American Heart Association

author interview

Author Interview: Dr. Eva Mistry on “Predicting 90-Day Outcome After Thrombectomy: Baseline-Adjusted 24-Hour NIHSS Is More Powerful Than NIHSS Score Change”

Dr. Eva Mistry
Dr. Eva Mistry

A conversation with Dr. Eva Mistry, MBBS, MSCI, Assistant Professor of Clinical Neurology and Rehabilitation, University of Cincinnati, on predicting 90-day outcome following thrombectomy.

Interviewed by Dr. Yasmin N. Aziz, MD, T32 Stroke Fellow, University of Cincinnati.

They will be discussing the paper Predicting 90-Day Outcome After Thrombectomy: Baseline-Adjusted 24-Hour NIHSS Is More Powerful Than NIHSS Score Change,” published in the August 2021 issue of Stroke.

Dr. Aziz: How did the idea behind this paper come to fruition?

Dr. Mistry: To help emphasize the importance of choosing ideal surrogate markers and their correct definitions. When we are developing tools to identify most efficacious acute stroke therapies that improve patient outcomes, and the surrogate outcome measures that we use to predict these patient-centered outcomes are flawed, then all that follows will be flawed as well. Ultimately, there is a real need for solid surrogate markers in acute stroke studies. NIHSS-based surrogate outcome measures are widely used in acute stoke trials. However, they are defined heterogeneously. With the paper, we wanted to establish the pros and cons of using various definitions NIHSS-based surrogate markers, and especially to show how each of them predict the patient-centered outcomes of 90-day modified Rankin Scores.

Author Interview: Dr. Tharani Thirugnanachandran on “Anterior Cerebral Artery Stroke: Role of Collateral Systems on Infarct Topography”

Dr. Tharani Thirugnanachandran
Dr. Tharani Thirugnanachandran

A conversation with Dr. Tharani Thirugnanachandran, MBChB, stroke researcher, Monash University, Victoria, Australia.

Interviewed by Dr. Andy Lim, MBA, emergency physician, Monash Medical Centre, Victoria, Australia.

They will be discussing the article “Anterior Cerebral Artery Stroke: Role of Collateral Systems on Infarct Topography,” published in Stroke.

Dr. Lim: Dr. Thirugnanachandran, on behalf of the Blogging Stroke team, it is a pleasure to welcome you to this author interview regarding your publication in Stroke that explored the role of leptomeningeal anastomoses in influencing infarct topography after anterior cerebral artery stroke. Can I start by asking you to give us a brief summary of what you did?

Dr. Thirugnanachandran: Thank you, Dr Lim. Anterior cerebral artery stroke is far less common than middle cerebral artery stroke. So comparatively less attention has been given to it in the literature. Much of our current understanding about it has come from older works taken postmortem or poststroke. In contrast to prior studies, our study was able to give us an insight into what happens to this arterial territory at stroke onset with the use perfusion imaging and a computer model.

Author Interview: Dr. Rajat Dhar on “Automated Quantification of Reduced Sulcal Volume Identifies Early Brain Injury After Aneurysmal Subarachnoid Hemorrhage”

Dr. Rajat Dhar, left, and Dr. Saurav Das
Dr. Rajat Dhar, left, and Dr. Saurav Das

A conversation with Dr. Rajat Dhar, MD, Associate Professor of Neurology and Neuro-critical care, Washington University School of Medicine, St. Louis, MO.

Interviewed by Dr. Saurav Das, MD, Fellow in Vascular Neurology, Washington University School of Medicine, St. Louis, MO.

They will be discussing the article “Automated Quantification of Reduced Sulcal Volume Identifies Early Brain Injury After Aneurysmal Subarachnoid Hemorrhage,” published in Stroke.

