Doing more, with less - isn't that what we hear about all the time in healthcare? Well, what about doing more, with more. That is what image-guided surgery technology is allowing surgeons to do. The powerful navigation systems and tools are expanding the possibility of preoperative and intraoperative image guidance, all of which are performed less invasively. And it's not just cranial surgery for which IGS is standard of care, applications in ENT surgery are maturing and orthopedic trauma and spinal surgeons are adopting the technology as well.
Image-guided surgery (IGS) enables surgeons to perform complex, minimally invasive surgery (MIS). IGS technology combines high-speed computers, specialized software and tracking techniques so that surgeons can view three dimensional (3D) images of body organs and their relation to surgical instruments. Precision increases twofold and surgeons can more accurately and safely access anatomy through natural body openings or smaller surgical incisions so that patients experience less trauma, shorter hospital stays and reduced pain.
Prior to IGS, a surgeons' field of view was limited to the end of an endoscope when performing MIS. A bit of estimation was needed to correlate the patient's preoperative medical images with the operative field. Image-guidance technology, on the other hand, automatically correlates a patient's electronic images with the movements of surgical instruments and displays this on a monitor in the operating room.
For preoperative image guidance, a patient typically undergoes a CT or MR scan prior to surgery. The images, used by the surgeons to map out their surgical pathways, also are imported into the IGS software right before surgery to register the patient's physical anatomy to the computer scan information. Surgeons can then track in real-time their progress on the IGS monitor.
Neurosurgeons use image guidance to locate intracranial lesions for resection or biopsy. "The benefits are that you can plan the craniotomy with a knowledge of exactly what you are going to see beneath the surface," says Alexandra Golby, MD,
associate surgeon, Brigham & Women's Hospital, Neurosurgery Department, and instructor at Harvard Medical School. "This allows us to make smaller craniotomies, more precise craniotomies, it allows us to attack the tumor more directly and have the patients leave the hospital faster with less recovery time."
The 10-year-old technology has come a long way. "[IGS] used to be a whole different ballgame," says Golby. "It used to be line-of-sight dependent and the receiver used to be on a separate boom in the room. Now we have the ability to co-register various scans, we can fuse CTs to MRIs, we can incorporate functional data, we can use the system to place stunts and place biopsies."
PUSHING THE ENVELOPE
Neurosurgeons need to know at the time of surgery precisely the intricate details of brain anatomy and function as well as the relation of the surgical site to normal structures. Multimodality images such as CT, MRI, SPECT and PET - along with budding technologies such as spectroscopy, diffusion tensor imaging and functional MRI - help neurosurgeons better identify this information. Image guidance will allow surgeons to bring this rich data into the OR and navigate with it, says Warren Boling, MD, assistant professor of neurosurgery at West Virginia University Medical Center (WVU).
Applying the science of imaging to the art of surgery is part of a collaboration WVU has with IGS vendor BrainLAB Inc. of Munich, Germany. Researchers at WVU's Center for Advanced Imaging use BrainLAB's VectorVision IGS technology to improve the process of identifying subtle lesions on the brain and navigating around the brain in an effort to make neurosurgery safer, says Boling. WVU researchers want to develop new IGS applications such as tracing the fiber tracks of the brain, integrating functional MRI into image guidance and integrating an ultrasound device into image guidance.
The backbone to this is WVU's substantial investment in a robust IT infrastructure for the hospital's new surgical suite. By integrating BrainLAB with radiology's PACS, electronic medical images will literally be at the fingertips of surgeons prior to and during surgery. "Our goal is to directly bring imaging into the OR and have the ability to upload electronic medical images [from the hospital's filmless radiology department] into image guidance directly through a wire," forsees Boling. "Right