Hydrocephalus Treatment

The FDA approved the Aura(TM) wireless intracranial pressure monitor nearly two years ago. While that technology may ultimately give parents the ability to monitor their child’s intracranial pressure to help determine if a shunt is failing, it was only the beginning of the search for a “smart shunt.” Almost serendipitously, the development of the wireless intracranial pressure monitor coincided with a swell of groundbreaking hydrocephalus research taking place at the CHOC Neuroscience Institute.

Backed by a $2 million gift from the LeVecke Family Foundation, research in the newly named The LeVecke Family Foundation Hydrocephalus Center of Excellence has ramped up this past year. Those working with hydrocephalus know just how few researchers are in this field worldwide, so CHOC was very fortunate to recruit experienced hydrocephalus senior scientist Leandro Castañeyra-Ruiz, PhD, and electrical engineer Seunghyun Lee, PhD.

“The melding of their experience and skill sets enables us to do some really exciting things,” says Michael Muhonen, MD, pediatric neurosurgeon and medical director of The LeVecke Family Foundation Hydrocephalus Center of Excellence.

The fact is that the average person with a brain shunt will have to have it revised, on average, 10 times in their life. This stat is unacceptable to the team and they have made it their goal to cut that number to zero. The investigations currently taking place are not singular, nor are they linear.

Lines of inquiry (in vitro and in vivo) have been opened in collaboration with Anuncia and Medtronic to obtain clinically relevant data about the causes of occlusion in existing shunts. A grant has been obtained to develop a catheter-less fully passive miniaturized check valve. Pharmacological treatments are being evaluated to prevent hydrocephalus in order to understand the triggers for this condition and the underlying pathophysiology. A bioreactor system has been designed and built to test the mechanisms that underlay shunt obstruction under hydrocephalic conditions.

Studies are under way to learn more about the modulation of junctional complexes to prevent acquired hydrocephalus. To aid in the scope of these investigations, discarded cerebral spinal fluid from patients is collected, frozen and stored in the lab for future use. The fluid circulates within the brain model built by Dr. Lee. It has been discovered that once the fluid is thawed and warmed, its original physiological characteristics have been retained. The fluid is then pumped through the brain model, mimicking an in vivo setting, with a continuous flow of cerebral spinal fluid of 20 milliliters per hour.

Patients who require shunt surgery often have the old hardware replaced. The extracted hardware that has failed is now saved and brought to the lab to analyze the mechanism of failure. The catheters from the brain portion of the shunt are then tested to determine why they occluded, and how much pressure it takes to disocclude them. In addition to the catheters removed from patients, sterile ones are purposefully being occluded with cultured cells, thereby enlarging the database so that more catheters can be tested to determine why they occlude, the level of pressure required to clear a blockage and to better understand how to stop the occlusion from ever occurring.

Dr. Muhonen summarizes his view of the Hydrocephalus Center of Excellence: “As other physicians in the CHOC Neuroscience Institute have said, our research begins at the bedside where we ask ourselves every day, ‘How can we make our patients’ lives better?’ For us, that answer is, ‘By bringing the number of failed shunts down to zero.’”