Dr. Das: Dr. Dhar, on behalf of the Blogging Stroke team, we welcome you to this author interview.  I read with great interest your paper pertaining to the automated estimation of selective sulcal volume (SSV) to quantify global cerebral edema (GCE) from early brain injury (EBI) in aneurysmal subarachnoid hemorrhage (aSAH). This is an important paper as our understanding of clinical outcomes following aSAH is shifting from vasospasm induced delayed cerebral ischemia (DCI) towards GCE from EBI. Also, we currently do not have the tools to measure GCE accurately.

This research uses a “deep learning-based approach” for the analysis of serial CT scans to measure SSV. Many of our readers may not be familiar with the use of artificial intelligence (AI) in image analysis. I will begin by requesting you to explain what deep learning is.

Dr. Dhar: Applications of artificial intelligence, specifically machine learning, to the realm of biomedical image analysis have been growing exponentially over the past few years. AI is well-suited to image analysis because, at its core, machine learning seeks to find patterns in data, and images are just patterns of intensity and location data. Machine learning algorithms can be trained to learn from labeled data. For example, to determine what regions of a scan represent blood vs. brain vs. CSF is called a segmentation task. We can use machine learning to perform a segmentation task on new imaging data. AI algorithms can perform image analysis in a fast and reproducible way, eliminating the need for time-intensive human input. They can measure volumes of similar brain structures over serial time points more objectively and accurately than one or more humans may be able to.

Author Interview: Dr. Masafumi Ihara on “Oral Carriage of Streptococcus mutans Harboring the cnm Gene Relates to an Increased Incidence of Cerebral Microbleeds”

Dr. Masafumi Ihara, left, and Dr. Saurav Das

An  interview with Dr. Masafumi Ihara, MD, PhD; Head, Department of Neurology, National Cerebral and Cardiovascular Center, Osaka, Japan.

Interviewed by Dr. Saurav Das, MD; Fellow in Vascular Neurology, Washington University School of Medicine, St. Louis.

They will be discussing the article “Oral Carriage of Streptococcus mutans Harboring the cnm Gene Relates to an Increased Incidence of Cerebral Microbleeds,” published in the December 2020 issue of Stroke.

Dr. Das: Dr. Ihara, on behalf of the Blogging Stroke team, it is my pleasure to welcome you to this author interview about your publication in Stroke regarding the association between CNM gene-positive Streptococcus mutans and increased incidence of cerebral microbleeds. Given Streptococcus mutans is a common pathogen associated with dental caries, it is a potential treatment target to prevent increase in cerebral microbleeds.

Many of our readers come from a stroke background and may not be as familiar with oral pathology. It will be of interest to start by discussing some common oral pathogens implicated in cerebrovascular disease. Also, what is specific about Streptococcus mutans, and particularly the ones positive for CNM gene?

Dr. Ihara: More than 500 bacterial species have been estimated to exist in the oral cavity, and many remain to be identified and characterized. Of all the known pathogenic oral bacteria, a few have been linked to cerebrovascular diseases. Our co-investigator Prof. Nakano reported that certain strains of Streptococcus mutans (S. mutans) are potential risk factors for intracerebral hemorrhage in stroke-prone spontaneously hypertensive rats and mice with photochemically induced middle cerebral artery occlusion.1 This corresponds with findings showing periodontal infections to be risk factors for stroke, and that S. mutans is detected in 100% of samples of atherosclerotic plaques. S. mutans is a major pathogen in dental caries that can cause bacteremia by dental procedures, such as tooth extraction and periodontal surgery, or even tooth brushing in daily life. S. mutans is well known to be responsible for infective endocarditis. The hemorrhage-causing S. mutans strains express collagen-binding protein Cnm on their cell surface, enabling them to attach to exposed collagen fibers on the surface of damaged blood vessels and prevent platelet activation, thereby, leading to hemorrhages. Another dental bacterium, Porphyromonas gingivalis (P. gingivalis), is also found in atherosclerotic plaques and has been linked to the increased risk of ischemic stroke. P. gingivalis adheres to and infects endothelial cells not only to increase the expression of endothelial adhesion molecules and promote monocyte/macrophage infiltration, but also to produce cysteine proteinase gingipains, which activate protease-activated receptors-1 and -4 on platelets to induce platelet aggregation. Thus, infection from P. gingivalis could cause small vessel disease pathology through thrombotic occlusion and BBB disruption through inflammation.

