title: X-ray scalpel - a new device for targeted x-ray brachytherapy and stereotactic radiosurgery.
abstract: The basic design and performance of a novel x-ray scalpel device for interstitial radiosurgery are reported. The x-ray scalpel is comprised of a capillary optics collimator conjugated with a high brilliance microfocus x-ray tube and a thin hollow needle (tip) attached to the collimator. The device is capable of producing a high dose rate (about 140 Gy min(-1) in water-like absorber at the exit window), 0.7 mm diameter, quasi-parallel beam that can be delivered to a targeted site by a minimally invasive procedure. Contrary to insertable x-ray tubes or radionuclides used in brachytherapy and complying with the 1/r(2) radiation attenuation law, the dose rate for a quasi-parallel beam decreases with distance as mu exp(-mu r), where mu is the energy-dependent linear attenuation coefficient in the exposed medium. Moreover, the shape, energy and the dose attenuation curve of the x-ray beam can be adjusted. Two versions of the x-ray scalpel device (5.4 keV and 20.2 keV) are described. We present results from our first test of the x-ray scalpel as a controllable source of focal radiation for producing radiation necrosis in rat brain tissue. Irradiation was transdurally delivered to the rat cerebral cortex for 10 min at a dose rate of 20 Gy min(-1).
authors.affiliation: Advanced X-Ray Technology, Inc., 1025 E. Maple Road, Birmingham, MI 48009, USA.
authors.forename: George
authors.initials: G
authors.lastname: Gutman
authors.forename: Emil
authors.initials: E
authors.lastname: Strumban
authors.forename: Evgeny
authors.initials: E
authors.lastname: Sozontov
authors.forename: Kenneth
authors.initials: K
authors.lastname: Jenrow
mesh_terms: D000818:Animals; D001918:Brachytherapy / Q000295:instrumentation* / Q000379:methods*; D002540:Cerebral Cortex / Q000000981:diagnostic imaging* / Q000473:pathology; D004867:Equipment Design; D006801:Humans; D009336:Necrosis; D019047:Phantoms, Imaging; D011859:Radiography; D016634:Radiosurgery / Q000295:instrumentation* / Q000379:methods*; D011879:Radiotherapy Dosage; D051381:Rats; D013819:Thermoluminescent Dosimetry / Q000379:methods*; D014965:X-Rays