Courtney Whilden

Courtney is an undergraduate neuroscience student at Johns Hopkins, and she began in the Marsh lab in August of 2017. Her interests in the lab focus on patient perception of recovery. She is currently working on a study that addresses the relationship between patient-reported outcomes of recovery and objective measurements of cognitive recovery after stroke. Courtney has also assisted in the implementation of patient surveys in the clinic that assess patient expectations for recovery.

Courtney currently works in the Brown Lab, investigating circuits of the neocortex. She plans on graduating in 2020 and going on to pursue her PhD in Neuroscience.

Karen Chen, BA

Karen started out doing research in the Marsh lab as an undergraduate for two summers in 2014 and 2016. She graduated from Case Western Reserve University with her Bachelors of Arts in Biology and Psychology in 2017. She will be attending medical school at Penn State College of Medicine in the summer of 2018.

Karen’s time in the Marsh lab has culminated in one first-author publication, two middle-author publications, and two posters (presented at the 2015 American Academy of Neurology Annual Meeting, moderated poster at the 2018 International Stroke Conference). Her first project examined the added utility of CTA in assessing dizzy patients for posterior circulation ischemia. Results showed that the presence of calcium on CTA does not significantly increase the ability to predict stroke; a vascular risk assessment and neurological exam should remain the standard evaluation for risk-stratifying ischemia in dizzy patients. Her second study is looking at the factors associated with post-stroke fatigue and how they evolve from the early to chronic phases of recovery.


  1. Chang A, Llinas EJ, Chen K, Llinas RH, Marsh EB. Shorter intensive care unit stays?: The majority of post-intravenous tPA (tissue-type plasminogen activator) symptomatic hemorrhages occur within 12 hours of treatment. Stroke 2018;49(6):1521-1524. Click to read article

  2. Marsh EB, Lawrence E, Hillis AE, Chen K, Gottesman RF, Llinas RH. Pre-stroke employment results in better patient-reported outcomes after minor stroke. Clinical Neurology and Neurosurgery 2018;165:38-42. Click to read article

  3. Chen K, Schneider ALC, Llinas RH, Marsh EB. Keep it simple: vascular risk factors and focal exam findings correctly identify posterior circulation ischemia in “dizzy” patients. BMC Emergency Medicine 2016;16(1):8-16. Click to read article


Cathy Cao, PharmD

Dr. Cathy Cao collaborated with the lab as a pharmacy resident at Johns Hopkins Bayview, exploring the role of international normalized ratio (INR) in predicting ischemia. She is currently the Oncology Pharmacy Specialist at the Dana-Farber Cancer Institute.


Cao C, Martinelli A, Spoelhof B, Llinas RH, Marsh EB. In potential stroke patients on warfarin, the international normalized ratio predicts ischemia. Cerebrovascular Diseases EXTRA 2017;7(2):111-119.
Click to read article


Gabriel Casella, BA

As an undergraduate at Johns Hopkins, Gabriel investigated how commonly isolated aphasia was caused by ischemia and found an alternative diagnosis in the majority of cases. He is currently an IRTA Fellow at the National Institute of Aging and applying to MD/PhD programs. 


Casella G, Llinas RH, Marsh EB. Isolated aphasia in the emergency department: the likelihood of ischemia is low. Clinical Neurology and Neurosurgery 2017;163:24-26.
Click to read article


Martin Chacon-Portillo, MD

Dr. Martin Chacon-Portillo spent nearly a year with the Marsh lab investigating the association between cerebral microbleeds and hemorrhage after IV tPA and showed that the risk for symptomatic hemorrhage was low. This academic year, he will be a medical resident at the University of Arizona.


Chacon-Portillo MA, Llinas RH, Marsh EB. Cerebral microbleeds shouldn't dictate treatment of acute stroke: a retrospective cohort study evaluating risk of intracerebral hemorrhage. BMC Neurology 2018;18(1):33.
Click to read article


Emma Kaplan, BA

Emma worked in the Marsh lab as an undergraduate at Penn, investigating the association between substance abuse and intracranial hemorrhage. She is currently a medical student at the University of Maryland.


Kaplan EH, Gottesman RF, Llinas RH, Marsh, EB. The association between specific substances of abuse and subcortical intracerebral hemorrhage versus ischemic lacunar infarction. Frontiers in Neurology, 2014;5:174.
Click to read article


Edward Llinas

Edward worked in the Marsh lab the summer before his senior year of high school investigating the timing of symptomatic hemorrhage after treatment with IV tPA. He is an undergraduate student at Duke University. 


Chang A, Llinas EJ, Chen K, Llinas RH, Marsh EB. Shorter intensive care unit stays?: The majority of post-intravenous tPA (tissue-type plasminogen activator) symptomatic hemorrhages occur within 12 hours of treatment. Stroke 2018;49(6):1521-1524.
Click to read article


Richa Sharma, MD, MPH

Dr. Richa Sharma was part of the lab during her Neurology Residency at Johns Hopkins. Her areas of interest included the role of collaterals in predicting outcome and post-stroke cognitive impairment. She is currently a Stroke Fellow at the Massachusetts General Hospital in Boston.


Sharma R, Llinas R, Urrutia V, Marsh EB. Collaterals predict outcome regardless of time last known normal. Journal of Stroke and Cerebrovascular Diseases 2018;27(4):971-977.
Click to read article