Positional uncertainties of cervical and upper thoracic spine in stereotactic body radiotherapy with thermoplastic mask immobilization
Radiation Oncology Journal
; : 122-128, 2018.
Artigo
em Inglês
| WPRIM (Pacífico Ocidental)
| ID: wpr-741941
Biblioteca responsável:
WPRO
ABSTRACT
PURPOSE:
To investigate positional uncertainty and its correlation with clinical parameters in spine stereotactic body radiotherapy (SBRT) using thermoplastic mask (TM) immobilization. MATERIALS ANDMETHODS:
A total of 21 patients who underwent spine SBRT for cervical or upper thoracic spinal lesions were retrospectively analyzed. All patients were treated with image guidance using cone beam computed tomography (CBCT) and 4 degrees-of-freedom (DoF) positional correction. Initial, pre-treatment, and post-treatment CBCTs were analyzed. Setup error (SE), pre-treatment residual error (preRE), post-treatment residual error (postRE), intrafraction motion before treatment (IM1), and intrafraction motion during treatment (IM2) were determined from 6 DoF manual rigid registration.RESULTS:
The three-dimensional (3D) magnitudes of translational uncertainties (mean ± 2 standard deviation) were 3.7±3.5 mm (SE), 0.9±0.9 mm (preRE), 1.2±1.5 mm (postRE), 1.4±2.4 mm (IM1), and 0.9±1.0 mm (IM2), and average angular differences were 1.1°±1.2° (SE), 0.9°±1.1° (preRE), 0.9°±1.1° (postRE), 0.6°±0.9° (IM1), and 0.5°±0.5° (IM2). The 3D magnitude of SE, preRE, postRE, IM1, and IM2 exceeded 2 mm in 18, 0, 3, 3, and 1 patients, respectively. No association were found between all positional uncertainties and body mass index, pain score, and treatment location (p > 0.05, Mann-Whitney test). There was a tendency of intrafraction motion to increase with overall treatment time; however, the correlation was not statistically significant (p > 0.05, Spearman rank correlation test).CONCLUSION:
In spine SBRT using TM immobilization, CBCT and 4 DoF alignment correction, a minimum residual translational uncertainty was 2 mm. Shortening overall treatment time and 6 DoF positional correction may further reduce positional uncertainties.
Texto completo:
Disponível
Base de dados:
WPRIM (Pacífico Ocidental)
Assunto principal:
Radioterapia
/
Coluna Vertebral
/
Índice de Massa Corporal
/
Estudos Retrospectivos
/
Radiocirurgia
/
Incerteza
/
Tomografia Computadorizada de Feixe Cônico
/
Imobilização
/
Máscaras
/
Metástase Neoplásica
Tipo de estudo:
Guia de prática clínica
/
Estudo observacional
Limite:
Humanos
Idioma:
Inglês
Revista:
Radiation Oncology Journal
Ano de publicação:
2018
Tipo de documento:
Artigo