Through the Directed Research for Undergraduates in Mathematics and Statistics (DRUMS) summer program, my team and I focused on Chronic Thromboembolic Pulmonary Hypertension (CTEPH). This disease is distinguished by lesions (blood clots) in the lungs and high blood pressure. While surgery is possible, limitations to modern medicine allow for only three lesions to be removed before it becomes too dangerous for the patient. Although not yet realized, our goal was to simulate lesion removal and blood flow in the pulmonary arteries to find the best lesions to remove. We used CT scans of the chest to create 3D representations of the pulmonary arteries, constructed networks of these vessels, and ran fluid dynamics simulations to compute the blood flow and pressure in the pulmonary arteries. My role in this project was to fix the 3D junction placement. Centerline extraction allowed us to interpret the vessels as 1-dimensional, but the software we used often placed the end of vessels in the wrong place. I used thresholds and weighted averages to develop an algorithm which moved the end of vessels into a more reasonable location. Ultimately, junction adjustment improved the output from simulations so that it resembled known pressure and flow measurements. From what we accomplished over the summer, we published a paper and presented our findings at the 2024 Joint Mathematics Meetings (poster and publication below).