Researchers at the University of Pennsylvania have developed a novel method for monitoring oxygen levels of the placenta, potentially aiding in the early detection and diagnosis of complications that can arise during pregnancy.
The placenta, which serves as a link between a mother and foetus, plays a crucial role in delivering oxygen and nutrients. Abnormalities in the supply of either of these can lead to impairment in the placenta’s functioning, leading to neurological and congenital cardiac conditions in newborns.
The technology, developed after three years of intensive research, combines optical measuring techniques with ultrasound to peer deeper into tissues than is currently possible with real-time monitoring technologies. The results were published in peer-reviewed publication Nature Biomedical Engineering.
“We’re sending a light signal that goes through the same deep tissues as the ultrasound. The extremely small amount of light that returns to the surface probe is then used to accurately assess tissue properties, which is only possible with very stable lasers, optics, and detectors,” says Arjun Yodh, professor in the Department of Physics and Astronomy at the University of Pennsylvania.
One of the biggest technical hurdles that the team dealt with was improving the quality of data generated by the opto-electronic system as the placenta is situated deep within the body. As light passes through dense tissues, it gets scattered and absorbed, making it hard to get an accurate reading.
To get over this they developed advanced programming and algorithms to ensure that the meagre amount of light being reflected by the body tissues inside the placenta would still provide a high-quality measurement.
The technique allowed them to measure the oxygen levels in the placenta in real time up to 4.2 cm below the surface of the body. They validated the functioning of the device by testing it on 24 pregnant mothers in their third trimester by supplementing them with oxygen for a short time and looking at the results.
“Not only do we show that oxygen levels go up when you give the mom oxygen, but when we analyse the data…patients with maternal vascular malperfusion did not have as much of an increase in oxygen compared to patients with normal placentas,” said Nadav Schwartz, associate professor in the Department of Obstetrics and Gynecology at the Perelman School of Medicine.
Maternal vascular malperfusion is a condition in which the functional capacity of the placenta is impaired due to altered maternal blood flow.
The technology could serve as a major improvement over current diagnosis techniques that use an MRI or doppler scan. These cannot be used in real-time monitoring scenarios, and under certain circumstances recurrent scans may prove intrusive for the foetus.
If successfully tested, validated and rolled out, the new diagnostic technique could be used to find abnormalities in the supply of oxygen and nutrients through the placenta, cutting down the risk of fluid retention in a developing foetus and even stillbirth.
