<human>:  Who invented the CT scan?
<bot>: The CT scan was invented by a team of doctors at Johns Hopkins University in the early 1950s. The first patient to undergo a CT scan was a man who had a tumor in his brain. The doctors wanted to see if the tumor was cancerous, so they performed a CT scan. The CT scan showed that the tumor was cancerous, and the doctors were able to remove the tumor surgically. The CT scan is still used today for many different types of scans, including brain scans.