Ultrasonographic imaging of the fetal hippocampus

OBJECTIVES

The objective was to identify the fetal hippocampus and fornix using 2D and to measure the C-shaped length of fornix and hippocampus.

METHODS

This study was designed in cross-section. Healthy singleton and between 18 and 24 weeks of gestation pregnant women who applied to the perinatology outpatient clinic for second-level ultrasound scanning between December 2022 and February 2023 were included in the study. Patients were screened consecutively. Demographic information of the participants was obtained and an ultrasound scan was performed. The fetal fornix-hippocampus' length and hippocampal height were measured in the sagittal section. Data were presented as mean ± standard deviation, median (min, max), or number (percent).

RESULTS

A total of 92 patients were included in the study. Fetal fornix and hippocampus measurements were taken in % 97.8 (90/92) patients. The mean of the fetal fornix-hippocampus length and fetal hippocampus height of 90 patients were measured as 35.6 ± 3.0 and 4.7 ± 3.9, respectively.

CONCLUSION

Fetal fornix and hippocampus can be visualized in easily with two-dimensional ultrasound during anomaly scanning in the second trimester.

Differential Diagnostic Value of Two-dimensional Ultrasound Combined with Three-dimensional Ultrasound Imaging Technology for Cesarean Scar Pregnancy

BACKGROUND

Cesarean scar pregnancy (CSP) refers to the phenomenon in which a fertilized egg implants and develops in the scar of the uterus in a woman with a history of cesarean section.

OBJECTIVE

The study aimed to explore the differential diagnostic value of two-dimensional ultrasound (2D US) combined with three-dimensional ultrasound (3D US) for CSP.

METHODS

Clinical data of 89 patients with CSP admitted to our hospital from January 2022 to January 2023 were retrospectively analyzed. Of them, 65 patients met the inclusion criteria. Patients underwent 2D US, 3D US, and combined 2D and 3D US imaging. Using the clinical pathological diagnosis as the "gold standard", the differential diagnostic value of 2D US, 3D US, and 2D US combined with 3D US for CSP was compared.

RESULTS

The detection rate of CSP using a combined 2D US and 3D US was 98.46%, which was higher than 84.62% and 89.23% achieved with 2D US and 3D US alone, respectively (P<0.05). The pathological results showed that among 65 patients, CSP type I accounted for 24.62%, type II accounted for 55.38%, and type III accounted for 20.00%. The coincidence rate of 2D US combined with 3D US was 98.46%, which was higher than that of 2D US (83.08%) and 3D US 89.23%) alone (P<0.05). The accuracy, specificity, and sensitivity of 2D US combined with 3D US in diagnosing CSP were higher compared to the two methods alone (P<0.05).

CONCLUSION

The combination of 2D US and 3D US can accurately detect and classify CSP, further improving diagnostic efficiency.

Two-dimensional ultrasound results in underestimation of the ovarian follicle size compared to automated three-dimensional imaging in women undergoing IVF

BACKGROUND

Traditionally, for the assessment of follicle growth during IVF, two-dimensional (2D) transvaginal ultrasound (US) is used. In the past few years three-dimensional (3D) US has also been introduced.

OBJECTIVES

To compare follicular sizes between 2 and 3D ultrasound imaging on the final day of controlled ovarian stimulation.

METHODS

A prospective observational cohort study including 121 women undergoing controlled ovarian stimulation (COS) between January 2017 and July 2018. All women were assessed by transvaginal 2D and 3D ultrasonography to measure ovarian follicle dimensions on the final day of COS.

RESULTS

The mean difference in paired comparisons between the 3D and 2D US measurements in 25 women with monofollicular development was + 1.6 ± 2.5 mm for the x-dimension and + 1.7 ± 2.4 mm for the y-dimension; and in the total number of 1197 paired measurements of follicles the mean difference + 2.1 ± 3.3 mm and + 1.8 ± 3.9 mm for the x- and y-dimension respectively. In all cases the paired t-test showed that differences were statistically significant (p < 0.01). Further it was conjectured that the 2D underestimation results from the inherent difficulty to precisely place the US probe simultaneously on the perpendicular maximal of the x and y follicle diameters, leading to measurement errors that, by theory, are normally distributed. Running Monte-Carlo simulations based on these measurement errors it was found that both the mean difference and standard deviation are of the same magnitude as the ones found in real measurements, thus proving the conjecture.

