The drug relaxes spasticity that can result from brain injury and may be used to facilitate care, but is not normally used to restore function. The patients, a 24-year-old man and a 29-year-old man, had been in minimally conscious states for three years and 18 months, respectively. Their scores on a revised coma recovery scale (with a maximum of 23) increased from 10 -- 19 and 11 -- 22, respectively.

Minimally conscious state is defined as a consciousness disorder in which a patient shows fluctuating, but not reproducible, signs of self-awareness and the surroundings. Most patients in a minimally conscious state also have moderate to severe spasticity as a result of their injuries.

Dr. Konstantinos Margetis, who contributed significantly to this study, notes that some sporadic case reports have suggested a potential beneficial effect of ITB in recovery from disorders of consciousness. He and colleagues decided to search for the effect in a systematic way. ITB was indicated in this study, he said, and in the previous case series, to reduce spasticity since it facilitates care and probably minimizes some spasticity complications.

"The improvement in the level of consciousness was a very pleasant observation for us," he said. "It might have been due to an additional beneficial effect of receiving intrathecal baclofen in this group of patients." All six patients improved spasticity scores with treatment, and the two who also made gains in recovering consciousness apparently retained some ability, despite their brain injury, to sustain an awake, alert, and oriented state that might have been enhanced by the treatment. He hypothesizes the mechanism of this observed effect could be associated with the action of baclofen on receptors in the orexin system, which plays a role in maintaining wakefulness, and in the thalamic reticular nucleus, a brain structure associated with consciousness.

Next he would like to see a larger, multi-center study evaluate such factors as brain and nervous system activity observed in functional and neural pathway imaging (fMRI and DTI MRI respectively); analysis of changes in neurotransmitters in the cerebrospinal fluid; and tracking electrical activity in neural networks or response to a stimulus (EEG and evoked potential recordings).

"A complete research protocol designed with input from other disciplines will attempt to investigate every facet of this complex subject," he remarked. "A study like that will allow for definite conclusions about the role of intrathecal baclofen in the recovery of the disorders of consciousness. While we feel that the current results might lower the threshold for intrathecal baclofen treatment in spasticity patients with disorders of consciousness, should a multi-center a study establish a definite role for intrathecal baclofen in disorders of consciousness, then the potential will be very promising indeed."