Three-dimensional ultrasound (3DUS) imaging is a new technique that allows imaging from volume sonographic data rather than conventional planar data. The volume data can be viewed as a three-dimensional object and displayed in multiplanar mode in three orthogonal planes or in various modes of rendering that can be selected singularly or combined to optimize the visualization of soft tissues, bony structures or vessels.

The 4D imaging has introduced a temporal dimension to the 3D volumetric scansion, associating movement to representation of volumes.

3DUS provides the ability to examine the embryo and the fetus at the first trimester in any arbitrary plane. Various studies have reported a better visualization of the structures in normal fetuses as well as malformed ones, regarding selected cases of facial structures, cranium, abdominal wall and limbs.

3DUS technique is also being considered for measurement of nuchal translucency and the evaluation of the nasal bones.

Several reports exist on the application of 3D-4D techniques regarding conjoined twins.

4DUS allows the evaluation of fetal motorial and behavioral patterns.

3D-4D techniques are seen as a powerful complement to conventional ultrasound, but not a substitution to it.

Three-dimensional ultrasound is the most innovating and attracting modality in the field of ultrasound imaging and represents a superb tool to perform an accurate fetal neuroscan. Once the fetal brain has been scanned, it is then possible to “navigate” in the stored volume choosing among the multiple scanning planes on the three orthogonal spatial axes. Last generation 3D equipments have multiple software facilities which are extremely useful to correctly evaluate the fetal brain such as the multiplanar view, the tomographic ultrasound imaging (TUI), the volume contrast imaging in the C plane (VCI-C plane), the volume calculation, the surface rendering, the 3D color and power Doppler. Thanks to these imaging modalities it is possible to evaluate the finest anatomical details of the developing brain and to increase the diagnostic accuracy when an abnormal sonographic finding of the fetal brain is recognized during the routine examination.

Neurological failure is the most apprehension complication of pregnancy, labor and the neonatal period. The origin and outcome correlation is frequently doubtful. The arrival of four-dimensional ultrasonography (4D US) and its function to study fetal behavior patterns have initiated to offer insight into the structural and functional fetal brain development. Although many fetal behavioral studies have been conducted, it is still questionable whether the assessment of continuity from fetal to neonatal behavior could improve our ability of early detection of brain pathology. Neurological assessment of fetus in utero is extremely difficult even having such sophisticated equipment like 4D ultrasound. As it is well known that quantity of GMs is not so informative and predictive for neurological impairment, their quality should be assessed. Gestalt perception of premature GMs we are dealing with in utero and several weeks postnatally are not as predictive for the detection of neurologically abnormal fetuses or newborns as fidgety GMs. Therefore some additional parameters should be added to the prenatal neurological examination in order to improve our ability to make the distinction between normal and abnormal fetuses.

There are few 3D well-documented studies about thoraco- abdominal malformations, except for the evaluation of fetal lung volume. Three-dimensional ultrasound provides additional diagnostic information for the evaluation of fetal thorax both for the diagnosis of skeletal anomalies and the biometric measurements of lungs.

3D adds few information about the diagnosis of gastrointestinal malformations, but 3D images are an effective tool to make a careful advice with parents and pediatric surgeons, especially in fetuses with anterior wall defects.

Until now its use must be reserved in a research setting and offered to high-risk patients in order to understand which role 3D may play in the study of thoraco-abdominal malformations as a screening or diagnostic tool.

Even if ultrasonography still remains the primary prenatal investigation technique for the assessment of fetal development, magnetic resonance imaging (MRI) plays an important role for the study of fetal morphology and pathology.

MRI has been shown to be particularly useful for the evaluation of the central nervous system (CNS), the latter being a common site of pathology such as cerebral and spinal malformations.

MRI is contributive in defining fetal neck, thoracic, abdominal, and pelvic masses. This can be especially helpful when differing opinions exists as to the etiology of a mass.

Ultrasonography, a non invasive, low cost, real time technique, still represents the investigation of choice in prenatal screening, not only regarding the CNS. Nevertheless several cases need a diagnostic complement by means of MRI, that increases the diagnostic potential of ultrasound .

The additional information from MRI is important in prenatal counseling, delivery planning and planning for pre- or postnatal intervention.

The present paper, and its graphic back-up, are intended as a visual testimony of the fact that 3D ultrasound is much more than a simple generator of “nice”, commercial, images. Moreover, its use may be extended from obstetrics to gynecological pathology, especially in cases related to infertility.

we performed a review of the main local infertility causes and their perception by the three dimensional ultrasound, as compared to the conventional methods. General literature citations were completed with personal cases and images. In our research we used a Kretz – Voluson Expert 730 ultrasound machine with a full logistic equipment. Our database was completed over a period of 18 months and included various pathology, such as uterine anomalies, fibroids, polyps, ovarian cysts and many others.

Three dimensional ultrasound represents the best tool in evaluating the uterine cavity, the endometrium, assessing its volume and vascularity pattern. It also offers a very good image of the uterine structure, the adnexal morphology and their relationship. It performs a thorough pelvic assessment by a single examination. Moreover, it may realize a histerosalpingography, which is as efficient as the radiological method, but easier and with less side effects.

Even though it is technically more difficult and time consuming, a good practice and a high quality ultrasound equipment offer a series of benefits over any other kind of investigation.