​​​Neurointerventional Surgeons use advanced imaging and catheter-based techniques to provide minimally invasive treatments for many conditions of the brain and spine.
ABOUT DR. KAYAN
GET TO KNOW DR. KAYAN
Dr. Kayan is the medical director of Neurointerventional Surgery at Abbott Northwestern Hospital, part of Allina Health in Minneapolis. His practice philosophy is to provide the highest level of evidence-based, patient-centered neurointerventional care.
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The goal of this site is to help patients navigate often challenging neurological diagnoses that have safe and effective, minimally invasive, catheter-based treatments.
Professional Affiliations
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Society of NeuroInterventional Surgery, Senior Member
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American Society of Neuroradiology, Senior Member
Board Certification​
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Recognition of Focused Practice, CNS Endovascular Surgery, American Board of Neurological Surgery
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Certificate of Added Qualification, Neuroradiology, American Board of Radiology
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Board Certification, American Board of Radiology
Education
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Fellowship in Endovascular Surgical Neuroradiology, Washington University in St. Louis, 2012
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Residency in Radiology, Washington University in St. Louis, 2010
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MD, Washington University in St. Louis, 2005​
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What do neurointerventionalists treat?
What is a
Brain Aneurysm?
A brain aneurysm is a weak spot in the wall of a brain artery that bulges or balloons outward. Most commonly, brain aneurysms are saccular, meaning that they protrude outward from the artery and have a "neck"
Brain aneurysms can be treated endovascularly, using minimally invasive techniques, such as placing a basket-like device inside to secure the aneurysm and prevent it from rupturing. This technique is known as intra-saccular flow diversion.
Aneurysms that arise from the side of an artery can be treated with a braided tube, known as a flow diverter, that covers the opening to the aneurysm. This technique is known as intra-vascular flow diversion.
Regardless of treatment technique, or even if the aneurysm is treated at all, brain aneurysms require lifelong follow-up. Should an aneurysm recur, an endovascular solution is almost always available. We pride ourselves on extremely robust, compulsive long-term patient follow-up.
On the flip side, we have seen patients who have had open brain surgery for their aneurysm (and deemed "cured" by their neurosurgeon) come back years later with a life-threatening brain bleed. In our view, the often touted durability of open surgery is not a convincing proposition.
What is a
Subdural Hematoma?
A subdural hematoma is a collection of blood under the lining of the brain. While an acute subdural hematoma can be a neurosurgical emergency, these also have a tendency to become persistent. In such cases, a neurointerventional surgeon can perform a procedure known as middle meningeal artery embolization.
Chronic or persistent subdural hematomas are due to inflammation in the lining of the brain. The middle meningeal artery (MMA) supplies blood to the lining of the brain. By navigating a small catheter into this artery and performing an embolization, i.e. plugging it up, we are able to reduce the inflammation and allow the body to absorb the blood over the course of several weeks.
MMA embolization is an extremely safe and effective treatment for a previously difficult to handle problem.
What is
Carotid Artery Disease?
Carotid artery disease is a narrowing of the carotid arteries (the pulse you feel in your neck), usually due to atherosclerotic plaque.
Hariadhi, CC BY-SA 4.0, Wikimedia
We are finding that an increasing number of patients with carotid artery disease would benefit from angioplasty and stenting
NIH, public domain, Wikimedia
Before you choose to have your carotid artery treated, it may be worthwhile to have your case reviewed by a neurointerventional surgeon, particularly one with a neuroradiology training background.
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Below, you will find the odds of death, stroke or heart attack by 30 days after a carotid stenting procedure performed by physicians from various training backgrounds (from the original CREST trial, J Stroke Cerebrovasc Dis 2010). Physicians from a neuroradiology training background are the safest!
What is
Pulsatile Tinnitus?
Pulsatile tinnitus is a "whooshing" in your ear, in sync with your heartbeat. This can be caused by abnormalities of the blood vessels in and around the head. Two of the most common underlying conditions that neurointerventional surgeons treat are:​​
PK Sasidharan, CC BY 3.0, Wikimedia
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Idiopathic intracranial hypertension (IIH): high pressure in the fluid in and around the brain, which can be caused by venous sinus stenosis, a narrowing of the largest veins in the back of the head​​ (see arrow below for where this usually happens)
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Dural arteriovenous fistula (DAVF): abnormal connections between arteries (red arrow) and veins (blue arrow) in the lining of the brain, which can also cause bleeding in the brain
J Borden MD, CC BY-SA 2.5, Wikimedia
A series of tests, including lumbar puncture, cerebral venography with pressure measurements, and cerebral angiography, can help determine the cause and allow us to prepare a treatment plan.
Is there an
Identity Crisis?
Our field goes by other names, some more popular than others:
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Interventional Neuroradiology
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Neurointerventional Radiology
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Neuroendovascular Surgery
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Endovascular Surgical Neuroradiology
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Endovascular Neurosurgery
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Interventional Neurology
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Our professional society, the Society of Neurointerventional Surgery (SNIS), was founded in 1992 as the American Society of Interventional and Therapeutic Neuroradiology (ASITN). As the field evolved, the name was changed to reflect the three subspecialties of physicians who form its membership: interventional neuroradiology, endovascular neurosurgery, and interventional neurology.
What is Dr. Kayan's most commonly performed neurovascular intervention?
Treating Brain Aneurysms
Treating brain aneurysms has historically been described as possible using two general techniques:
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open brain surgery, aka "clipping"
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endovascular surgery, aka "coiling" -- note that the term "coiling" is like Kleenex. It is a holdover from the '90s. Today, in our practice, less than 10% of our aneurysms are treated with coils primarily.
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In 2026, discussing these techniques as two sides of the same coin is a false equivalence.
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In my 16 years of practice, we have found an endovascular solution to nearly 100% of aneurysms we have encountered.
Being confronted with a "surgical" aneurysm is an extremely rare occurrence, and in all likelihood, the morbidity of a proposed surgery would eclipse the morbidity of any endovascular approach, and certainly the risk of close observation.
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If you or a loved one is dealing with a complex brain aneurysm, which would you rather have?
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An elegant endovascular solution performed by a neurointerventional surgeon who does hundreds of these every year, perhaps a half dozen a week, who sees similar aneurysms again and again.
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Open brain surgery by a neurosurgeon who does only a few cases per year and is convinced that an aneurysm needs surgery because they are not aware of the safety of the latest endovascular techniques.​​​
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What two thing are most important in choosing a neurointerventionalist?
Experience and Expertise
When choosing a neurointerventional surgeon to treat your brain aneurysm, a few things are extremely important.
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How many aneurysms does he or she treat in a year?​
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What techniques does he or she use?​
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What are his or her success/complication rates?
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Dr. Kayan treats one of the highest volumes of brain aneurysms in the country. He has personally treated nearly 2,000 brain aneurysms using a minimally invasive endovascular approach. Using the latest devices, including both intra-saccular and intra-vascular flow diversion, his personal major complication rate is on the order of 1% or less.
Name a couple of commonly performed procedures that were not "mainstream" a decade ago.
MMA embolization
Venous sinus stent
MMA embolization is a safe and effective treatment for chronic or persistent subdural hematomas, previously a strictly neurosurgical disease.
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Venous sinus stenting can be a safe and effective treatment for pulsatile tinnitus and/or idiopathic intracranial hypertension (IIH).
