Our Doctors

Our Doctors

Dr. Joseph Neimat

Dr. Joseph Neimat, MD

The appointment of Joseph S. Neimat, M.D., was approved by the UofL Board of Trustees at its Jan. 14 meeting.

“In Joseph Neimat, the UofL School of Medicine is getting a chair with an excellent balance of expertise in research, clinical care and medical education,” Dean Toni M. Ganzel, M.D., said. “His knowledge and skills will greatly benefit our students, residents, patients and community.”

Neimat comes to UofL from Vanderbilt University in Nashville, Tenn., where he has held a variety of positions: associate professor and the director of human neurophysiological research, neurotrauma, epilepsy surgery and the functional neurosurgery fellowship in the Department of Neurosurgery; and a founding member of the Vanderbilt Initiative in Surgery and Engineering. He was medical director of inpatient neurosurgery and neurosurgery operating rooms at Vanderbilt, and served on the curriculum planning committee of Vanderbilt University Medical School.

He also was chief of neurosurgery for Tennessee Valley Health Care of the Veterans Administration and held joint appointments with Vanderbilt’s Center for Integrative & Cognitive Neuroscience, Psychiatric Neuroimaging Program and Department of Psychology.

Neimat’s current research interests include investigation of the affective and cognitive properties of the basal ganglia – structures located deep in the brain that are responsible for normal movement. His research also examines the clinical application of neural stimulation in the treatment of refractory medical disease, or disease that is resistant to current therapies. He has received funding from the National Institutes of Health as well as from industry to support his research.

He serves as an ad-hoc reviewer for the NIH Study Section on Clinical Neuroscience and Neurodegeneration. He also serves on the Boards of Directors of American Society for Stereotactic and Functional Neurosurgery and the World Society for Stereotactic and Functional Neurosurgery. He is the lead or co-author of approximately 90 peer-reviewed articles, published abstracts and textbook chapters.

Neimat earned a bachelor’s degree at Dartmouth, double majoring in music and biochemistry, and then earned a master’s in neurobiology and a medical degree from Duke University. He completed his residency at Massachusetts General Hospital in Boston and a fellowship in functional neurosurgery at the University of Toronto. He is board certified in neurological surgery.

Thomas J. Altstadt, MD, FAANS

Assistant Professor, Department of Neurosurgery


Curriculum Vitae

Indiana University School of Medicine, M.D.

Neurological Residency Training at Indiana University School of Medicine

Dr. Altstadt specializes in minimally invasive and complex spine surgery and the application of image-guided navigation to the treatment of spinal disorders. He also performs general and peripheral nerve neurosurgery.

Dr. Altstadt joined the University of Louisville Department of Neurosurgery in August, 2012. Prior to coming to UofL, he practiced neurosurgery from 2008-2012 in Oregon with Southern Oregon Neurosurgical & Spine Associates, PC. He is licensed in Kentucky, Indiana and Oregon.

As a junior in medical school, Dr. Altstadt was inducted into the Alpha Omega Alpha Honor Medical Society. He went on to complete his medical degree, general surgery internship, neurological surgery residency, and an additional postgraduate fellowship in complex spinal surgery at Indiana University School of Medicine in Indianapolis. Dr. Altstadt is the recipient of the American College of Surgeons Award and the Pittman Surgical Scholarship Award and is the author of numerous peer reviewed articles.

Maxwell Boakye, MD, MPH, MBA, FACS, FAANS

Associate Professor, Department of Neurosurgery
Ole A., Mabel Wise & Wilma Wise Nelson Endowed Chair
Chief of Spinal Neurosurgery

Curriculum Vitae

Rutgers University, B.S. Mathematics and Physics
Weill Cornell Medical College, M.D.
Neurosurgical Residency Training at SUNY-Upstate
Subspeciality training in complex spinal neurosurgery at Emory University
Training in spinal oncology at Memorial Sloan-Kettering Cancer Center

Dr. Boakye specializes in general and complex spinal neurosurgery, spinal radiosurgery and minimally invasive neurosurgery.

