Aspect Medical Systems Sponsors Cleveland Clinic Studies to Investigate Impact of Anesthetic Management Techniques on Patient Outcomes.

Studies to assess patient outcome effects of avoidance of deep anesthesia in at risk populations

NORWOOD, Mass. -- Aspect Medical Systems, Inc. (NASDAQ: ASPM) today announced the initiation of two studies being conducted with the Cleveland Clinic to investigate the impact of anesthetic management techniques on patient outcomes. The first study seeks to determine if avoidance of deep anesthesia, administration of steroids and control of blood sugar levels improves outcomes in patients undergoing major vascular surgery. The second study is designed to test the hypothesis that avoiding deep general anesthesia reduces cancer recurrence rates in women undergoing surgery for breast cancer. Both studies will utilize BIS monitoring to assess depth of anesthesia.

"Several recent studies have led to a growing interest within the medical community to better understand the potential long term adverse consequences associated with excessive anesthesia exposure, particularly of inhaled anesthetics," said Nassib Chamoun, president and CEO of Aspect Medical Systems. "The studies we are sponsoring with the Department of Outcomes Research in the Division of Anesthesiology, Critical Care Medicine and Comprehensive Pain Management at the Cleveland Clinic reflect our commitment to support research that further defines the role of BIS monitoring in helping clinicians control depth of anesthesia and improve the safety and quality of patient care."

The vascular study is expected to evaluate up to 900 patients scheduled for elective major vascular surgeries at Cleveland Clinic hospitals. Patients will be randomized to a surgical care protocol that includes administration of a steroid or placebo, intensive or conventional glucose management and lighter or deeper anesthetic management. Researchers will assess multiple outcome measures during and after surgery, including the incidence of major perioperative morbidity such as heart attack, as well as incidence of surgical complications, delirium, and quality of life.

Commenting on the vascular study, Daniel Sessler, MD, lead investigator and chair of the Outcomes Research Department in the Division of Anesthesiology, Critical Care Medicine and Comprehensive Pain Management at the Cleveland Clinic stated, "Previous research suggests that anesthetic management techniques may impact the body's inflammatory response to surgery. This study will rigorously compare the effects of three different anesthetic management strategies, used both alone and in combination, with the goal of understanding how we can minimize the body's inflammatory response and thereby improve patient outcomes."

The second Cleveland Clinic trial is expected to evaluate up to 1,100 breast cancer patients scheduled to undergo mastectomies. Patients will be randomly assigned to regional anesthesia/analgesia with sedation or light anesthesia, or to a full general anesthetic and morphine analgesia. Participants will be followed for up to 10 years to determine the rate of cancer recurrence or metastasis. BIS monitoring will be used to determine whether the depth of general anesthesia is related to patient outcomes.

"In a recent retrospective study, we found evidence that breast cancer patients who receive regional anesthesia during surgery appear to have better long term outcomes compared to those who receive general anesthesia, and a second retrospective study has shown similar results in patients with prostate cancer," said Dr. Sessler. "Our new study will test whether avoidance of general anesthesia can reduce risk of cancer recurrence and mortality in women undergoing breast cancer surgery. Additionally, we will determine whether cumulative time under general anesthesia with BIS values lower than 45 is associated with cancer recurrence in these populations."

More information about both trials is available at www.clinicaltrials.gov using identifiers NCT00433251 and NCT00418457.

About BIS Monitoring

Using a sensor placed on the patient's forehead, BIS monitoring translates information from the electroencephalogram (EEG) into a single number that represents each patient's level of consciousness. This number - the BIS value - ranges from 100 (indicating an awake patient) to zero (indicating the absence of brain activity). Using the BIS value to guide administration of anesthetic medication, in conjunction with other vital signs, allows clinicians to make better informed decisions to achieve optimal anesthesia.

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 more than 18.7 million patients and has been the subject of approximately 2,710 published articles and abstracts. BIS technology is installed in approximately 73 percent of hospitals listed in the July 2006 U.S News and World Report Ranking of America's Best Hospitals and in approximately 53 percent of all domestic operating rooms. In the last twelve months BIS technology was used in approximately 16 percent of all U.S. surgical procedures requiring general anesthesia or deep sedation. BIS technology is available in more than 160 countries. Aspect Medical Systems has OEM agreements with seven 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 Web site at http://www.aspectmedical.com.

Safe Harbor Statement

Certain statements in this release are forward-looking and may involve risks and uncertainties. There are a number of factors that could cause actual results to differ materially from those indicated by these forward-looking statements, including the Company's expectation that a potential outcome of the clinical studies will be to further define the role of BIS monitoring in helping clinicians control depth of anesthesia and improve the safety and quality of patient care. There are a number of factors that could cause actual results to differ materially from those indicated by these forward-looking statements. For example, the completion of one or both of the studies could be delayed and/or either trial could be unsuccessful as a result of various factors including delays in patient enrollment, lower than anticipated retention rates for patients in the trial, negative trial outcomes and the failure of one or both of the trials to adequately assess the impact of anesthesia management techniques on patient outcomes. There are additional factors that could cause the Company's actual results to vary from its forward-looking statements, including without limitation those set forth under the heading "Risk Factors" in the Company's Annual Report on Form 10-K for the fiscal year ended December 31, 2006, as filed with the Securities and Exchange Commission. In addition, any forward-looking statements represent the Company's views only as of the date of this press release and should not be relied upon as representing the Company's views as of any subsequent date. While the Company may elect to update forward-looking statements in the future, it specifically disclaims any obligation to do so, even if its expectations change. Therefore, you should not rely on these forward-looking statements as representing the Company's views as of any date subsequent to the date of this press release.

Aspect, Bispectral Index and BIS are registered trademarks of Aspect Medical Systems, Inc. All other trademarks, service marks and company names are the property of their respective owners.