Exploring Emerging Technology in Focused Ultrasound

Hydrocephalus is a complex condition where excess cerebrospinal fluid (CSF) accumulates in the brain, increasing pressure and potentially leading to a range of symptoms—such as difficulty walking, memory problems, or headaches. While shunt systems and endoscopic third ventriculostomy (ETV) surgeries remain the standard treatment options today, researchers are exploring new, less invasive technologies that could improve outcomes or reduce complications.

One promising innovation is focused ultrasound—a technique that uses sound waves to precisely target areas of the brain. This approach may open the door to novel treatments that don’t rely on traditional surgery.

What Is Focused Ultrasound?

Focused ultrasound is a non-invasive technique that uses high-frequency sound waves to target specific brain structures with precision—without needing to make an incision. Think of it as using a magnifying glass to concentrate sunlight on a small area: focused ultrasound directs sound energy deep into the body to stimulate, disrupt, or modify tissue.

(Image source: Wang et al., 2020)

While ultrasound is commonly used for imaging (such as during pregnancy), focused ultrasound takes this a step further—delivering energy powerful enough to potentially produce therapeutic effects such as localized heating or the mechanical destruction of targeted tissues. It is currently being explored as a treatment for neurological disorders like Parkinson’s disease, essential tremor, breaking up brain hemorrhage blood clots, and now, hydrocephalus.

An Exploration: Focused Ultrasound in Hydrocephalus Research

Recent studies examine how focused ultrasound could benefit people living with hydrocephalus—particularly normal pressure hydrocephalus (NPH), a form often seen in older adults that causes problems with walking, bladder control, and thinking.

In a recent pilot study, researchers applied low-intensity focused ultrasound transcranially (meaning through the skull) to the brains of 10 individuals with NPH in order to stimulate CSF flow. After three sessions, participants showed clinically significant improvements in balance and walking speed. In the Timed Up-and-Go (TUG) test, patients’ time decreased by an average of 7.1 seconds (a 23.3% improvement). In the 10-meter gait (walk) test, their time decreased by an average of 5.9 seconds (a 21.0% improvement). Although these early results are promising, scientists emphasize the need for larger, controlled studies to determine whether this approach could become a treatment option.

How Might Focused Ultrasound Help?

Scientists are exploring several potential ways that focused ultrasound could support the treatment or management of hydrocephalus:

1. Improving Cerebrospinal Fluid (CSF) Flow

In hydrocephalus, CSF can build up in the brain’s ventricles, increasing pressure and damaging tissue. Early studies suggest that focused ultrasound may be used to help restore or improve CSF circulation—potentially by loosening blockages or stimulating natural flow mechanisms (Choi et al., 2024). In animal models, low-intensity ultrasound helped improve CSF flow in hydrocephalus-like conditions, laying the groundwork for future human trials (Seo et al., 2025).

2. Helping with Drug Delivery to the Brain

The blood-brain barrier protects the brain from harmful substances—but it also blocks many helpful medications. Focused ultrasound can temporarily open this barrier in a controlled way, making it easier to deliver drugs directly to brain tissue (Wang et al., 2020). For hydrocephalus, this could mean delivering targeted therapies that reduce inflammation, resolve blockages, or enhance CSF absorption.

3. Clearing Shunt Blockages

One of the most common complications in hydrocephalus management is shunt malfunction, often caused by blockages that prevent cerebrospinal fluid (CSF) from flowing properly. Read our blog on shunt occlusion here.

Researchers are exploring whether focused ultrasound could be used as a non-invasive way to help clear or prevent shunt obstructions (Gomez-Gonzalez et al., 2022). By directing ultrasound waves toward the shunt site, it may be possible to dislodge small particles from the catheter, restoring proper flow—similar to using vibrations to clear sediment from a narrow pipe.

If proven effective, this approach could reduce the need for revision surgeries and improve long-term outcomes for people with shunt-dependent hydrocephalus.

HA’s Investment in Supporting Innovation

While focused ultrasound is not yet a treatment for hydrocephalus, early studies are encouraging. Continued research will help determine if this technology can be safely and effectively integrated into hydrocephalus care.

In line with our top Community Research Priority of developing non-invasive and one-time therapies, the Hydrocephalus Association with support from Team Hydro funded Dr. Jonathan Sukovich the 2023 Innovator Award for his research project titled “Histotripsy for the treatment of hydrocephalus”. Dr. Sukovich is a member of the Histotripsy team at University of Michigan, who also won the 2023 Distinguished University Innovator of the Year Award for the development of histotripsy technologies. Histotripsy is a method that uses high intensity focused ultrasound to generate microbubbles inside targeted tissue to mechanically destroy and liquefy affected tissues. Recent studies have demonstrated the ability of histotripsy to create targeted lesions in the brain, in in vitro (cell/tissue) and human cadaveric models, without requiring surgical incisions (Sukovich et al., 2024).

Dr. Sukovich’s current study tests the use of this method as a non-invasive treatment for hydrocephalus. Histotripsy offers the potential to non-invasively perform ETVs by creating a small hole in the third ventricle to allow for drainage of excess CSF, or to destroy regions of the choroid plexus to reduce the production of CSF at its source. Histotripsy also has to the potential to be used for liquefying tissue blockages within shunts, without making surgical incisions, to restore proper flow through these devices.

For individuals and families affected by this condition, continued research on focused ultrasound represents a step toward less invasive and more personalized treatment options for hydrocephalus.