Technical Note: ADAM PETer – An anthropomorphic, deformable and multimodality pelvis phantom with positron emission tomography extension for radiotherapy

Gillmann, Clarissa; Homolka, N.; Johnen, W.; Runz, A.; Echner, G.; Pfaffenberger, A.; Mann, P.; Schneider, Verena; Hoffmann, Aswin L.; Troost, Esther G.C.; Koerber, Stefan A.; Kotzerke, Jörg; Beuthien‐Baumann, Bettina

doi:10.1002/mp.14597

Cited by 7 publications

(25 citation statements)

References 24 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Agarose, gelatin and methyl-cellulose gels are used more widely as soft tissue surrogates in several phantoms identified for this review [ 13 , 14 , 20 – 23 ]. The ability to customise the MRI relaxation properties of gels with relative ease at manufacture by varying the concentration of gelling and contrast agents, demonstrated extensively by Gillmann et al [ 21 ], allows for flexibility in the number of tissue types represented. Gels can be used to fill cavities or moulded to hold structure without a casing, both of which provided a reproducible geometry.…”

Section: Materials In Phantom Designmentioning

confidence: 99%

“…Phantoms with bone surrogates were most commonly created in house using gypsum plaster [ 19 , 21 , 29 ] doped with iodine CT contrast agents and either gadolinium MRI contrast agents or copper sulphate to modify the linear attenuation coefficient and relaxation times respectively. Chandramohan et al [ 29 ] assessed the radiological properties of several samples of gypsum plaster mixed with varying concentrations of each doping agent for comparison with human bone.…”

Section: Materials In Phantom Designmentioning

confidence: 99%

“…Harries et al [ 19 ] casted a skull from iodine doped plaster, which is classified as bone in five out of six MRI-based attenuation maps, but results in an underestimation of PET activity within the phantom of on average 5%, to a maximum of 11%. Gillmann et al [ 21 ] took additional steps to create bone structures that also include a bone marrow surrogate of petroleum jelly mixed with dipotassium hydroxide, allowing for lesions to be place inside. As the use of PET/MRI in areas of the body with larger bone structures increases, the differentiation between cortical bone and other features such as bone marrow may become more relevant in phantom experiments.…”

Section: Materials In Phantom Designmentioning

confidence: 99%

“…Fats are largely ignored across the phantoms produced, with only individual use of silicone [ 19 ] and peanut oil [ 21 ]. Of these materials, peanut oil provided MRI relaxation properties close to those of adipose tissue, whilst silicone exhibits a much shorter T2* [ 19 ].…”

Section: Materials In Phantom Designmentioning

confidence: 99%

“…Of the phantoms featured in this review, the Iida phantom [ 17 ] provided attenuation properties for the 3D printed polymer and Talalwa et al [ 31 ] demonstrated the dielectric properties of their proposed porous MRI-visible 3D printed polymer made of a PU/PVA mix. Gillman et al [ 21 ] reported the CT Hounsfield units and MRI relaxation times for VeroClear (Stratasys) but this is not referenced to any tissue value, suggesting it was not selected to exhibit tissue equivalent properties.…”

Section: Materials In Phantom Designmentioning

confidence: 99%

See 4 more Smart Citations

Multimodal phantoms for clinical PET/MRI

2021

View full text Add to dashboard Cite

Phantoms are commonly used throughout medical imaging and medical physics for a multitude of applications, the designs of which vary between modalities and clinical or research requirements. Within positron emission tomography (PET) and nuclear medicine, phantoms have a well-established role in the validation of imaging protocols so as to reduce the administration of radioisotope to volunteers. Similarly, phantoms are used within magnetic resonance imaging (MRI) to perform quality assurance on clinical scanners, and gel-based phantoms have a longstanding use within the MRI research community as tissue equivalent phantoms. In recent years, combined PET/MRI scanners for simultaneous acquisition have entered both research and clinical use. This review explores the designs and applications of phantom work within the field of simultaneous acquisition PET/MRI as published over the period of a decade. Common themes in the design, manufacture and materials used within phantoms are identified and the solutions they provided to research in PET/MRI are summarised. Finally, the challenges remaining in creating multimodal phantoms for use with simultaneous acquisition PET/MRI are discussed. No phantoms currently exist commercially that have been designed and optimised for simultaneous PET/MRI acquisition. Subsequently, commercially available PET and nuclear medicine phantoms are often utilised, with CT-based attenuation maps substituted for MR-based attenuation maps due to the lack of MR visibility in phantom housing. Tissue equivalent and anthropomorphic phantoms are often developed by research groups in-house and provide customisable alternatives to overcome barriers such as MR-based attenuation correction, or to address specific areas of study such as motion correction. Further work to characterise materials and manufacture methods used in phantom design would facilitate the ability to reproduce phantoms across sites.

show abstract

Section: Materials In Phantom Designmentioning

confidence: 99%

Section: Materials In Phantom Designmentioning

confidence: 99%

Section: Materials In Phantom Designmentioning

confidence: 99%

Section: Materials In Phantom Designmentioning

confidence: 99%

Section: Materials In Phantom Designmentioning

confidence: 99%

See 3 more Smart Citations

Multimodal phantoms for clinical PET/MRI

2021

View full text Add to dashboard Cite

show abstract

Technical Note: On the feasibility of performing dosimetry in target and organ at risk using polymer dosimetry gel and thermoluminescence detectors in an anthropomorphic, deformable, and multimodal pelvis phantom

et al. 2021

Self Cite

View full text Add to dashboard Cite

Objective To assess the feasibility of performing dose measurements in the target (prostate) and an adjacent organ at risk (rectum) using polymer dosimetry gel and thermoluminescence detectors (TLDs) in an anthropomorphic, deformable, and multimodal pelvis phantom (ADAM PETer). Methods The 3D printed prostate organ surrogate of the ADAM PETer phantom was filled with polymer dosimetry gel. Nine TLD600 (LiF:Mg,Ti) were installed in 3 × 3 rows on a specifically designed 3D‐printed TLD holder. The TLD holder was inserted into the rectum at the level of the prostate and fixed by a partially inflated endorectal balloon. Computed tomography (CT) images were taken and treatment planning was performed. A prescribed dose of 4.5 Gy was delivered to the planning target volume (PTV). The doses measured by the dosimetry gel in the prostate and the TLDs in the rectum (“measured dose”) were compared to the doses calculated by the treatment planning system (“planned dose”) on a voxel‐by‐voxel basis. Results In the prostate organ surrogate, the 3D‐γ‐index was 97.7% for the 3% dose difference and 3 mm distance to agreement criterium. In the center of the prostate organ surrogate, measured and planned doses showed only minor deviations (<0.1 Gy, corresponding to a percentage error of 2.22%). On the edges of the prostate, slight differences between planned and measured doses were detected with a maximum deviation of 0.24 Gy, corresponding to 5.3% of the prescribed dose. The difference between planned and measured doses in the TLDs was on average 0.08 Gy (range: 0.02–0.21 Gy), corresponding to 1.78% of the prescribed dose (range: 0.44%–4.67%). Conclusions The present study demonstrates the feasibility of using polymer dosimetry gel and TLDs for 3D and 1D dose measurements in the prostate and the rectum organ surrogates in an anthropomorphic, deformable and multimodal phantom. The described methodology might offer new perspectives for end‐to‐end tests in image‐guided adaptive radiotherapy workflows.

show abstract