Abigail Ringer writes about the potential benefits of the new MRI scanner installed in a Sheffield hospital, which is able to provide images of the brains of premature babies.
I have just finished reading about a miniature MRI scanner for imaging the brains of premature babies. The scanner, which took 12 years to develop, is now installed at the maternity hospital in Sheffield and the brains of more than 40 babies have already been viewed at the hospital. Professor Griffiths, who helped develop the scanner, is particularly excited about the difference it could make for babies.
The brains of newborn babies are normally scanned using ultrasound. An ultrasound machine passes sound waves on to the brain. The waves hit the brain and bounce back like an echo. The machine then turns this echo into a moving image that can be viewed by a doctor. In adult brains, ultrasound is not possible because the bones of the skull get in the way of the sound waves.
In newborn babies, however, the bones of the skulls have not yet completely fused together and the sound waves can be passed between the gap between the bones at the top of the head. This gap, or fontanelle, is like a little window in to the brain. Because the window into the brain is small, there are parts of the brain that can not be visualised through ultrasound. For example, the back of the brain is difficult to see and it is possible to miss injuries to this part of the brain.
The advantage of using magnetic resonance imaging, or MRI, over ultrasound scans, is that it is possible to visualise all of the brain. It also provides a clearer image for some types of injuries.
Professor Griffiths, who helped to develop the machine, describes the benefits: “Ultrasound is cheap, portable and convenient, but the position of the fontanelles means that there are some parts of the brain which cannot be viewed.
MRI is able to show all of the brain and the surrounding anatomy, making the images easier to explain to parents. From a diagnostic point, the big advantage is that MRI is able to show a wider range of brain abnormalities, in particular those which result from a lack of oxygen or blood supply.”
This new MRI scanner in Sheffield will therefore provide opportunity for the brains of premature newborn babies to be scanned at an early stage following their birth. This may provide the medics treating them with wider information about potential injuries to their brains than may have been possible with ultrasound scans. This information can then be used to guide their treatment requirements and to advise parents about their baby’s condition and prognosis.
My colleagues and I work with children who have been affected by brain injury – often injuries that have resulted from a lack of oxygen or blood to the brain at the time of their birth. A shortage of blood or oxygen may arise from incidents such as cord prolapse, where the umbilical cord becomes squashed and the supply of oxygen rich blood to the baby is shut off; or when the baby is not delivered quickly enough after beginning to show signs of distress. We work with expert radiologists, to examine images of the brain which, together with other information, can provide valuable information as to the nature of the injury and the timing of when the injury occurred – this is important to determine whether an injury was avoidable. At present there can be a lack of clear imaging from when a baby is newborn and these MRI scans may make it easier to determine the nature of the brain injury, and when an injury occurred, more accurately.
At the moment the tiny MRI scanner is only being used for research rather than for clinical practice. It is hoped that if the benefit of the scanner can be proved, then doctors would be allowed to use it on a routine basis in the future.
Professor Griffiths describes his motivation to continue with the project as “a belief that at the end we will have something that is better for babies with these types of brain problems”; a motivation that I wholeheartedly endorse. The scanner in Sheffield is one of only two in the world. I hope that in the future, similar mini scanners will be in maternity units all over the world so that more families will be able to make use of its benefits.