World Stroke Day: Interview with Dr. Anna Bersano on the Impact of the COVID-19 Pandemic on Stroke Care in Italy

Dr. Anna Bersano
Dr. Anna Bersano

An interview with Dr. Anna Bersano, MD, PhD, at the Cerebrovascular Unit of Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy, about the impact of the COVID-19 pandemic on stroke care in Italy.

Interviewed by Francesca Tinelli, MCs, rare cerebrovascular disease fellow at Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy.

Dr. Tinelli: First of all, I present you Dr. Anna Bersano, the neurologist I work with, and I would like to thank Anna for agreeing to do this interview. 

Anna is a stroke neurologist with long-term expertise in cerebrovascular diseases, particularly in genetics of monogenic and complex stroke diseases, combining research with an active practice as a vascular care neurologist. She coordinated several studies on genetics of stroke, such as the Lombardia GENS study on stroke monogenic disease and the SVE-LA study on genetics of small vessel disease and lacunar stroke. Recently, she implemented an Italian network for the study of Moyamoya disease named GE-NO-MA (Genetics of Moyamoya Disease) and an Italian network for the study of Cerebral Amyloid Angiopathy (SENECA project). 

Dr. Bersano: Thank you for discussing this relevant and critical topic in the current situation.

Dr. Tinelli: What is the correlation between SARS-CoV2 and cerebrovascular diseases?

Dr. Bersano: It is well known that SARS-CoV2 invades human respiratory epithelial cells through its S-protein and ACE2 receptor on human cell surface. Then, the virus can spread from the respiratory tract to the central nervous system, causing possible neurological complications. A recent study on 214 Chinese COVID-19 patients reported acute cerebrovascular events in 5.7% of COVID-19 patients. However, the exact relationship between SARS-CoV2 and stroke is unclear. Patients affected by COVID-19 have been observed to have a higher risk of cerebrovascular events, probably due to the activation of coagulation and inflammatory pathways, which lead to cardiovascular and thrombotic complications, or to cardioembolic causes.

Author Interview: Dr. Bruce Ovbiagele on “HEADS-UP: Understanding and Problem-Solving: Seeking Hands-Down Solutions to Major Inequities in Stroke”

A conversation with Dr. Bruce Ovbiagele, MD, MSc, MAS, MBA, Professor of Neurology, University of California, San Francisco.

Interviewed by Dr. Saurav Das, MD, Fellow in Vascular Neurology, Washington University School of Medicine, St. Louis.

They will be discussing the article “HEADS-UP: Understanding and Problem-Solving: Seeking Hands-Down Solutions to Major Inequities in Stroke,” published in November 2020 issue of Stroke. The article is part of a Focused Updates series of articles on topics related to health equity.

Dr. Das: Dr. Ovbiagele, at the outset, I want to thank you on behalf of the Blogging Stroke team for organizing this timely and reflective series of articles. I read with enthusiasm your introduction to the series. Thanks for finding time for this interview.

Dr. Ovbiagele, COVID-19 and the killings of unarmed Black individuals by police recently have brought to the forefront discussions about pre-existing racial disparities in stroke care. However, the idea of HEADS-UP was envisaged even before these extenuating circumstances. Please throw some light on the origins of the idea.

