Michael I. Miller | |
---|---|
Born | 1955 (age 68–69) |
Nationality | American |
Alma mater | The State University of New York at Stony Brook Johns Hopkins University |
Known for | Computational anatomy [1] |
Spouse | Elizabeth Patton Miller [2] |
Children | 1 |
Awards | Presidential Young Investigator Award Johns Hopkins University Gilman Scholar [3] IEEE Elected Fellow [4] |
Scientific career | |
Fields | Biomedical Engineering Neuroscience Pattern Theory |
Institutions | Washington University in St. Louis Johns Hopkins University |
Thesis | Statistical Coding of Complex Speech Stimuli in the Auditory Nerve (1983) |
Doctoral advisor | Murray B. Sachs [5] |
Website |
Michael Ira Miller (born 1955) is an American-born biomedical engineer and data scientist, and the Bessie Darling Massey Professor and Director of the Johns Hopkins University Department of Biomedical Engineering. He worked with Ulf Grenander in the field of Computational Anatomy as it pertains to neuroscience, specializing in mapping the brain under various states of health and disease by applying data derived from medical imaging. Miller is the director of the Johns Hopkins Center for Imaging Science, Whiting School of Engineering and codirector of Johns Hopkins Kavli Neuroscience Discovery Institute. Miller is also a Johns Hopkins University Gilman Scholar. [6]
Miller received his Bachelor of Engineering from The State University of New York at Stony Brook in 1976, followed by a Master of Science degree in 1978 and PhD in biomedical engineering in 1983, both from the Johns Hopkins University. [7] [8]
He completed postdoctoral research on medical imaging at Washington University in St. Louis with Donald L. Snyder, then chair of the Electrical Engineering department. In 1985, he joined the faculty of Electrical Engineering at Washington University, where he was later named the Newton R. and Sarah Louisa Glasgow Wilson Professor in Engineering. [9] [10] During his early years at Washington University, Miller received the Presidential Young Investigator Award. [11] From 1994 to 2001, Miller was a visiting professor at Brown University's Division of Applied Mathematics, where he worked with Ulf Grenander on image analysis.
In 1998, Miller joined the Department of Biomedical Engineering at Johns Hopkins University as the director of the Center for Imaging Science. [12] He was later named the Herschel and Ruth Seder Professor of Biomedical Engineering, and was appointed by Johns Hopkins University President Ronald J. Daniels as one of 17 inaugural University Gilman Scholars in 2011. [6] [13] [14] In 2015, Miller became the co-director of the newly established Kavli Institute for Discovery Neuroscience. [15] In 2017, Miller was named the Massey Professor and Director of the Department of Biomedical Engineering at the Johns Hopkins University. [7] [16] In 2019, he was elected as a IEEE Fellow. [17]
Miller did his doctoral work on neural codes in the Auditory system under the direction of Murray B. Sachs and Eric D. Young in the Neural Encoding Laboratory [18] at Johns Hopkins University. With Sachs and Young, Miller focused on rate-timing population codes of complex features of speech including voice-pitch [19] and consonant-vowel syllables [20] encoded in the discharge patterns across the primary auditory nerve. These neural codes were one of the scientific works discussed as the strategy for neuroprosthesis design at the 1982 New York Academy of Science [21] meeting on the efficacy and timeliness of Cochlear implants.
Miller's work in the field of brain mapping via Medical imaging, specifically statistical methods for iterative image reconstruction, began in the mid 1980s when he joined Donald L. Snyder at Washington University to work on time-of-flight positron emission tomography (PET) systems being instrumented in Michel Ter-Pogossian's group. With Snyder, Miller worked to stabilize likelihood-estimators of radioactive tracer intensities via the method-of-sieves [22] . [23] This became one of the approaches for controlling noise artifacts in the Shepp-Vardi algorithm [24] in the context of low-count, time-of-flight emission tomography. It was during this period that Miller met Lawrence (Larry) Shepp, and he subsequently visited Shepp several times at Bell Labs to speak as part of the Henry Landau seminar series.
