Diffuse reflectance spectroscopy accurately identifies the pre-cortical zone to avoid impending pedicle screw breach in spinal fixation surgery

Diffuse reflectance spectroscopy accurately identifies the pre-cortical zone to avoid impending pedicle screw breach in spinal fixation surgery

Burström, Gustav (Karolinska Institutet; Karolinska University Hospital)
Swamy, A. (TU Delft Medical Instruments & Bio-Inspired Technology; Philips Research)
Spliethoff, Jarich W. (Philips Research)
Reich, Christian (Philips Research)
Babic, Drazenko (Philips Research)
Hendriks, B.H.W. (TU Delft Medical Instruments & Bio-Inspired Technology; Philips Research)
Skulason, Halldor (Landspitali University Hospital)
Persson, Oscar (Karolinska Institutet; Karolinska University Hospital)
Terander, Adrian Elmi (Karolinska Institutet; Karolinska University Hospital)
Edström, Erik (Karolinska Institutet; Karolinska University Hospital)

2019

Pedicle screw placement accuracy during spinal fixation surgery varies greatly and severe misplacement has been reported in 1-6.5 % of screws. Diffuse reflectance (DR) spectroscopy has previously been shown to reliably discriminate between tissues in the human body. We postulate that it could be used to discriminate between cancellous and cortical bone. Therefore, the purpose of this study is to validate DR spectroscopy as a warning system to detect impending pedicle screw breach in a cadaveric surgical setting using typical clinical breach scenarios. DR spectroscopy was incorporated at the tip of an integrated pedicle screw and screw driver used for tissue probing during pedicle screw insertions on six cadavers. Measurements were collected in the wavelength range of 400-1600 nm and each insertion was planned to result in a breach. Measurements were labelled as cancellous, cortical or representing a pre-cortical zone (PCZ) in between, based on information from cone beam computed tomographies at corresponding positions. In addition, DR spectroscopy data was recorded after breach. Four typical pedicle breach types were performed, and a total of 45 pedicle breaches were recorded. For each breach direction, the technology was able to detect the transition of the screw tip from the cancellous bone to the PCZ (P < 0.001), to cortical bone (P < 0.001), and to a subsequent breach (P < 0.001). Using support vector machine (SVM) classification, breach could reliably be detected with a sensitivity of 98.3 % [94.3-100 %] and a specificity of 97.7 % [91.0-100 %]. We conclude that DR spectroscopy reliably identifies the area of transition from cancellous to cortical bone in typical breach scenarios and can warn the surgeon of impending pedicle breach, thereby resulting in safer spinal fixation surgeries.

http://resolver.tudelft.nl/uuid:a645834c-d606-47b1-b793-372856239821

https://doi.org/10.1364/BOE.10.005905

2156-7085

Biomedical Optics Express, 10 (11), 5905-5920

Institutional Repository

journal article

© 2019 Gustav Burström, A. Swamy, Jarich W. Spliethoff, Christian Reich, Drazenko Babic, B.H.W. Hendriks, Halldor Skulason, Oscar Persson, Adrian Elmi Terander, Erik Edström