NORWOOD, Mass.--(BUSINESS WIRE)--Aspect Medical Systems, Inc. (NASDAQ: ASPM) today announced that it has repurchased, in privately negotiated transactions, an aggregate of $15 million face value of its 2.5% Convertible Senior Notes due 2014, for aggregate consideration of approximately $9 million in cash, including accrued interest. In June 2007, Aspect issued $125 million of its 2.5% Notes. As a result of these and prior repurchases, $100 million of the 2.5% Notes remain outstanding.