Antenatal visualization of the caudo-thalamic groove at expert fetal neurosonography.

OBJECTIVE: to describe the normal features of the caudo-thalamic groove at antenatal brain ultrasound in a group of structurally normal fetuses at third trimester and to report a small series of cases with abnormal appearance of the caudothalamic groove at antenatal brain ultrasound. METHODS: This was an observational study conducted at two referral Fetal Medicine units. A non-consecutive cohort of pregnant women with a singleton non anomalous pregnancy were prospectively recruited and underwent 3D ultrasound of the fetal brain at 28-32 weeks. At offline analysis the ultrasound volumes were adjusted in the multiplanar mode according to a standardized methodology, until the caudothalamic groove was visible on the parasagittal plane. To evaluate the inter-observer agreement, two operators were independently asked to indicate if the caudothalamic groove was visible unilaterally or bilaterally on each volume. The digital archives of the two Centres were also retrospectively searched to retrieve cases with abnormal findings at the level of the caudothalamic groove at antenatal brain ultrasound which were postnatally confirmed. RESULTS: 180 non-consecutive cases fulfilling the inclusion criteria were prospectively included. At offline analysis of the 3D US volumes the caudo-thalamic groove was identified on the parasagittal plane by both operators at least unilaterally in 176 cases (97.8%) and bilaterally in 174 cases (96.6%). The K-coefficient for the agreement between the two independent operators in recognizing the caudo-thalamic groove was 0.89 and 0.83 on one and both hemispheres respectively. At the retrospective search of our archives 5 cases with abnormal appearance of the groove at antenatal brain ultrasound (2 haemorrhage and 3 cyst) were found. CONCLUSION: Our study has demonstrated that the caudo-thalamic groove is consistently seen among normal fetuses at third trimester submitted to multiplanar neurosonography and that abnormal findings at this level may be antenatally detected. This article is protected by copyright. All rights reserved.

Prediction of persistent occiput posterior position by sonographic assessment of fetal head attitude at start of second stage of labor: prospective study.

OBJECTIVES: To evaluate the relationship between the attitude of the fetal head quantified by means of the chin-to-chest angle (CCA) in fetuses in occiput posterior (OP) position at the beginning of the second stage of labor, and persistent OP position at birth. METHODS: This was a single-center, prospective observational study conducted at the University Hospital of Parma, Parma, Italy. We included singleton pregnancies at term with fetuses in the OP position at the beginning of the second stage of labor. The fetal head position, station by means of angle of progression and head-to-perineum distance, and attitude by means of CCA were assessed using transabdominal or transperineal ultrasound. The primary outcome was persistent OP position at birth. RESULTS: Between January and July 2022, 76 women were included in the study. There were 48 (63.2%) spontaneous rotations of the fetal head and spontaneous vaginal delivery occurred in all. Among the 28 (36.8%) fetuses that did not rotate spontaneously into an occiput anterior position, eight (28.6%) had a spontaneous vaginal delivery, while operative vaginal delivery and Cesarean delivery was performed in 11 (39.3%) and nine (32.1%) cases, respectively. Multivariable logistic regression analysis showed that the CCA (adjusted odds ratio (aOR), 2.15 (95% CI, 1.22-3.78); P = 0.008) and nulliparity (aOR, 0.20 (95% CI, 0.06-0.76); P = 0.02) were associated independently with persistent OP position at birth. Moreover, the CCA showed an area under the receiver-operating-characteristics curve of 0.69 (95% CI, 0.56-0.82); P = 0.005) for the prediction of persistent OP position. The optimal cut-off value of the CCA was 36.5°, and was associated with a sensitivity of 0.82 (95% CI, 0.63-0.94), specificity of 0.50 (95% CI, 0.35-0.65), positive predictive value of 0.49 (95% CI, 0.34-0.64), negative predictive value of 0.83 (95% CI, 0.64-0.94), positive likelihood ratio of 1.64 (95% CI, 1.18-2.29) and negative likelihood ratio of 0.36 (95% CI, 0.15-0.83). CONCLUSIONS: Our data show that, within a population of women with fetal OP position at the beginning of the second stage of labor, the sonographic fetal head attitude measured by means of the CCA might help in the identification of fetuses at risk of persistent OP position. Such findings can be useful for patient counseling when OP position is diagnosed at full cervical dilatation. Further studies should investigate if the CCA might select patients who may benefit from manual rotation of the fetal head. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Normal and abnormal appearance of fetal ganglionic eminence on second-trimester three-dimensional ultrasound.

