THREE DIMENSIONAL ULTRASOUND AND MULTIPLANAR
ULTRASOUND IN THE FIRST TRIMESTER OF PREGNANCY

Our experience.

The first studies in 3D ultrasound applied to the first trimester were carried out in Spain by Bonilla Musoles, who highlighted how this method improves the possibility to examine the result of conception in this period. The examinations carried out using three transvaginal scans allowed the early diagnosis of cases of meningocele and encephalocele, by improving the graphics of the information provided by the ultrasonographic signals. The first studies in Italy were carried out by Dodero and Sirito in collaboration with our group. These have shown how the acquisition of transvaginal ecographic volume reduces the time needed to examine a patient. The measurements acquired were then stored on a 88 MB Syquest disc. The patient was thus examined transvaginally for a time equal to the acquisition of the measurements (about 8 to 12 seconds). Subsequently it was possible to recall the volume and examine the data or send them to an external examiner. The availability of reliable and high-capacity hardware and software tools has allowed us to reduce by 150 times the time needed for the acquisition and manipulation of the computerized information (reformatting). The latest improvement in the mechanics of probe translating (vaginal and abdominal) and the introduction of digital systems – which have replaced the analogical ones – have considerably improved the examination of significant volumes.

Pregnancy at 8 weeks 5 days gestation. Transabdominal volume examined by multiplanar rendering. CRL of the fetus is measured on the sagittal scan (A).

Fig. 01b Same case as above. Moving the volume in a different way it is possible to see the vitelline sac.

Fig. 01c Same case as above. Rendering 3D.

Fig. 01-bis Pregnancy at 9 weeks and 6 days. Rendering 3D of fetal.

Fig. 02a 002a Pregnancy at 11 weeks and 5 days. The volume is reformatted in order to visualise fetal sagittal scan on plane A: measurement of the CRL.

Fig 02b Same case as above. Rendering 3D.

Fig. 03a Bi-chorionic bi-amniotic twin pregnancy at 8th weeks gestation.

Fig. 03b Pregnancy at 8 weeks. Bicorionic biamniotic twin pregnancy.

Fig. 04a Pregnancy at 11 weeks and 5 days gestation. The volume is placed and magnified: nuchal translucency in measured in plane A (sagiptal scan).

Fig. 04b Pregnancy in 13th week. Transabdominal volume. Pathologic nuchal translucency in fetus affected by hygroma.

Fig. 05 Pregnancy at 5th week gestation. Transabdominal volume examined multiplanar rendering. Arcuate uterus.

Fig. 06 Pregnancy at 5th week gestation in sub-septate uterus. Transabdominal volume examined with multiplanar rendering.

Fig. 07a Pregnancy at 7th week gestation in septate uterus. Transabdominal volume examined by multiplanar rendering.

Fig. 07b Same case as in previous figure. 3D rendering. The red arrows show the two parts of the uterus separated from the septum.

Fig. 08 Cervical pregnancy at 5th week gestation.

Fig. 09 Same case as above. Magnification of pregnancy in cervix.

Fig. 10 Pregnancy at 10th weeks gestation. Transabdominal volume examined by multiplanar rendering. The red arrows show a large area of amnio-corial detachment.

Fig. 11 Pregnancy at 13th week gestation. Transabdominal volume examined by multiplanar rendering. Anencephalic fetus. Click on MOVIE.

Fig. 12 Pregnancy at 12nd week. Transvaginal volume examined by multiplanar rendering. Exencephalic fetus.