Authors: Mary Amann
Fifteen years ago, the training path for vascular neurosurgery was paved mainly by residency training, and for some, augmented with fellowship training. The completion of formal neurovascular training essentially meant it was time for the neurosurgeon to put their training into clinical practice. At that time, vascular neurosurgery was less complex to organize than it is today, as the lines of clinical responsibility with respect to the provider of vascular service were drawn much more clearly.
The substantial evolution of devices coinciding with the advancement of clinical treatments in vascular neurosurgery has drastically changed the neurovascular field in a relatively short period of time. Endovascular or neuro-interventional techniques have markedly increased the “envelope of patients” that can be treated safely.
The literature indicates that the ratio of open surgery procedures compared to those performed endovascularly has shifted significantly since 2002, primarily due to the results of a now landmark study that focused on intracranial aneurysm outcomes of the two treatments. The International Subarachnoid Aneurysm Trial (ISAT) indicated that a ruptured aneurysm had better outcomes when treated endovascularly. Published data has consistently indicated that 2007 is the year when the two types of procedures crossed paths; at that time, there was an approximate 50 percent split in procedures between open and endovascular—just five years after ISAT. The trend toward endovascular treatment continued, and between 2007 and 2015 data indicated that 70 percent of procedures were being done endovascularly as compared to 30 percent as open surgery. The fallout is the dispersion of neurovascular care across multiple disciplines. Simply stated, the ability to treat neurovascular patients has expanded significantly in both technique and sub-specialty.
Image 1: Stent Retriever
In February 2015, Nature published the results from five clinical trials that made use of endovascular treatment for stroke patients, and in all five trials, the use of thrombectomy within the first six hours was shown to provide better outcomes. As a result of these trials, the preferred treatment for patients with severe strokes changed, revolutionizing the care provided to stroke patients. Since about 1996, stroke patients have typically been treated first with tPA, a clot-dissolving activator. However, the 2015 studies showed that although tPA is effective for smaller strokes, for large blockages, it dissolved the clot less than a third of the time. In these studies, a clot-removal device called a stent retriever or “stentriever” (Image 1) was used to go into the brain and grab the clot. Results showed that these devices reopened the artery 80 to 90 percent of the time, which led the American Heart Association to give the treatment its strongest recommendation and issue new guidelines in June 2016. This is just one example of how the “tree of knowledge” has, and is, continuing to grow at an extraordinary pace for neurosurgeons.
This treatment change has significantly impacted who participates in the care of ischemic stroke patients, giving neurosurgeons access to a whole new patient population. Historically, stroke neurologists have administered tPA within the first three to four hours of onset. Now, stent retrievers can be administered by endovascular trained neurosurgeons, interventional neuroradiologists, or interventional neurologists. Up to 20,000 stent thrombectomies are expected to be done this year, which is twice as many as last year. Companies who produce the stent retrievers are projecting that as many as 60,000 acute stroke patients will ultimately receive the procedure. Neurosurgery will be challenged to work collaboratively with radiology and neurology, while at the same time expanding the neurosurgical repertoire. Equally important is continuing to lead the management of patients with cerebrovascular disease, despite sharing this responsibility with other specialties.
It is evident that changes in neurovascular treatment have necessitated reflection on sub-specialty education and training requirements for neurovascular practice. Just this past year, the American Board of Neurological Surgery (ABNS), with support from the Senior Society, recognized the need for a sub-specialty vascular certification. Leaders from neurosurgery, neurology, and neuroradiology came together to develop a sub-specialty certification exam. This exam will be administered for the first time in August 2017. The sub-specialty knowledge that is now required in neurosurgical training programs has led residency programs to reevaluate their curriculums and clinical rotations. Disciplines of training such as interventional and angiographic treatments should now be considered earlier during residency training in order to ensure that the necessary and relevant neurosurgical sub-specialty training occurs at the right time, and adds value to the continuum of neurosurgical training. Residency training programs will need to be flexible, as change is occurring at rapid pace in the neurosurgical field.
From a business perspective, what does the evolution of vascular neurosurgery mean for practice administrators? Historically, vascular neurosurgery patients were sent to large academic centers where they received open or closed treatment for their cerebrovascular disorder. Today, more of these patients, especially ischemic stroke patients, are being treated at community hospitals. Based on the financial benefits associated with these patients, community hospitals are hiring endovascular trained neurosurgeons, interventional radiologists, and interventional neurologists. Practice administrators will need to identify growth opportunities in key areas and become experts in understanding market trends and revenue streams. Developing strategic initiatives with hospital partners will lead to competitive, successful centers. Understanding Stroke Designation versus Comprehensive Stroke Center, identifying expansion opportunities in telemedicine, determining faculty recruitment needs, knowing competitors’ strategies, and developing relationships with EMS will all be critical elements for future success.
< Note: The authors acknowledge and appreciate the input received for this article from Dr. Ralph G. Dacey, Jr, Dr. Gregory J. Zipfel, Dr. B. Gregory Thompson, and Dr. Aditya Pandey.
NERVES (Neurosurgery Executives’ Resource Value and Education Society) was established with the purpose of helping neurosurgery practice managers and administrators network, combine resources to gather information, and learn from their colleagues about how to build stronger practices.
THE SUCCESS OF THE STENT RETRIEVER HAS SIGNIFICANTLY IMPACTED WHO PARTICIPATES IN THE CARE OF ISCHEMIC STROKE PATIENTS, GIVING NEUROSURGEONS ACCESS TO A WHOLE NEW PATIENT POPULATION.