CONCLUSIONS

The utilisation of 3D US results in different measurements of the follicular dimensions, and volumes, when compared to conventional 2D US. The differences in the x- and y-dimensions may affect the outcome of an IVF cycle as they are used to define the day of triggering final oocyte maturation, which is associated with the yield of mature oocytes and the probability of live birth.

Ultrasound Imaging of Hip Displacement in Children With Cerebral Palsy

OBJECTIVE

An approach to estimation of hip displacement on ultrasound (US) images is described. Its accuracy is validated through numerical simulation, an in vitro study with 3-D-printed hip phantoms and pilot in vivo data.

METHODS

A diagnostic index, migration percentage (MP), is defined by the ratio of acetabulum-femoral head distance to femoral head width. The acetabulum-femoral head distance could be measured directly on hip US images, while the femoral head width was estimated from the diameter of a best-fit circle. Simulation was performed to evaluate the accuracy of circle fitting with noiseless and noisy data. Surface roughness was also considered. Nine hip phantoms (three different sizes of femur head × three MP values) and 10 US hip images were used in this study.

RESULTS

The maximum diameter error was 16.1 ± 8.5% when the roughness and noise were 20% of the original radius and 20% of the wavelet peak, respectively. In the phantom study, the percentage errors of MPs between the 3-D-design US and X-ray US were 0.3%-6.6% and 0.0%-5.7%, respectively. From the pilot clinical trial, the mean absolute difference between the X-ray-US MPs was 3.5 ± 2.8% (1%-9%).

CONCLUSION

This study indicates that the US method can be used to evaluate hip displacement in children.

Fetal Hands: A Comprehensive Review of Prenatal Assessment and Diagnosis Over the Past 40 Years

Fetal skeletal dysplasias involving limbs and hands are rare congenital malformations. Prenatal two-dimensional ultrasound diagnosis of fetal limb defects has a sensitivity of about 30%; however, an increased detection rate may be obtained using three-dimensional (3-D) ultrasound in the rendering mode. 3-D ultrasound may be used as a complementary method providing additional information. Currently, magnetic resonance imaging (MRI), with the emergence of ultrafast imaging techniques and new sequences, allows for better diagnosis of several fetal skeletal dysplasias such as limb reduction defects and neuromuscular disorders. 3-D volumetric images from ultrasound or MRI scan data allow 3-D ultrasound reconstructions of virtual/physical models, and virtual reality can help researchers to improve our understanding of both normal and abnormal fetal limb/hand anatomy. In this article, we review the embryological development of fetal hands and their main anomalies including prenatal diagnostic methods, genetic counseling, the role of orthopedic and plastic surgery reconstruction, and new perspectives in fetal surgery.

Prediction of placenta accreta spectrum by a scoring system based on maternal characteristics combined with ultrasonographic features

OBJECTIVE

In order to create a comprehensive scoring system based on maternal characteristics and ultrasonographic features for predicting placenta accreta spectrum (PAS).

MATERIALS AND METHODS

This was a retrospective review of pregnant women who underwent routine ultrasound examination in the third trimester of pregnancy from January 2014 to November 2018 were used as a training set to establish the scoring system for PAS prediction while those who underwent examination from January 2019 to December 2019 served as a validation set.. Maternal characteristics including maternal age, parity, previous vaginal deliveries, previous curettage, previous cesarean section (CS), history of hypertension and diabetes mellitus, prenatal body mass index (BMI) were recorded. Ultrasonographic features including abnormal placental lacunae, subplacental hypervascularity, myometrial thinning, placental bulge, bladder wall interruption, location of placenta, placenta previa (yes or not) were recorded. Multivariate analysis was applied to analyze independent risk factors and assess the predictive power of selected parameters predicting PAS. Receiver operating characteristics (ROC) curve was used to evaluate the diagnosis power.

