Intracranial Translucency Research Articles

Diagnostic Accuracy of Nuchal and Intracranial Translucency by Two-dimensional versus Three- dimensional Ultrasonography in Low-Risk Pregnancy

Diagnostic Accuracy of Nuchal and Intracranial Translucency by Two-dimensional versus Three- dimensional Ultrasonography in Low-Risk Pregnancy

Enlarged Intracranial Translucency, as a Potential Marker for Diagnosis of Joubert Syndrome during First-Trimester Screening: A Case Report

AbstractJoubert syndrome (JS) is a rare autosomal recessive neurodevelopmental disorder that is usually diagnosed late in pregnancy or postnatally based on a pathognomonic midbrain–hindbrain malformation seen on magnetic resonance imaging brain, which consists of the hypoplasia of the cerebellar vermis, thickened superior cerebellar peduncles, and a deepened interpeduncular fossa described as molar tooth sign. The recurrence rate of JS in the same family is high (25%). In the era of first-trimester anomaly scan, early diagnosis of fetal anomaly is of utmost importance. First-trimester screening or first-trimester scan that is performed from 11 to 13 weeks, 6 days plays an important role in early diagnosis of posterior fossa abnormalities like Blake's pouch cyst, Vermian hypoplasia, Dandy-Walker malformation, and JS and related disorders based on increased intracranial translucency thickness. Our case also shows that early diagnosis of JS can be done by an enlarged intracranial translucency.

Normal intracranial translucency values during first trimester gestation in regional south Indian population: Cross sectional study

Normal intracranial translucency values during first trimester gestation in regional south Indian population: Cross sectional study

First Trimester Ultrasound Detection of Fetal Central Nervous System Anomalies.

To evaluate the potential of the first-trimester ultrasound (US) features for the detection of central nervous system (CNS) anomalies. Methods/Methodology: This is a prospective one-center three-year study. Unselected singleton pregnant women were examined using an extended first-trimester anomaly scan (FTAS) that included the CNS assessment: the calvaria shape, the septum (falx cerebri), the aspect of the lateral ventricles, the presence of the third ventricle and aqueduct of Sylvius (AS) and the posterior brain morphometry: the fourth ventricle, namely intracranial translucency (IT), brain stem/brain stem-occipital bone ratio (BS/BSOB) and cisterna magna (CM). The spine and underlying skin were also evaluated. The cases were also followed during the second and third trimesters of pregnancy and at delivery. FTAS efficiency to detect major CNS abnormalities was calculated. We detected 17 cases with CNS major abnormalities in a population of 1943 first-trimester (FT) fetuses, including spina bifida with myelomeningocele, exencephaly-anencephaly, holoprosencephaly, hydrocephaly, cephalocele and Dandy-Walker malformation. The CNS features in the abnormal group are presented. In the second trimester (ST), we further diagnosed cases of corpus callosum agenesis, cerebellar hypoplasia, vein of Galen aneurysm and fetal infection features (ventriculomegaly, intraventricular bands, intraventricular cyst and hyperechoic foci), all declared normal at the FTAS. During the third trimester (TT) scan we identified a massive fetal cerebral haemorrhage absent at previous investigations. We report a detection rate of 72.7% of fetal brain anomalies in the FT using the proposed CNS parameters. The sensitivity of the examination protocol was 72.7%, and the specificity was 100%. A detailed FT CNS scan is feasible and efficient. The majority of cases of major CNS abnormalities can be detected early in pregnancy. The visualization rates of the CNS parameters in the FT are great with short, if any, additional investigation time. FT cerebral disorders such as haemorrhage or infections were missed in the FT even when an extended evaluation protocol was used.

Qualitative and quantitative study of fetal posterior fossa during the first trimester in a Chinese population

