Michael Alexander, MD, vice chair of Neurosurgery and director of the Neurovascular Center and Endovascular Neurosurgery at Cedars-Sinai, on intracranial atherosclerotic disease (ICAD): whom it affects, how it’s treated and more.
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related article. I am Doctor Michael Alexander. I'm a neurosurgeon and Vice Chair of neurosurgery at Cedars Sinai Medical Center. ICAD is a term we use to describe cholesterol blockages in the brain arteries. So ICAD is an acronym for intracranial Aros disease and that can cause strokes. Most of the people with ICAD have certain risk factors. So there are smokers, they may have high cholesterol diabetes, obesity and sometimes a family history of cholesterol blockages in the arteries. So ICAD can affect any race or ethnicity. It has a higher incidence in Asians, Latinos and African Americans. Some patients may have no symptoms from ICAD in the early stages. So when there's a small amount of cholesterol blockage, you may have no symptoms at all. Uh as the blockage gets tighter and tighter, there's less blood flow getting to the brain. So patients may experience T I A S which is a temporary type of stroke where they may have temporary trouble with speaking, temporary numbness or weakness in their arms or legs or problems with balance or dizziness. And those can be the early warning signs of ICAD. Later on in the disease, patients may have a stroke which may have those similar symptoms where they have permanent problems, speaking permanent weakness, et cetera. And those are the symptoms we want to prevent. With some of the treatments that we have. Cedar Sinai has been assessing and treating patients with ICAD for many years. We were one of the first centers to have high resolution M R A imaging of the brain. And what that does is it specifically looks at the brain arteries with contrast using dye to see if there's any inflammation of the cholesterol plaque and see if patients are at high risk for having further strokes. We are also one of the first centers to run major uh national trials looking at stenting for ICAD. So trying to open up the blocked arteries in the brain with stents and using these techniques to prevent more strokes in the future. So, Cedar Sinai, we ran the first two uh FDA approved trials in the last decade uh called the Weave trial and the Woven Trial to look at stenting in patients who have high degree blockages in their brain arteries. Uh We also were the first center to use a technique called or indirect bypass. So opening up the skull and bringing in an artery to bring extra blood flow to the brain for patients who have very severe Icat disease. And we ran a clinical trial funded by the National Institute of Health. The N I H looking at that treatment for these patients, we did an interesting study this past year that was presented at the International Stroke Conference in Dallas that showed that the number of patients who had received a intracranial stent for ICAD had gone up five times from where it was about six years ago. And there weren't any other trials or uh major recommendations by major medical societies that uh indicated we should do that other than the weave and the Woven trial. So uh these two trials that Cedar Sign I ran that were multi institutional. So over 24 centers across the country gave physicians much more confidence in performing the stenting procedure in the select group of patients that we talked about earlier that met the criteria for stenting. And that study also showed that patient outcomes have been improving over that six year period. So not only are more patients getting the treatment but the patient outcomes are better than they were six years ago. So when the patients referred to us, we have a team approach to treating them or assessing them. So the uh stroke neurologists will do uh basic tests on their blood and perhaps some other imaging of the brain besides MRI such as C T Perfusion, which is a cat scan where we look at the blood flow to the brain to see if there's actually compromised blood flow in the area of the blocked artery. The neurosurgeons, neuro interventionists and neuro radiologists all help participate in both the assessment and treatment of the patient. So it's a true team approach. For most patients, this treatment prevents or reduces the number of strokes patients will have in the future for some patients that actually improves their neurologic condition. So particularly patients who present with dizziness or problems with balance, sometimes they have low blood flow to the back part of the brain called the cerebellum. And for those patients as soon as they have increased blood flow, they stop having dizziness and they have better balance. Uh just with the treatment, I think some of the questions that patients and their families have about ICAD is number one, are they a candidate for treatment? Because many patients are told that they aren't a candidate for any other treatment other than medical therapy. And that's not true. Uh So they want to know, are they a candidate? Secondly, patients want to know what the risks are with this type of treatment. There's risks with any type of treatment, even just medical therapy alone. But what we found from the weave trial is that the risk of doing the stent treatment is actually very low now compared to where it was 10 years ago. And so it is in a very good safety range for treatment. As long as the patient meets the criteria, if you've had a patient who's had a stroke or a T I A, and you've performed a study that shows they have ICAD or intracranial arthrosclerotic disease as a potential cause of that stroke. Please refer them to the Cedar Icad program for further evaluation.