RESULTS

Parity, previous curettage and CS were independent risk factors. The best comprehensive scoring system was established as follow: the number of abnormal lacunae ≥3, 2 points; lacuna maximum dimension ≥2 cm, 5 points; subplacental hypervascularity (rich), 1 point; subplacental hypervascularity (extremely rich and disordered), 3 points; bladder wall interruption, 9 points; placental bulge, 9 points; placenta previa, 8 points; anterior placenta, 1 point; previous CS ≥ 1, 1 point; parity ≥ 4, 3 point; previous abortions ≥ 2, 1 point. The area under the ROC curve of the scoring system diagnosing PAS was 0.925. Sensitivity and specificity were 83.3% and 85.7%, respectively. Cross-validation for our model showed that sensitivity, specificity, positive predictive value and negative predictive value of the model in diagnosis of PAS were 82.6%, 81.8%, 82.6% and 81.8%, respectively. Diagnosis of 37 cases were consistent with the "gold standard", and the coincidence rate was 82.2% (37/45).

CONCLUSION

The comprehensive scoring system established in this study can effectively diagnose PAS.

Three-dimensional ultrasound improves identification of patients with abdominal aortic aneurysms reaching the threshold for repair

OBJECTIVE

Conventional two-dimensional ultrasound (2D-US) has been the recommended and preferred modality for the diagnosis and surveillance of abdominal aortic aneurysms (AAAs). Measurement of the aneurysm diameter using three-dimensional ultrasound (3D-US) has shown promising results in a research setting, improving agreement and reproducibility. However, studies evaluating 3D-US in a clinical context are lacking, which could hinder the optimal usage of this new modality. In the present study, we investigated the clinical value of 3D-US for AAA surveillance compared with the current standard 2D-US examination.

METHODS

Data from 126 patients with infrarenal AAAs <50 mm and 55 mm (female and male, respectively) were available for analysis. Eligibility was determined using the standard 2D-US anteroposterior (AP) diameter with a dual-plane technique. All the patients had subsequently undergone additional 3D-US and computed tomography angiography (CTA). Using CTA as the reference standard, the maximal standard 2D-US AP diameter was compared with that from 3D-US.

RESULTS

All 126 AAAs were, per the inclusion criteria, small, with no intervention indicated. With the addition of 3D-US imaging to the 2D-US-based surveillance program, the AAA diameter threshold (50 and 55 mm) was exceeded for 31 of the 126 patients (25%). These 31 patients were withdrawn from the present study and referred for treatment planning. Compared with the CTA AP diameter (mean, 49 ± 7.2 mm), the mean 3D-US AP diameter (mean, 49 ± 6.7 mm) was significantly more accurate than the standard mean 2D-US AP diameter (45 ± 6.2 mm; kappa value, 0.86 ± 0.05; 95% confidence interval, 0.76-0.96; kappa value, 0.01 ± 0.04; 95% confidence interval, -0.05 to 0.09, respectively).

CONCLUSIONS

For clinical use, the AAA diameter assessment using 3D-US was significantly more accurate than that with 2D-US and can substantially change the clinical management, from surveillance to operative treatment, for approximately one fourth of patients with an AAA. Further studies evaluating the clinical consequences of the 2D to 3D paradigm shift in AAA diagnostics are warranted, including sensitivity, specificity, agreement, and reproducibility estimation.

Three-dimensional ultrasound is a reliable alternative in endovascular aortic repair surveillance

OBJECTIVE

Three-dimensional ultrasound (3D-US) has already demonstrated improved reproducibility with a high degree of agreement (intermodality variability), reproducibility (interoperator variability), and repeatability (intraoperator variability) compared with conventional two-dimensional ultrasound (2D-US) when estimating the maximum diameter of native abdominal aortic aneurysms (AAAs). The aim of the present study was, in a clinical, multicenter setting, to evaluate the accuracy of 3D-US with aneurysm model quantification software (3D-US abdominal aortic aneurysm [AAA] model) for endovascular aortic aneurysm repair (EVAR) sac diameter assessment vs that of computed tomography angiography (CTA) and 2D-US.

