title: Patient specific 3D printed phantom for IMRT quality assurance.
abstract: The purpose of this study was to test the feasibility of a patient specific phantom for patient specific dosimetric verification.Using the head and neck region of an anthropomorphic phantom as a substitute for an actual patient, a soft-tissue equivalent model was constructed with the use of a 3D printer. Calculated and measured dose in the anthropomorphic phantom and the 3D printed phantom was compared for a parallel-opposed head and neck field geometry to establish tissue equivalence. A nine-field IMRT plan was constructed and dose verification measurements were performed for the 3D printed phantom as well as traditional standard phantoms.The maximum difference in calculated dose was 1.8% for the parallel-opposed configuration. Passing rates of various dosimetric parameters were compared for the IMRT plan measurements; the 3D printed phantom results showed greater disagreement at superficial depths than other methods.A custom phantom was created using a 3D printer. It was determined that the use of patient specific phantoms to perform dosimetric verification and estimate the dose in the patient is feasible. In addition, end-to-end testing on a per-patient basis was possible with the 3D printed phantom. Further refinement of the phantom construction process is needed for routine use.
authors.affiliation: Department of Radiation Oncology, University of Minnesota, MMC494, 420 Delaware Street SE, Minneapolis, MN 55455, USA.
authors.forename: Eric D
authors.initials: ED
authors.lastname: Ehler
authors.forename: Brett M
authors.initials: BM
authors.lastname: Barney
authors.forename: Patrick D
authors.initials: PD
authors.lastname: Higgins
authors.forename: Kathryn E
authors.initials: KE
authors.lastname: Dusenbery
mesh_terms: D005373:Film Dosimetry / Q000295:instrumentation / Q000379:methods; D006801:Humans; D019047:Phantoms, Imaging; D011785:Quality Assurance, Health Care / Q000592:standards*; D011879:Radiotherapy Dosage; D011880:Radiotherapy Planning, Computer-Assisted / Q000379:methods*; D020266:Radiotherapy, Conformal / Q000592:standards*; D014062:Tongue Neoplasms / Q000473:pathology / Q000532:radiotherapy*