Calculation of planning margins for different verification techniques in radical prostate radiotherapy

Autor:	Ian Gleeson
Rok vydání:	2013
Předmět:	Oncology medicine.medical_specialty Computer science business.industry Planning target volume Conformal radiotherapy Ptv margin Internal medicine Random error medicine Prostate radiotherapy Radiology Nuclear Medicine and imaging Fiducial marker Nuclear medicine business
Zdroj:	Journal of Radiotherapy in Practice. 13:149-158
ISSN:	1467-1131 1460-3969
Popis:	PurposeTo calculate and compare planning target volume (PTV) margins for an offline 3 mm tolerance, daily bony anatomy verification, tattoo alignment and online prostate marker matching with those currently used at our institution.MethodsSeventy patients had offline bony anatomy megavoltage verification. 23 different patients underwent fiducial marker matching using daily online kilovoltage verification. Systematic and random errors were measured in the right–left (RL), superior–inferior (SI) and anterior–posterior (AP) directions. Geometric uncertainties from literature were used to help calculate the margins.ResultsPTV margins (mm) were 7 RL, 12 SI and AP (3 mm tolerance offline bony), 6 RL, 11 SI and AP (daily online bony), 8 RL, 12 SI and AP (tattoo alignment) and 5 RL, 8 SI and 6 AP (online daily prostate marker correction).ConclusionsOur current margins for conformal radiotherapy patients are too small for phase 2 in the SI and AP directions. Implementing online daily bony anatomy matching would not reduce the PTV margin significantly. Online daily marker correction showed current PTV71 Gy margins as excessive by (mm) 5 RL, 2 SI and 4 anterior.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::665406646142640f6f86fcc97dac46c1 https://doi.org/10.1017/s1460396913000101 Zobrazit plný text záznamu