In January 2011, Dr. Boakye moved his outcomes research laboratory and spinal cord injury labs from Stanford University to the Center for Advanced Neurosurgery at the University of Louisville. He recently submitted 4 neurosurgical outcomes research grants and one KSCHIRT grant investigating longitudinal outcomes of morphological sequelae of traumatic brain injury. Accomplishments this year include 6 published peer-reviewed publications, 1 accepted peer-reviewed publication, completion of University of Louisville enrollment for use of Riluzole in acute spinal cord injury, development of neurotrauma registry at the University and establishment of human transcranial magnetic stimulation (TMS lab) at Frazier rehab institute. He has also helped to implement a protocol for diffusion tensor imaging, voxel based morphometry and resting state FMRI at the Department of Neuroradiology at the University of Louisville.

The overall goals of my lab is to understand the physiology and plasticity of the sensorimotor system in health and in patients with spinal cord and brain injury and to use that knowledge to develop new surrogate markers of recovery, new methods of injury prognostication and new therapies for spinal cord and brain injury. Research in this section uses noninvasive multimodal methodologies including functional magnetic resonance imaging (FMRI), diffusion tensor imaging (DTI), transcranial magnetic stimulation (TMS), electroencephalography (EEG), somatosensory evoked potentials (SEP), and peripheral nerve stimulation (PNS) technologies to gain a comprehensive understanding of the physiology and plasticity of the sensorimotor system in healthy patients and in patients with spinal cord and brain injury.

Mary Ellen Buning, PhD, OTR/L, ATP/SMS

Assistant Professor, Department of Neurosurgery

Curriculum Vitae

University of Florida, B.S., Occupational Therapy
Colorado State University, M.S., Occupational Therapy
University of Pittsburgh, Ph.D., Rehabilitation Science

Mary Ellen Buning, PhD, OTR/L, ATP/SMS, is an occupational therapist with 30 years as a specialist in assistive technology. She is an active leader within RESNA, the Rehabilitation Engineering and Assistive Technology Society of North America. She is credentialed by RESNA both as an Assistive Technology Practitioner (ATP) and a Seating and Mobility Specialist (SMS). She is a lifelong member of the American Occupational Therapy Association and a member of the American Occupational Therapy Foundation Board of Directors.

Dr. Buning completed her PhD in Rehabilitation Science in 2002 at the University of Pittsburgh under the mentorship of Douglas Hobson, PhD, PE. She has a strong interest in information technology and during her doctoral work developed WheelchairNet, a virtual community on wheelchair use for those seeking an active, empowered life. She investigated the use of WheelchairNet as a support for decision-making when consumers are acquiring new wheelchairs.

She currently treats patients in the U of Louisville Physicians Clinic utilizing professional skills in wheelchairs and specialized seating, home modification, and adaptations for computer and Wi-Fi technologies. Her work also supports the translational research and quality of life goals of the Frazier Spinal Cord Medicine Program.

 Susan Caldecott-Johnson, MD

Assistant Professor
Specialty: Pediatric Rehabilitation


Curriculum Vitae

Dr. Caldecott-Johnson attended undergraduate school at Ohio State University and medical school at the University of Cincinnati. She completed her Pediatric residency at the Cincinnati Children’s Hospital Medical Center and Physical Medicine & Rehabilitation at the University of Cincinnati. She is one of only a few physicians quadruple-board certified in Pediatrics, Neurodevelopmental Disabilities, PM&R and Pediatric Rehabilitation Medicine. Dr. Caldecott-Johnson has special interests in Cerebral Palsy, Spasticity treatment, baclofen pumps, Spinal Cord medicine and Spina Bifida.

 John Gormley, MD

Assistant Professor
Specialty: General Rehabilitation


Curriculum Vitae

Dr. Gormley is board certified by the American Board of Physical Medicine and Rehabilitation and is committed to providing his hospital and office patients compassionate personalized attention as well as providing the most innovative, advanced health care in the region. In addition to general rehabilitation, he specializes in neuromuscular diseases.

