Neurosurgery Clinical Instructors

Kumar Abhinav, BSc. (Hons.), MBBS, FRCS (Neurosurgery)
Skull Base Neurosurgery

Dr Abhinav obtained his medical degree from the Guy's, King's and St Thomas' School of Medicine, King's College London, University of London.  During his medical training he also obtained an additional Bachelor of Science degree in Radiological Sciences. He undertook his neurosurgical training in Bristol and Plymouth and completed it in July 2017.  He was awarded the Fellowship of the Royal College of Surgeons of England in Neurosurgery in 2016.

He also undertook an enfolded two year research fellowship towards the award of doctor of medicine as a postdoctoral associate in the Department of Neurosurgery, University of Pittsburgh Medical Centre. This period under the mentorship of Drs. Juan C Fernandez-Miranda and Robert Friedlander was funded by the prestigious Ellison-Cliffe Travelling fellowship award from the Royal Society of Medicine, London and the University of Pittsburgh Brain Institute. During this placement in the surgical neuroanatomy and imaging laboratory, he built up expertise in detailed neurosurgical anatomy particularly those pertaining to the complex skull base regions. This work led to descriptions of surgically relevant endoscopic skull base anatomy. He also extensively investigated the use of advanced white matter imaging techniques in examining the structural connections in the normal brain and in pathological condition.

His research work has led to multiple peer reviewed publications and presentations at scientific meetings. He has also contributed book chapters on skull base anatomy and recently co-edited the Neurosurgery section of the Gray's Applied Surgical Anatomy (Elsevier) textbook, a major international project.

Over the last academic year, Dr Abhinav completed clinical cerebrovascular fellowship as a clinical instructor under the mentorship of Dr Gary K Steinberg and in particular, gained significant operative exposure to cerebral revascularization procedures.  He also undertook multiple clinical and basic science projects including a current ongoing effort directed at the evaluation of CSF biomarkers in Moyamoya disease. During this period, he was also instrumental in the setting up and launching of the Stanford Neuroanatomy Laboratory aimed at the education of residents and fellows and development of a dissection curriculum.

During the current academic year, he will be working under the mentorship of Dr Juan C Fernandez-Miranda to obtain surgical exposure to the advanced endoscopic skull base approaches and techniques and open surgical approaches to the posterolateral skull base. He will also be directing his effort into further development of the skull base laboratory to incorporate endoscopic work. Upon completion of his subspecialist fellowships he intends to pursue a clinical academic career in cerebrovascular and skull base neurosurgery.

Mark G. Bigder, BA, HBK, MD, MPH
Cerebrovascular Surgery

Dr Bigder was born and raised in Thunder Bay, Canada where he completed Bachelor of Arts in Psychology and Honours Bachelor of Kinesiology degrees through Lakehead University. He subsequently completed medical school and neurosurgical residency in Winnipeg at the University of Manitoba. During his residency, Dr Bigder completed a Master of Public Health degree in epidemiology at Harvard TH Chan School of Public Health. He has published research articles on Gamma Knife radiosurgery, microvascular decompression and various public health topics, and has presented his work at international conferences including the International Stereotactic Radiosurgery Society Congress, Congress of Neurological Surgeons and European Public Health Conference among others.

Dr Bigder has been involved in several leadership roles including serving as the Canadian Neurosurgical Society National Resident Representative, member of the Canadian Neurological Sciences Federation Scientific Planning Committee and member of the Canadian Neurosurgical Research Collaborative.

Dr Bigder, along with his wife Sara, together enjoy running, hiking and spending time in the outdoors with their daughter and two dogs. His love for travel and adventure has taken him on journeys to a number of destinations worldwide including the summits of Mt Batur, Cotopaxi, Kilimanjaro and Kala Patthar.

Daniel R. Kramer
Functional Neurosurgery

Daniel R. Kramer grew up in Oak Park, IL before completing his undergraduate degree at Northwestern University in cognitive science and philosophy.  He then completed his medical degree at the University of Pennsylvania and his neurosurgical training at the University of Southern California.

Dr. Kramer has a clinical interest in surgical treatments for movement disorders, epilepsy, and pain.  His research interests are focused on the interpretation of neural signals and the communication between brain areas, particularly to produce movement and somatosensation.  He works primarily on brain computer interface, where the human brain interfaces directly with machines to restore motor and sensory function to paralyzed individuals.

In his free time, he enjoys ultra-running, concerts, and snowboarding.

Yiping Li

Dr. Li grew up in the Midwest where he obtained an undergraduate degree from the school of pharmacy at Purdue University and obtained his medical degree from Indiana University.  He then completed a neurosurgery residency at the University of Wisconsin where he also completed his neuroendovascular fellowship in 2017.

As clinical instructor at Stanford, Dr. Li is currently concentrating on the treatment of complex cerebrovascular diseases including ischemia, cerebral aneurysms, arteriovenous and cavernous malformations. During his time off, Dr. Li enjoys spending time outdoors hiking and camping with his wife and daughter.

