There are several new and emerging strategies for the delivery of care and achievement of better outcomes for traumatic brain injury (TBI) patients, including assessment and imaging of cerebrovascular functioning, inpatient and outpatient rehabilitation, multimodality monitoring, brain hypoxia management and resource utilization. Patient-specific therapies based upon ICP and other criteria are becoming important in the ICU setting. The implementation of the electronic medical record is an important advancement. It is estimated that 50 million people in the United States live one hour or more from a trauma center, so access to specialty care remains paramount. Current initiatives and involvement of Trauma Section members and leadership include projects with brain death criteria, evaluation of the issues surrounding cerebral edema and its treatment as well as the development of a severe TBI treatment algorithm, the latter led by Randall Chestnut, MD, and Gregory Hawryluk, MD, PhD, FAANS, and their steering committee.
Clinical research continues to be active and relevant for concussion, as it continues to remain an important and current topic in civilian life, for military service members and for athletes. Sports concussion continues to be on the forefront of clinical and laboratory research, and the involvement of neurosurgeons is paramount to improvements in understanding the pathophysiology and patient management. The diagnosis of concussion remains elusive, as it ordinarily is a subjective presentation and there are no outward or visible signs of injury. The diagnosis of concussion remains one of the most challenging tasks facing the clinician, and emerging technologies are implementing oculomotor function assessment, electroencephalography network patterns, brain pulsatility and other methods. A recent study by Adrian et al. utilized the biomarkers UCHL1 and GFAP to predict the presence of intracranial lesions on CT scans, representing the first FDA-approved blood test to document a mild TBI. This technology is not, however, a concussion test nor is it approved for use in pediatric patients.
New techniques are emerging for the management of traumatic intracranial lesions. Chronic subdural hematoma (cSDH) appears to be an increasingly encountered lesion as the population ages and the use of newer oral anticoagulation agents has increased. cSDH is usually defined as a collection of blood in the subdural space that is isodense or hypodense to the brain on CT imaging. While the duration is often unknown, it is thought that this represents a three-week or longer process, and frequently there is superimposed acute bleeding within the cSDH. For example, (MMA) embolization is now being used in some centers for treating cSDHs. A cSDH may increase in size or persist over time, even in the post-operative period, related to chronic inflammation and angiogenesis. Surgical intervention is usually undertaken when indicated by symptoms and clinical findings and newer therapies have involved medical strategies to change the osmotic environment, reduce inflammation (steroids) and others. MMA embolization has recently been promoted in an attempt to devascularize the subdural membranes so that continued leakage of blood products is reduced and the balance tends toward resorption. Several recent reports show that the patient may benefit by having this procedure performed.
We must remember that the pursuit of science in neurotrauma is vitally important for advances in the field as well as for optimal patient care and outcomes. There has been pessimism during the past several decades on the heels of numerous failed clinical trials for TBI intervention and the discovery of a universal therapy seems unlikely. Hypotheses about the role of genotype in disease can be tested in human models, but only if the disease pathology can be reproduced in vitro. Special tools are needed, since TBI depends intrinsically on a mechanical insult.
In my lab, we are working with an in vitro assay using patient-specific neurons created through stem cells from blood samples. The goal of reproducing the pathophysiology of TBI in vitro requires special tools to assess the changes that occur, such as using a multi-electrode array for field recordings of electrical activity and connectivity. By using brain organoids, we hope to overcome limitations of 2-D and single neuron models. Recent NIH funding should allow us to further explore this technique as applied to phenotypic-specific responses to injury and therapeutic interventions. New approaches have led to efforts for more individualized methods resembling the personalized care and genetic analysis, which has led to advances in other areas of medicine.
The Trauma Section continues to be on the cutting edge and very relevant to our members and the public as well as the communities we serve with these and other initiatives.
Julian E. Bailes, Jr., MD, FAANS
Chair, AANS/CNS Section on Neurotrauma and Critical Care