Three-dimensional (3D) and four-dimensional (4D) ultrasound imaging has long ceased to be exclusively a marketing advantage of modern ultrasound systems. Today, these technologies are an important diagnostic tool in prenatal medicine, fetal cardiology and gynecology. At the same time, the cost of equipment with support for volumetric scanning remains higher compared to standard systems, which naturally raises the question: are investments in 3D/4D functionality always clinically justified?
The main advantage of 3D ultrasound over traditional two-dimensional scanning is the ability to obtain a volumetric data set with subsequent reconstruction of the anatomical structure under study in any plane. The doctor receives not a separate slice, but a digital volume of tissues that can be analyzed repeatedly without the need for a new scan of the patient.
The most obvious application of 3D/4D technologies is associated with prenatal diagnostics. Volumetric imaging significantly improves the assessment of the anatomy of the fetal face, limbs, spine and anterior abdominal wall. Such malformations as cleft lip and palate, limb deformities, neural tube defects or anomalies of the development of external structures are often visualized more clearly compared to the standard two-dimensional mode. The key advantage is not only in increasing diagnostic accuracy, but also in the ability to document the results and conduct expert analysis of the obtained volume.
Among modern volumetric imaging technologies, the Brilliant Flow mode deserves special attention. Unlike classic color Doppler mapping, this technology provides a more realistic display of blood flow with the effect of spatial depth and volume. In fact, Brilliant Flow can be considered as an improved version of color Doppler, which allows better visualization of the boundaries of blood vessels and heart chambers without excessive noise and artifacts characteristic of standard Doppler modes.
In prenatal diagnostics, the technology is most often used during the study of the fetal cardiovascular system. Volumetric visualization of blood flows helps to more clearly assess the anatomy of the heart chambers, the relative location of the main vessels and the features of intracardiac hemodynamics. Thanks to the high level of detail, the doctor receives additional information about the spatial structure of the fetal heart, which is especially important when congenital malformations of the cardiovascular system are suspected.
Another technology that has significantly increased the clinical value of volumetric ultrasound is the STIC (Spatial Temporal Image Correlation) mode. This technique is specially designed for the study of the fetal heart, allowing you to visualize the heart or vascular network in 3D/4D modes. This imaging method is designed both for visualization of the heartbeat and for organs supplied with blood.
Traditional examination of the fetal heart requires considerable operator experience, since obtaining the necessary diagnostic slices depends on the position of the fetus and the skills of the doctor. STIC allows you to save the full volume of the heart for further analysis and reconstruction of any necessary planes. This significantly improves the detection of complex congenital heart defects, including transposition of the great vessels, ventricular septal defects, anomalies of the outflow of great vessels and complex combined cardiac defects. In addition, the saved volumetric data can be transmitted to specialized fetal cardiology centers for remote expert assessment.
In gynecology, the possibilities of 3D visualization also go far beyond obtaining a more spectacular image. One of the most valuable applications is the assessment of the uterine cavity and congenital anomalies of its development. It is the three-dimensional scanning that allows you to obtain the coronal plane of the uterus, which is practically inaccessible with a standard two-dimensional study. This is of great importance for the diagnosis of bicornuate uterus, septate uterus, arcuate uterus and other anomalies of the development of the Müllerian ducts.
3D ultrasound also plays an important role in reproductive medicine. Volumetric examination allows for a more accurate assessment of the state of the endometrium, the localization of submucosal myomatous nodes, the position of intrauterine contraceptives and the results of reconstructive interventions. In ovarian pathology, volumetric reconstruction helps to analyze the structure of neoplasms and the features of their vascularization. The use of 3D Power Doppler in combination with morphological assessment increases the informativeness of differential diagnosis between benign and potentially malignant formations.
Despite the numerous advantages, 3D/4D technologies are not mandatory for every ultrasound examination. For general abdominal diagnostics, thyroid gland, vascular or musculoskeletal examination, the clinical value of volumetric scanning often remains limited. That is why investments in such systems should be evaluated through the prism of the specialization of the medical institution.
The most justified 3D/4D solutions are for prenatal diagnostic centers, obstetric and gynecological clinics, reproductive medicine centers and departments of fetal cardiology. In these areas, volumetric visualization has long become not just an additional function, but an important tool that allows you to increase diagnostic accuracy, improve the detection of complex developmental anomalies and ensure better planning of further patient management tactics.
In addition to its purely diagnostic value, 3D/4D visualization also has an important psychological aspect. Numerous studies have shown that a realistic image of the face contributes to the formation of an early emotional connection between the mother and the future child. For many women, the opportunity to see the facial features of the fetus, its facial expressions reduces the level of anxiety during pregnancy and has a positive effect on the psycho-emotional state. This is especially true for patients after long-term infertility treatment, previous unsuccessful pregnancies or pregnancies belonging to the high-risk group. Although this effect does not have direct diagnostic value, its importance for the psychological comfort of the future mother should not be underestimated.
It is precisely because of the ability to create realistic images of the fetus that 3D/4D technologies have become an important marketing positioning tool for modern obstetric clinics and diagnostic centers. Many patients associate the presence of volumetric visualization with a higher technological level of a medical institution, which affects the choice of the examination location. At the same time, modern ultrasound systems offer much more than just obtaining beautiful images. Leading models of ultrasound machines have implemented the ability to export volumetric data into formats suitable for further processing and 3D printing. Based on the obtained ultrasound volumes, physical three-dimensional models of the face or body of the fetus can be created, printed on a 3D printer. Such models are used both to create memorable souvenirs for parents and in individual clinical cases for a detailed study of complex congenital malformations and planning further patient management tactics.
Thus, modern 3D/4D technologies justify investments when used not as a means of demonstrating realistic images of the fetus, but as a full-fledged tool for expert diagnostics. The greatest clinical value today is the volumetric assessment of fetal anatomy, visualization of the vascular bed, examination of the fetal heart in the STIC mode, and three-dimensional gynecological diagnostics, which significantly expand the capabilities of modern ultrasound examination.
