Simone Belmonte

Applicability of three-dimensional imaging techniques in fetal medicine

Objective To generate physical models of fetuses from images obtained with three-dimensional ultrasound (3D-US), magnetic resonance imaging (MRI), and, occasionally, computed tomography (CT), in order to guide additive manufacturing technology. Materials and Methods We used 3D-US images of 31 pregnant women, including 5 who were carrying twins. If abnormalities were detected by 3D-US, both MRI and in some cases CT scans were then immediately performed. The images were then exported to a workstation in DICOM format. A single observer performed slice-by-slice manual segmentation using a digital high resolution screen. Virtual 3D models were obtained from software that converts medical images into numerical models. Those models were then generated in physical form through the use of additive manufacturing techniques. Results Physical models based upon 3D-US, MRI, and CT images were successfully generated. The postnatal appearance of either the aborted fetus or the neonate closely resembled the physical models, particularly in cases of malformations. Conclusion The combined use of 3D-US, MRI, and CT could help improve our understanding of fetal anatomy. These three screening modalities can be used for educational purposes and as tools to enable parents to visualize their unborn baby. The images can be segmented and then applied, separately or jointly, in order to construct virtual and physical 3D models.

Prenatal diagnosis and physical model reconstruction of agnathia–otocephaly with limb deformities (absent ulna, fibula and digits) following maternal exposure to oxymetazoline in the first trimester

Agnathia–otocephaly or agnathia‐sinotia‐microstomy syndrome is the most severe malformation affecting the first branchial arch. It is a rare congenital anomaly characterized by absence of the lower jaw and abnormal ear positioning. Prenatal diagnosis is possible on conventional 2‐D ultrasound in the second trimester. Three‐dimensional ultrasound enhances detection of abnormal facial phenotype, especially in surface rendering mode. In addition, 3‐D volume datasets are used to produce a physical model of the anomaly. We present a case of second trimester ultrasound diagnosis of agnathia–otocephaly associated with limb deformities. A physical model produced using 3‐D ultrasound volume datasets facilitated better understanding of this congenital malformation, and improvement of parental counselling and management by the multispecialist team.

Virtual bronchoscopy through the fetal airways in a case of cervical teratoma using magnetic resonance imaging data.

Cervical teratomas are rare congenital tumors, usually solid or cystic (3–5% of all teratomas), with an incidence of 1:20 000 to 1:40 000 among live births (Nascimento et al. 2007). This malformation is usually diagnosed during the prenatal period by ultrasound exam in the second and third trimesters. Knowledge about the degree of compression of the fetal airways during the prenatal period is important for the obstetrician/neonatology team to plan the correct management strategy during delivery (Azizkhan et al. 1995). A 28-year-old primiparous pregnant woman was referred to our service with a diagnosis of fetal neck mass at 21 weeks during the second trimester ultrasound exam. Another ultrasound exam showed a large solid/cystic mass measuring 41 × 24 mm in the fetal cervical region, and no other fetal abnormalities were observed. Subsequent follow-up ultrasound exams showed a normal amniotic fluid index. We decided to perform a three-dimensional ultrasound (3DUS) and magnetic resonance imaging (MRI) at 36 weeks for a better assessment of the fetal airways to plan the delivery (Fig. S1). The ultrasound exam was performed using a Voluson E8 apparatus (General Electric Medical System, Zipf, Austria) equipped with a convex probe (RAB 4-8L). The 3D images were shown on the screen in multiplanar (three orthogonal planes–axial, sagittal, and coronal) and rendering modes. The MRI exam was performed using a 1.5-T scanner (Siemens, Erlangen, Germany). The protocol involved a T2-weighted sequence in the three planes of the fetal body (HASTE; repetition time (TR), shortest; echo time (TE), 140 ms; field of view, 300–200 mm; matrix, 256 × 256; slice thickness, 4 mm; acquisition time, 17 s; 40 slices). In addition, we applied 3D T2-weighted true fast imaging with a steady-state precession (true fisp) sequence in the sagittal plane (TR, 3.02 ms; TE, 1.34 ms; voxel size, 1.6 × 1.6 × 1.6 mm; FA, 70; PAT, 2; acquisition time, 0.26 s). The entire examination time did not exceed 30 min (Fig. S2). A 3D physical model of the fetal airways was generated using the overlapping image layers generated by the MRI, using the software Mimics (Materialise, Leuven, Belgium), which allowed delineation of the airway surface using contrast detection in the relevant areas of interest. The generated 3D model was exported using the standard triangular language file format and then converted into an OBJ file using the MAYA 3D modeling software (Autodesk, San Rafael, CA, USA). The software allowed the correct virtual positioning of the observation cameras, while working with multiple onscreen windows, and the lighting parameters could also be adjusted to optimize the visualization. Finally, a path was plotted through the 3D model to create a simulated movie for the analysis of the fetal airway (Fig. 1). A virtual navigation through the fetal airways allows the visualization of the upper respiratory tract from the pharynx downward through the tracheobronchial tree. In our case, the virtual bronchoscopy did not identify the compression of the fetal airways (Video clip). A cesarean section was planned at 37 weeks, through which the woman gave birth to a live female baby weighing 3.175 g, with a height of 49.5 cm, and Apgar scores of 8 and 9 at the 1 and 5 min, respectively. After 48 h of delivery, the neck mass was surgically removed, without the need for endotracheal intubation. Both the mother and child were discharged from the hospital on the 7 day after delivery. Virtual bronchoscopy is a new, noninvasive technique that allows the assessment of patency of the fetal airways (Werner et al. 2011). The efficacy of this technique in assessing the fetal airway patency has been proven in four fetuses with cervical teratomas (Werner et al. 2013). In our case report, the virtual bronchoscopy confirmed the fetal airway patency and allowed an adequate management of the delivery by the obstetrician/neonatology team, without the necessity of invasive procedures such as ex utero intrapartum treatment (EXIT). In summary, we reported a case of fetal cervical teratoma with a favorable postnatal outcome using virtual navigation through the fetal airways. We believe that virtual bronchoscopy may be an effective method to assess the fetal airway patency in cases of neck masses or other extrinsic compressive lesions of the upper respiratory tract.

