ON TARGET Graduate student Ali Uneri demonstrates the new surgical guidance system, which uses images from a mobile C-arm.

A new surgical navigation system that uses images from an ordinary mobile C-arm provides more accurate results and more efficient operation than current state-of-the-art image-guidance systems, say researchers. The innovative computerized orientation process could improve precision and patient safety in a wide range of minimally invasive procedures, particularly spine surgery and neurosurgery, write the Johns Hopkins University engineers in a recent issue of the journal Physics in Medicine and Biology.

Setting up a conventional image-guidance system for use during surgery necessitates a laborious process known as registration, the correspondence of points on a patient's body to those appearing in a pre-op CT image that lets the system orient its images.

"The registration process can be error-prone, require multiple manual attempts to achieve high accuracy and tends to degrade over the course of the operation," says Jeffrey Siewerdsen, PhD, a professor of biomedical engineering at Johns Hopkins.

The new system, using an algorithm that the research team had previously constructed to help spine surgeons navigate vertebral levels, automatically matches 2D fluoroscopic images to 3D CT scans and updates them throughout the case.

"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," says Dr. Siewerdsen.

Testing the system on cadavers, the team has found that its results are consistently more precise than those of existing systems, delivering better than 2mm of accuracy as compared to a standard of 2mm to 4mm. They're currently working to translate their methods into a system that can be studied by a wider clinical audience.

"The breakthrough came when we discovered how much geometric information could be extracted from just one or two X-ray images of the patient," says computer science graduate student Ali Uneri. "From just a single frame, we achieved better than 3 millimeters of accuracy, and with 2 frames acquired with a small angular separation, we could provide surgical navigation more accurately than a conventional tracker."

Better still: the system can derive this navigational information from images taken with an extremely low dose of radiation, exposing the patient to even less radiation than a routine intraoperative image would.

— David Bernard

Soak Away Surgical Instrument Stains
A 15-minute soak in Surgistain can remove rust, stains, spotting, hard water scale and mineral deposits from stainless steel surgical instruments, trays and basins, says Ruhof Healthcare. The mildly acidic revitalizing solution can also help to loosen stiff joints and locks, restoring functionality to increase instrument lifespans. The company promotes its safety for use on delicate instruments, including ophthalmic devices, as well as on endoscope and microscope accessories.
ruhof.com

Vacuum Clipped Hair
Your staff won't have to worry about cleaning up clippings after they remove hair from the surgical site. In or out of the OR, in wet or dry conditions, you can connect the ClipVac from Surgical Site Solutions to CareFusion's new surgical clippers to vacuum hair clippings as you cut the hair at the source, thus reducing the need for a secondary clean up.
carefusion.com

A Convenient Kit for CHG Skin Cleanses
This kit from Clorox Healthcare makes it easy for patients to follow your protocols for chlorhexidine gluconate (CHG) skin cleansing to reduce bacteria on the skin before surgery. Patients will find everything they need for 2 pre-procedural CHG showers inside Aplicare's 2-in-1 CHG Skin Cleansing Kit. Each pack includes: a 4 oz. bottle of 4% CHG solution, 3 disposable washcloths and waterproof instructions that patients can bring into the shower.
aplicarecleansingkit.com