Fetal imaging: past, present, and future. A journey of marvel

Abstract

The fetus has always been an enigma to artists and scientists alike, enthralled by the mysteries of developing human life. Prior to the availability of fetal imaging, they were relentless in their pursuit to get a glimpse of, and a better understanding of, the developing fetus. From Da Vinci's sketches, depicting the fetus within a cadaver in the 1510s, to Hunter's Anatomia Uteri Humani in 1774, where he resorted to fetal etchings from pregnant human cadavers, we have humanity's earliest documented preserved fetal images. In 1794, two decades after Hunter, Lazzaro Spallanzani discovered that bats use 'echolocation' to travel in the dark, thereby laying the foundations for the physics of ultrasound. It took another 148 years for Dussik to pioneer diagnostic ultrasound, in 1942, by transmitting ultrasonic beams through the head in order to diagnose brain tumours. In 1952, the American Institute of Ultrasound in Medicine was founded (see the History of Ultrasound at http://ultrasoundschoolsguide.com/history-of-ultrasound/). In fetal medicine, the earliest forms of 'modern' imaging were roentograms, first used in the early 20th century. Although the risks were well noted, the utility in diagnosing pregnancy, determining the number of fetuses and uterine lie, and in diagnosing skeletal dysplasias were recognised and reported on. Four decades later, the revolution of obstetrical sonography, a safe modality, commenced with the pioneering work of Ian Donald (BJOG 1965;72:907–19; 1968;75:993–1006) and Stuart Campbell (BJOG 1965;75:568–76), with the first reports on cephalometry and placentography. Obstetrical practice was never to be the same; over the past 50 years, it has witnessed unfathomable progress facilitated by the technological advances. From Benacerraf's nuchal fold to Nicolaides' nuchal translucency and the first-trimester scan, sonography is our primary modality for screening and diagnosing major fetal and maternal conditions. The International Society of Ultrasound in Obstetrics & Gynecology was consequently founded in 1991. Most recently, with the introduction of 3D sonography in the 1980s, and Abuhamad's automated multiplanar imaging, standardised automated scanning of the most complex of organs, the fetal heart, is now a reality. In addition, with the availability of electronic transducers, the drastic improvement in the resolution of our images is clearly visible (Figure 1). Despite other emerging technologies for imaging the fetus, with magnetic resonance imaging at the forefront, ultrasound remains the primary modality because of its safety, affordability, and portability: hand-held devices have taken our diagnostic capabilities out into any field, and as far out as outer space. Where to next? The future has unlimited potential as the technology continues to evolve. Its role in the study of fetal anatomy, in the era of cfDNA testing, shall critically move into the first trimester, and our pendulum shall shift from the study of structure to the study of function. With vision, leaders in the field are now consecrating all efforts towards the standardisation of training (Abuhamad, JUM 2018;37:19–50), in order to ensure quality and to maximise the diagnostic capabilities before the point of full automation is reached. The future is most promising and exciting – if only one were to be given the life to be able to bear witness to the unravelling of this journey of marvel… None declared. Completed disclosure of interests form available to view online as supporting information. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.