title: Three-dimensional ultrasonography navigation in spinal cord tumor surgery. Technical note.
abstract: The authors describe the technical application of three-dimensional (3D) ultrasonography navigation in spinal cord tumor surgery. The spinal cord is a complex neurological structure in which there is the potential for causing neurological morbidity during tumor resection. Standard neuronavigation systems based on computed tomography or C-arm images are not adapted to tumor surgery in the spinal cord. Since 2004 the authors have been using a 3D ultrasonography-based neuronavigation system. During surgery, two-dimensional ultrasound images were acquired and reconstructed into 3D image data to assist in tumor resection. The navigation cameras read the position of a patient reference frame attached to a spinous process, the ultrasonography probe, and surgical instruments. Five- and 10-MHz phased-array ultrasonography probes equipped with optical tracking frames were used for image data acquisition. Spinal cord tumors were visualized using ultrasonography, and 3D ultrasonography-guided tumor biopsy sampling and resection were performed. The practice of attaching the reference frame to a spinous process adjacent to the spinal cord tumor, as well as performing image acquisition just before starting the resection, reduced the possible sources of inaccuracy. The technical application of a navigation system based on intraoperative 3D ultrasound image reconstruction seems feasible and may have the potential of improving functional outcome in association with spinal cord tumor surgery.
authors.affiliation: National Center of Spinal Disorders, National Center for 3D Ultrasound in Surgery, and Department of Neurosurgery, St. Olav University Hospital, Norway. Frode.Kolstad@ntnu.no
authors.forename: Frode
authors.initials: F
authors.lastname: Kolstad
authors.forename: Ola M
authors.initials: OM
authors.lastname: Rygh
authors.forename: Tormod
authors.initials: T
authors.lastname: Selbekk
authors.forename: Geirmund
authors.initials: G
authors.lastname: Unsgaard
authors.forename: Oystein P
authors.initials: OP
authors.lastname: Nygaard
mesh_terms: D000328:Adult; D000369:Aged, 80 and over; D002574:Cervical Vertebrae; D005260:Female; D005910:Glioma / Q000000981:diagnostic imaging / Q000601:surgery*; D020786:Hemangioma, Cavernous, Central Nervous System / Q000000981:diagnostic imaging / Q000601:surgery*; D006801:Humans; D021621:Imaging, Three-Dimensional; D008297:Male; D008875:Middle Aged; D038361:Neuronavigation / Q000379:methods*; D013120:Spinal Cord Neoplasms / Q000000981:diagnostic imaging / Q000601:surgery*; D013904:Thoracic Vertebrae; D014463:Ultrasonography