Image-guidance has not been widely adopted in open lumbar fusion procedures because of cumbersome patient registration techniques. Accumulated mobility between vertebrae prohibits use of skin-affixed fiducials (requiring the surgeon to identify, expose, and localize anatomical landmarks within the surgical field), and registration at the start of surgery does not compensate for intervertebral motion between preoperative supine CT scans and intraoperative prone patient position. An automated registration procedure could accelerate adoption and improve outcomes, in addition to reducing costs, complexity, and x-ray dose associated with spine surgical guidance methods in current clinical use. Our target population is patients with symptomatic lumbar degenerative spondylolisthesis, where open decompression and fusion surgery, performed more than 300,000 times annually, improves patient-reported outcomes compared to non-surgical treatment. Image- guidance allows more accurate placement of pedicle screws, which could reduce revision rates and minimize patient harm, thereby allowing hospitals and surgeons to avoid reimbursement penalties from Medicare and other payers. We have developed an automated image-based intraoperative stereovision (iSV) to preoperative CT (pCT) registration that compensates for intervertebral motion, and have successfully applied the technique in two live animals, achieving excellent target registration errors (TREs less than 2.1 mm). We now propose to improve technical aspects of the approach in experimental studies and assess feasibility of this novel registration technology for clinical implementation. Specifically, we will (i) develop a portable iSV scanner as a radiation-free alternative to intraoperative CT (iCT) or O-arm, (ii) validate, evaluate and optimize the tehcnique in a systematic series of live animal surgeries, and (iii) translate the technology into a series of human cases of open lumbar fusion for degenerative spondylolisthesis. Comparisons of the new iSV approach to standard-of- care image-guidance with a commercial system (e.g., Medtronic StealthStation) and to high-fidelity navigation achieved with iCT will be performed to establish the relative performance improvements that can be obtained.

Public Health Relevance

Despite the effectiveness of image-guidance to improve accuracy and patient outcome in surgery, this technology has not been widely adopted in open spinal procedures primarily because of challenges in patient registration. We propose to develop intraoperative stereovision (iSV) to meet the demand and challenges specific to the spine to achieve accurate, efficient and robust patient registration in open spinal surgery. These efforts will ultimately accelerate the adoption of image guidance into spinal surgery to lower failure rates and improve patient postoperative function.

National Institute of Health (NIH)
National Institute of Biomedical Imaging and Bioengineering (NIBIB)
Research Project (R01)
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Special Emphasis Panel (ZRG1)
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Duan, Qi
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Dartmouth College
Engineering (All Types)
Biomed Engr/Col Engr/Engr Sta
United States
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Lollis, S Scott; Fan, Xiaoyao; Evans, Linton et al. (2018) Use of Stereovision for Intraoperative Coregistration of a Spinal Surgical Field: A Human Feasibility Study. Oper Neurosurg (Hagerstown) 14:29-35
Evans, Linton; Olson, Jonathan D; Cai, Yunliang et al. (2018) Stereovision Co-Registration in Image-Guided Spinal Surgery: Accuracy Assessment Using Explanted Porcine Spines. Oper Neurosurg (Hagerstown) 15:686-691