Via http://www.ttinet.com/rsvk/family/vankeuren.html
The first Van Keuren in America was Matthys Jansen van Keulen (Ceulen), the Patroon of Zwaanendal. He was one of the directors of the Dutch West Indies Company, which bought Manhattan Island from the Indians.
Matthys married Margariet Hendricks, and they had four children, including two sons, Jan Matthysen and Matthys Matthysen. Jan Matthysen's descendants kept the patrynomic Jansen and use that name today. Matthys Matthysen's sons kept the name "van Keulen", changing the "l" to an "r" for unknown reasons, and all Van Keurens in America today are descended from Matthys Matthysen and his father Matthys Jansen van Keulen.