (3D) ultrasound.

Prenatal diagnosis of open and closed spina bifida

To identify criteria useful for differentiating closed from open spina bifida antenatally.

Prenatal diagnosis and outcome of fetal posterior fossa fluid collections

To evaluate the accuracy of fetal imaging in differentiating between diagnoses involving posterior fossa fluid collections and to investigate the postnatal outcome of affected infants.

Prenatal diagnosis and outcome of partial agenesis and hypoplasia of the corpus callosum

To present antenatal sonographic findings and outcome of fetuses with hypoplasia or partial agenesis of the corpus callosum.

Prenatal diagnosis of cerebral lesions acquired in utero and with a late appearance

Although no precise figures are available, many congenital brain lesions arise from intrauterine disruption, frequently due to obstetric complications. The most common entities include intracranial hemorrhage, ischemic lesions, thrombosis of venous vessels and infections. Accurate prenatal diagnosis is possible in many of these cases. However, the findings may be subtle, particularly in the early stage of the disruptive process. Identification of these conditions requires therefore specific expertise, the combination of fetal neurosonography and magnetic resonance, and frequently there is a need for serial examinations. Targeted diagnostic imaging should be offered to obstetric patients with conditions predisposing to prenatal cerebral insults. Copyright

Difficult early sonographic diagnosis of absence of the fetal septum pellucidum.

Standard sonographic views of the brain obtained along the axial planes at mid‐gestation failed to identify absence of the septum pellucidum in two consecutive fetuses. It was presumably the close proximity of the walls of the lateral ventricles that generated an artifact resembling a normal cavum septi pellucidi. In one of these fetuses, septo‐optic dysplasia was confirmed by magnetic resonance demonstration of hypoplastic optic tracts. In the other fetus, isolated absence of the septum pellucidum was the final diagnosis. Standard axial scans are unreliable in predicting absence of the septum pellucidum in the mid‐trimester fetus when the lateral ventricles are normal in size. Copyright

Transient bowel ischaemia of the fetus.

Objective: To discover the different underlying conditions in 2 fetuses suffering from temporary bowel ischaemia. Methods: Abnormal bowel findings were detected using antenatal sonography. Results: The abnormal bowel findings disappeared postnatally. Transient ischaemia of the fetal bowel due to different causes has been advocated antenatally to explain the abnormal findings. When a normal blood supply to the bowel has been restored, either in utero or after birth, the abnormal findings disappear. Conclusions: Whenever gut dilatation is detected in a fetus at risk of bowel ischaemia the possibility of a transient functional finding must be considered.

OC160: Three‐dimensional ultrasonography is of limited value in diagnosing fetal spina bifida

provided clinically/prognostically important information in five cases and additional clinically irrelevant information in four. In the former group, the ultrasound diagnoses were: MCM + inferior vermis defect (MRI: isolated MCM), hydrocephalus + partial ACC (MRI: hydrocephalus), borderline ventriculomegaly + craniosynostosis + hemimegalencephaly (MRI: borderline ventriculomegaly), hypoplasia of the CC splenium (MRI: normal CC) and corpus callosum lipoma (MRI: + lissencephaly). Overall, the prognosis of the lesion was changed by the MRI examination in 5/92 cases (5.4%), while it increased the confidence of the diagnosis in 21/92 cases (22.8%). Conclusions: Expert neurosonography is able to reach a conclusive diagnosis in most CNS abnormalities referred to a tertiary center. The use of MRI as a second-line diagnostic procedure has a specific place in the evaluation of selected fetal anomalies, following specific queries raised by the expert neurosonologist.

OC14.01: Is there a role for magnetic resonance in addition to ultrasound in the prenatal diagnosis of fetal anomalies?

Objective: To assess whether the analysis of cyst content using mean grey value (MGV) discriminate ovarian endometriomas from other unilocular ovarian cysts. Methods: Stored 3D volumes from 54 unilocular ovarian cysts diagnosed in 50 premenopausal women (mean age: 36.9 years, range: 22 to 54 years) were analysed for calculating MGV from cyst content. No cyst with solid component or septations was included. MGV was calculated in all cases with VOCAL technique using 4D View software. B-Mode presumptive diagnosis based on examiner subjective impression was also recorded. Results: In 16 cases the cysts resolved spontaneously and were considered as hemorrhagic functional cysts. 38 cysts were surgically removed (6 simple cysts, 3 hemorrhagic cysts, 20 endometriomas, 6 mucinous cysts and 2 para-ovarian cysts). B-mode diagnosis were as follows: Simple cyst: 8 cases, hemorrhagic cyst: 17 cases, endometrioma: 24 cases, mucinous cyst: 4 cases and paraovarian cyst: one case. MGV was significantly higher in ovarian endometrioma as compared with all other kind of cysts (Table). ROC curve showed that a MGV cut-off > 15.566 had a 85% sensitivity and 76.5& specificity for diagnosing ovarian endometrioma (AUC: 0.831, 95% CI: 0.72 to 0.94). These figures were similar to that for B-mode diagnosis (sensitivity: 90%, specificity: 82.4%) (McNemar test: p = 1.000) Conclusion: MGV of cyst content is higher in ovarian endometrioma than in other unilocular ovarian cysts. Its diagnostic performance is similar than subjective examiner’s diagnosis.

OP11.01: Diagnosis of uterine congenital anomalies: 3D transvaginal sonography versus 2D‐3D saline infusion sonohysterography

Objectives: Twin–twin transfusion syndrome (TTTS) can be successfully treated by endoscopic laser ablation of communicating placental vessels, resulting in increased survival and decreased perinatal morbidity by delaying delivery in twin pregnancies in comparison to serial amniodrainages. Up to now experience in triplets has been limited, with only 16 cases reported in the literature. This study reports our experience with laser coagulation in triplet pregnancies with TTTS. Methods: Ten cases of triplet pregnancy with severe TTTS were treated with endoscopic laser ablation at our center. Seven of them were dichorionic and three cases were monochorionic. Perinatal outcome and follow-up was obtained in all cases. Results: Fetoscopic laser ablation was performed at a median gestational age of 19.6 (range 18–21) weeks. The median gestational age at delivery was 31 (range 27–33) weeks resulting in a median interval between intervention and delivery of 77 days (range 56–89). All three fetuses survived in four cases which were all dichorionic. At least two fetuses survived in eight pregnancies. In one dichorionic and one monochorionic pregnancy PPROM and miscarriage occurred. Conclusions: Endoscopic laser ablation is an effective treatment in triplet pregnancies with severe TTTS. However, the risk for severely premature delivery is higher than in affected twin pregnancies.