Correlation between neurobehavioural assessment and functional magnetic resonance imaging in the diagnosis of prolonged disorders of consciousness.

The misdiagnosis rate of prolonged disorders of consciousness remains at approximately 40%, owing to overlap between diagnostic criteria and inconsistencies in patient responses. Improved accuracy is essential for the appropriate provision of treatment and rehabilitation. Neuroimaging may provide additional diagnostic information to standard neurobehavioural assessment, enabling identification of higher levels of awareness. In this study, the Sensory Tool to Assess Responsiveness (STAR) neurobehavioural assessment was used to assess the level of awareness of 19 patients with prolonged disorders of consciousness. Patients also completed an fMRI diagnostic assessment. The degree of concordance between fMRI and STAR diagnoses was substantial, despite significant delays for some patients between the two assessments. Discrepant diagnoses may relate to this delay or to the inconsistency of responses which characterise the minimally conscious state. The findings indicate that fMRI neuroimaging and STAR neurobehavioural assessment, while largely concordant, may identify different facets of awareness in some patients, which supports the use of both types of assessment in forming a diagnosis. Recommendations for future research include minimal delays between neurobehavioural and neuroimaging assessment, larger patient cohorts, and the use of multiple shorter fMRI assessments which provide more opportunities for patients to exhibit relevant behaviours.

Neurobehavioural assessment and diagnosis in disorders of consciousness: a preliminary study of the Sensory Tool to Assess Responsiveness (STAR).

The Sensory Tool to Assess Responsiveness (STAR) is an interdisciplinary neurobehavioural diagnostic tool for individuals with prolonged disorders of consciousness. It utilises current diagnostic criteria and is intended to improve upon the high misdiagnosis rate in this population. This study assesses the inter-rater reliability of the STAR and its diagnostic validity in comparison with the Coma Recovery Scale-Revised (CRS-R) and the Wessex Head Injury Matrix (WHIM). Participants were patients with severe acquired brain injury resulting in a disorder of consciousness, who were admitted to the Royal Leamington Spa Rehabilitation Hospital between 1999 and 2009. Patients underwent sensory stimulation sessions during their period of admission, which were recorded on video. Using this footage, patients were re-assessed for this study using the STAR, WHIM and CRS-R criteria. The STAR demonstrated "moderate" inter-rater reliability, "substantial" diagnostic agreement with the CRS-R, and "moderate" agreement with the WHIM. There were no significant differences between diagnoses assigned by the different assessments. The STAR demonstrated a good degree of inter-rater reliability in identification of diagnoses for patients with disorders of consciousness. The diagnostic outcomes of the STAR agreed at a good level with the CRS-R, moderately with the WHIM, and did not significantly differ from either. This demonstrates the reliability and validity of the STAR, showing its appropriateness for clinical use. Future longitudinal studies and research into the STAR's applicability in long-stay rehabilitation are indicated.