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Spinal Surgery Research Papers

The following is a listing of research papers written by NDI's customers regarding Spinal Surgery.

Displaying results 1 to 4 of 4

TitleAbstractAuthor(s)
Computer-assisted fluoroscopic navigation of pedicle screw insertion: an in vivo feasibility study Accurate placement of pedicle screws is difficult. Patients and Methods: We evaluated the feasibility and accuracy of pedicle screw insertion assisted by a real-time, 2-dimensional (2D) image-guided navigation system in 12 patients who underwent thoraco-lumbar and/or lumbar stabilization. 66 pedicle screws were inserted either by senior spine surgeons or residents. The accuracy of positioning of the screws was evaluated using postoperative plain radiographs and thin-cut CT. Results: 61 of the 66 screws were inserted successfully. 5 screw insertions showed structural violations: 4 on the medial and 1 on the lateral pedicle wall. The accuracy was higher in the sagittal plane than in the axial plain. There was no difference between the surgical error rates caused by the senior surgeons and the residents. Interpretation: Using computer-assisted 2D fluoroscopic image navigation, it is possible to achieve reliable and accurate pedicle screw insertion during low thoracic and lumbar spinal surgery. ... [Expand] CB Wong, CC Niu, LH Chen, PL Lai, TS Fu, TT Tsai, WJ Chen
Image-guided spinal navigation: application to spinal metastases

Image-guided spinal navigation is an adjuvant surgical technology that has evolved over the past decade. It has been used as a replacement for conventional intraoperative imaging techniques to improve the spine surgeon's spatial orientation to nonvisualized anatomy. The author will review the principles of image-guided technology in spinal surgery and focus on its application to the management of spinal metastatic disease.

... [Expand] 		IH Kalfas
Surface-based registration accuracy of CT-based image-guided spine surgery

Registration is a critical and important process in maintaining the accuracy of CT-based image-guided surgery. The aim of this study was to evaluate the effects of the area of intraoperative data sampling and number of sampling points on the accuracy of surface-based registration in a CT-based spinal-navigation system, using an optical three-dimensional localizer. A cadaveric dry-bone phantom of the lumbar spine was used. To evaluate registration accuracy, three alumina ceramic balls were attached to the anterior and lateral aspects of the vertebral body. CT images of the phantom were obtained (1-mm slice thickness, at1-mm intervals) using a helical CT scanner. Twenty surface points were digitized from five zones defined on the basis of anatomical classification on the posterior aspects of the target vertebra. A total of 20 sets of sampling data were obtained. Evaluation of registration accuracy accounted for positional and rotational errors. Of the five zones, the area that was the largest and easiest to expose surgically and to digitize surface points was the lamina. The lamina was defined as standard zone. On this zone, the effect of the number of sampling points on the positional and rotational accuracy of registration was evaluated. And the effects of the additional area selected for intraoperative data sampling on the registration accuracy were evaluated. Using 20 surface points on the posterior side of the lamina, positional error was 0.96 mm +/- 0.24 mm root-mean-square (RMS) and rotational error was 0.91 degrees +/- 0.38 degrees RMS. The use of 20 surface points on the lamina usually allows surgeons to carry out sufficiently accurate registration to conduct computer-aided spine surgery. In the case of severe spondylosis, however, it might be difficult to digitize the surface points from the lamina, due to a hypertrophic facet joint or the deformity of the lamina and noisy sampling data. In such cases, registration accuracy can be improved by combining use of the 20 surface points on the lamina with surface points on other zones, such as on the both sides of the spinous process.

... [Expand] 		H Yoshikawa , K Yonenobu , N Sugano, S Tamura, T Ochi, T Sasama, Y Sato, Y Tamura
Technology Improvements for Image-guided and Minimally

This paper reports on technology developments aimed at improving the state of the art for
image-guided, minimally invasive spine procedures. Back pain is a major health problem with serious economic consequences. Minimally invasive procedures to treat back pain are rapidly growing in popularity due to improvements in technique and the substantially reduced trauma to the patient versus open spinal surgery. Image guidance is an enabling technology for minimally invasive procedures, but technical problems remain that may limit the wider applicability of these techniques.

The paper begins with a discussion of low back pain and the potential shortcomings of
open back surgery. The advantages of minimally invasive procedures are enumerated, followed by a list of technical problems that must be overcome to enable the more widespread dissemination of these techniques. The technical problems include improved intraoperative imaging, fusion of images from multiple modalities, the visualization of oblique paths, percutaneous spine tracking, mechanical instrument guidance, and software architectures for technology integration.

Technical developments to address some of these problems are discussed next. The
discussion includes intraoperative CT imaging, MR/CT image registration, 3D visualization, optical localization, and robotics for percutaneous instrument placement. Finally, the paper concludes by presenting several representative clinical applications: biopsy, vertebroplasty, nerve and facet blocks, and shunt placement.

The program presented here is a first step to developing the physician-assist systems of
the future, which will incorporate visualization, tracking, and robotics to enable the precision placement and manipulation of instruments with minimal trauma to the patient.

... [Expand] 		Fraser Henderson, Jianchao Zeng, Kevin Cleary, Mark Clifford, Matthew Freedman, Seong K. Mun, Vance Watson

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