OBJECTIVES: To describe the appearance and size of the ganglionic eminence (GE) in normal fetuses on midtrimester three-dimensional (3D) neurosonography and to report on the association between GE alterations (cavitation or enlargement) and malformation of cortical development (MCD). METHODS: This was a prospective multicenter cohort study of normal fetuses and a retrospective analysis of pathological cases with MCD. From January 2022 to June 2022, patients attending our tertiary centers for an expert fetal brain scan were recruited for the purpose of the study. A 3D volume of the fetal head, starting from the sagittal plane, was acquired in apparently normal fetuses using a transabdominal or transvaginal approach. Stored volume datasets were then evaluated independently by two expert operators. Two measurements (longitudinal diameter and transverse diameter) of the GE in the coronal view were obtained twice by each operator. Intra- and interobserver measurement variation was calculated. Reference ranges for GE measurements were calculated in the normal population. A previously stored volume dataset of 60 cases with MCD was also analyzed independently by the two operators using the same method in order to assess if GE abnormalities (cavitation or enlargement) were present. Postnatal follow-up was obtained in all cases. RESULTS: In the study period, 160 normal fetuses between 19 and 22 weeks of gestation were included in the study. The GE was visible in the coronal plane on 3D neurosonography in 144 (90%) cases and was not clearly visible in the remaining 16 (10%) cases. The intra- and interobserver agreement was almost perfect for the longitudinal diameter, with an intraclass correlation coefficient (ICC) of 0.90 (95% CI, 0.83-0.93) and 0.90 (95% CI, 0.86-0.92), respectively, and substantial for the transverse diameter, with an ICC of 0.80 (95% CI, 0.70-0.87) and 0.64 (95% CI, 0.53-0.72), respectively. A retrospective analysis of 50 cases with MCD in the second trimester showed that GE enlargement was present in 12 cases and GE cavitation was present in four cases. CONCLUSIONS: Systematic assessment of the GE in fetuses at 19-22 weeks of gestation is feasible on 3D neurosonography, with good reproducibility in normal cases. Cavitation or enlargement of the GE can be demonstrated in fetuses with MCD. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Mode of delivery and peripartum outcome in women with heart disease according to the ESC guidelines: an Italian multicenter study.

INTRODUCTION: The European Society of Cardiology (ESC) guidelines (GL) provide indications on the mode of delivery in women with heart disease. However available data suggests that the rate of Cesarean Delivery (CD) is high and widely variable among such patients. In this study, we aimed to investigate the degree of adherence to the ESC recommendations among women delivering in four tertiary maternity services in Italy and how this affects the maternal and neonatal outcomes. MATERIAL AND METHODS: Retrospective multicenter cohort study including pregnant women with heart disease who gave birth between January 2014 and July 2020. Composite adverse maternal outcome (CAM) was defined by the occurrence of one or more of the following: major postpartum hemorrhage, thrombo-embolic or ischemic event, de novo arrhythmia, heart failure, endocarditis, aortic dissection, need for re-surgery, sepsis, maternal death. Composite Adverse Neonatal outcome (CAN) was defined as cord arterial pH <7.00, APGAR <7 at 5 min, admission to the intensive care unit, and neonatal death. We compared the incidence of CAM and CAN between the cases with planned delivery in accordance (group "ESC consistent") or in disagreement (group "ESC not consistent") with the ESC GL. RESULTS: Overall, 175 women and 181 liveborn were included. A higher frequency of CAN was found when delivery was not planned accordingly to the ESC guidelines [("ESC consistent" 9/124 (7.2%) vs "ESC not consistent" 13/57 (22.8%) p = 0.002 OR 3.74 (CI 95% 1.49-9.74) , while the occurrence of CAM was comparable between the two groups. At logistic regression analysis, the gestational age at delivery was the only parameter independently associated with the occurrence of CAN (p = 0.006). CONCLUSION: Among pregnant women with heart disease, deviating from the ESC guidelines scheduling cesarean delivery does not seem to improve maternal outcomes and it is associated with worse perinatal outcomes, mainly due to lower gestational age at birth.

