Researchers from the University of Birmingham in the UK have developed a modified laser treatment that results in better outcomes for babies affected by a condition called twin-twin transfusion syndrome (TTTS).
The study, published in medical journal The Lancet in March, demonstrates how the new approach, called the Solomon method, can dramatically reduce both the recurrence of TTTS and disabilities which may occur as a result of the condition. Due to the work, the approach will now be used as the clinical standard.
TTTS is a condition which occurs in one in eight identical twin pregnancies where the foetuses share a single placenta. In this condition, some blood vessels on the surface of the placenta join the circulations of both babies, leading to one baby receiving too much blood and developing high blood pressure, while the other does not get enough.
If left untreated, the vast majority of babies – more than 90 per cent – will die, and, of the survivors, 80 per cent will suffer from severe disabilities.
The usual treatment is to selectively coagulate the blood vessels with a laser to stop the flow of blood between the two babies. However, this treatment, although leading to the live birth of at least one twin in 85 per cent of cases, can leave miniscule blood vessels in place, which leads to the condition reoccurring, or another rare condition forming, called ‘twin anaemia/polycythemia syndrome (TAPS). Such babies are often delivered very prematurely and are at significant risk of disability.
The Solomon technique developed at Birmingham University involves lasering the entire placental vascular equator; that is, lasering the blood vessels, but then also a circuit around the placenta in a bid to try to sever any tiny blood vessels which are not visible but may cause problems after treatment.
Professor Mark Kilby, professor of fetal medicine at Birmingham University’s College of Medical and Dental Science and Centre for Women’s and Children’s Health, and director of the Fetal Medicine Centre at Birmingham Women’s NHS Foundation Trust, worked on a collaborative randomised controlled trial with experts from five centres in Europe, to compare the Solomon technique and a more conventional laser therapy treatment.
Although the number of babies who died was similar for both treatments, the Solomon technique led to fewer babies being born with severe complications that could lead to disability – 8 per cent rather than 13 per cent for the conventional treatment. Just 1 per cent of the 137 women who were treated with the new technique then suffered a recurrence of the TTTS, compared to 7 per cent of the 135 women who were treated with the more conventional lasering. And, just 3 per cent of women undergoing the Solomon technique developed the related condition of TAPS, compared to 16 per cent in the conventional treatment group.
The Solomon technique will now become the clinical standard technique, and will reduce the incidence of TTTS returning and hopefully, the incidence of twins having to be delivered so early in the pregnancy.
Prof Kilby said: ‘This study was collaboration between experts in Europe and has led to the modification in treatment of a rare disease affecting identical twin pregnancies. It is a major step forward in the treatment of twin-to-twin transfusion syndrome. Although this treatment often leads to babies surviving, there have always been concerns that the babies would be born with handicap. The Solomon techniques minimises these risks.’