Researchers from Ohio State University and Harvard University in the USA have come up with an innovative solution to reduce the risks of neurosurgery complications. The team developed a tough bioadhesive hydrogel called dural tough adhesive (DTA) that offers better sealing of the brain’s protective layers following neurosurgery, allowing for a suture-less repair.
A common challenge after neurosurgery is the leaking of cerebrospinal fluid (CSF) from the dura – the outermost protective layer of the three meninges enveloping the brain and spinal cord. CSF leakage can impair neurological functions or recovery after a neurosurgery. Sometimes, it can also be life-threatening.
“As neurosurgeons, we routinely open the dura to access the brain or spinal cord, but achieving a watertight seal of the dura after these procedures can be challenging in some circumstances,” said Dr Kyle Wu, a neurosurgeon and assistant professor at Wexner Medical Centre, Ohio State University, in a statement.
The new gel overcomes the limitations of current methods, such as suture repair or grafting, which can be challenging to perform if there is no viable tissue, the dura has significant defects, or during minimally invasive surgeries. “Although still in the very early stages of clinical translation, the clinical trial could begin in a few months depending upon approval from the FDA,” Dr Wu told Happiest Health.
Currently, available surgical sealants do not adhere well to wet tissue, are too brittle, and lack the requisite toughness to prevent CSF leakage reliably, Dr Wu added.
The study published in Science Translational Medicine on 20 March shows that DTA outperforms other commercially available sealants in wet environments by creating a watertight seal at the sites where the dura is opened and enduring stress and stretching caused by CSF pressure.
The strength of two
DTA is a mix of two polymers that provide high elasticity and toughness. The combination material endures the mechanical force of the underlying tissues and has a chitosan-based adhesive layer. Chitosan—a fibrous substance found in shellfish exoskeletons—combined with the composite hydrogel forms multiple chemical interactions to bind with various liquid-covered surfaces. The result is a tight seal.
The high mechanical strength is an essential property of DTA, which endures high intracranial pressure observed in conditions such as stroke or brain tumours.
The authors demonstrated the durability of DTA in rats and pigs. The gel withstood artificially generated intracranial pressures in human-derived tissues well beyond those found in disease conditions and adhered better than current sealants.
DTA was found to be biocompatible when placed directly on the dura of live rats. It maintained its structure for four weeks with minimal reactions.
Looking ahead
“We are excited to have opened a new perspective for neurosurgeons with this study that, in future, could facilitate a variety of surgical interventions and lower the risk for people who need to undergo them,” said Dr David J Mooney, professor of bioengineering, Wyss Institute for Biologically Inspired Engineering, Harvard University. He added that their study highlights how improved biomaterials can affect different areas of regenerative medicine.
