Commentary: Applications of functional neuroimaging to civil litigation of mild traumatic brain injury.

The current definition of mild traumatic brain injury (MTBI) is in flux. Presently, there are at least three working definitions of this disorder in the United States, with no clear consensus. Functional neuroimaging, such as single photon emission computed tomography (SPECT) and positron emission tomography (PET), initially showed promise in their ability to improve the diagnostic credibility of MTBI. Over the past decade, that promise has not been fulfilled and there is a paucity of quality studies or standards for the application of functional neuroimaging to traumatic brain injury, particularly in litigation. The legal profession is ahead of the science in this matter. The emergence of neurolaw is driving a growing use of functional neuroimaging, as a sole imaging modality, used by lawyers in an attempt to prove MTBI at trial. The medical literature on functional neuroimaging and its applications to MTBI is weak scientifically, sparse in quality publications, lacking in well-designed controlled studies, and currently does not meet the complete standards of Daubert v. Merrell Dow Pharmaceuticals, Inc., for introduction of scientific evidence at trial. At the present time, there is a clear lack of clinical correlation between functional neuroimaging of MTBI and behavioral, neuropsychological, or structural neuroimaging deficits. The use of SPECT or PET, without concurrent clinical correlation with structural neuroimaging (CT or MRI), is not recommended to be offered as evidence of MTBI in litigation.