Advanced Imaging of Cerebrospinal Fluid Using Doppler Functional Ultrasound
Restricted (Penn State Only)
- Author:
- Yong, Katelyn
- Area of Honors:
- Biomedical Engineering
- Degree:
- Bachelor of Science
- Document Type:
- Thesis
- Thesis Supervisors:
- Sri-Rajasekhar Kothapalli, Thesis Supervisor
Nanyin Zhang, Thesis Honors Advisor
Xiao Liu, Faculty Reader - Keywords:
- MATLAB
Cerebrospinal Fluid
Functional Ultrasound
Doppler Effect - Abstract:
- Cerebrospinal Fluid (CSF) plays a pivotal role in maintaining central nervous system homeostasis. Consequently, CSF imaging has become a valuable tool in both research and clinical contexts, offering insights into various neurological conditions. Although brain imaging with Doppler ultrasound-based modalities occasionally reveals CSF, the underlying reasons for its visibility remain unclear. Given practical challenges and limitations associated with the most common imaging modalities, MRI and CT imaging, this research investigates why CSF could be imaged in certain scenarios. A digital simulation was developed to model brain vasculature and CSF flow. Then, phantoms were designed to test CSF parameters, including velocity, viscosity, composition, and turbulence in attempts to investigate why CSF is imaged in certain cases: hydrocephalus, multiple sclerosis, amyotrophic lateral sclerosis, and glioblastomas. Using a Verasonics 14 MHz ultrasound probe, power Doppler images were captured and reconstructed with average pixel intensity serving as a marker for signals interacting with different CSF parameters. Results indicate that increased protein concentration exhibits a positive relationship with the average pixel intensity of PDI, and turbulent flow exhibits a negative relationship with average pixel intensity. Conversely, while there are similar trends for velocity and viscosity's effect on pixel intensity, it is unable to definitively conclude them as contributing factors in CSF imaging. Understanding why CSF can be imaged, using a hand-held ultrasound probe with high spatial and temporal resolutions, provides valuable insights into how CSF is imaged under specific circumstances. This knowledge could potentially aid in imaging under certain brain diseases affected by CSF. In summary, this study enhances our understanding of CSF imaging, providing valuable insights for clinical practice and future research.