Date of Award

January 2019

Document Type


Degree Name

Medical Doctor (MD)



First Advisor

Xenophon Papademetris


Twin-to-twin transfusion syndrome is a potentially fatal disease of placental vasculature in twin pregnancies. It is treated with fetoscopic laser photocoagulation surgery, a procedure in which a surgeon uses an endoscope to find and cauterize abnormal vascular anastamoses on the placental surface. However, even after surgery, mortality remains as high as twenty to forty-eight percent, largely due to anastamoses being missed during the operation. Many technical challenges contribute to anastamoses being missed, including poor endoscopic image quality and a limited field of view. Any tools capable of addressing these challenges would be clinically valuable. This thesis presents the design and validation of a computer assistance system for fetoscopic laser surgery with three major features: enhancement of endoscopic video, automatic detection and localization of blood vessels, and automatic stitching of endoscopic video frames into a panoramic map of the placental surface.


This thesis is restricted to Yale network users only. It will be made publicly available on 06/01/2022