Uterine artery Doppler in early labor and perinatal outcome in low-risk term pregnancy: prospective multicenter study.

OBJECTIVE: The prediction of adverse perinatal outcomes in low-risk pregnancies is poor, mainly owing to the lack of reliable biomarkers. Uterine artery (UtA) Doppler is closely associated with placental function and may facilitate the peripartum detection of subclinical placental insufficiency. The objective of this study was to evaluate the association of mean UtA pulsatility index (PI) measured in early labor with obstetric intervention for suspected intrapartum fetal compromise and adverse perinatal outcome in uncomplicated singleton term pregnancies. METHODS: This was a prospective multicenter observational study conducted across four tertiary maternity units. Low-risk term pregnancies with spontaneous onset of labor were included. The mean UtA-PI was recorded between uterine contractions in women admitted for early labor and converted into multiples of the median (MoM). The primary outcome of the study was the occurrence of obstetric intervention, i.e. Cesarean section or instrumental delivery, for suspected intrapartum fetal compromise. Secondary outcomes were the occurrence of adverse perinatal outcomes, including 5-min Apgar score < 7, low cord arterial pH, raised cord arterial base excess, admission to the neonatal intensive care unit (NICU) and postnatal diagnosis of small-for-gestational-age fetus. Composite adverse perinatal outcome was defined as the occurrence of at least one of the following: acidemia in the umbilical artery, defined as pH < 7.10 and/or base excess > 12 mmol/L, 5-min Apgar score < 7 or admission to the NICU. RESULTS: Overall, 804 women were included, of whom 40 (5.0%) had abnormal mean UtA-PI MoM. Women who had an obstetric intervention for suspected intrapartum fetal compromise were more frequently nulliparous (72.2% vs 53.6%; P = 0.008), had a higher frequency of increased mean UtA-PI MoM (13.0% vs 4.4%; P = 0.005) and had a longer duration of labor (456 ± 221 vs 371 ± 192 min; P = 0.01). On logistic regression analysis, only increased mean UtA-PI MoM (adjusted odds ratio (aOR), 3.48 (95% CI, 1.43-8.47); P = 0.006) and parity (aOR, 0.45 (95% CI, 0.24-0.86); P = 0.015) were independently associated with obstetric intervention for suspected intrapartum fetal compromise. Increased mean UtA-PI MoM was associated with a sensitivity of 0.13 (95% CI, 0.05-0.25), specificity of 0.96 (95% CI, 0.94-0.97), positive predictive value of 0.18 (95% CI, 0.07-0.33), negative predictive value of 0.94 (95% CI, 0.92-0.95), positive likelihood ratio of 2.95 (95% CI, 1.37-6.35) and negative likelihood ratio of 0.91 (95% CI, 0.82-1.01) for obstetric intervention for suspected intrapartum fetal compromise. Pregnancies with increased mean UtA-PI MoM also showed a higher incidence of birth weight < 10th percentile (20.0% vs 6.7%; P = 0.002), NICU admission (7.5% vs 1.2%; P = 0.001) and composite adverse perinatal outcome (15.0% vs 5.1%; P = 0.008). CONCLUSION: Our study, conducted in a cohort of low-risk term pregnancies enrolled in early spontaneous labor, showed an independent association between increased mean UtA-PI and obstetric intervention for suspected intrapartum fetal compromise, albeit with moderate capacity to rule in, and poor capacity to rule out, this condition. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Role of fetal head-circumference-to-maternal-height ratio in predicting Cesarean section for labor dystocia: prospective multicenter study.

