Claim: Gruessner was born in 1957 in Mainz, Germany and completed medical school at the Johannes Gutenberg University and  he was awarded “summa cum laude” for his doctoral thesis.
Evidence: Gruessner was born in 1957 in Mainz, Germany and completed medical school at the Johannes Gutenberg University. In 1983, he was awarded "summa cum laude" for his doctoral thesis.