4D scan

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#818.03.2007, 00:10

BMJ 2007;334:232-233 (3 February), doi:10.1136/bmj.39106.494931.94 <?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" />FeatureOne for the albumFirst picturesOne for the album Geoff Watts, freelance journalist 1 London Expectant parents' desire to see images of their unborn children has given rise to private ultrasonography services. Geoff Watts considers whether this non-medical use of the technique can be justified The pictures tell the story. Baby's first feed, first smile, first steps, first birthday, first everything. The record is there to be scrutinised and treasured. But why wait until birth? Why not start this pictorial history in utero? Ultrasound imaging may have entered obstetrics as a medical tool, but it is now establishing itself as something much more. Go to the web and you can find scores of companies willing to exploit the powerful emotional impact of seeing your fetus by generating still pictures to grace the first page of the album or moving ones to play on the home computer. Not medically necessary, of course. An indulgence, certainly, but harmless. Or is it? Not everyone takes a benign view of non-medical ultrasonography. The US Food and Drugs Administration, the American Institute of Ultrasound in Medicine, and the French Academy of Medicine are among several official bodies that have reservations about such use of the technology. In the United Kingdom, Dr Paul Sidhu, chairman of the scientific and education committee of the British Medical Ultrasound Society, detects what he describes as an "overall sense of disapproval" among his colleagues for this development. What was once the casual offer of hazy black and white Polaroid images during a routine antenatal scan has become a slick business transaction. Driving this transformation has been the big improvement in ultrasound technology. The early two dimensional black and white scans gave a succession of poor resolution slices through the womb and its contents. Better technology sharpened the images. Then machines arrived that could assemble the slices into a 3D picture of the whole fetus with improved resolution and added colour. With the advent of the fourth dimension— time—the unborn child can be seen moving. The images are without question startling and, to a parent, captivating. Many of the companies offering 3D and 4D scans publish testimonials. The Babyview website, for example: "The experience was out of this world ...The most overwhelming feeling in the world to see baby smile ... Probably the best hour of our lives ... Thank you for the amazing experience." The word "amazing" crops up again and again. Expectant parents seeking a CD-ROM or a DVD of their scan can expect to pay £150-£250 (<?xml:namespace prefix = v ns = "urn:schemas-microsoft-com:vml" /> 230- 380;$300- $490). Some critics regard the advent of this "boutique ultrasonography" as yet another step towards the medicalisation of birth.1 But this view is hard to sustain. Keepsake imaging is, if anything, about the demystification of medical technology. And if people choose to pay a couple of hundred pounds to undergo a safe imaging technique, why shouldn't they? No reason at all—so long as it really is safe. This, of course, is the nub of the argument. Medical concernsThe commercial providers are reassuring. "During the 30 years or so since the introduction of ultrasound in obstetrics," according to Babyview (www.babyview.co.uk/faq.asp) "it has not been proven to cause harm." In similar vein, Create Health (www.createhealth.org/dimensional.html) says: "Despite extensive studies over 30 years ultrasound has not been shown to cause any harm to mother or baby." The FDA is more cautious: "Although there is no evidence that these physical effects can harm the fetus, public health experts, clinicians and industry agree that casual exposure to ultrasound, especially during pregnancy, should be avoided."2 The important distinction here is the familiar one between "absence of evidence" and "evidence of absence." The argument is not confined to Britain. Guillaume Gorincour is a radiologist specialising in prenatal diagnosis at Timone University Hospital in Marseilles. He worries about the growth of commercial keepsake scanning companies operating in France without medical supervision. How, he wonders, do staff deal with the discovery of a fetal abnormality? "Will they announce the bad news to the parents? Or will they say nothing?" Some contracts, he adds, specifically rule out the delivery of any medical information. Also, the ill judged breaking of bad news can influence parents' decisions on whether to continue with an affected pregnancy. Unlike some doctors working with ultrasound, Dr Gorincour has no inherent objection to generating keepsake images. "After we have performed ultrasound for medical reasons, we try to provide a good 3D picture of the face for the parents, as an extra service. From the medical point of view, 3D or 4D doesn't add any diagnostic information. But humans are not machines. People want to see their baby." In the US, the FDA has long been opposed to non-medical ultrasonography. In the mid- 1990s its Center for Devices and Radiological Health2 began investigating several companies that were doing ultrasonography without medical authorisation or supervision. This, it points out, "may be in violation of State or local laws or regulations regarding use of a prescription medical device." In 2002 it announced that anyone administering ultrasound without a prescription is breaking the law. But what of non-medical keepsake scans that are taken with the authorisation of a doctor? The FDA clearly takes a dim view of this too but seems not to have decided precisely what, if any, action to take. The American Institute of Ultrasound Medicine, by contrast, tackles the issue head on. In a statement issued last August it acknowledged the pressure from patients for keepsake scans.3 It then distinguished between three different circumstances in which expectant mothers might be given a keepsake scan:

