Investigating ioflupane I¹²³ injection and single photon emission tomography as an imaging biomarker for long-term sequelae following mild traumatic brain injury

ABSTRACT

Objective: To determine whether there were differences in clinical outcomes for ioflupane I¹²³ injection (DaTscan) and single photon emission tomography consistent with early Parkinson’s disease (PD) among individuals with a history of mild traumatic brain injury (mTBI).

Methods: We performed a case-control study among patients presenting to the Emergency Room (ER) during 2006–2013 with mTBI (cases, n = 34) or without mTBI (controls, n = 33). We performed clinical and imaging measurements in cases and controls at least 1-year post-presentation to the ER (average three years four months).

Results: All DaTscans obtained were qualitatively normal. There were no qualitative DaTscan differences between cases and controls. There was, however, a significant increase in caudate asymmetry in controls versus cases (p = 0.02), but this finding was no longer significant after correction for multiple comparisons. There was a suggestion of a trend of poorer clinical score test measures among those with mTBI, although the overall mean score difference between cases and controls was not clinically significant.

Conclusion: Our small study does not provide support for DaTscan changes suggestive of PD in the one to seven years following mTBI. A trend towards poorer clinical measures was seen but was not clinically relevant in our small sample. Further work in a large population is necessary to support these findings.

KEYWORDS:

• Clinical trial
• case-control study
• observational study
• parkinson’s disease
• parkinsonism
• SPECT
• brain trauma

Acknowledgments

The authors thank Vimal Patel, PhD, medical and scientific writer at NorthShore Neurological Institute, for his assistance with copy editing, figure preparation, formatting, and submitting the manuscript for publication.

Disclosure statement

The authors report no conflicts of interest. The study was funded by an investigator-initiated grant awarded to Demetrius M. Maraganore, MD by GE Healthcare.