During the mid 1990s, Miller joined the Pattern Theory group at Brown University and worked with Ulf Grenander on problems in image analysis within the Bayesian framework of Markov random fields. They established the ergodic properties of jump-diffusion processes for inference in hybrid parameter spaces, which was presented by Miller at the Journal of the Royal Statistical Society as a discussed paper. [25] These were an early class of random sampling algorithms with ergodic properties proven to sample from distributions supported across discrete sample spaces and simultaneously over the continuum, likening it to the extremely popular Gibb's sampler of Geman and Geman. [26]
Grenander and Miller introduced Computational anatomy as a formal theory of human shape and form at a joint lecture in May 1997 at the 50th Anniversary of the Division of Applied Mathematics at Brown University, [27] and in a subsequent publication. [28] In the same year with Paul Dupuis, they established the necessary Sobolev smoothness conditions requiring vector fields to have strictly greater than 2.5 square-integrable, generalized derivatives (in the space of 3-dimensions) to ensure that smooth submanifold shapes are carried smoothly via integration of the flows. [29] The Computational anatomy framework via diffeomorphisms at the 1mm morphological scale is one of the de facto standards for cross-section analyses of populations. Codes now exist for diffeomorphic template or atlas mapping, including ANTS, [30] DARTEL, [31] DEMONS, [32] LDDMM, [33] StationaryLDDMM, [34] all actively used codes for constructing correspondences between coordinate systems based on sparse features and dense images.
David Mumford appreciated the smoothness results on existence of flows, and encouraged collaboration between Miller and the École normale supérieure de Cachan group that had been working independently. In 1998, Mumford organized a Trimestre on "Questions Mathématiques en Traitement du Signal et de l'Image" at the Institute Henri Poincaré; from this emerged the ongoing collaboration on shape between Miller, Alain Trouve and Laurent Younes. [35] They published three significant papers together over the subsequent 15 years; the equations for geodesics generalizing the Euler equation on fluids supporting localized scale or compressibility appeared in 2002, [36] the conservation of momentum law for shape momentum appeared in 2006, [37] and the summary of Hamiltonian formalism appeared in 2015. [38]
Miller and John Csernansky developed a long-term research effort on neuroanatomical phenotyping of Alzheimer's disease, Schizophrenia and mood disorder. In 2005, they published with John Morris an early work on predicting conversion to Alzheimer's disease based on clinically available MRI measurements using diffeomorphometry technologies. [39] This was one of the papers that contributed to a deeper understanding of the disorder in its earlier stages and the recommendations of the working group to revise the diagnostic criteria for Alzheimer’s disease dementia for the first time in 27 years. [40]
In 2009, the Johns Hopkins University BIOCARD [41] project was initiated, led by Marilyn Albert, to study preclinical Alzheimer's disease. In 2014, Miller and Younes demonstrated that the original Braak staging of the earliest change associated to the entorhinal cortex in the medial temporal lobe could be demonstrated via diffeomorphometry methods in the population of clinical MRIs, [42] and subsequently that this could be measured via MRI in clinical populations upwards of 10 years before clinical symptoms appeared. [43]
Positron emission tomography (PET) is a functional imaging technique that uses radioactive substances known as radiotracers to visualize and measure changes in metabolic processes, and in other physiological activities including blood flow, regional chemical composition, and absorption. Different tracers are used for various imaging purposes, depending on the target process within the body.
Iterative reconstruction refers to iterative algorithms used to reconstruct 2D and 3D images in certain imaging techniques. For example, in computed tomography an image must be reconstructed from projections of an object. Here, iterative reconstruction techniques are usually a better, but computationally more expensive alternative to the common filtered back projection (FBP) method, which directly calculates the image in a single reconstruction step. In recent research works, scientists have shown that extremely fast computations and massive parallelism is possible for iterative reconstruction, which makes iterative reconstruction practical for commercialization.