BackgroundTo establish the normal reference ranges for parameters related to the fetal posterior fossa in the first trimester (11 ~ 13+6 weeks of gestation) and to analyze the relationship between them and crown-rump length (CRL) among the Chinese population.MethodsSingleton pregnancies of 11 ~ 13+6 weeks (CRL:45 ~ 84 mm) with both parents from China were randomly selected from January 2021 to November 2021. The related parameters of the posterior fossa including cisterna magna (CM), intracranial translucency (IT), brain stem (BS), brain stem to the occipital bone (BSOB), and brain stem/brain stem to occipital bone (BS/BSOB) were evaluated and measured in nuchal translucency (NT) mid-sagittal section clearly by an experienced sonographer (operator 1). To assess the reproducibility of the measurements, we randomly selected 50 pregnant women. According to the blind method, operators 1 and 2 respectively screened and measured relevant parameters. In addition, operator 1 examined and measured relevant parameters again 2 h after the first.ResultsThis study included 1663 fetuses. All fetuses can clearly show the three spaces of the fetal posterior fossa. The ICCs (95% CI) of intra-operator reproducibility of CM, IT, BS, BSOB, BS/BSOB were 0.981 (0.952 ~ 0.991, P < 0.001), 0.929 (0.866 ~ 0.961, P < 0.001), 0.970 (0.946 ~ 0.983, P < 0.001), 0.991 (0.974 ~ 0.996, P < 0.001), 0.939 (0.892 ~ 0.965, P < 0.001), respectively; The ICCs (95% CI) of inter-operator reproducibility 0.926 (0.860 ~ 0.960, P < 0.001), 0.810 (-0.083 ~ 0.940, P < 0.001), 0.820 (0.645 ~ 0.904, P < 0.001), 0.804 (0.656 ~ 0.888, P < 0.001), 0.772 (0.599 ~ 0.871, P < 0.001), respectively. There was a linear correlation between CRL and the parameters related to the posterior fossa (CM, IT, BS, BSOB, BS/BSOB). CM (mm) = -1.698 + 0.532 × CRL (cm) (r = 0.829, P < 0.001); IT (mm) = 0.701 + 0.179 × CRL (cm) (r = 0.548, P < 0.001); BS (mm) = 0.403 + 0.349 × CRL (cm) (r = 0.716, P < 0.001); BSOB (mm) = -0.277 + 0.719 × CRL (cm) (r = 0.829, P < 0.001); BS/BSOB = 0.747—0.021 × CRL (cm) (r = 0.196, P < 0.001).ConclusionsQualitative and quantitative assessment of the fetal posterior fossa structure was feasible in the first trimester. We constructed the normal reference ranges of CM, IT, BS, BSOB, and BS/BSOB. Furthermore, CM, IT, BS, and BSOB were positively correlated with CRL, but BS/BSOB was negatively correlated with CRL.

OP05.01: Frontal intracranial translucency in first trimester ultrasound as an early sonographic marker of abnormal brain development

OP05.01: Frontal intracranial translucency in first trimester ultrasound as an early sonographic marker of abnormal brain development

DEVELOPMENT OF A NORMAL RANGE FOR FIRST TRIMESTER PREGNANCY INTRACRANIAL TRANSLUCENCY MEASUREMENTS

Intracranial translucency (IT) by ultrasound in the first trimester is used in screening for open spina bifida, which is predominantly seen in the second trimester morphology ultrasound. IT has been used in many countries, including Asian and European countries. The aim of this study is to generate an IT normal range and to correlate IT measurements and neurological system abnormalities identified during second trimester ultrasound scan. A retrospective cohort study was performed using 199 foetal records taken from nuchal translucency (NT) clinic, from 1 June 2016 to 30 November 2019. Intracranial translucency (IT) measurements were assessed using existing nuchal translucency (NT) images of the foetuses aged 11 weeks to 13 weeks and 6 days of gestational age, where the foetal measurements taken for this study were between 45 and 84 mm. Eighteen samples were excluded, leaving only 181 samples that met the set criteria were used to establish the IT normal range. Inclusion criteria for this study involved all pregnant women with singleton pregnancies who had undergone NT scan with gestational ages ranging from 11 to 13 + 6 days. Based on the normal range value created, a total of 144 samples were normal foetuses, while the other 37 foetuses had various ultrasound abnormalities in the second trimester of pregnancy with no open spina bifida found. The results obtained exhibit linearly increased IT measurements with increasing crown-rump length (CRL), gestational age (GA), and nuchal translucency (NT).

The importance of first trimester screening of cranial posterior fossa in predicting posterior fossa malformations which may be identified in the following weeks of gestation.

We aimed to investigate the value of posterior fossa ultrasonography measurements in predicting fetal posterior fossa anomaly at 11-14 weeks of gestation. The study was performed at Zeynep Kamil Women and Children's Diseases Training and Research Hospital. Measurements were made in two groups: the control group consisted of 328 fetuses with normal postnatal outcome and the study group consisted of 22 fetuses with enlarged 4th ventricle. In the study group, we questioned the value of intracranial translucency (IT) and brainstem (BS) measurements and the BS/brainstem-to-occipital bone (BSOB) ratio in order to predict possible posterior fossa anomalies that may be identified in advanced gestational weeks. The differences of ultrasonographic measurements between groups with p < 0.05 were considered statistically significant. IT value, BSOB value, and BS/BSOB ratio were determined as ultrasonographic variables in predicting normal development of the fetal posterior fossa, with cutoff values of 2.7, 5.1, and 0.3. Negative predictive values of these three measurements for posterior fossa abnormalities were 100%. There was no statistically significant difference between the three variables for other diagnostic accuracy values (specifities and positive predictive values) (p > 0.05). IT, BSOB, and BS/BSOB ratio can be used as ultrasonographic markers to predict the normal development of the fetal posterior fossa.

