The Stanford Moyamoya Team

Our Team

Gary K. Steinberg, MD, PhD

Bernard and Ronni Lacroute-William Randolph Hearst
Professor of Neurosurgery and the Neurosciences
Chairman, Department of Neurosurgery
Founder and Co-Director, Stanford Stroke Center


As founder and Co-Director of the Stanford Stroke Center, Dr. Steinberg has practiced medicine at Stanford for more than 29 years. He has pioneered stereotactic microsurgical techniques to repair intracranial vascular malformations and certain aneurysms that were previously considered untreatable. He has also refined revascularization techniques for patients with cerebrovascular occlusions, as well as moyamoya disease.

Dr. Steinberg is currently investigating an innovative approach to improve stroke recovery by transplanting stem cells into damaged brain tissue.


Michael Marks, MD
Professor of Radiology and (by courtesy) Neurosurgery
Director, Stanford Stroke Center Neuroradiology and Interventional Neuroradiology

As Director of Neuroradiology for the Stanford Stroke Center, Dr. Marks oversees the endovascular treatment program. Using catheter-based approaches, he has pioneered techniques to effectively cure cerebral aneurysms by inserting platinum coils and using special glues to obliterate arteriovenous malformations. Dr. Marks has also employed endovascular techniques to treat ischemic cerebrovascular disorders. He has broad experience with cerebral angioplasty and is currently developing a new laser therapy for vaporizing intracranial thrombi.


Robert Dodd, MD, PhD
Assistant Professor of Neurosurgery and Radiology

Dr. Dodd received his medical degree from the Stanford University School of Medicine, where he also earned a PhD in Neurosciences from the Department of Neurobiology and completed an endovascular fellowship. His research interests have been in cerebral blood vessel reactivity and stroke. Dr. Dodd's clinical interests include endovascular and microsurgical treatment of intracranial aneurysms and arteriovenous malformations; percutaneous and surgical interventions for both extracranial and intracranial carotid artery occlusive disease; and minimally invasive neurosurgery through the use of neuroendoscopy and keyhole approaches.


Huy Do, MD
Professor of Radiology and (by courtesy) Neurosurgery

Dr. Do employs interventional neuroradiologic approaches to treat both ischemic and hemorrhagic cerebrovascular disorders. He has developed expertise in cerebral angioplasty and intra-arterial thrombolysis, as well as the treatment of aneurysms, arteriovenous malformations and cerebral vasospasm.

Dr. Do's current research focuses on evaluation of neuroprotectants for ischemic strokes, development of novel laser microdevices for emulsification of intracranial clots, stenting of carotid and vertebral arterial stenoses, evaluation of new liquid embolic agents for arteriovenous malformations, neuroimaging of strokes, vascular malformations, aneurysms using advanced MRI techniques, and treatment of painful compression fractures with acrylic cement.


Jeremy J. Heit, MD, PhD
Clinical Assistant Professor of Radiology and, by courtesy, of Neurosurgery
Neurointerventional Radiologist, Stanford University Hospital
Diagnostic Neuroradiologist, Stanford University Hospital

Dr. Heit is a neurointerventional surgeon who performs minimally invasive, image-guided procedures in the brain, spine, and neck. The procedures include diagnostic cerebral angiography, endovascular stroke triage and therapy, cerebral aneurysm treatment, cerebral vasospasm treatment, cerebral angioplasty, dural arteriovenous fistula diagnosis and treatment, arteriovenous malformation treatment, carotid stent placement, vertebroplasty, spinal and intracranial tumor embolization, percutaneous sclerotherapy for the treatment of vascular malformations, and percutaneous biopsy using ultrasound, CT, and fluoroscopic guidance among other procedures. Dr. Heit is developing novel imaging techniques for the evaluation of patients with ischemic cerebrovascular disease, including stroke, vasospasm, and Moyamoya disease.


Penelope Zeifert, PhD
Chief, Neuropsychology Services
Co-Director, Stanford Center for Memory Disorders

Dr. Zeifert has been Director of the Stanford Neuropsychology Service for 15 years, and Co-Director of the Stanford Center for Memory Disorders for 10. She oversees the Moyamoya Neuropsychology Program, in which baseline cognitive-behavioral evaluations are provided to adult patients prior to surgery, and the results used to help guide ongoing treatment at neurosurgical follow-up. She and colleagues Peter Karzmark, PhD, Gary Steinberg, MD, PhD, Teresa Bell-Stephens, CNRN, and Les Dorfman, MD, have been collaborating in an ongoing research program to evaluate the neurocognitive changes of moyamoya disease before and after treatment.

Rabia Qaiser, MD
Clinical Instructor, Cerebrovascular Neurosurgery

Dr. Qaiser received her medical degree from Karachi Medical and Dental College and completed a year of house officership from Aga Khan University Karachi, both in Pakistan. She then completed her general surgery internship from Huron Hospital in Cleveland. Afterwards, she completed two years of pre-residency fellowship at Brigham and Women’s Hospital and Boston Children’s Hospital, and her neurosurgery residency at the University of Minnesota. Then, she completed a pediatric fellowship at Riley Children’s Hospital from Indiana University. After this, she joined West Virginia University faculty as a Pediatric Neurosurgeon and is currently pursuing a cerebrovascular fellowship at Stanford. Rabia is interested in pediatric cerebrovascular diseases, particularly Moyamoya disease, arteriovenous malformations, cavernomas and the occasional aneurysm.


Teresa Bell-Stephens, CNRN

Teresa has worked with the Department of Neurosurgeryt since 1990. She has extensive experience in critical care, and her current focus is on coordinating the cerebrovascular surgery program, with an emphasis on moyamoya disease, vascular malformations and intracranial aneurysms. Teresa is a frequent lecturer for Bay Area nurses on various neuroscience nursing topics and has presented many papers at the annual meetings of the American Association of Neuroscience Nurses (AANN) and the World Federation of Neuroscience Nurses (WFNN). She has published peer reviewed neuroscience nursing articles in various journals.

Joli Vavao, MSN, ACNP, CNRN

Joli joined the Neurosurgical team in 2004. She obtained her master's degree as an acute care nurse practitioner from the University of California, Los Angeles. She has worked as a nurse for over 20 years specializing in neurosurgery and stroke neurology. She has received national certification in neuroscience nursing. She plays an active role coordinating the care of cerebrovascular patients in both an inpatient and outpatient setting. She participates in lectures to hospital staff and local health care professionals regarding the care of neuroscience patients.  She also serves as lead APP in the department of neurosurgery.  

Mary L. Marcellus, RN

Originally from Connecticut, Mary came to Stanford in 1980. She began as a staff nurse in the ICU and then went on to become an Assistant Nurse Manager for several years before taking on the role of Interventional Neuroradiology Nurse Coordinator in 1993. She has lectured on various cerebrovascular topics as well as published several articles in her area of expertise. Patient advocacy remains the most important part of her daily patient care responsibilities.