METHODS

A total of 182 patients who had undergone EVAR from April 2016 to December 2017 and were compliant with a standardized EVAR surveillance program were enrolled from five different vascular centers (Rigshospitalet, Copenhagen, Denmark; Catharina Ziekenhuis, Eindhoven, Netherlands; L'hospital de la Timone, Paris, France; Cleveland Clinic, Cleveland, Ohio; and The Christ Hospital, Cincinnati, Ohio) in four countries. All image acquisitions were performed at the local sites (ie, 2D-US, 3D-US, CTA). Only the 2D-US and CTA readings were performed both locally and centrally. All images were read centrally by the US and CTA core laboratory. Anonymized image data were read in a randomized and blinded manner.

RESULTS

The sample used to estimate the accuracy of the 3D-US AAA model and 2D-US included 164 patients and 177 patients, respectively. The Bland-Altman analysis revealed that the mean difference between CTA and 3D-US was -2.43 mm (95% confidence interval [CI], -5.20 to 0.14; P = .07) with a lower and upper limit of agreement of -8.9 mm (95% CI, -9.3 to -8.4) and 2.7 mm (95% CI, 2.3-3.2), respectively. For 2D-US and CTA, the mean difference was -3.62 mm (95% CI, -6.14 to -1.10; P = .002), with a lower and upper limit of agreement of -10.3 mm (95% CI, -10.8 to -9.8) and 2.5 mm (95% CI, 2-2.9), respectively.

CONCLUSIONS

The 3D-US AAA model showed no significant difference compared with CTA for measuring the anteroposterior diameter, indicating less bias for 3D-US compared with 2D-US. Thus, 3D-US with AAA model software is a viable modality for anteroposterior diameter assessment for surveillance after EVAR.

Size measurements of hepatocellular carcinoma: comparisons between contrast and two-dimensional ultrasound

Background

Ultrasound (US) imaging is known to underestimate tumor size in clinical. This study is aimed to compare the size measurements of hepatocellular carcinoma (HCC) in three US imaging modalities, i.e. two-dimensional (2D) imaging, the arterial phase (AP) and the late phase (LP) imaging of contrast-enhanced US (CEUS).

Methods

Fifty-eight clinically proved HCC patients were included. The 2D and CEUS imaging were performed with Siemens S2000, Philips iu22 and BioSound Twice. 2.5 mL of SonoVue® was injected for every CEUS performance. Two physicians measured the maximal longitudinal and the transverse diameters of the tumors in 2D, the AP and the LP of CEUS from one image section. The three measurements were compared by paired t test.

Results

The mean longitudinal diameter of HCC appeared to be maximal in the AP (4.73 ± 2.04 cm) of CEUS and minimal in the LP (3.98 ± 1.99 cm) of CEUS. The 2D diameter (4.26 ± 2.07 cm) was in the middle between two CEUS measurements. There were significant differences between any two measurements.

Conclusion

There is size difference between the three kinds of HCC measurement. It appeared to be maximal in the AP of CEUS and minimal in the LP. The 2D diameter was in the middle.

Impact of type I and type II maternal diabetes mellitus on fetal cardiac function assessment parameters using spectral and tissue Doppler

