Diffusion Tensor Imaging Features in a Rat Model of Adult Chronic Communicating HydrocephalusName : Dr. Gabriel D. Pinilla
Affliation : Department Of Neurosurgery
University : Johns Hopkins Hospital
Country : Baltimore, USA
Background: Diffusion Tensor Imaging (DTI) has been useful to characterize microstructural alterations of the brain parenchyma. In this study, we aimed to observe the Fractional Anisotropy (FA) and Mean Diffusivity (MD) in the white matter tracks of an animal model of chronic hydrocephalus.
Materials and Methods: Communicating chronic hydrocephalus was induced in five Sprague-Dawley adult rats, weighting 250g, by a bilateral kaolin injection into the subarachnoid space over the convexities. Five additional rats were used as controls. DTI data acquisition was obtained with a Bruker 11.7-T scan. Regional FA and MD were measured at Corpus Callosum (CC) and Cortico-Spinal Tracts (CST) at days 14, 60, 90, and 120 after injection. Statistical analysis was performed using Mann-Withney’s, Spearman and Friedman’s tests.
Results: Progressive ventricular enlargement was demonstrated in the injected group at all four time points (p<0.050). MD at the corpus-callosum (CC-MD) was significantly higher in rats with hydrocephalus: 14 (p=0.027), 60 (p=0.014), 90 (p=0.009), and 120 days (p=0.013). CC-MD showed a positive correlation with the ventricular volume (p<0.050), as well as a significant progressive increase in value over time (p=0.007). CC-FA was decreased in the hydrocephalic rats only at 90 days (p=0.021). There were no significant differences in CST-FA at any time point between the groups.
Conclusion: This study shows the feasibility of DTI analysis in a model of chronic communicating hydrocephalus over a prolonged period of time. Significant differences between groups, especially in CC-MD at the studied time points, should be further investigated and correlated with symptoms in larger populations.
Biography: Gabriel Pinilla, M.D. is currently pursuing a Post-Doctoral Fellowship in Cerebrospinal Fluid Disorders at the Johns Hopkins Department of Neurosurgery. He graduated Cum Laude from the Industrial University of Santander School of Medicine, where he obtained an additional A.Sc. degree in Pharmacy Technology. He is a Pg.Cert. student in the Epidemiology program and his main research interests are translational models of neurological diseases and the statistical assessment of data below the limit of detection in the context of biomarkers concentration studies.