Researchers from the University of São Paulo in Brazil, the University of Cambridge in the United Kingdom, Emory University in the United States, and the Brazilian company brain4care recently presented a technology that can measure intracranial pressure (ICP) absolute values more accurately than existing non-invasive techniques in a study published in the journal npj Digital Medicine.
The technology consists of a sensor placed on the patient’s head that registers the nanometric expansions of the skull in each cardiac cycle and generates, in real time, a wave that indicates the variations in volume and intracranial pressure. Image Credit: brain4care
The study included the largest number of patients and showed that the technology we developed had the lowest error in estimating the value of intracranial pressure among all the non-invasive methods already available in the world.
Gustavo Frigieri, Scientific Director and Study Author, University of São Paulo in Brazil
With the help of FAPESP's Innovative Research in Small Businesses Program (PIPE), the Brazilian company developed a technology that uses a sensor on the patient's head to record the nanometric expansions of the skull during each cardiac cycle.
The sensor then creates a wave that shows changes in intracranial pressure and volume in real-time. An artificial intelligence platform processes the collected data and produces reports to assist physicians in making decisions.
Frigieri claims that the brain4care solution differs from traditional methods in the three primary components of ICP analysis: the numerical value, the trend (up or down), and the pulse's morphology. Instead of focusing on the numerical value, this method evaluates the pulse's morphology—that is, how it behaves over time. This method enables the identification of changes before they appear in the pressure's numerical values.
This understanding has been consolidated worldwide. Invasive ICP is reactive, and brain4care is proactive because it allows us to act in advance. Still, physicians are used to the number, which comes in late, meaning that they only act when there are changes in the patient. Our technology already provides the morphology and trend of the ICP and is moving towards showing the absolute number.
Gustavo Frigieri, Scientific Director and Study Author, University of São Paulo in Brazil
The company's researchers converted the ICP pulse into numerical values as part of the system development process.
Gustavo Frigieri said, “We show the physician the patient’s situation so he can decide how to proceed. In the articles we have published, we have shown that the pulse is very important and that it does the same thing as an invasive ICP measurement but in a non-invasive way. It allows the physician to see if the patient is getting worse or better based on the trend.”
In critical cases, the system can make the difference between life and death because it allows doctors to identify neurological changes early and take more prompt, precise action.
Frigeri pointed out, “The longer a neurocritical patient goes without proper care, the greater the risk of sequelae. I provide the sensor and train the professional to make treatment decisions and achieve the best outcome.”
Proven Effectiveness
More than a hundred published scientific articles have demonstrated the brain4care method's efficacy. The new study enrolled patients from Brazil, the US, and Europe.
Frigeri said, “We accelerated the process of collecting this information, and today we have a very interesting database of patients with invasive and non-invasive ICP. Using a machine learning model, we were able to estimate the value of ICP in these patients.”
Frigeri continued, “We were able to achieve an error of 3 mm of mercury [the means by which ICP is usually measured] in more than a hundred patients. Many researchers are looking for non-invasive ways to measure ICP, but the techniques used have a very large error, which makes the system not ideal for clinical use.”
After demonstrating in the lab that the estimate can be made, Frigieri keeps trying to gather solid proof.
I currently have 168 patients in the database, and I have already reduced the error to 2.6 mm of mercury. The goal is to consolidate the model later this year to demonstrate in the field that, in addition to morphology and trend, brain4care can provide the number doctors are looking for. We have already shown that it is possible to derive ICP from morphology in a completely non-invasive way. The next step is to make this a reality for the market.
Gustavo Frigieri, Scientific Director and Study Author, University of São Paulo in Brazil
According to Frigieri, the technique can help any neurosurgery patient at risk of bleeding. This is because the doctor frequently acts almost blindly when the patient is sedated and ventilated in an intensive care unit (ICU), such as when he performs a CT scan after the procedure and repeats it 24 hours later.
Frigeri said, “In these cases, you can use brain4care every two hours and, if things get worse, add a CT scan to see what happened in more detail.”
One of the gadget's benefits is its adaptability. In addition to the intensive care unit, it can be utilized in emergency rooms, outpatient clinics, and medical clinics. This makes ICP monitoring much more accessible. In cases of head trauma, where every minute counts to preserve brain function, prompt diagnosis and treatment are essential.
He claims that brain4care is simple to use and does not require intricate training.
Frigieri explained, “It can be adapted to the scenario. For example, if you just need to check whether the patient has intracranial hypertension, 5 to 10 minutes of use may be enough. A more unstable patient, on the other hand, can wear the device for an hour or two for longer monitoring.”
Portable Equipment
The researcher claims that the patient must be taken to the operating room to implant the device using the invasive ICP monitoring method. On the other hand, Brain4care is portable.
Frigieri said, “I always say that we are not going to replace invasive ICP, but we will be able to determine who really needs it. We want to make sure that the majority of patients are treated before they become critical, but that those who need this type of intervention can receive it safely. At the same time, this will help to optimize the use of resources.”
Brain4care is available in over 85 Brazilian institutions, ranging from small charity hospitals in rural areas to prestigious hospitals in São Paulo. This broad distribution shows how flexible the system is to various requirements and situations. Concurrently, the business is growing abroad; it has been operating in the US since 2018 and has been formally marketing since last October.
“We have gone the other way: we are exporting medical technology around the world. We have a company in the United States that is a subsidiary and distributor, but all the intelligence and production is Brazilian,” Frigieri said proudly.
The Food and Drug Administration (FDA), the US equivalent of the Brazilian National Health Surveillance Agency (ANVISA), which oversees therapies, medical technologies, and pharmaceuticals, has already approved the technology.
Furthermore, 128 scientific studies have already been made possible by it; some of these have been finished, while others are still ongoing. The method's non-invasive nature enables research that would be impossible with conventional methods, advancing our understanding of several medical specialties.
Researchers from various specialties have been drawn to this feature and use the data collected by brain4care in other scientific studies.
Frigieri said, “Previously, this information was not available for scientific use. The arrival of brain4care has opened up opportunities for the development of knowledge.”
Journal Reference:
Frigieri, G., et al. (2025) Machine learning approach for noninvasive intracranial pressure estimation using pulsatile cranial expansion waveforms. npj Digital Medicine. doi.org/10.1038/s41746-025-01463-y.