The aim of this study was to evaluate the impact of pregestational diabetes mellitus (DM) on fetal cardiac function two-dimensional parameters using spectral and tissue Doppler. Pregnant women between 20 and 36 + 6 weeks gestation were divided into three groups: controls, type I DM, and type II DM. The right ventricle (RV) and left ventricle (LV) annular velocity peaks were measured using spectral (E, A) and tissue (E', A', S') Doppler. The myocardial performance index was calculated as (isovolumetric contraction time [ICT] + isovolumetric relaxation time [IRT])/ejection time using tissue (MPI') and the spectral Doppler (MPI). A general linear model, with fetal heart rate as a covariant, was used to evaluate the effect of DM on the fetal heart function assessment parameters. To assess the association of type I and II DM with adverse perinatal outcomes, Fisher's exact test was used. A receiver operating characteristic curve was used to determine the best cutoff for fetal cardiac function assessment parameters to identify the neonatal composite outcomes. The sample comprised 179 pregnant women. DM had significant effect on RV and LV A peak velocities (p = 0.026 and p = 0.011, respectively). LV ICT (p < 0.001) and LV MPI (p < 0.001) were significantly affected by maternal DM. Fetuses from pregnant women with type II DM showed significantly higher LV MPI (0.492 vs. 0.459, p = 0.006) and RV S' (7.2 vs. 6.44 cm/s, p = 0.024) than controls. Fetuses from type I DM pregnant women showed increase in cardiac parameters that evaluated the LV and RV diastolic function (LV IRT' p < 0.001 and RV MPI' p = 0.044). Type I and II DM were associated with adverse perinatal outcomes: neonatal intensive care unit stay (p < 0.0001), macrosomia (p < 0.0001), hyperbilirubinemia (p < 0.0001), and hypoglycemia (p < 0.0001). The LV MPI' showed significant but moderate sensitivity in identifying the composite neonatal outcomes (AUC: 0.709, 95% CI 0.629-0.780, p < 0.001). Tissue Doppler and MPI parameters can be useful to detect subclinical cardiac dysfunction in the fetal heart of pregestational DM pregnant women.

Diagnostic Value of Two-Dimensional plus Four-Dimensional Ultrasonography in Fetal Craniocerebral Anomalies

BACKGROUND

To assess the clinical value of two-dimensional (2D) plus four-dimensional (4D) ultrasonography in diagnosis of fetal craniocerebral anomalies.

METHODS

Retrospective analysis was performed on the sonographic features of 83 maternity patients admitted to Northwest Women's and Children's Hospital, Xian China from January 2013 to December 2017 diagnosed with suspected fetal anomalies of the brain and skull through 2D and 4D ultrasonography.

RESULTS

Fifty six patients were diagnosed with the anomalies by 2D ultrasonography only, 65 patients by 4D ultrasonography only, and 74 patients by 2D plus 4D ultrasonography.76 patients were confirmed to have fetal craniocerebral anomalies after birth or induced labor. Diagnostic accuracies of 2D ultrasound only, 4D ultra-sound only, and 2D plus 4D ultrasound were 68.67%, 81.93% and 95.18%, respectively (P<0.05). The accuracy of 2D plus 4D ultrasound was greater than those of 2D ultrasound only and 4D ultrasound only, and the accuracy of 4D ultrasound only was higher than that of 2D ultrasound only (P<0.05). The sensitivity of 2D plus 4D ultrasound was greater than those of 2D ultrasound only and 4D ultrasound only (P<0.05). The specificity of 2D plus 4D ultrasound was greater than those of 2D ultrasound only and 4D ultrasound only (P<0.05).

CONCLUSION

Combined ultrasonography can better differentiate fetal craniocerebral anomalies, providing early and more accurate information for clinicians as well as maternity patients to make a decision. This clinical practice would be valuable for improving the quality of the newborn population.

Off-site evaluation of three-dimensional ultrasound for the diagnosis of thyroid nodules: comparison with two-dimensional ultrasound

OBJECTIVES

We compared the diagnostic performance of off-site evaluation between prospectively obtained 3D and 2D ultrasound for thyroid nodules.

METHODS

3D and 2D ultrasonographies were preoperatively obtained from 85 consecutive patients (mean age, 51 years; age range, 28-83 years) who were referred for a total thyroidectomy. Three radiologists independently evaluated 3D and 2D images of 91 pathologically confirmed thyroid nodules (30 benign and 61 malignant nodules) for nodule characterization. Diagnostic performance, interobserver agreement and time for scanning were compared between 3D and 2D.