 Robert F. James, MD, FAANS

Associate Professor, Department of Neurosurgery
Chief, Vascular Neurosurgery

Curriculum Vitae

West Chester University, B.S., Chemistry and Biology
Tulane University School of Medicine, M.D.
Neurosurgical Residency Training at University of Maryland Medical Center? and R. Adams Cowley Shock Trauma Center
Interventional Neuroradiology Training at University of Maryland Medical Center
Cerebrovascular and Endovascular Neurosurgery Fellowship at Vanderbilt University Medical Center

Dr. James’ clinical interests include open and minimally-invasive brain aneurysm treatments, aneurysmal subarachnoid hemorrhage, arteriovenous malformations (AVM), arteriovenous fistulas, acute stroke, cavernous malformations, carotid artery stenosis treatments including carotid stenting and open carotid endarterectomy, carotid-cavernous fistula, peripheral nerve entrapment surgery, trigeminal neuralgia (tic douloureux) microvascular decompression, Adult Chiari syndrome, Moyamoya disease, traumatic brain injury, sports-related concussion, meningiomas, head and neck tumor embolization, and radiosurgery (Gamma Knife and Cyberknife).

Past Experience: Dr. James is board-certified as a diplomate of the American Board of Neurological Surgery and is a Senior Member of the Society of NeuroInterventional Surgery. Dr. James is a member of an elite group of neurosurgeons dual-trained in both open cranial neurovascular surgery and minimally-invasive endovascular neurosurgery. Dr. James served as faculty and Instructor of Clinical Neurosurgery with the Department of Neurological Surgery at Vanderbilt University School of Medicine. Dr. James then joined the faculty at the Brody School of Medicine at East Carolina University as an Assistant Professor of Neurosurgery and was successful in building the first joint cerebrovascular and endovascular neurosurgery program in eastern North Carolina serving a population of over 1.3 million people.

Current Position and Expertise: Dr. James was recruited to join the University of Louisville School of Medicine as Associate Professor of Neurosurgery and Chief of Vascular Neurosurgery. Dr. James is a nationally known and highly regarded expert in both open cerebrovascular and minimally-invasive endovascular neurosurgery. This dual-training allows Dr. James to offer an unbiased medical opinion in regards to which treatment option is best for his patients.

Dr. James has been invited to speak at numerous national neurosurgery and neuroendovascular meetings in his area of expertise and has published many scientific articles on cerebrovascular disease treatments. He is a committed educator having taught dozens of residents and fellows as faculty at national neuroendovascular practical courses. Dr. James gained recent recognition as the only neurosurgeon invited to write two chapters in the cerebrovascular section of Neurosurgery Knowledge Update, a new book planned for publication by the American Association of Neurological Surgeons (AANS).

Cerebrovascular and Stroke Research: Dr. James won the 2012 Robert Simon Chair of Research from the Brain Aneurysm Foundation and the East-West Collaboration Grant Award for his research evaluating heparin in aneurysmal subarachnoid hemorrhage. He has gained additional grant funding to lead a national, multi-center clinical trial based out of the University of Louisville that will evaluate low-dose heparin administration following cerebral aneurysm rupture. This study is designed to reduce neuroinflammation and prevent memory and cognitive deficits commonly seen in patients who survive a ruptured brain aneurysm. In addition, Dr. James will be bringing the HEAT aneurysm coiling trial to the University of Louisville that will compare gel coated coils to traditional coils in an attempt to understand which type of coil is better at fixing brain aneurysms. Dr. James will also be bringing a National Institutes of Health (NIH) funded clinical trial named MISTIE 3 to the University of Louisville that will evaluate new surgical treatments for hemorrhagic stroke, where current treatment options are very limited. Dr. James’ interest in clinical research stems from his commitment to find the safest and most effective methods to treat his patients who often have the most complex neurovascular problems. He would like to improve our understanding of these potentially devastating cerebrovascular disorders and to improve outcomes for all patients who suffer from them.

