Corneal ectasia is a disorder that distorts vision by thinning and bulging the cornea. Severe cases often require surgical implants. The sponsor, a medical technology company, has developed a femtosecond laser system to create corneal surgery incisions. The Clinic team was tasked with prototyping a touchscreen-based graphical user interface (GUI) for intuitive treatment planning. Based on user studies and surgeon interviews, this GUI allows surgeons to draw incision shapes on scans of patients’ eyes and export them into the laser system.