Aspect Medical to Report First Quarter 2009 Results on April 29, 2009

Aspect Medical Systems, Inc. (NASDAQ: ASPM) will report earnings results for the 2009 first quarter on Wednesday, April 29, 2009. Following the earnings announcement that day, the Company will host a conference call and live webcast at 10:00 a.m. Eastern Time for all interested parties, including financial analysts, portfolio managers, individual investors and members of the press. To participate in the call, please dial 800-510-9836 (domestic), 617-614-3670 (international), passcode: 28127608 or access the webcast at www.aspectmedical.com on the Investor page, or at www.earnings.com. Telephone replays will be available by dialing 888-286-8010 (domestic), or 617-801-6888 (international), access code 21615328. The webcast replay will be available from April 29, 2009 to May 07, 2009.

About Aspect Medical Systems, Inc

Aspect Medical Systems, Inc. (NASDAQ: ASPM) is a global market leader in brain monitoring technology. To date, the Company’s Bispectral Index (BIS) technology has been used to assess approximately 31 million patients and has been the subject of over 3,100 published articles and abstracts. BIS technology is installed in approximately 80 percent of hospitals listed in the July 2008 U.S News and World Report ranking of America’s Best Hospitals and in approximately 71 percent of all domestic operating rooms. In the last twelve months, BIS technology was used in approximately 19 percent of all U.S. surgical procedures requiring general anesthesia or deep sedation. Aspect Medical Systems has OEM agreements with nine leading manufacturers of patient monitoring systems. The Company is also investigating how other methods of analyzing brain waves may aid in the diagnosis and management of neurological diseases, including depression and Alzheimer’s disease. For more information, visit Aspect’s website at http://www.aspectmedical.com.