OBJECTIVE: To evaluate the relationship between the fetal head-circumference-to-maternal-height (HC/MH) ratio measured shortly before delivery and the occurrence of Cesarean section (CS) for labor dystocia. METHODS: This was a multicenter prospective cohort study involving four tertiary maternity hospitals. An unselected cohort of women with a singleton fetus in cephalic presentation, at a gestational age beyond 36 + 0 weeks and without any contraindication for vaginal delivery, was enrolled between September 2020 and November 2021. The MH and fetal HC were measured on admission of the patient to the labor ward. The primary outcome of the study was the performance of the HC/MH ratio in the prediction of CS for labor dystocia. Women who underwent CS for any indication other than failed labor progression, including fetal distress, were excluded from the final analysis. RESULTS: A total of 783 women were included in the study. Vaginal delivery occurred in 744 (95.0%) women and CS for labor dystocia in 39 (5.0%). CS for labor dystocia was associated with shorter MH (mean ± SD, 160.4 ± 6.6 vs 164.5 ± 6.3 cm; P < 0.001), larger fetal HC (339.6 ± 9.5 vs 330.7 ± 13.0 mm; P < 0.001) and a higher HC/MH ratio (2.12 ± 0.11 vs 2.01 ± 0.10; P < 0.001) compared with vaginal delivery. Multivariate logistic regression analysis showed that the HC/MH ratio was associated independently with CS for labor dystocia (adjusted odds ratio, 2.65 (95% CI, 1.85-3.79); P < 0.001). The HC/MH ratio had an area under the receiver-operating-characteristics curve of 0.77 and an optimal cut-off value for discriminating between vaginal delivery and CS for labor dystocia of 2.09, which was associated with a sensitivity of 0.62 (95% CI, 0.45-0.77), specificity of 0.79 (95% CI, 0.76-0.82), positive predictive value of 0.13 (95% CI, 0.09-0.19) and negative predictive value of 0.98 (95% CI, 0.96-0.99). CONCLUSIONS: In a large cohort of unselected pregnancies, the HC/MH ratio performed better than did fetal HC and MH alone in identifying those cases that will undergo CS for labor dystocia, albeit with moderate predictive value. The HC/MH ratio could assist in the evaluation of women at risk for CS for labor dystocia. © 2022 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Incidence, clinical features and perinatal outcome in anomalous fetuses with late-onset growth restriction: cohort study.

