gms | German Medical Science

Objective: Spinal Navigation is gradually becoming a standard for spinal instrumentations and hereby improving the accuracy of pedicle screw insertion to over 95%.Spinal tumor resections, be it bony, extraduralorintradural lesions,are often performedsolelywith intraoperative fluoroscopic guidance. An intraoperative image aided visualizationof the tumorsis seldom appliedthus frequently leading to semi-estimated approaches.Aim of this study was tospecificallycustomizethe surgical approachesforintraspinallesions by fusing preoperative spinal magnetic resonance imaging (MRI)with intraoperatively conducted navigationaldata from a robotic C-arm Dyna-CT.

Methods: All patients were positioned to standard as for fluoroscopic aided approaches. This wasfollowed byafluoroscopicassessment of treatment levels.A virtualskinincision wasplanned under fluoroscopic guidance as comparative reference. Aminute skinincision was then performed to fixate reference arrayto thespinous process. 3D navigation datafrom arobotic C-arm Dyna-CTwasacquired,autoregistratedandmergedwithpreoperativevolumetric spinal MRI images. After completion ofanMRI navigated approachanintraoperative ultrasound was performed for intradural lesion to verifythe navigationalaccuracybeforeopeningofthe dura.

Results: From January 2017 11 patients with spinal tumors underwentMRI navigated surgical resection at our department. Four of which had neurinomas, 2 hadmeningeomasand 5 hadintraspinalextraduralmetastasis. Surgical times weremerelyextendedby 12minutesinmean.Skin incision sizes weresignificantlyreduced by 23% leading to a consecutive reductionof thesubcutaneousapproachdimensions. Wrong level surgery did not occur in any of the cases.

Conclusion: Analog to navigated cranial surgery, image guided resection of spinal tumorsseemsto bebeneficial.This methodsecurely allowsa lesioncustomizedapproach with significant reduction of approach dimensions thusleading a decrease in peri- and postoperative morbidity. Wrong level surgery with excessive boneremovalcouldbe avoided.Further analysisisneeded toassessa radiation exposureand apotentialdecreaseof bloodloss incomparison totheseeminglylargerfluoroscopic guided approaches.