Brain Stiffness as a Predictor of Chronic Subdural Hematoma Characteristics and Tissue Reexpansion

PROJECT SUMMARY Chronic subdural hematoma (CSDH) is one of the most common types of intracranial hemorrhage, affecting 3.4-5/100,000 per year in the general population and 60-80/100,000 aged 65+ and its incidence is rising in the older population. Treatment is performed by draining the hematoma, but as many as 30%

of the cases reform hematomas with a mean timeline of about 1.5 months. Previous studies have worked to find clinical biomarkers to predict risk of hematoma and its recurrence so that the clinical care team can focus their efforts on these more complex cases. Previously identified biomarkers include age, hematoma

density (as viewed on a CT scan), and blood markers of inflammation; however, another significant factor is the subdural space and lack of reexpansion of tissue after treatment. Previous literature using invasive methods has suggested that the elastance of the brain surface around the hematoma may provide a strong

prediction of the ability of the brain to expand to fill the space of the evacuated hematoma. In this project, we will leverage recently developed magnetic resonance elastography (MRE) methods that quantitatively and non-invasively measure the brain mechanical properties of stiffness and damping ratio to correlate

with characteristics of the hematoma (size and density) along with reexpansion of the brain 1 month after treatment. We will examine a set of 40 patients with a CSDH diagnosis, collecting standard clinical measures of hematoma size, density, clinical symptoms, and blood markers of inflammation. In addition,

we will collect a high-resolution MRE data set 1 month after treatment that will provide spatial maps of stiffness and damping ratio of the patient’s brain. We will examine the mechanical properties of the brain in areas adjacent to the hematoma, along with a contralateral control area, to determine the correlative

value of these measures for hematoma size and density along with brain tissue reexpansion. We will also examine the relationships between brain mechanical properties and the other clinical biomarkers of recurrence from previous literature through a factor analysis to determine the correlations with other

measures and the uniqueness of the information provided through MRE for this condition. This line of research will have an important positive impact because it has the potential to provide a strong predictor of brain reexpansion after treatment for CSDH and hence risk of recurrence. The project will lay the

foundation for more individualized treatments in complex cases that are likely to recur.