RESULTS

3D had significantly higher sensitivities than 2D for predicting malignancy (78.7 % vs. 61.2 %, P < 0.01) and extrathyroidal extension (66.7 % vs. 46.4 %, P = 0.03) in malignancy. In terms of specificities, there were no statistically significant differences between 2D and 3D for predicting malignancy (78.4 % vs. 74.8 %, P = 1.00) and extrathyroidal extension (63.6 % vs. 57.6 %, P = 0.46). With respect to interobserver agreement, 3D showed moderate agreement (κ = 0.53) for predicting extrathyroidal extension in malignancy compared with 2D ultrasound, which showed fair agreement (κ = 0.37). 3D saved time (30 ± 56.52 s) for scanning compared with 2D.

CONCLUSION

For off-site evaluation, 3D US is more useful for diagnosis of thyroid nodules than 2D US.

KEY POINTS

• 3D had higher sensitivity than 2D for predicting malignancy and extrathyroidal extension. • 3D showed better agreement for predicting extrathyroidal extension in malignancy than 2D. • 3D thyroid ultrasound saved time for scanning compared with 2D. • For off-site evaluation of thyroid nodules, 3D is more useful than 2D.

Feasibility of three-dimensional reconstruction and automated measurement of fetal long bones using 5D Long Bone

Objective

To evaluate the feasibility of five-dimensional Long Bone (5D LB), a new technique that automatically archives, reconstructs images, and measures lengths of fetal long bones, to assess whether the direction of volume sweep influences fetal long bone measurements in three-dimensional (3D) ultrasound and 5D LB, and to compare measurements of fetal long bone lengths obtained with 5D LB and those obtained with conventional two-dimensional (2D) and manual 3D techniques.

Methods

This prospective study included 39 singleton pregnancies at 26+0 to 32+0 weeks of gestation. Multiple pregnancies, fetuses with multiple congenital anomalies, and mothers with underlying medical diseases were excluded. Fetal long bones of the lower extremities-the femur, tibia, and fibula were measured by 2D and 3D ultrasound, and 5D LB, by an expert and non-expert examiner. First, we analyzed the 3D ultrasound and 5D LB data according to 2 different sweeping angles. We analyzed intra- and inter-observer variability and agreement between ultrasound techniques. Paired t-test, interclass correlation coefficient, and Bland-Altman plot and Passing-Bablok regression were used for statistical analysis.

Results

There was no statistical difference between long bone measurements analyzed according to 2 different volume-sweeping angles by 3D ultrasound and 5D LB. Intra- and inter-observer variability were not significantly different among all 3 ultrasound techniques. Comparing 2D ultrasound and 5D LB, the interclass correlation coefficient for femur, tibia, and fibula was 0.91, 0.92, and 0.89, respectively.

Conclusion

5D LB is reproducible and comparable with conventional 2D and 3D ultrasound techniques for fetal long bone measurement.

Prenatal diagnosis of intracranial immature teratoma in the third trimester using 2D and 3D sonography

Intracranial tumors are uncommon and represent 0.5-1.5 % of all pediatric tumors. Teratoma is the most frequent intracranial tumor found at birth. Large teratomas are extremely rare and have a guarded prognosis since they grow fast and cause brain tissue destruction. A 31-week primigravida was referred to our hospital for investigation of an intracranial mass seen in the fetus. Two-dimensional ultrasound showed a large heterogeneous solid mass with calcifications inside, measuring 5.3 × 4.8 cm. It was in the right cerebral hemisphere at the level of the middle and posterior fossa, thereby shifting the midline and causing severe ventriculomegaly that measured 3.5 cm at the level of the lateral ventricle. Three-dimensional ultrasound (3DUS) in multiplanar mode allowed us to assess the anatomical relationships between the mass and the midline structures. The neurosurgical team, who had suspected that the case was inoperable, was thus able to gain a better understanding of the case. Transfontanellar ultrasound was performed on the day after the birth and confirmed the previous findings. Moreover, a biopsy confirmed the histology of the mass: it was an immature teratoma. The infant died on the 24th day of life after a large expansion of head circumference. Intracranial teratomas are extremely severe because of their quick growth and mass effect, often leading to neonatal death within days. 3DUS is a new prenatal diagnostic method that makes it possible to assess the anatomical relationships between the mass and the intracranial structures, thus enabling better preoperative planning.