gms | German Medical Science

48th Meeting of the Particle Therapy Co-Operative Group

Particle Therapy Co-Operative Group (PTCOG)

28.09. - 03.10.2009, Heidelberg

Proton radiosurgery of intracranial arteriovenous malformations: Dubna experience

Meeting Abstract

  • M. Tseytlina - Proton Radiation Therapy and Radiosurgery Center, Joint Institute for Nuclear Research, Dubna, Russian Federation
  • Y. I. Luchin - Proton Radiation Therapy and Radiosurgery Center, Joint Institute for Nuclear Research, Dubna, Russian Federation
  • A. V. Agapov - Proton Radiation Therapy and Radiosurgery Center, Joint Institute for Nuclear Research, Dubna, Russian Federation
  • V. N. Gaevsky - Proton Radiation Therapy and Radiosurgery Center, Joint Institute for Nuclear Research, Dubna, Russian Federation
  • I. A. Gulidov - Proton Radiation Therapy and Radiosurgery Center, Joint Institute for Nuclear Research, Dubna, Russian Federation
  • A. G. Molokanov - Proton Radiation Therapy and Radiosurgery Center, Joint Institute for Nuclear Research, Dubna, Russian Federation
  • G. Mytsin - Proton Radiation Therapy and Radiosurgery Center, Joint Institute for Nuclear Research, Dubna, Russian Federation
  • K. Shipulin - Proton Radiation Therapy and Radiosurgery Center, Joint Institute for Nuclear Research, Dubna, Russian Federation
  • S. V. Shvidkij - Proton Radiation Therapy and Radiosurgery Center, Joint Institute for Nuclear Research, Dubna, Russian Federation

PTCOG 48. Meeting of the Particle Therapy Co-Operative Group. Heidelberg, 28.09.-03.10.2009. Düsseldorf: German Medical Science GMS Publishing House; 2009. Doc09ptcog209

DOI: 10.3205/09ptcog209, URN: urn:nbn:de:0183-09ptcog2091

Veröffentlicht: 24. September 2009

© 2009 Tseytlina et al.
Dieser Artikel ist ein Open Access-Artikel und steht unter den Creative Commons Lizenzbedingungen (http://creativecommons.org/licenses/by-nc-nd/3.0/deed.de). Er darf vervielfältigt, verbreitet und öffentlich zugänglich gemacht werden, vorausgesetzt dass Autor und Quelle genannt werden.


Gliederung

Text

Technique: Proton procedure room is equipped with horizontal beam line with particles energy of 155 MeV. Depth penetration in water is 160 mm. Beam has maximum size of 8x8cm. Several ridge filters with spread-out Bragg-peak region from 2 to 5 cm can be used for beam modulation. Patient positioner represents the treatment chair with 4 degrees of movement freedom. Patient's head is immobilized by the perforated thermoplastic mask. System for target alignment and beam centration includes orthogonal laser beams and X-ray tube for introscopic alignment. After mask manufacturing, treatment planning CT and MRI with up to 200 1–2 mm slices have been performed. Physician outlines target, critical structures, and alignment bone landmarks. Three-seven treatment beams are calculated. Beam forming devices include individual shape by cerrobend aperture, complex shape boluses. Digital reconstructed radiographs with projection of target, isocenter, coordinate axes and bone landmarks were calculated and printed. Alignment X-ray films were compared with DRRs during irradiation sessions. Alignment accuracy was in the range of 1 mm.

Material: Since Dec of 2001 till Feb 2009, 55 patients with cerebral AVM had been treated by proton radiosurgery in Dubna. We accepted international protocol for the dosimetry planning and absorbed dose selection, developed primarily at the Loma Linda University Medical Center by Dr. Schulte and Dr. Levy. Isocenter dose for small and medium size AVM was 25 GyE at 2 consecutive day fractions and for larger AVM 22.5 GyE. Target volume included mainly to 80% isodose line – 18–20 GyE. Volume of treated AVM varied from 1 to 82 cm3: 1-5 cc – 13; 5-25cc – 34; >25 cc – 8 patients.

Results: Follow-up assessment of AVM patients involved MRI scans every 6 months and cerebral angiograms 3-years after radiosurgery. 44 patients had observation period longer than 24 months. From them 37 patients were investigated. Four patients were lost, 2 died from intercurrent diseases and 1 from AVM hemorrhage. Complete obliteration was observed in 16 patients – 43%. Partial obliteration was observed in 20 patients – 54%. From them 10 patients had 80-99% AVM volume obliteration, 7 – 50–79% and 3 – 10–49%. One patient had no effect. Symptomatic brain edema developed in 3 patients, asymptomatic in 13. Radiation necrosis developed in 1 patient. Case examples are shown in pictures.