Design of Standard Value Intracranial Translucency of Fetus in Early Pregnancy Using Ultrasound

Design of Standard Value Intracranial Translucency of Fetus in Early Pregnancy Using Ultrasound

VP24.01: Early diagnosis of rhombencephalosynapsis: the limits of intracranial translucency at 11–13 weeks – a plea for an evaluation of the aqueduct of Sylvius

VP24.01: Early diagnosis of rhombencephalosynapsis: the limits of intracranial translucency at 11–13 weeks – a plea for an evaluation of the aqueduct of Sylvius

VP24.03: Algorithmic approach to the follow‐up of fetuses with increased intracranial translucency at 11–14 weeks' scan

VP24.03: Algorithmic approach to the follow‐up of fetuses with increased intracranial translucency at 11–14 weeks' scan

VP04.02: Association of increased intracranial translucency in fetuses diagnosed with cleft palate at 11–14 weeks' scan

VP04.02: Association of increased intracranial translucency in fetuses diagnosed with cleft palate at 11–14 weeks' scan

Fetal Open and Closed Spina Bifida on a Routine Scan at 11 Weeks to 13 Weeks 6 Days.

This study aimed to determine the sensitivity of a first-trimester routine scan in detecting spina bifida (SB) and evaluating the first-trimester intracranial signs. This retrospective study was a review of a prospectively collected database. All cases of SB diagnosed in a tertiary center from 2008 to 2015 were identified. The ultrasound images and medical records were reviewed. All cases of SB diagnosed prenatally were confirmed at birth or autopsy. A total of 24 cases of SB were diagnosed from 53,349 pregnancy cases. Except for 10 cases with a body stalk anomaly, craniorachischisis, or iniencephaly, 7 cases with open spina bifida (OSB) and 7 cases with closed spina bifida (CSB) were analyzed. The first-trimester detection rates were 100% (7 of 7) for OSB and 28.5% (2 of 7) for CSB. Eight cases were highly suspected of SB in the first trimester because of an abnormal appearance of the posterior brain; 3 were false-positive cases. Two isolated cases of OSB had first-trimester intracranial signs. An obliterated cisterna magna (CM) showed the highest sensitivity for OSB but low specificity. Two cases of OSB had no discernible landmark of intracranial translucency and the CM, and 4 showed normal intracranial translucency with an obliterated CM. All CSB cases were coupled with a normal hind brain except for 2 cases. A first-trimester routine scan has high sensitivity in screening for OSB. The CM may be the most sensitive intracranial sign.

Reference ranges for the fetal mesencephalon to occiput measurement at 11 to 13+6 weeks of gestation.

The objective was to have a quantitative description of the normal position of the fetal midbrain in the first trimester, through defining the reference ranges for the mesencephalon to the occipital bone distance, in the axial plane. This was a prospective study that included normal fetuses screened between 11 and 13 weeks of gestation. The distance was measured between the posterior limit of the mesencephalon to the occipital bone in the same axial view as the one required for the biparietal diameter (BPD) assessment, at this gestational age (GA). The reference ranges using quantile regression, according to the crown-rump length (CRL), BPD, and GA were fitted. Data analysis included 428 ultrasound measurements. A good, linear correlation was observed between mesencephalon to occiput (MO) distance and CRL, BPD, or GA. It increased linearly with advancing gestation (log10MO = -0.1834 + 0.0092 x CRL, R2=0.48, P<0.0001) and was independent of maternal demographic characteristics and intracranial translucency (IT). In our study, the 1st percentile of the normal MO distance varies from 1.31 mm at a CRL of 45 mm to 2.08 mm at a CRL of 84 mm. The intraclass correlation coefficient (ICC) was 0.89 for intraobserver variability. A significant increase in the MO distance was found in the patients who did not receive folic acid in the first trimester of pregnancy [1.056 vs. 1.008 multiple of median (MoM), P=0.014]. A simple measurement is described between the midbrain and the occipital bone, obtained in the same axial view. It increases linearly with advancing gestation. Integration of this measurement into the routine ultrasound screening in association with the ‘crash sign’ and recognizing the lower extreme values could lead to an early diagnosis of open spina bifida (OSB).

