Electron Density Phantom

Model 062M
CORRELATE CT NUMBER AND TISSUE ELECTRON DENSITY

Because CT scans are used to correct for tissue inhomogeneities in radiotherapy treatment planning, it’s important to obtain a precise relationship between CT number (in Hounsfield units) and electron densities. The Model 062M Electron density phantom enables precise correlation of CT data to electron density of various tissues and is manufactured from CIRS tissue equivalent materials.

The Model 062M consists of two nested disks made from Plastic Water ® -LR. They can represent both head and abdomen configurations. Nine different tissue equivalent electron density plugs can be positioned at 17 different locations within the scan field. Included is a water vial plug that can be filled with any fluid. Optional distance marker plugs enable quick assessment of the CT scanner’s distance measurement accuracy.

Physicists performing treatment planning need accurate tools to evaluate CT scan data, correct for inhomogeneities and to document the relationship between CT number and tissue density. To improve the accuracy of your treatment planning, consider the CIRS Model 062 Electron Density Phantom.

The 062M is just one of three configurations available as a part of the Cone Beam CT Electron Density & Image Quality Phantom System.

Features:
  • Evaluate CT scan data
  • Correct for inhomogeneities
  • Document relationship between CT number and tissue electron density
  • Simulate indicated tissue within the diagnostic energy range
  • Quick assessment of distance registration

NOTE: This product or an optional accessory of this product requires a CIRS dosimetry cavity code before an order can be placed. Please refer to the Dosimetry Cavity Codes document to identify the CIRS code for the probe you intend to use with this product.

Data Sheet

Electron Density Phantom: Data Sheet

Brochure

CBCT Electron Density & Image Quality Phantom System: Brochure

Dosimetry Cavity Codes

Cavity Codes for Dosimetry Devices

Kolarevic, Goran; Jaroš, Dražan; Pavičar, Bojan; Ignjć, Tatjana; Kostovski, Aleksandar; Marosevic, Goran; Predojević, Branko; Mirjanić, Dragoljub; 'Computed tomography simulator conversion curve dependence on scan parameters and phantom dimension'. 2021; View

Summary: The paper describes commissioning of a Varian Halcyon 1.0 linear accelerator, in which the Model 62M was used to calibrate CBCT image data to electron density units for the Eclipse Treatment Planning System while final end-to-end testing was performed using the Model 002LFC IMRT Thorax Phantom.
Yang, Bo; Yu, Lang; Wang, Zhiqun; Wang, Bei; Li, Wenbo; Zhang, Jie; Zhang, Xin; Wu, Zhufeng; Zhou, Zongkai; Sui, Hui; 'Experience on Commissioning the first Halcyon Linear Accelerator in China'. Journal of Health Sciences. 2020; View
Hu, Yunfei; Byrne, Mikel; Archibald-Hareen, Ben; Collett, Nick; Liu, Guilin; Aland, Trent 'Validation of the preconfigured Varian Ethos Acuros XB Beam Model for treatment planning dose calculations: A dosimetric study.'. Journal of Applied Clinical Medical Physics. 2020; View
NIAMSAWAN, SASIPRAPA; Sookpeng, Supawitoo; 'The Impact of the variation of computed tomography simulation parameters to dose calculation in computer treatment planning for lung cancer patient'. 2021; Naresuan University.
Al-Hayek, Yazan; Spuur, Kelly; Davidson, Rob; Hayre, Christopher; Zheng, Xiaoming; 'The Impact of Vertical Off-Centring, Tube Voltage and Phantom Size on CT Numbers: An Experimental Study'. View

Summary: Dedicated CT-to-ED phantom was scanned at 120 kV and 140 kV, to obtain CT-to-ED (ED- Electron Density) conversion curves as well as CTDIvol. Thoracal phantoms were scanned in standard and extended field of view to evaluate dosimetric effect on treatment planning and delivery.
Pettersson, E; Bäck, A; Thilander-Klang, A; 'Comparison of Metal Artefacts for Different Dual Energy CT Techniques'. Radiation Oncology. 2021; 16 (1): 10-Jan. BioMed Central. View

Summary: In this comparison of two methods for obtaining dual-energy CT (DECT) images, performed with the 062M Electron Density Phantom, fast kV-switching was found to more accurately depict metal inserts than dual-source DECT.
Moteghaed, Niloofar Yousefi; Mostaar, Ahmad; Maghooli, Keivan; Houshyari, Mohammad; Ameri, Ahmad; 'Estimation and evaluation of pseudo-CT images using linear regression models and texture feature extraction from MRI images in the brain region to design external radiotherapy planning'. International Journal of Particle Therapy. 2021; 8 (1): 62-72. The Particle Therapy Co-operative Group.

