title: Intraoperative sonography of intra- and extramedullary tumors.
abstract: Intraoperative ultrasound (IOUS) was used in planning the operative resection of intradural spinal tumors, to define its diagnostic potential and limitations. Since 1997, 78 patients diagnosed with an ependymoma (n = 24), astrocytoma (n = 7), hemangioblastoma (n = 7), neurinoma (n = 15), meningioma (n = 17) and filum terminale ependymoma (n = 8) were examined using intraoperative transdural sonography. Intramedullary tumors turned out to show a heterogeneous image with occasional cystic alterations and an indistinct demarcation to the myelon of comparable echogenicity. Intramedullary tumors are easily distinguishable from their extramedullary counterparts, which display a homogeneous signal intensity and sharp demarcation on IOUS. In conclusion, IOUS allows a reliable diagnosis of intraspinal tumors, allowing the distinction between intra- and extramedullary tumors through their respective signal characteristics. Using IOUS, the extension of the neurosurgical approach can be adopted to the true extent of the tumor; thus, avoiding further bone work while the dura is already opened and the frequently edematous spinal cord protrudes through the opening. Our experiences have shown that IOUS may reduce the procedure-related morbidity and should, therefore, be used as a standard intraoperative tool in these high-risk surgical entities. (E-mail: ).
authors.affiliation: Department of Neurosurgery, University Hospital of Hamburg, Martinistrasse 52, 20246 Hamburg, Germany. j.regelsberger@uke.uni-hamburg.de
authors.forename: Jan
authors.initials: J
authors.lastname: Regelsberger
authors.forename: Erik
authors.initials: E
authors.lastname: Fritzsche
authors.forename: Niels
authors.initials: N
authors.lastname: Langer
authors.forename: Manfred
authors.initials: M
authors.lastname: Westphal
mesh_terms: D001132:Arm / Q000503:physiopathology; D001254:Astrocytoma / Q000000981:diagnostic imaging / Q000601:surgery; D004806:Ependymoma / Q000000981:diagnostic imaging / Q000601:surgery; D018325:Hemangioblastoma / Q000000981:diagnostic imaging / Q000601:surgery; D006801:Humans; D007432:Intraoperative Period; D007866:Leg / Q000503:physiopathology; D008279:Magnetic Resonance Imaging / Q000379:methods; D008579:Meningioma / Q000000981:diagnostic imaging / Q000601:surgery; D009442:Neurilemmoma / Q000000981:diagnostic imaging / Q000601:surgery; D011183:Postoperative Complications / Q000517:prevention & control; D013120:Spinal Cord Neoplasms / Q000000981:diagnostic imaging* / Q000601:surgery; D016896:Treatment Outcome; D014463:Ultrasonography