Thalamic Low Intensity Focused Ultrasound in Brain Injury

Few neurological conditions are as scientifically mysterious and clinically, legally, and ethically challenging as disorders of consciousness (DOC). Typically developed after severe brain injury, this set of related conditions includes Coma, the Vegetative State (VS) and the Minimally Conscious State (MCS). In the past 20 years, an increasing amount of research has broken many conventions about these disorders, including the once widespread belief that these patients are entirely apallic - that is, lack any kind of "higher" activity. Since then, it has been shown that a lot of brain activity, including relatively high-level cognitive processes, can remain in DOC patients. Nonetheless, to date there exists no standard intervention for patients suffering from these devastating conditions. Developing interventions for this population is extremely important first and foremost for the well-being of patients, who - today - remain completely dependent on assisted care, are often unable to participate in rehabilitative programs because of their lack of behavioral responsiveness, and thus find themselves prisoners of a condition characterized by uncertainty at the medical, legal and ethical decision-making levels. In addition, these conditions, which can last indefinitely, also place great emotional and monetary strain on families, large burdens on care-takers - often leading to increased rates of burn-out - and large financial stress on medical structures and public finances due to the large costs imposed by prolonged intensive care. The present project is aimed at evaluating the potential of non-invasive Low Intensity Focused Ultrasound Pulsation (LIFUP) of thalamus (a key area for the consciousness network) as a neurorestorative stimulation for patients with severe brain injury. LIFUP will be performed during two sessions (one occurring after deep sedation is stopped and the second one occurring just before discharge). The proposed experiment will involve behavioral (i.e., CRS-R) and paramedical (i.e., MRI/fMRI) measurements just before and after each of the two LIFUP sessions (i.e., 5 non-consecutive minutes of stimulation in each session) in a small sample of patients (up to 15 acute and 15 chronic DOC patients) in order to evaluate the feasibility of a full scale clinical trial. The duration of participation in the study will be a year. In terms of impact, we think this project would have a number of immediate consequences. (i) A successful pilot study and any indication that this approach might have the hypothesized effect would place us in a unique position to initiate a fully-fledged double-blind clinical trial in a large cohort of patients. (ii) From a purely scientific point of view, by virtue of testing what is today the most prominent physiological hypothesis concerning loss and recovery of consciousness after severe brain injury, this project has a direct repercussion on our understanding of the mechanisms underlying these conditions. (iii) From a clinical and patient management point of view the present project is the first necessary step towards opening a completely new avenue for care-taking in patients suffering from this devastating condition for which there is no intervention. In particular, if this project were successful in the long run (e.g., after a double-blind full clinical trial), it could make widely available a non-invasive protocol which could substitute the currently highly invasive (and therefore not widely available, and high risk) only intervention available.