| # | Name | Duration |
|---|---|---|
| 1 | Dr. Jeannie Fitzgerald | February 2013 - November 2016 |
| 2 | Dr. Daniel Howard | April 2012 - February 2013 |
| 3 | Dr. Tom Arbuckle | September 2010 - August 2013 |
| 4 | Dr. John Sturdy | September 2007 - December 2010 |
| 5 | Dr. Miguel Nicolau | September 2006 - September 2007 |
| 6 | Dr. Atif Azad | September 2002 - September 2009 |