As the byproduct of a medically indicated ultrasound examination
Through a commercial fetal imaging organisation operating without medical supervision
Through a medical facility operating beyond the medically necessary use of ultrasonography.

The institute concludes that only the first of these three scenarios is consistent with "the ethical principles of our professional organisations." The second is unacceptable by virtue of the absence of medical supervision, while the third runs counter to the American Medical Association's code of ethics. This states: "The sale of non-health-related goods by physicians presents a conflict of interest and threatens to erode the primary obligation of physicians to serve the interests of their patients before their own ... Physicians should not sell non-health-related goods from their offices or other treatment settings." The British Medical Ultrasound Society does not, at the moment, have a specific policy on keepsake ultrasound scans. What it does have, says Dr Sidhu, is a policy on safety. This follows the ALARA principle (as low as reasonably achievable). The society is currently updating its policy, and the new version will probably include a statement on non-medical imaging. This is unlikely to be more permissive than that of its US counterpart. One of the leading exponents of ultrasonography in the UK is Professor Stuart Campbell, now retired from the health service and working with Create Health. He is not impressed by the safety argument. He points out that doctors in training, who haven't yet mastered an efficient ultrasound technique, subject pregnant women to much greater doses than would a skilled operator. "Nobody bats an eyelid about that," he says. If people were seriously worried about scanning time they would develop computer simulations on which doctors could practice their technique. "If you are competent at what you're doing, the extra five minutes [required to generate a keepsake scan] is absolutely negligible." BondingBeyond spreading a little happiness, the case for non-medical imaging relies principally on bonding: the sense of attachment between a mother and her unborn child. The evidence that ultrasound images can foster this comes from 2D scans.4 5 But what of the newer technology? "3D or 4D doesn't add anything more than classical 2D ultrasound in creating the mother's emotional attachment," according to Dr Gorincour. Indeed, a recent study found no evidence that 3D was more effective in enhancing maternal-fetal attachment in scans performed at 12 and 18 weeks.6 Professor Campbell is conscious of the lack of firm evidence, and accepts that his enthusiasm may put him in a minority. But he continues to speak with passion about "the excited response of parents," especially fathers, when they see the image on the screen. He would like an assessment of the effect of 4D imaging in the third trimester.7 This, he suspects, would show the full effect of the technology. At present, he believes, "most doctors are embarrassed by the concept of bonding. They just want to do their examination and move on." The controversy over 3D and 4D imaging would be partially resolved if genuine medical utility could be shown. As Dr Sidhu points out, research is currently under way to find out if seeing the fetus in 3D might help spot abnormalities such as cleft lip. "Early indications are that it probably is a little bit more useful." But for the moment, he adds, it is by no means self evidently beneficial. "It produces pretty pictures. But people who've been using ultrasound for many years and can understand images in 2D can get very good results from just that." There is, of course, one group that's anything but dismissive about "pretty pictures": the pro-life movement. Many women and the partners, according to one Christian magazine, "change their minds about aborting their child when they see their child's image on the sonogram screen."8 The headline that appeared a few months ago on a (now defunct) US Catholic website said it all: "GE's new 4D ultrasound technology: a wonderful tool for the pro-life fight."

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