Siemens Scientists Develop 3-D Technology That Renders Patients Essentially ``Transparent'' for Surgical Procedures.

Business Editors and Health/Medical Writers

PRINCETON, N.J.--(BUSINESS WIRE)--April 23, 2002

The surgeon looks at the MR image on the monitor to check the location of a brain tumor that lies slightly less than seven centimeters beneath the patient's skull, in the right quadrant about half way down.

He marks the patient's head for the incision, looks at the monitor. checks the mark, checks the monitor again, then begins to cut.

During the thousands of surgical procedures performed each year, many surgeons -- regardless of their years of experience -- may well wish there were some means of seeing exactly where to make the incision. That day is quickly becoming a reality thanks to a Siemens technology that essentially renders the patient transparent to the surgeon.

Known as augmented reality image guidance, or in-situ visualization, the Siemens prototype employs a head-mounted display (HMD) that carries three miniature cameras. Two of the video cameras capture a stereoscopic view of the surgical site; the third camera is used for viewpoint tracking, in combination with optical markers framing the surgical site.

A computer superimposes 3-D computer images taken from the patient's own CT or MR data onto the video view for display on the surgeon's HMD. The surgeon, looking at the patient, can now perceive computer models of anatomical structures at the location of the actual structures. For example, a tumor visible on a medical image can now be seen at the location of the actual tumor.

"The ability to look inside the patient and see the tumor in three-dimensional space from different angles helps the surgeon determine the best route to the tumor," notes Frank Sauer, Ph.D., project manager in the Imaging and Visualization Department. "The dynamic viewpoint provides a very direct and intuitive understanding of even complex anatomy."

Sauer has been working with Gregory J. Rubino, M.D. of the University of California at Los Angeles School of Medicine for nearly one year. According to Dr. Rubino, who is investigating the new technology's clinical applications, "Augmented vision can support surgical planning in a very intuitive and efficient way."

The researchers are exploring in-situ visualization with a variety of medical imaging modalities, using computed tomography (CT), magnetic resonance (MR) and ultrasound imaging. To date, pre-clinical tests on phantom objects have been performed with encouraging results.

According to Dr. Sauer, "The basic technical problems have been solved, and a prototype could be ready to enter clinical testing and evaluation in approximately six months." He further noted that SCR is actively exploring clinical applications with Siemens Medical Solutions' CT, MR, Ultrasound and X-ray divisions.

About Siemens Corporate Research

Siemens Corporate Research, Inc. (SCR), is associated with Siemens AG's Corporate Technology (CT) organization, and is one of five CT R&D centers worldwide. First established in the U.S. in 1977, and now based in the Princeton Forrestal Center, SCR is staffed by approximately 200 research and support professionals.

SCR has global responsibility for four core technology areas: imaging and visualization, software engineering, multimedia/video technology, and multimedia documentation. Business Development, a corporate program, identifies emerging technologies in health care and other market sectors. Siemens

Technology-To-Business Center LLC, an SCR subsidiary located in Berkeley, Calif., converts innovative technologies into viable new Siemens businesses or independent, start-up companies. For more information, visit SCR's web site at: www.scr.siemens.com or TTB's web site at www.ttb.siemens.com.

Siemens AG (NYSE:SI), headquartered in Munich, is a leading global electronics and engineering company. It employs more than 450,000 people in 193 countries, and reported worldwide sales of $74 billion in fiscal 2001 (10/1/00 - 9/30/01). The United States is Siemens' largest market, with nearly 80,000 employees and sales of $18.9 billion for fiscal 2001. For more information about Siemens in the U.S., go to www.usa.siemens.com.

Note to Editors: A picture of Dr. Sauer using a prototype head mounted display to simulate how surgeons, using augmented visualization, will be able to see a brain tumor inside a patient's head, is available for downloading at two sites: www.scr.siemens.com (press gallery) and www.siemens-news.com (media gallery).