| Autor: |
G Li, Yoshiya Yamada, A Ballangrud, H Kang, A Kirov, D Lovelock, J Mechalakos, H Amols, L Kuo |
| Rok vydání: |
2011 |
| Předmět: |
|
| Zdroj: |
Medical Physics. 38:3711-3711 |
| ISSN: |
0094-2405 |
| DOI: |
10.1118/1.3612963 |
| Popis: |
Purpose: To develop an image‐guided procedure for online head‐rotation correction and real‐time motion monitoring with threshold gating for clinical frameless stereotactic radiosurgery(SRS) using video‐based optical 3D surfaceimaging (AlignRT) to ensure accurate tumor localization and clinically‐acceptable head motion at all treatment couch angles during treatment. Methods: Eight patients, immobilized with a deep‐head mold and a mouth‐piece fixed to the couch, were treated with single‐fraction frameless SRS. The planning target volume was defined by a 3.0mm‐margin around the gross tumor volume for these patients with brainmetastasis. A ceiling‐mounted AlignRT system with three camera pods was used to correct residual head rotation before cone‐beam computed tomography(CBCT) setup, verify setup at all treatment couch angles, and monitor the head motion with 1.0mm gating threshold for beam hold. The external contour of the planing CT and on‐site surface reference images were used for setup verification and motion monitoring, respectively, using the maximum visible skin surface within the entire mid‐to‐upper face as the region of interest. An anthropomorphous head phantom and an adjustable platform (accuracy of 0.1 mm) were used to determine the geometric accuracy of frameless setup procedure and AlignRT motion detection. Results: The phantom experiment shows that the motion detection accuracy was less than 0.1 mm. For these patients |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
|
Plný text