Morphometrics or morphometry refers to the quantitative analysis of form, a concept that encompasses size and shape. Morphometric analyses are commonly performed on organisms, and are useful in analyzing their fossil record, the impact of mutations on shape, developmental changes in form, covariances between ecological factors and shape, as well for estimating quantitative-genetic parameters of shape. Morphometrics can be used to quantify a trait of evolutionary significance, and by detecting changes in the shape, deduce something of their ontogeny, function or evolutionary relationships. A major objective of morphometrics is to statistically test hypotheses about the factors that affect shape.
Pattern theory, formulated by Ulf Grenander, is a mathematical formalism to describe knowledge of the world as patterns. It differs from other approaches to artificial intelligence in that it does not begin by prescribing algorithms and machinery to recognize and classify patterns; rather, it prescribes a vocabulary to articulate and recast the pattern concepts in precise language. Broad in its mathematical coverage, Pattern Theory spans algebra and statistics, as well as local topological and global entropic properties.
In neuroimaging, spatial normalization is an image processing step, more specifically an image registration method. Human brains differ in size and shape, and one goal of spatial normalization is to deform human brain scans so one location in one subject's brain scan corresponds to the same location in another subject's brain scan.
Statistical shape analysis is an analysis of the geometrical properties of some given set of shapes by statistical methods. For instance, it could be used to quantify differences between male and female gorilla skull shapes, normal and pathological bone shapes, leaf outlines with and without herbivory by insects, etc. Important aspects of shape analysis are to obtain a measure of distance between shapes, to estimate mean shapes from samples, to estimate shape variability within samples, to perform clustering and to test for differences between shapes. One of the main methods used is principal component analysis (PCA). Statistical shape analysis has applications in various fields, including medical imaging, computer vision, computational anatomy, sensor measurement, and geographical profiling.
In statistics, sieve estimators are a class of non-parametric estimators which use progressively more complex models to estimate an unknown high-dimensional function as more data becomes available, with the aim of asymptotically reducing error towards zero as the amount of data increases. This method is generally attributed to Ulf Grenander.
Donald Jay Geman is an American applied mathematician and a leading researcher in the field of machine learning and pattern recognition. He and his brother, Stuart Geman, are very well known for proposing the Gibbs sampler and for the first proof of the convergence of the simulated annealing algorithm, in an article that became a highly cited reference in engineering. He is a professor at the Johns Hopkins University and simultaneously a visiting professor at École Normale Supérieure de Cachan.
Brain morphometry is a subfield of both morphometry and the brain sciences, concerned with the measurement of brain structures and changes thereof during development, aging, learning, disease and evolution. Since autopsy-like dissection is generally impossible on living brains, brain morphometry starts with noninvasive neuroimaging data, typically obtained from magnetic resonance imaging (MRI). These data are born digital, which allows researchers to analyze the brain images further by using advanced mathematical and statistical methods such as shape quantification or multivariate analysis. This allows researchers to quantify anatomical features of the brain in terms of shape, mass, volume, and to derive more specific information, such as the encephalization quotient, grey matter density and white matter connectivity, gyrification, cortical thickness, or the amount of cerebrospinal fluid. These variables can then be mapped within the brain volume or on the brain surface, providing a convenient way to assess their pattern and extent over time, across individuals or even between different biological species. The field is rapidly evolving along with neuroimaging techniques—which deliver the underlying data—but also develops in part independently from them, as part of the emerging field of neuroinformatics, which is concerned with developing and adapting algorithms to analyze those data.
Marcus E. Raichle is an American neurologist at the Washington University School of Medicine in Saint Louis, Missouri. He is a professor in the Department of Radiology with joint appointments in Neurology, Neurobiology and Biomedical Engineering. His research over the past 40 years has focused on the nature of functional brain imaging signals arising from PET and fMRI and the application of these techniques to the study of the human brain in health and disease. He received the Kavli Prize in Neuroscience “for the discovery of specialized brain networks for memory and cognition", together with Brenda Milner and John O’Keefe in 2014.
