Johns Hopkins Biomedical Engineering faculty
Tilak Ratnanather, DPhil
Associate Research Professor
Office: Clark 308B
Lab: Mathematical Analysis of NeuroImaging of the Cerebral Brain
B.Sc., Mathematics, University College London, 1985
D.Phil., Mathematical Sciences, University of Oxford, 1989
My research focus is on the analysis of brain structures which include hippocampus, cingulate gyrus, planum temporale, superior temporal gyrus, and the auditory and prefrontal cortexes. These structures are implicated in neuropsychiatric and neurodevelopmental disorders such as schizophrenia, Alzheimer's, epilepsy, major depression, speech and language processing.
Other interests include the physiological fluid mechanics of the cochlear outer hair cell, the study of nonlinear partial differential equations (e.g. EPDiff in Computational Anatomy, Webster's Equation in bioacoustics, boundary layer separation in physiological flows), and continuing education via online web courses in applied mathematics.
Examples of Research Questions
- How different is the shape of the hippocampus in the adolescent female with a risk for depression?
- How can schizophrenia affect thinning in the planum temporale?
- How is it possible for a profoundly deaf child to play music to a high level?
- How can demyelination affect connectivity between structures in the brain?
- How can stress affect the cochlear outer hair cell wall and thus the cochlea?
- is it possible to examine how the deafened brain functions with hearing aids?
- How do we limit the number of CT scans a child undergoes?
- Can MR scans be used to predict outcomes in cochlear implantation?
- Which part of the left ventricle is affected in sudden cardiac death?
- Can we quantify the effect of stroke on speech and language?
Li X, Samei E, Williams CH, Segars WP, Tward DJ, Miller MI, Ratnanather JT, Paulson EK, Frush DP. Effects of protocol and obesity on dose conversion factors in adult body CT. Med Phys. 2012 Nov;39(11):6550-71. doi: 10.1118/1.4754584.
Selemon LD, Ceritoglu C, Ratnanather JT, Wang L, Harms MP, Alridge K, Begovic A, Csernansky JG, Miller MI, Rakic, P. Distinct abnormalities of the primate prefrontal cortex caused by ionizing radiation in early or mid gestation. J. Comp. Neurol., 2013.
Priebe CE, Miller MI, Ratnanather JT. Segmenting Magnetic Resonance Images via Hierarchical Mixture Modelling. Computational Statistics and Data Analysis. Computational Statistics & Data Analysis, 50, 551–567. 2006.
Ceyhan E, Hosakere M, Nishino T, Alexopolous J, Todd RD, Miller MI, Botteron KN, Ratnanather JT. Statistical Analysis of Cortical Thickness Using Pooled Distances from Labeled Cortical Distance Maps. J. Math. Image Vision. 2011. 40:20-35.
Younes L, Ratnanather JT, Albin R, Aylward E, Nopoulos P, Pierson R, Johnson H, Magnotta V, Paulsen J, Margolis R, Miller MI, Ross CA. Regionally selective atrophy of subcortical structures in prodromal HD as revealed by statistical shape analysis. Human Brain Mapping. 2013.
Li X, Samei E, Williams CH, Segars WP, Tward DJ, Miller MI, Ratnanather JT, Paulsen EK, Frush DP. Effects of protocol and obesity on dose conversion factors in adult body CT. Medical Physics. 2012. 39:6550-6571.
Steinert-Threlkeld S, Ardekani S, Mejino JV, Detwiler LT, Brinkley JF, Halle M, Kikinis R, Winslow RL, Miller MI, Ratnanather JT. Ontological Labels for Automated Location of Anatomical Shape Differences. J. Biomedical Informatics. 2012. 45:522-557.