 Darryl L. Kaelin, MD

Chief, Associate Professor and Residency Director, Division of Physical Medicine and Rehabilitation
Specialty: Traumatic Brain Injury


Curriculum Vitae

Dr. Kaelin specializes in neurorehabilitation with a focus on traumatic brain injury and stroke. He is a nationally-renowned speaker on the subjects of concussion, spasticity management and neuropharmacology.

Darryl L. Kaelin, M.D. is a physician board certified by the American Board of Physical Medicine and Rehabilitation and American Board of Electrodiagnostic Medicine. He is the Division Chief of Physical Medicine and Rehabilitation and an Associate Professor in the Dept. of Neurological Surgery at the University of Louisville, where he directs the clinical inpatient rotation for the Division’s residents and serves as Residency Director.

Dr. Kaelin has published widely in peer-reviewed journals on brain injury medical education, pharmaceutical treatments, spasticity and service reimbursements. He has also led numerous, non-published medication trials sponsored through pharmaceutical funding. He has delivered presentations at regional and national conferences in the areas of spasticity management, pharmaceutical management of brain injury and medical business practice issues. He holds several positions within the Academy of Physical Medicine and Rehabilitation and the Association of Academic Physiatrists. He speaks nationally and internationally on several rehabilitation topics including the management of spasticity, deep vein thrombosis, and neuropharmacology.

Dr. Kaelin obtained his undergraduate degree from the University of Notre Dame where he played varsity baseball. He earned his medical degree from the University of Louisville School of Medicine and completed his specialty training at the Medical College of Virginia where he presided as their chief resident.

Prior to assuming his current positions with the University of Louisville and Frazier Rehabilitation Center, Dr. Kaelin spent six years as the Medical Director of the Acquired Brain Injury Program at Atlanta’s Shepherd Center, a catastrophic care hospital for people with spinal cord and brain injuries. While at the Shepherd Center, he also served as the Medical Director of Brain Injury Research and was a Clinical Associate Professor of Physical Medicine & Rehabilitation in Emory University’s School of Medicine.

Previously, Dr. Kaelin served for 10 years as the Medical Director of Brain Injury Rehabilitation at the Hook Institute in Indianapolis, where he managed patients with neurological trauma.

Dr. Kaelin is a native of Louisville, Kentucky, where he currently lives with his wife and their three children. Dr. Kaelin enjoys coaching sports and traveling in his leisure time.

Maria Koutourousiou, MD

Assistant Professor, Department of Neurosurgery
Director, Pituitary and Skull Base Program

Curriculum Vitae

Aristotle University of Thessaloniki, Greece, M.D.; Neurosurgical Residency Training at General Hospital of Athens “G. Gennimatas”, Greece; Minimal invasive and Endoscopic Neurosurgery Fellow at UMC St Radboud, Nijmegen, The Netherlands; Endoscopic and Open Skull Base Surgery Fellow at University of Pittsburgh Medical Center, Pittsburgh, PA.

Dr. Koutourousiou specializes in endoscopic endonasal approach (EEA) and open skull base surgery, pituitary tumors, skull base tumors, minimally invasive neurosurgery.

Dr. Koutourousiou received her M.D. from the Aristotle University of Thessaloniki, Greece and completed a neurosurgical residency at the General Hospital of Athens “G. Gennimatas”, Greece. She underwent subspecialty fellowship training in endoscopic pituitary surgery and minimal invasive neurosurgery at the UMC St Radboud, Nijmegen, The Netherlands. From 2010 to 2014, she spent four years at the Center of Cranial Base Surgery at the University of Pittsburgh Medical Center completing a research and clinical fellowship training in Endoscopic Endonasal Approaches and Open Skull Base Surgery for the treatment of brain and skull base tumors. Her research focused on evaluating patient outcome following skull base surgeries has been published and presented in numerous national and international neurosurgical meetings.

Dr. Koutourousiou’s work in Skull Base Surgery has been recognized and awarded by the European Skull Base Society (2009) and the World Federation of Skull Base Societies (2012)..



