The machine in action. The O-arm and StealthStation navigation
system form a mobile surgical imaging platform

O-Arm Surgical Imaging System

Sunnybrook Research Institute (SRI) has acquired a Medtronic O-arm and StealthStation surgical navigation system to develop minimally invasive procedures for musculoskeletal surgical applications. Together, they form a mobile surgical imaging platform for use in spine, orthopaedic and trauma-related surgeries.

"The O-arm, used in combination with the Stealth navigation system, allows us to navigate surgeries in real time based on intraoperative, conebeam CT [computed tomography] scans," says Dr. Cari Whyne, director of the Holland Bone and Joint Research Program at SRI.

The O-arm's donut-shaped CT scanner gantry (a movable frame that contains the X-ray tube and detectors) allows for simple, low-radiation, 2-D fluoroscopic images or full 3-D reconstructions in standard and high-definition resolution. The system's digital flat-panel detector provides a large field of view, resulting in precise images of a patient's skeletal anatomy.

The system, worth $1.6 million, is part of the preclinical testing facility within SRI's Centre for Research in Image-Guided Therapeutics. Whyne will use the equipment in her research on photodynamic therapy for cancer that has spread to the spine. The therapy combines a light-sensitive drug with a locally applied light delivered via a laser fibre inside a small tube called a cannula. When the drug is taken up in the tumour and a light from the laser is turned on, the cancerous cells die.

"The O-arm allows us to visualize exactly where that cannula is placed, so we can ensure optimal treatment delivery intraoperatively," says Whyne.

Currently located in the hospital's musculoskeletal operating room on the second floor of M wing, the system will eventually be housed in the preclinical testing facility in S wing, set for completion next spring.

The purchase of the O-arm surgical imaging system was made possible by a $57-million infrastructure grant from the Canada Foundation for Innovation through its Research Hospital Fund.