PRESS RELEASE Stockholm, Sweden, August 14, 2007 The highly respected Barnes-Jewish Hospital has placed an order for Leksell Gamma Knife® Perfexion™, the most advanced system for non-invasive radiosurgery in the world.

Leksell Gamma Knife Perfexion is a revolutionary alternative to traditional open-brain surgery and daily radiation treatments, using focused doses of radiation without making a single incision to treat malignant and benign brain tumors, as well as, other brain disorders.

Performing Gamma Knife radiosurgery since 1998, the Gamma Knife center at Barnes-Jewish Hospital offers stereotactic radiosurgery for patients in the St. Louis-Metropolitan area, the surrounding Midwest region, as well as, patients from more distant locations.

"For more than nine years, the Gamma Knife of St. Louis has provided greater options in treating patients with brain tumors, as well as, other intracranial structures,” says Keith M. Rich, M.D., co-director of the Gamma Knife of St. Louis at Barnes-Jewish Hospital. “We’re looking forward to the greater capabilities the Leksell Gamma Knife Perfexion unit will provide in the near future."

Gamma Knife surgery has become the world’s most widely used radiosurgery treatment due to its extraordinary accuracy, reduction of excess radiation dose to the body, extensive history and clinical documentation. Unlike other systems designed to treat the whole body, Leksell Gamma Knife specifically is designed to optimize treatment to the head – a fact appreciated by neurosurgeons and patients alike.

Building a Better Treatment System

Developed in conjunction with leading neurosurgeons, Leksell Gamma Knife Perfexion is:

• Precise – thousands of radiation beams converge with a level of accuracy more than 0.5 mm, about the thickness of a strand of hair, leaving nearby healthy tissue undamaged.

• Proven – With almost 500,000 patients treated worldwide, and thousands of peer-reviewed scientific articles, the system has unmatched clinical experience.

• Safe – Unwanted radiation dose to the body is up to 100 times less than that of competing technologies.