Mauricio Mandel, MD, PhD
Cerebrovascular Surgery

Dr. Mandel obtained his medical degree from the University of São Paulo Medical School, Brazil. He received the “Prof. Dr. Edmundo Vasconcelos Award” as the best student on all surgical disciplines upon completion of medical school. He subsequently completed his neurosurgical residency at the Hospital das Clinicas of University of Sao Paulo Medical School, Brazil.

After his residency, Dr. Mauricio started a busy private practice at Hospital Israelita Albert Einstein, Sao Paulo, Brazil.

His clinical and research interests are focused on minimally invasive neurosurgery. Dr. Mauricio attended a Ph.D. program at the University of Sao Paulo, Brazil, where he discussed a doctoral thesis entitled “Employment of minimally invasive neurosurgical techniques for treatment of unruptured brain aneurysms of the anterior circulation.”  During his Ph.D. thesis, he described an innovative minimally invasive approach for the treatment of middle cerebral artery aneurysms (transpalpebral “eyelid” approach). He has published several peer-reviewed articles and has presented his work at different international conferences.

As Clinical Instructor at Stanford, Dr. Mauricio is currently concentrating on gaining operative exposure to cerebral revascularization procedures with Dr. Gary Steinberg.

Dr. Mandel, along with his wife Suzana, enjoys running, hiking and traveling. He also enjoys playing the cello. He has been a cellist in several university symphony orchestras in Sao Paulo.

Ahmed Mohyeldin, MD, PhD
Skull Base
Endoscopic Skull Base
Neurosurgical Oncology

Dr. Mohyeldin completed his undergraduate education at Emory University with a degree in neuroscience and behavioral biology.  Having been selected as an All-American Athlete, he was drafted to play professional soccer in Atlanta prior to medical school. Dr. Mohyeldin completed his medical education at George Washington University. During medical school he was awarded a grant from the American Association of Neurological Surgeons and from the Maryland Stem Cell Research Fund to pursue a post-doctoral research fellowship at Johns Hopkins University under the mentorship of Dr. Alfredo Quinones-Hinojosa. His research investigated developmental transcriptional programs coopted by brain cancer with a specific focus on chordomas and glioblastomas. During this time, he developed the first animal model for chordoma and identified the transcription factor brachyury as a novel therapeutic target, which is currently the focus of a major NIH clinical trial as well as multiple drug design studies for chordoma patients. Dr. Mohyeldin pursued his neurosurgical training at Ohio State University, during that time he was awarded the R25 grant from NIH to further pursue this work. After completing his residency, he remained at OSU and pursued a clinical fellowship with Dr. Daniel Prevedello and Ricardo Carrau in advanced skull base and endoscopic cranial surgery. He comes to the Neurosurgery Department to work with Dr. Juan Fernandez-Miranda and collaborate with leading basic scientists at Stanford to identify and target important transcriptional programs that maintain cancer stem cell populations in chordoma to find a meaningful cure for this disease.

Margaret Pain
Pediatric Neurosurgery

Priv.-Doz. Dr. Martin N. Stienen (MD, FMH, FEBNS)

Dr. Stienen obtained his medical degree at the Ruhr-University Bochum (Germany), where he also earned his doctoral degree (MD) with highest honors (Summa Cum Laude) for experimental studies dealing with the conductivity of potassium channels of glial cells. He undertook his neurosurgical training at the Cantonal Hospital St.Gallen, and at the University Hospitals of Geneva and Zürich (Switzerland). Dr. Stienen has obtained the Swiss board certification for Neurosurgery (FMH) in 01/2018, and was nominated “Fellow of the European Board of Neurological Surgeons” (FEBNS) in 03/2018. He has been appointed consultant neurosurgeon at the University Hospital Zürich in 01/2018 and has achieved the rank of a private docent (venia legendi) at the University of Zürich with a habilitation thesis on “The Assessment of Complications and Outcomes in Modern Neurosurgical Patient Care”.

Dr. Stienen’s primary interest is caring for patients, and he is constantly motivated to bring out the best by seeing them recover well and getting back to their daily lives. Besides the clinical work, he has long-standing interest in research, focusing mainly on the three topics 1) Subjective and objective outcome assessment of patients with diseases of the spine, 2) Multi-dimensional assessment of patients after aneurysmal subarachnoid hemorrhage and 3) Training and education in Neurosurgery. Dr. Stienen has conducted studies and led research groups. He has published extensively in those fields, and is frequently invited as reviewer for international highly ranked academic journals.

As Clinical Instructor at Stanford, Dr. Stienen is currently concentrating on the treatment of complex diseases of the spine (Complex Spine Fellowship). After this, he will travel to South Korea for an additional spine fellowship, having been awarded with a travel grant from the Swiss Society of Neurosurgery. He will then continue to pursue a clinical academic career in neurosurgery as attending neurosurgeon at the University Hospital Zürich.

Rahul Singh

Dr. Singh recently completed his neurological surgery residency at West Virginia University. He completed his Bachelors of Science in biochemistry and Medical Degree from Rutgers University.  He enjoys being outdoors and reading fiction.