Medical image computing (MIC) is an interdisciplinary field at the intersection of computer science, information engineering, electrical engineering, physics, mathematics and medicine. This field develops computational and mathematical methods for solving problems pertaining to medical images and their use for biomedical research and clinical care.
Computational anatomy is an interdisciplinary field of biology focused on quantitative investigation and modelling of anatomical shapes variability. It involves the development and application of mathematical, statistical and data-analytical methods for modelling and simulation of biological structures.
Group actions are central to Riemannian geometry and defining orbits. The orbits of computational anatomy consist of anatomical shapes and medical images; the anatomical shapes are submanifolds of differential geometry consisting of points, curves, surfaces and subvolumes,. This generalized the ideas of the more familiar orbits of linear algebra which are linear vector spaces. Medical images are scalar and tensor images from medical imaging. The group actions are used to define models of human shape which accommodate variation. These orbits are deformable templates as originally formulated more abstractly in pattern theory.
Statistical shape analysis and statistical shape theory in computational anatomy (CA) is performed relative to templates, therefore it is a local theory of statistics on shape. Template estimation in computational anatomy from populations of observations is a fundamental operation ubiquitous to the discipline. Several methods for template estimation based on Bayesian probability and statistics in the random orbit model of CA have emerged for submanifolds and dense image volumes.
Computational anatomy (CA) is the study of shape and form in medical imaging. The study of deformable shapes in CA rely on high-dimensional diffeomorphism groups which generate orbits of the form . In CA, this orbit is in general considered a smooth Riemannian manifold since at every point of the manifold there is an inner product inducing the norm on the tangent space that varies smoothly from point to point in the manifold of shapes . This is generated by viewing the group of diffeomorphisms as a Riemannian manifold with , associated to the tangent space at . This induces the norm and metric on the orbit under the action from the group of diffeomorphisms.
Large deformation diffeomorphic metric mapping (LDDMM) is a specific suite of algorithms used for diffeomorphic mapping and manipulating dense imagery based on diffeomorphic metric mapping within the academic discipline of computational anatomy, to be distinguished from its precursor based on diffeomorphic mapping. The distinction between the two is that diffeomorphic metric maps satisfy the property that the length associated to their flow away from the identity induces a metric on the group of diffeomorphisms, which in turn induces a metric on the orbit of shapes and forms within the field of Computational Anatomy. The study of shapes and forms with the metric of diffeomorphic metric mapping is called diffeomorphometry.
The Johns Hopkins University Department of Biomedical Engineering has both undergraduate and graduate biomedical engineering programs located at the Johns Hopkins University in Baltimore, Maryland.
Wojciech (Wojtek) Zbijewski is an American biomedical engineering and medical physics working in the fields of Computed tomography (CT), Cone beam computed tomography (CBCT), image reconstruction in CT, and applications of CT and CBCT in orthopedics. He is faculty at the Department of Biomedical Engineering at Johns Hopkins School of Medicine.
Diffeomorphometry is the metric study of imagery, shape and form in the discipline of computational anatomy (CA) in medical imaging. The study of images in computational anatomy rely on high-dimensional diffeomorphism groups which generate orbits of the form , in which images can be dense scalar magnetic resonance or computed axial tomography images. For deformable shapes these are the collection of manifolds , points, curves and surfaces. The diffeomorphisms move the images and shapes through the orbit according to which are defined as the group actions of computational anatomy.
Rajat Mittal is a computational fluid dynamicist and a professor of mechanical engineering in the Whiting School of Engineering at Johns Hopkins University. He holds a secondary appointment in the Johns Hopkins University School of Medicine. He is known for his work on immersed boundary methods (IBMs) and applications of these methods to the study of fluid flow problems.