OBJECTIVE: To describe the incidence, clinical features and perinatal outcome of late-onset fetal growth restriction (FGR) associated with genetic syndrome or aneuploidy, structural malformation or congenital infection. METHODS: This was a retrospective multicenter cohort study of patients who attended one of four tertiary maternity hospitals in Italy. We included consecutive singleton pregnancies between 32 + 0 and 36 + 6 weeks' gestation with either fetal abdominal circumference (AC) or estimated fetal weight < 10th percentile for gestational age or a reduction in AC of > 50 percentiles from the measurement at an ultrasound scan performed between 18 and 32 weeks. The study group consisted of pregnancies with late-onset FGR and a genetic syndrome or aneuploidy, structural malformation or congenital infection (anomalous late-onset FGR). The presence of congenital anomalies was ascertained postnatally in neonates with abnormal findings on antenatal investigation or detected after birth. The control group consisted of pregnancies with structurally and genetically normal fetuses with late-onset FGR. Composite adverse perinatal outcome was defined as the presence of at least one of stillbirth, 5-min Apgar score < 7, admission to the neonatal intensive care unit (NICU), need for respiratory support at birth, neonatal jaundice and neonatal hypoglycemia. The primary aims of the study were to assess the incidence and clinical features of anomalous late-onset FGR, and to compare the perinatal outcome of such cases with that of fetuses with non-anomalous late-onset FGR. RESULTS: Overall, 1246 pregnancies complicated by late-onset FGR were included in the study, of which 120 (9.6%) were allocated to the anomalous late-onset FGR group. Of these, 11 (9.2%) had a genetic syndrome or aneuploidy, 105 (87.5%) had an isolated structural malformation, and four (3.3%) had a congenital infection. The most frequent structural defects associated with late-onset anomalous FGR were genitourinary malformations (28/105 (26.7%)) and limb malformation (21/105 (20.0%)). Compared with the non-anomalous late-onset FGR group, fetuses with anomalous late-onset FGR had an increased incidence of composite adverse perinatal outcome (35.9% vs 58.3%; P < 0.01). Newborns with anomalous, compared to those with non-anomalous, late-onset FGR showed a higher frequency of need for respiratory support at birth (25.8% vs 9.0%; P < 0.01), intubation (10.0% vs 1.1%; P < 0.01), NICU admission (43.3% vs 22.6%; P < 0.01) and longer hospital stay (median, 24 days (range, 4-250 days) vs 11 days (range, 2-59 days); P < 0.01). CONCLUSIONS: Most pregnancies complicated by anomalous late-onset FGR have structural malformations rather than genetic abnormality or infection. Fetuses with anomalous late-onset FGR have an increased incidence of complications at birth and NICU admission and a longer hospital stay compared with fetuses with isolated late-onset FGR. © 2022 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Expert opinion: Stepwise ultrasound assessment of suspected placenta accreta spectrum using 2D, Doppler and 3D imaging.

Placenta Accreta Spectrum (PAS) describes a spectrum of conditions ranging from 'sticky' placenta to placenta accreta, increta and percreta-each describing progressively deeper invasion into the uterus. It is a major contributor to maternal and perinatal morbidity particularly where clinical facilities are not immediately available. Hence accurate diagnosis is important in determining timing and place of delivery, and logistical arrangements of the clinical team and specialties. Although many different ultrasound features have been described, their relationship to the final operative diagnosis remains variably described. Ultrasound manufactures have developed new imaging techniques particularly in relation to Doppler and 3D processing techniques. We describe a standardized imaging approach employing new ultrasound modalities matched to the attributes unique to invasive placenta. The '3V' system describes the stages of placental invasion: namely low-flow Doppler techniques to delineate the vascular anatomy of the placenta and delineating its interface with the myometrium, and 3D 'context preserving' post processing technologies defining the placental interface with maternal structures (vesicular invasion and visceral extension). Used together with well characterized 2D imaging signs, we describe pictorially by reference to clinical cases how this standardized methodology allows new insights into the ultrasound diagnosis of PAS.

Ultrasound prediction of adverse perinatal outcome at diagnosis of late-onset fetal growth restriction.

OBJECTIVE: To evaluate the relationship between Doppler and biometric ultrasound parameters measured at diagnosis and perinatal adverse outcome in a cohort of late-onset growth-restricted (FGR) fetuses. METHODS: This was a multicenter retrospective study of data obtained between 2014 and 2019 including non-anomalous singleton pregnancies complicated by late-onset FGR (≥ 32 weeks), which was defined either as abdominal circumference (AC) or estimated fetal weight (EFW) < 10th percentile for gestational age or as reduction of the longitudinal growth of AC by over 50 percentiles compared to ultrasound scan performed between 18 and 32 weeks of gestation. We evaluated the association between sonographic findings at diagnosis of FGR and composite adverse perinatal outcome (CAPO), defined as stillbirth or at least two of the following: obstetric intervention due to intrapartum fetal distress, neonatal acidemia, birth weight < 3rd percentile and transfer to the neonatal intensive care unit (NICU). RESULTS: Overall, 468 cases with complete biometric and umbilical, fetal middle cerebral and uterine artery (UtA) Doppler data were included, of which 53 (11.3%) had CAPO. On logistic regression analysis, only EFW percentile was associated independently with CAPO (P = 0.01) and NICU admission (P < 0.01), while the mean UtA pulsatility index (PI) multiples of the median (MoM) > 95th percentile at diagnosis was associated independently with obstetric intervention due to intrapartum fetal distress (P = 0.01). The model including baseline pregnancy characteristics and the EFW percentile was associated with an area under the receiver-operating-characteristics curve of 0.889 (95% CI, 0.813-0.966) for CAPO (P < 0.001). A cut-off value for EFW corresponding to the 3.95th percentile was found to discriminate between cases with and those without CAPO, yielding a sensitivity of 58.5% (95% CI, 44.1-71.9%), specificity of 69.6% (95% CI, 65.0-74.0%), positive predictive value of 19.8% (95% CI, 13.8-26.8%) and negative predictive value of 92.9% (95% CI, 89.5-95.5%). CONCLUSIONS: Retrospective data from a large cohort of late-onset FGR fetuses showed that EFW at diagnosis is the only sonographic parameter associated independently with the occurrence of CAPO, while mean UtA-PI MoM > 95th percentile at diagnosis is associated independently with intrapartum distress leading to obstetric intervention. © 2021 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Novel artificial intelligence approach for automatic differentiation of fetal occiput anterior and non-occiput anterior positions during labor.

