Johns Hopkins University researchers have developed a new imaging-based guidance system that could make minimally invasive surgery more accurate and streamlined.
According to the researchers, the system is potentially superior to conventional tracking systems that have been used by surgeons over the last decade.
"Imaging in the operating room opens new possibilities for patient safety and high-precision surgical guidance," Jeffrey Siewerdsen, a professor of biomedical engineering in the Johns Hopkins University School of Medicine, said in an announcement. "In this work, we devised an imaging method that could overcome traditional barriers in precision and workflow. Rather than adding complicated tracking systems and special markers to the already busy surgical scene, we realized a method in which the imaging system is the tracker and the patient is the marker."
Siewerdsen called the current system cumbersome, pointing out that it is reliant on someone manually matching points on a patient's body with pre-operative imaging. That process--called registration--"can be error-prone, require multiple manual attempts to achieve high accuracy and tends to degrade over the course of the operation," he said.
For the new system, the researchers adapted a mathematical algorithm previously developed to help surgeons locate vertebrae during spinal surgery for use in surgical navigation. They believed that a new, fast, accurate algorithm could match 2-D X-ray images to 3-D pre-operative CT scans automatically and stay up to date throughout an operative.
When tested, the alternative registration method--which requires the use of a mobile C-arm (already in use in most surgeries)--was found to be consistently more accurate than a conventional surgical tracker. Those results were published recently in the journal Physics in Medicine and Biology.
According to the researchers, not only is the new system more accurate, but it has the additional advantage of being able to acquire clinically-useful X-ray images at extremely low doses of radiation.
Siewerdsen said he believes the new system could be particularly useful in procedures such as spinal and intracranial neurosurgery.