Dr. Ovbiagele: My co-chair, Dr. Amy Towfighi, and I have been involved in stroke disparities research for a while (Amy doing work with the Latinx population in Los Angeles, and I doing work with people of African ancestry in South Carolina and Sub-Saharan Africa), and had lamented about both the lack of successful interventions and a clear pipeline of next generation stroke disparities researchers. We observed that with changing U.S. demographics and anticipated worsening of stroke inequities, stroke disparities research and publications seemed to mostly focus on repeatedly pointing out the existence and magnitude of racial/ethnic disparities, that the stroke disparities community was not routinely connected or integrated in a sustainable way, and that early career individuals interested in stroke disparities did not appear to have an established avenue through which to nurture that interest into a successful independent academic career. We thought that if we could bring key stakeholders together in a forum that routinely informs and inspires established and budding stroke disparities researchers to better solutions and greater heights, we might be able to accelerate the pace of discoverers and discoveries. We approached the American Stroke Association, National Institute of Neurological Disorders and Stroke, and several of our esteemed research colleagues about the idea, and then collectively planned and implemented the inaugural Symposium.

Pictured, from left to right, at the International Stroke Conference 2020, are Dr. Amy Towfighi, Dr. Bruce Ovbiagele, Dr. Ralph Sacco, and Ms. Adrienne Kenton, daughter of Dr. Edgar Kenton III, after whom the Kenton Award is named.
Pictured, from left to right, at the International Stroke Conference 2020, are Dr. Amy Towfighi, Dr. Bruce Ovbiagele, Dr. Ralph Sacco, and Ms. Adrienne Kenton, daughter of Dr. Edgar Kenton III, after whom the Kenton Award is named. Photo provided, with permission, by Dr. Ovbiagele.

Dr. Das: Dr. Ovbiagele, you have summarized in your introduction a series of key papers from the 2020 HEADS-UP symposium in Los Angeles, California. These papers explore biological and social determinants of disparities and explore multi-level interventions. However, neither of these categories have explored “racism,” individual or systemic, as a study variable in stroke research. What are your thoughts, and will this be addressed in the HEADS-UP symposium in 2021?

Author Interview: Prof. Marc Ribo on “Deep Learning Based Software to Identify Large Vessel Occlusion on Noncontrast Computed Tomography”

Prof. Marc Ribo
Prof. Marc Ribo

An interview with Prof. Marc Ribo, MD, PhD, Assistant Professor at the Stroke Unit/Department of Neurology at the Hospital Vall d’Hebron, Barcelona, Spain.

Interviewed by Dr. Vera Sharashidze, MD, Vascular Neurology Fellow, University of Miami.

They will be discussing the article “Deep Learning Based Software to Identify Large Vessel Occlusion on Noncontrast Computed Tomography,” published in the October 2020 issue of Stroke.

Dr. Sharashidze: First of all, thank you for taking time to discuss this very interesting article. What led you to become interested in this topic?

Prof. Ribo: My first interest in AI analysis of acute stroke imaging began when I met by coincidence with an expert engineer who wanted to use his skills to help stroke patients.

Author Interview: Dr. Mayank Goyal on “Challenging the Ischemic Core Concept in Acute Ischemic Stroke Imaging”

Dr. Mayank Goyal and Dr. Saurav Das
Dr. Mayank Goyal, left, and Dr. Saurav Das

A conversation with Mayank Goyal, MD, PhD, Professor of Radiology and Clinical Neurosciences, University of Calgary.

Interviewed by Saurav Das, MD, Fellow in Vascular Neurology, Washington University School of Medicine, St. Louis.

They will be discussing the topical review “Challenging the Ischemic Core Concept in Acute Ischemic Stroke Imaging,” published in October 2020 issue of Stroke

Dr. Das: Dr. Goyal, the Blogging Stroke team is happy to have you for an author interview today. Thanks for this provocative paper, which disrupts several currently accepted ideas that guide decision-making in stroke patients to make way for new innovation.

Let’s start by discussing the context in which this paper was conceptualized. The paper has a line-up of great authors, many considered visionaries in vascular neurology, across countries. Please tell us more about how this collaboration came into being.