Additive Manufactured Models of Fetuses Built from 3D Ultrasound, Magnetic Resonance Imaging and Computed Tomography Scan Data

Jorge Lopes Santos1, Heron Werner2, Ricardo Fontes3 and Simone Belmonte4 1Laboratorio de Modelos Tridimensionais, Instituto Nacional de Tecnologia (INT), Laboratorio de Processamento de Imagens Digitais, Museu Nacional (UFRJ), Laboratorio de Modelagem e Simulacao 3D Departamento de Artes e Design, (PUC-Rio), Rio de Janeiro 2Radiologia, Clinica de Diagnostico por Imagem (CDPI), Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro 3Laboratorio de Modelos Tridimensionais, Instituto Nacional de Tecnologia (INT), Rio de Janeiro 4Laboratorio de Modelos Tridimensionais, Instituto Nacional de Tecnologia (INT), Laboratorio de Processamento de Imagens Digitais, Museu Nacional (UFRJ), Rio de Janeiro, Brazil

Combination of Non Invasive Medical Imaging Technologies and Virtual Reality Systems to Generate Immersive Fetal 3D Visualizations

Advances in imaging technology have led to vast improvements in fetal evaluation. Ultrasound examination is the primary method of fetal assessment because it is patient friendly, effective, and cost efficient and is considered to be safe. Magnetic resonance imaging is generally used when ultrasound cannot provide sufficiently high-quality images. It offers high-resolution fetal and placental imaging with excellent contrast. The objective here is to describe the combination of non-invasive medical imaging technologies and virtual reality systems in fetal medicine.

Combination of ultrasound, magnetic resonance imaging and virtual reality technologies to generate immersive fetal 3D visualizations during pregnancy for fetal medicine studies

Advances in imaging technology have led to vast improvements in medicine, especially in the diagnosis of fetal anomalies. In general, two main technologies are used to obtain images within the uterus during pregnancy: ultrasound and magnetic resonance imaging (MRI). Ultrasound is an indispensable tool in fetal medicine, but when it yields unexpected results, MRI is generally performed. MRI can provide high-resolution fetal images

OP23.08: Virtual bronchoscopy in the fetus

Results: 218 patients were included. Average BMI was 34.2 (range 30–54.3) with 10.5% women with BMI > 40. Mean ultrasound duration was 31.7 minutes. Screeners could not perform a complete scan in 23% whereas only 11% experts could not produce the entire 17 pictures. Failure reasons were high BMI level, early gestation age, increased DSU, old sonograph and fetal transverse presentation. Concordance between expert reviewer and screeners were good (Kappa = 0.61), whereas it was excellent between reviewer and experts (Kappa = 0.82). Conclusions: Performing ultrasound scan among obese pregnant women is feasible for screeners but remains a challenge when BMI is over 40 or DSU is over 36cm, and therefore should be performed by trained sonographers at 24 weeks, with 45 minutes timing.

OC10.06: Additive manufacturing technologies applied in fetal medicine researches

Objectives: To generate physical fetal models using images obtained by 3-dimensional ultrasound (3DUS), magnetic resonance (MR) and computed tomography (CT) to guide additive manufacturing (AM) technology. Methods: Images from 45 fetuses, including 4 sets of twins, were used. Twenty-three fetuses were normal and evaluated only by 3DUS. Twenty-two cases had complications such as conjoined twins; tumors; aneuploidy; skeletal; central nervous system; facial or thoracic defects. Scans were performed using high-resolution 3DUS. In cases of abnormalities, MR and CT were performed on the same day as 3DUS. The images obtained with 3DUS, MR or CT, were exported to a workstation in Digital Imaging and Communications in Medicine format. A single observer performed slice-by-slice manual segmentation using a digital high definition screen. Software that converts medical images into numerical models was used to construct virtual 3D models, which were physically realised using AM technologies (SLA Viper, Objet Connex 350, ZCorp 510 or FDM Vantage). Results: The main outcomes presented were the possibility to create 3D virtual and physical models from 3DUS, MRI or CT both separately and also in various combinations. AM systems allow the conversion of a 3D virtual model to a physical model in a fast, easy and dimensionally accurate process. They were remarkably similar to the postnatal appearance of the aborted fetus or newborn baby. Conclusions: This study introduced the innovative use of AM models into fetal researches. The results suggest a new possibility for educational purposes or better interaction between parents and their unborn child during pregnancy. Normal fetus (29 weeks): Virtual and physical model built in a powder-based system.