Touching Lives - April 2014
Improving fetal MRI scanning: saving babies' lives
Action Medical Research has been funding research looking at babies’ development in the womb for more than 40 years. Recent funding helped a London team to develop specialised MRI scanning techniques, giving clearer pictures of babies who may be at serious risk.
Back in the 1970s and 1980s Action supported a number of projects to develop the use of ultrasound scanning techniques during pregnancy. Today ultrasound scans are routinely used across the world and this is estimated to have almost halved the death rate for babies at the time of birth.
But for some babies ultrasound scans alone are not enough to diagnose a suspected problem. When this is the case, magnetic resonance imaging – commonly known as MRI – has for many years been the method of choice to look more closely at a baby’s development, especially the brain.
However, while the pictures being produced were more detailed than ultrasound, MRI scanning techniques that worked well in adults proved much less effective when looking at babies in the womb. The problem was that it took a long time to take the images and the babies needed to stay still throughout – something that usually proved impossible!
If images are blurred or not clear enough, important abnormalities could be missed. Doctors needed to improve the quality of the pictures so that easier and more accurate diagnoses could be made.
Between 2006 and 2012 Action Medical Research funded two grants, worth more than £270,000, to Professor Mary Rutherford and her team, then based at Hammersmith Hospital in London. Their aim was to develop new fetal MRI scanning techniques to help improve diagnosis and treatments for unborn babies suffering from a range of conditions.
In their first study, Action funding helped develop methods to take multiple scans of babies’ brains and then slot them together to make clearer, more accurate 3D images. The new approach involved taking images of thinner ‘slices’ of the brain, which are automatically realigned to correct for the baby moving. Many pictures are taken and since more of the brain is seen, the diagnosis is more accurate.
The new 3D pictures meant doctors could also compare how different parts of the brain develop before and after birth, giving unique insights into how premature babies might be affected by their early arrival.
A second study began in 2010, funded by Action together with WellChild, and aimed to improve even more advanced MRI scanning techniques so that small sections in the brain, known as microstructures, could be studied.
These new techniques could highlight areas where movement of water in the brain tissues was restricted, perhaps indicating an area of abnormal development or recent injury. Doctors could create a ‘map’ of the growing brain, showing if a baby is at risk of brain damage due to reduction in blood flow and oxygen.
But the team needed to dramatically shorten the time it took to take these advanced scans. The technique is so sensitive that even a mother’s breathing could cause pictures to blur. It had previously taken one minute 43 seconds to take a picture. With Action funding they reduced this to just 23 seconds – the time a mother can hold her breath.
Such superior images can yield vital, sometimes life-saving, information that can determine treatment decisions – such as choosing to deliver a baby early or by caesarean section. They enable doctors to give more accurate diagnosis of development problems or injuries that could lead to conditions such as cerebral palsy or autism. They can also identify babies who may need immediate surgery after birth.
As well as the brain, other organs, such as the heart and kidneys, can also be studied in detail using the new MRI techniques. Many conditions that may be suspected from an ultrasound scan can now be confirmed.
Professor Mary Rutherford says: “Because of funding from Action we are in a position to diagnose many conditions more accurately and with more confidence while a baby is still in the womb. Fetal MRI is now being requested increasingly frequently and the technique would not be fit for purpose without the research that has been done.”
Around 300 babies a year are now being assessed at Professor Rutherford’s clinic (now based at St Thomas’s Hospital, London) and fetal MRI scanning is available in most large cities in the UK.