Dr. Goyal: I have been thinking about the problem of defining ischemic core on baseline imaging for a long time. I noticed patients with a really bad-looking baseline CT, patients in which you would be inclined to call the whole MCA territory “core.” But when these patients went on to endovascular treatment and we managed to re-open the occluded vessel quickly, many of those did well, and their follow-up MRI scans showed that much of the parenchyma thought to be “core” was not actually damaged. More importantly, many of these patients did well clinically, resulting in a clinical-imaging mismatch. In addition, I was quite convinced that the so called “core” on CT perfusion was quite an exaggeration of the truth. In some ways, when many of the trials were being designed, they came in the aftermath of the Interventional Management of Stroke (IMS) 3 trial, and hence, people were over-conservative in their selection criteria. I then started talking to several of my collaborators and friends from all over the world, to see whether they felt the same way. This is when this collaboration was formed.

Author Interview: Drs. Diogo Haussen, MD, and Yasir Saleem, MD, on “Acute Neurological Deterioration in Large Vessel Occlusions and Mild Symptoms Managed Medically”

Diogo Haussen
Dr. Diogo Haussen
Dr. Yasir Saleem
Dr. Yasir Saleem

A conversation with Diogo Haussen, MD, Assistant Professor of Neurology, Emory School of Medicine/Grady Memorial Hospital, and Yasir Saleem, MD, Assistant Professor of Neurology, Baylor College of Medicine, on the approach to patients with large vessel occlusion (LVO) and mild symptoms.

Interviewed by Jennifer Harris, MD, stroke fellow, Columbia University, and Rachel Forman, MD, stroke fellow, Massachusetts General Hospital.

They will be discussing the article “Acute Neurological Deterioration in Large Vessel Occlusions and Mild Symptoms Managed Medically,” published in the May 2020 issue of Stroke.

Drs. Harris and Forman: Thank you for taking the time to speak with us on this important topic.  

Drs. Haussen and Saleem: Thank you for reaching out. It is a pleasure interacting with you.

Drs. Harris and Forman: As stroke fellows, we run into this scenario from time to time, and it is often a challenging decision that generates good discussion. What was the background for you in wanting to study this specific topic?

Drs. Haussen and Saleem: A common reason for neurological deterioration in patients presenting with mild strokes is the underlying presence of a large vessel occlusion. Importantly, neurological worsening in this setting has been associated with worse clinical outcomes. However, not all individuals with large vessel occlusion and mild presentation end up worsening. We have observed, in our original experience (Haussen DC et al. JNIS 2017 Oct;9(10):917-921), that >40% of patients with LVO medically managed had some degree of neurological deterioration. We wanted to evaluate the potential variables that could potentially predict neurological worsening within patients presenting with minor stroke symptoms and large vessel occlusion.

Author Interview: Dr. Eric Jouvent, MD, PhD, on “Cerebral Autosomal Dominant Arteriopathy With Subcortical Infarcts and Leukoencephalopathy”

Dr. Eric Jouvent
Dr. Eric Jouvent

A conversation with Dr. Eric Jouvent, MD, PhD, Professor of Neurology at Paris University. He is involved in acute stroke care in the stroke unit in Lariboisière Hospital in Paris. He holds a PhD in image processing.

Interviewed by Dr. Stephanie Lyden, MD, BS, a vascular neurology fellow at the University of Utah.

They will be discussing the article “Cerebral Autosomal Dominant Arteriopathy With Subcortical Infarcts and Leukoencephalopathy: Lessons From Neuroimaging.” Published in the January 2020 issue of Stroke, it is part of a Focused Updates in Cerebrovascular Disease series of articles on topics related to cerebral small vessel diseases.

Dr. Lyden: First of all, thank you for taking the time to discuss this important topic. What led you to become interested in studying CADASIL?

Dr. Jouvent: It was not really a choice at first. Residency in France is different than in the United States, where we first choose a city and then we move from department to department in that city. At the end of that time period, you hope to match in a department or with a team. At the end of my cycle, I matched with a team headed by Dr. Bousser, who identified the first family with CADASIL, in part because I was not only interested in stroke, but also in cognitive and behavioral alterations and in advanced MRI techniques, which are key aspects in small vessel diseases. This was how I started to become involved in CADASIL research.