**5. Fetal medicine**

Advances in image-scanning technology have led to vast improvements in fetal medicine [14– 16].

In general, three main technologies are used to obtain images within the uterus during pregnancy—ultrasound, MRI, and CT. US is currently the primary method for fetal assessment during pregnancy because it is patient-friendly, useful, cost-effective, and considered to be safe. When ultrasound yields equivocal results, MRI can be used to help in diagnosis. CT can be used after 30 weeks of gestation only in cases of skeletal dysplasias [3, 17].

The development of ultrasound scanning during the 1960s opened a new window into the study of the fetus. Its introduction in the clinical obstetrics practice allowed the opportunity to make screening of many malformations (**Figures 7**–**10**).

**Figure 7.** A and B. 3D printed hollow model of a head of a 32-week fetus from magnetic resonance imaging (MRI) highlighting fetal upper respiratory tract model positioned on measuring scale table (scale reference: 1 cm2 )—3D print‐ ed in polyamide (EOS P110)––Instituto Nacional de Tecnologia—Laboratório de Modelos Tridimensionais—Ministério da Ciência, Tecnologia e Inovação.

**Figure 8.** A and B. 3D full-scale model of the skull of neonate with microcephaly from CT scanner, model positioned on measuring scale table (scale reference: 1 cm2 )—3D printed in polyamide (EOS P110)––Instituto Nacional de Tecno‐ logia—Laboratório de Modelos Tridimensionais—Ministério da Ciência, Tecnologia e Inovação.

**5. Fetal medicine**

118 New Trends in 3D Printing

da Ciência, Tecnologia e Inovação.

on measuring scale table (scale reference: 1 cm2

16].

Advances in image-scanning technology have led to vast improvements in fetal medicine [14–

In general, three main technologies are used to obtain images within the uterus during pregnancy—ultrasound, MRI, and CT. US is currently the primary method for fetal assessment during pregnancy because it is patient-friendly, useful, cost-effective, and considered to be safe. When ultrasound yields equivocal results, MRI can be used to help in diagnosis. CT can

The development of ultrasound scanning during the 1960s opened a new window into the study of the fetus. Its introduction in the clinical obstetrics practice allowed the opportunity

**Figure 7.** A and B. 3D printed hollow model of a head of a 32-week fetus from magnetic resonance imaging (MRI)

ed in polyamide (EOS P110)––Instituto Nacional de Tecnologia—Laboratório de Modelos Tridimensionais—Ministério

**Figure 8.** A and B. 3D full-scale model of the skull of neonate with microcephaly from CT scanner, model positioned

logia—Laboratório de Modelos Tridimensionais—Ministério da Ciência, Tecnologia e Inovação.

)—3D printed in polyamide (EOS P110)––Instituto Nacional de Tecno‐

)—3D print‐

highlighting fetal upper respiratory tract model positioned on measuring scale table (scale reference: 1 cm2

be used after 30 weeks of gestation only in cases of skeletal dysplasias [3, 17].

to make screening of many malformations (**Figures 7**–**10**).

**Figure 9.** A and B. Fetal heart at 38 weeks, after autopsy, being positioned inside a micro-CT scanner (Zeiss Xradia Versa 510) and 3D virtual model generated from the DICOM micro-CT files—Department of Chemical and Materials Engineering—Rio de Janeiro, Brazil—DEQM/PUC-Rio and 3D printed models (3D Systems PROJET 3510 HD Plus) — Núcleo de Experimentação Tridimensional—NEXT PUC-Rio.

**Figure 10.** 3D printed full-scale model of human fetal heart (38 weeks) from micro-CT scanner files —SLA system (3D Systems PRO-7 JET 3510 HD Plus)—Núcleo de Experimentação Tridimensional—NEXT PUC-Rio.

MRI is a noninvasive procedure that has been utilized in obstetrics since the 1980s. It offers digital files with exceptional image contrast allowing a great visual comprehension of the fetus internal tissues. When the use of ultrasound detects or produces unexpected results, MRI is often adopted, since it provides further information about fetal malformations and conditions for which ultrasound cannot generate superior images [18].

MRI files can generate detailed characteristics of the soft tissues of the fetus body as the face, hands, or feet as well as internal body structures as aerial paths. The construction process of the 3D accurate virtual model starts with the 3D modeling volume built through the MRI slices sequentially mounted, followed by the segmentation process where the physician selects the important body parts to be analyzed that will then be reconstructed in 3D [19].

Fetal 3D physical models from 3DUS and MRI scan data have been used in blind pregnant women to improve maternal fetal attachment [20, 21].