Cranial sonographic markers of fetal open spina bifida at 11 to 13 weeks of gestation.

To compare the sonographic signs of spina bifida obtained on axial and sagittal views of the fetal head between 11 and 13+6 weeks of gestation. This was a retrospective study including 27 cases of spina bifida and 1003 randomly selected controls. Indirect markers of spina bifida were evaluated on stored ultrasound images. Intracranial translucency (IT), ratio between the brainstem and the brainstem-occipital bone distance (BS/BSOB), and maxillo-occipital (MO) line were assessed on sagittal view, whereas biparietal diameter (BPD), BPD to abdominal circumference ratio (BPD/AC), and aqueduct to occipital bone (aqueduct of Sylvius [AoS]) distance were measured on the axial plane. Reference ranges were developed, and cases of spina bifida were examined in relation to the reference range. On the sagittal view, detection rates for IT below the fifth percentile, BS/BSOB above the 95th percentile, and an abnormal MO line were 52.3%, 96.3%, and 96.3%, respectively. On the axial view, detection rates for BPD, BPD/AC, and AoS below the fifth percentile were 66.7%, 70.4%, and 77.8%, respectively. The MO line and the BS/BSOB ratio appear to be the best indirect ultrasound markers of spina bifida and can be easily obtained during the routine first-trimester scan.

EP07.20: Early detection and characterisation of CNS anomalies at 11–14 weeks in a mixed population attending a tertiary centre in a metropolitan city in India

To diagnose and characterise fetal CNS anomalies at 11-14 weeks of gestation to facilitate early management decisions. This was a retrospective analysis of 2377 pregnancies from a mixed economic and cultural background who underwent an 11-14 week-scan at a centre that provides primary, secondary and tertiary imaging care in Mumbai (India) between 2017 and 2018. Crown–rump length was 45 to 84 mm. The age range was 18-46 years (median 27 years). All scans followed ISUOG guidelines. The prevalence of CNS anomalies was about 1.09%. Of a total of 26 anomalous fetuses, 12 had an acrania-exencephaly sequence, 6 open spina bifida, 3 encephaloceles, 2 holoprosencephalies, 1 closed NTD and 2 suspected posterior fossa anomalies. 3 patients were lost to follow up. One encephalocele had associated Iniencephaly. Another had a double outlet right ventricle at 16 weeks follow up. Acrania-exencephaly was easily identified because of gross anatomical distortion. All open spina bifidas were suspected by nonvisualisation of the intracranial translucency. Complete or partial non-visualisation of the falx led to the diagnosis of holoprosencephaly. The overall prevalence of NTDs in India is high (0.05-1.1%) compared to other regions of the world, consequent to multiple factors possibly including lack of periconceptional folate supplementation, poor patient compliance, genetic predisposition and suboptimal ultrasound evaluation. These defects frequently give rise to quality of life issues. High end technology and operator skill enable early diagnosis. This potentially facilitates patient counseling and family decision making at a stage in pregnancy when termination, if opted for, is safer and psychologically simpler. EP07.20: Table 1. Various CNS anomalies found in our study Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.

Tekil gebeliklerin 11–13 hafta incelemesinde posterior fossada intrakraniyal saydamlık görüntüsünün elde edilememesi: Nedenler ve sonuçlar

Tekil gebeliklerin 11–13 hafta incelemesinde posterior fossada intrakraniyal saydamlık görüntüsünün elde edilememesi: Nedenler ve sonuçlar

Detection of Open Spina Bifida in the First Trimester: Beyond Intracranial Translucency

AbstractIntracranial translucency (IT) has been used extensively as an indirect marker to exclude open spina bifida (OSB) in the first trimester. Like any sonographic sign, the use of IT is fraught with issues like non-visualization due to shadowing from bone, poor distinction from the adjacent hypoechoic brainstem, etc. In view of these challenges, researchers have come up with additional markers of OSB in the first trimester. The aim of this paper is to illustrate these sonographic clues so as to improve diagnostic accuracy in cases where obliteration of IT is equivocal.

EP09.10: Obliteration of intracranial translucency: what next to do? Role of 3D in optimising detection of open spina bifida

EP09.10: Obliteration of intracranial translucency: what next to do? Role of 3D in optimising detection of open spina bifida

11–13. gebelik haftalarında dördüncü ventrikülün değerlendirilmesi ve intrakraniyal saydamlık nomogram

11–13. gebelik haftalarında dördüncü ventrikülün değerlendirilmesi ve intrakraniyal saydamlık nomogram