OBJECTIVES: To describe a newly developed machine-learning (ML) algorithm for the automatic recognition of fetal head position using transperineal ultrasound (TPU) during the second stage of labor and to describe its performance in differentiating between occiput anterior (OA) and non-OA positions. METHODS: This was a prospective cohort study including singleton term (> 37 weeks of gestation) pregnancies in the second stage of labor, with a non-anomalous fetus in cephalic presentation. Transabdominal ultrasound was performed to determine whether the fetal head position was OA or non-OA. For each case, one sonographic image of the fetal head was then acquired in an axial plane using TPU and saved for later offline analysis. Using the transabdominal sonographic diagnosis as the gold standard, a ML algorithm based on a pattern-recognition feed-forward neural network was trained on the TPU images to discriminate between OA and non-OA positions. In the training phase, the model tuned its parameters to approximate the training data (i.e. the training dataset) such that it would identify correctly the fetal head position, by exploiting geometric, morphological and intensity-based features of the images. In the testing phase, the algorithm was blinded to the occiput position as determined by transabdominal ultrasound. Using the test dataset, the ability of the ML algorithm to differentiate OA from non-OA fetal positions was assessed in terms of diagnostic accuracy. The F1 -score and precision-recall area under the curve (PR-AUC) were calculated to assess the algorithm's performance. Cohen's kappa (κ) was calculated to evaluate the agreement between the algorithm and the gold standard. RESULTS: Over a period of 24 months (February 2018 to January 2020), at 15 maternity hospitals affiliated to the International Study group on Labor ANd Delivery Sonography (ISLANDS), we enrolled into the study 1219 women in the second stage of labor. On the basis of transabdominal ultrasound, they were classified as OA (n = 801 (65.7%)) or non-OA (n = 418 (34.3%)). From the entire cohort (OA and non-OA), approximately 70% (n = 824) of the patients were assigned randomly to the training dataset and the rest (n = 395) were used as the test dataset. The ML-based algorithm correctly classified the fetal occiput position in 90.4% (357/395) of the test dataset, including 224/246 with OA (91.1%) and 133/149 with non-OA (89.3%) fetal head position. Evaluation of the algorithm's performance gave an F1 -score of 88.7% and a PR-AUC of 85.4%. The algorithm showed a balanced performance in the recognition of both OA and non-OA positions. The robustness of the algorithm was confirmed by high agreement with the gold standard (κ = 0.81; P < 0.0001). CONCLUSIONS: This newly developed ML-based algorithm for the automatic assessment of fetal head position using TPU can differentiate accurately, in most cases, between OA and non-OA positions in the second stage of labor. This algorithm has the potential to support not only obstetricians but also midwives and accoucheurs in the clinical use of TPU to determine fetal occiput position in the labor ward. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.