Haring J.W. Nauta, MD, PhD, FACS

Professor, Department of Neurosurgery
Neurosurgery Residency Program Director

Curriculum Vitae

Duke University, B.S., Biology and Chemistry; Case Western Reserve University School of Medicine, M.D.; Case Western Reserve University School of Medicine, Ph.D.; Neurosurgical Residency Training at University of Toronto

Dr. Nauta’s long and distinguished career began when he was a Guest Investigator at the Institut fur Hirnforschung der Universitat in Zurich, Switzerland. From there he became an Assistant Professor of Neurosurgery at the University of Toronto. Two years later, he joined the University of Texas Medical Branch at Galveston as an Associate Professor of Neurosurgery.

He then spent an eight year stint as an Associate Professor of Neurosurgery and Radiation Oncology at the prestigious Johns Hopkins University in Baltimore, Maryland. Afterwards, he returned to the University of Texas Medical Branch at Galveston, this time as a Professor of Neurosurgery. He later served as Chairman of their Neurosurgery department.

Dr. Nauta joined the University of Louisville in 2010. At UofL, he specializes in brain and spinal cord tumors, aneurysms and AVMs, lumbar stenosis, cervical disc disease, Chiari malformation, syringomyelia, adult hydrocephalus and special procedures for pain. He is also the Director of the department’s Residency Program.

 Megan B. Nelson, MD

Assistant Professor
Specialty: Cancer Rehabilitation


Curriculum Vitae

Dr. Nelson is a Physical Medicine and Rehabilitation specialist with fellowship training in Cancer Rehabilitation. Focusing on the unique functional needs of cancer patients, she works with oncologists and the comprehensive cancer team serving patients from initial diagnosis, throughout treatment and after treatment. She treats the whole patient, including musculoskeletal and neurological complaints, neuropathic pain, spasticity, lymphedema, fatigue and overall quality of life.


 John Shaw, MD

Assistant Professor
Specialty: Orthopedic Surgery/General Rehab


Curriculum Vitae

Dr. Shaw specializes in the treatment of spasticity with Botox, implant and management of Baclofen pumps, stroke rehab including tendon transfer, and restoring function in the tetraplegic hand. In addition to rehabilitation, Dr. Shaw is board certified in orthopedic surgery.


 Sarah Wagers, MD

Assistant Professor
Specialty: Traumatic Brain Injury


Curriculum Vitae

Dr. Wagers is a specialist in Physical Medicine and Rehabilitation. She completed her undergraduate degree, medical school and residency at the University of Louisville. She has a special interest in patients with acquired brain injury in both the civilian and veteran populations.

 Michael Weaver, DO

Assistant Professor
Specialty: Sports Medicine


Curriculum Vitae

Dr. Weaver is Fellowship trained with a CAQ in Sports Medicine and certified by the American Board of Physical Medicine and Rehabilitation. He has special interest in low back pain, myofascial pain, concussion, adaptive sports, ultrasound and electrodiagnostics. Dr. Weaver specializes in the treatment and management of musculoskeletal disorders.

Brian Williams, MD

Assistant Professor, Director of Brain Tumor Program

Dr. Brian Williams is an Assistant Professor in the Deprtment of Neurosurgery at the University of Louisville. He joined the faculty in August 2016 after completing his residency in neurological surgery and specialty training in neurosurgical oncology and skull base surgery. Dr. Williams has special expertise in treating primary and metastatic tumors of the brain, spine, and skull base. He has multiple awards recognizing his excellence in research including the Integra Foundation Award from the Congress of Neurological Surgeons and the Crutchfield Gage Award from the Neurosurgical Society of the Virginias. Dr. Williams's laboratory effort focuses on understanding the stem cell biology of glioblastoma tumor cells and the role of hypoxia signaling in peritumoral edema.

In addition to his sub-specialty, Dr. Williams performs general neurosurgery and spinal surgery including spinal deformity correction procedures and minimally invasive procedures. He is licensed in Kentucky and Texas.

William Williamson, MD

Assistant Professor
Specialty: Stroke - Sub Acute Rehab


Curriculum Vitae

Dr. Williamson specializes in stroke rehab and geriatrics. He directs the subacute and acute units in the Louisville metro area and is board certified in Physical Medicine and Rehabilitation.