Even if we are working on an emergency case at midnight, we can use OsiriX on a Mac to view the 3D volumes from multi-detector CT slices. We don't need to wait for a radiologist to show us these images any more.
Maki Sugimoto, MD, PhD
25/10 to 28/10, HUG. Geneva.
Creating Roadmaps for Surgeons
Using the Mac for Better Surgical Navigation
A woman in her forties lies anesthetized on an operating table. The surgical team prepares her torso for surgery, and switches on an overhead projector. A three-dimensional image of the patient’s internal organs appears on the surface of her abdomen and is aligned with her body. The image changes as Dr. Maki Sugimoto, using a wireless remote to control a Mac Pro workstation, navigates through the 3D volume to bring up the surgical target –early stage gastric cancer. Guided by the display, the team makes precise incisions to insert ports for laparoscopic surgery.
The same 3D images of the patient’s anatomy appear on a 23-inch Apple Cinema Display beside the surgical table. Sugimoto uses the remote to move and rotate images for a better view of the cancerous tissue. He inserts the laparoscope into a port and navigates to the surgery site, guided by the monitor of the scope and the reference images on the Apple Cinema Display.
In many operating rooms, this cancer would have been treated with aggressive open surgery. But in this case 3D visualization has enabled efficient, minimally invasive surgery and a better outcome for the patient.
Wanted: A Better Surgical Road Map
Sugimoto, an assistant professor at the 520-bed Teikyo University Chiba Medical Center near Tokyo, has been using Macs since his college days. Today he uses them to plan and conduct both minimally invasive and aggressive open surgery.
After Sugimoto completed his residency as an M.D. and secured a PhD in medical science at the Teikyo Graduate School of Medicine, he was appointed Assistant Professor at Teikyo University Chiba Medical Center. He was looking for ways to use imaging technology to improve surgical procedures.
“When you’re driving into new territory, you want a map, or better still a navigation system,” says Sugimoto. “We wanted to improve surgical accuracy and efficiency with image-guided navigation. We wanted all the surgeons on the surgical team to see the same visual data, the same images, so we can make informed decisions jointly.”
Sugimoto was browsing the Apple Web site in 2004 when he came across OsiriX, a Mac-based open-source software system for viewing DICOM-format radiological images. He downloaded OsiriX and began experimenting. He had found the navigation aid he needed.
Sugimoto began building his own surgical roadmaps. Today the Center’s radiology department takes CT scans of his patients, and sends him the DICOM files. He runs OsiriX on a Mac Pro or a MacBook Pro to segment them into volumetric 3D images that he uses to plan and perform surgery.
“OsiriX is easy,” says Sugimoto. “We learned it without formal training because its interface is similar to other Mac applications. Now we have a Japanese user interface for OsiriX, which makes it even easier for us. Students and residents can use it easily. And we can do the segmentation on our personal desktops or laptops anytime. This is important: even if we’re working on an emergency case at midnight, we can use OsiriX on a Mac to view the 3D volumes from multi-detector CT slices. We don’t need to wait for a radiologist to show us these images anymore.”
Minimally Invasive Surgery: Putting the Road Map on the Patient
For patients with early-stage gastric or colonic cancer, the surgical team typically opts for minimally invasive laparoscopic surgery. With the patient anesthetized, Sugimoto projects OsiriX-generated 3D images onto the body surface of the patient with an Epson EMP-1715 projector. Using a motion-sensing wireless remote, Sugimoto uses physiological markers (such as the navel) to register the image to the patient’s body. Then using a Color Look Up Table (CLUT) feature in OsiriX, he makes the skin of the image transparent. The display now shows the patient’s internal body parts and the area that he will need to operate on.
“It’s hard to detect the location of very small cancers laparoscopically,” says Sugimoto. “But when we project on the patient’s body, we can see the exact location of even a very small cancer using multi-detector CT reconstruction. That helps us to pinpoint the insertion of the ports and accomplish three things: avoiding injury to organs when we make the insertions; strategically placing the ports for efficient navigation with the scope; and keeping the number of ports to a minimum. All this adds up to minimally invasive surgery.”
With the ports in place and the scope inserted near the cancer site, Sugimoto aims the remote at the Apple Cinema Display and, with a flick of the wrist, he rotates the image of a section of colon to study the lesions. After a 360-degree examination on OsiriX using the Mac Pro, he proceeds with the operation. For some procedures, Sugimoto connects the remote to the laparoscope, so that the image on the scope monitor and the 3D image on the Apple Cinema Display move in concert.
“It’s common for surgeons operating on these cancers to use aggressive open surgery, making a midline incision to open the stomach,” says Sugimoto. “But our technique gives patients a better chance for faster recovery.”
Visualization for Major Open Surgery
For major gastrointestinal surgeries, particularly in the team’s sub-specialty of hepatic/biliary/pancreatic (HBP) surgery, Sugimoto uses the Mac and OsiriX in a different way.
“When we perform aggressive surgeries such as those for pancreatic cancer, many organs, blood vessels, and lymph nodes need to be removed,” says Sugimoto. “If the cancer has invaded the vascular system, we have to determine its surgical margin to complete the resection and vascular reconstruction. Pre-operative volume visualization helps us to be more efficient in the operating room.”
Sugimoto uses real-time 3D volume rendering with OsiriX as a reference during open surgery, manipulating images on the Apple Cinema Display to get a more explicit view of surgical targets.
“The 3D visualization shows us relationships between the cancer and the arterial vessels and other surrounding organs,” says Sugimoto. “It also allows us to see the extent of the spread of cancer. When a patient has upper biliary (bile duct) cancer, we have to cut the liver. If the patient has lower bile duct cancer we have to remove the pancreatic head and duodenum. The HBP system is very complex; that’s why 3D visualization in the OR is so crucial. When doing a midline open surgery, the surgeon can only see the organs from the top. With OsiriX on the Mac, surgeons can rotate and see the surrounding organs in 3D to guide them during surgery.”
An Easily Adoptable Technology
Sugimoto and his team do about 50 major surgeries a month using his 3D visualization techniques. Of these, Sugimoto does about 20 himself. Major surgeries, such as pancreatic cancer surgery involving the vascular system, may take up to six hours; minor surgeries – laparoscopic cholecystectomies – take about an hour. The surgery group uses a variety of Macs to run OsiriX for processing DICOM images and planning surgeries. They record videos of all laparoscopic surgeries, and of some open surgeries, for educational purposes. Sugimoto uses iMovie 08 and Final Cut Express, both of which he finds simple and easy to use, to edit movies himself.
Sugimoto is modest about his innovations with the Mac.
“Many surgeons react with surprise when they first see these techniques demonstrated. But surgeons and physicians familiar with OsiriX see them as practical and easy to implement. They know it’s easy to work with OsiriX volumetric images, and that OsiriX handles segmentation and 3D rendering of DICOM images with ease. And they can see the value that visualization can have in the OR.”
Sugimoto has given presentations at many Japanese and international institutions explaining his techniques. Each presentation is usually followed by requests to give it elsewhere, including the United States. In Japan a number of surgeons and physicians have seen the presentation, purchased Macs, downloaded OsiriX, and started using his visualization methods in surgery and daily clinics.
“These techniques are very easy for surgeons and physicians to adopt,” says Sugimoto. “After all, I did it.”
The bottom line here is that Sugimoto’s innovative use of OsiriX and the Mac has improved the level of care for his team’s surgical patients. Using visualization to plan surgeries, to navigate to surgical sites, and identify even minute lesions – as well as implementing minimally invasive techniques where they are not commonly used – helps assure that patients will experience the best possible outcomes.