Summary: In this effort to develop Pseudo-CT planning images from MRIs of the head, the 62M electron density phantom was used to verify the accuracy of the HU-to-electron density measurement obtained from the reference CT scan.
Kim, Bitbyeol; Junga, Seongmoon; Sona, Jaeman; Choi, Chang Heon; Kim, Jung-in; Park, Jong Min; 'Estimation of Effective Atomic Number using Dual-Energy Imaging of CT Simulator for Radiation Therapy'. Radiation Protection Dosimetry. 2021; View

Summary: Measurements of electron density were used to estimate effective atomic numbers with a CT simulator. Implementation of appropriate noise reduction techniques is recommended before this technique can replace DECT measurements.
Yoonc, Euntaek; Junga, Seongmoon; Sona, Jaeman; Kimc, Bitbyeol; Choia, Chang Heon; Parka, Jong Min; 'Dose calculation on dual energy CT images for carbon ion therapy using TOPAS: a Monte Carlo Study'. Reports of Practical Oncology & Radiotherapy. 2020; 25 (5): 738-745. Elsevier. View

Summary: Single-energy CT reference data from the 62M was used to create an effective atomic number (Zeff) of each tissue imaged under dual-energy CT. Zeff was was then used model dose delivery during carbon ion radiotherapy using the TOPAS Model Carlo simulation.
Abascal, Juan FPJ; Ducros, Nicolas; Pronina, Valeriya; Rit, Simon; Rodesch, Pierre-Antoine; Broussaud, Thomas; Bussod, Suzanne; Douek, Philippe C; Hauptmann, Andreas; Arridge, Simon; 'Material Decomposition in Spectral CT using deep learning: A Sim2Real transfer approach'. Transaction of the Korean Nuclear Society Virtual Autumn Meeting. 2020; View

Summary: Testing of a deep-learning algorithm designed to improve the speed and accuracy of spectral CT systems, performed in part on the CIRS Model 62M, is described.
Petrović, Borislava S; Faj, Dario Z; Marković, Mladen B; Tot, Arpad A; Marjanović, Milana S; Kasabašić, Mladen D; Gencel, Ivan V; Paunović, Dragomir R; Stanković, Jelena V; Krestić-Vesović, Jelena; 'Assessment of ct simulators used in radiotherapy treatment planning in Serbia, Croatia and Bosnia and Herzegovina'. JOURNAL OF APPLIED CLINICAL MEDICAL PHYSICS. 2012; 13 (1): 14-26. View
Brevitt, Barrington A; Suarez, Edwin Ges; Clemente, Rafael A Miller; Voutchkov, Mitko; 'Evaluating the Impact of CT Scanning Parameters on Dose Calculations by the Treatment Planning System in External Beam Radiation Therapy'. Transaction of the Korean Nuclear Society Virtual Autumn Meeting. 2020; View
Nakao, Minoru; Ozawa, Shuichi; Miura, Hideharu; Yamada, Kiyoshi; Habara, Kosaku; Hayata, Masahiro; Kusaba, Hayate; Kawahara, Daisuke; Miki, Kentaro; Nakashima, Takeo; 'Development of a CT number calibration audit phantom in photon radiation therapy: A pilot study'. 2020; View
Brindhaban, A; Jassim, O; 'Effect of X-ray beam energy and image reconstruction technique on computed tomography numbers of various tissue equivalent materials'. Journal of Radiation Protection and Research. 2020; 45 (4): 171-177. Korean Association for Radiation Protection.
Hu, Yanle; Ding, Xiaoning; Shen, Jiajian; Bues, Martin; Liu, Wei; Kang, Yixiu; Leng, Shuai; Yu, Lifeng; 'Feasibility of using megavoltage computed tomography to reduce proton range uncertainty: A simulation study'. Scientific RepoRtS. 2020; 10 (1): 44206. Nature Publishing Group. View
Sudhyadhom, Atchar; 'On the molecular relationship between Hounsfield Unit (HU), mass density, and electron density in computed tomography (CT)'. BioResources. 2020; 15 (3): 5558-5576. View
Zheng, Xiaoming; Al-Hayek, Yazan; Cummins, Chris; 'CORRECTION FOR CT NUMBER CHANGES CAUSED BY OFF-CENTRE PATIENT POSITIONING: A PHANTOM STUDY'. Medical physics. 2020; 47 (4): 1509-1522. Wiley Online Library. View
Gayou, Oliver 'Influence of acquisition parameters on MV-CBCT image quality'. Cureus. 2021; 13 (6): Cureus.
Jung, Seongmoon; Kim, Bitbyeol; Kim, Jung-in; Park, Jong Min; Choi, Chang Heon; 'Deriving the Effective Atomic Number with a Dual-Energy Image Set Acquired by the Big Bore CT Simulator'. IEEE Access. 2021; 9: 25632-25647. IEEE. View
Cavalcanti, Lucas de Brito; Santos, Maíra Ribeiro dos; 'Validation of the tomography calibration curve for the Radiotherapy planning system at the National Cancer Institute'. Radiography. 2021; 27 (1): 95-100. WB Saunders. View
Jensen, Garrett L; Gaddipati, Ravi; Hammonds, Kendall P; Morrow, Andrew; Swanson, Gregory P; 'Bone Density Changes Following Radiotherapy to Vertebral Metastases'. Applied Radiation and Isotopes. 2021; View
Kassaee, Anthony; Cheng, Chingyun; Yin, Lingshu; Zou, Wei; Li, Taoran; Lin, Alexander; Swisher-McClure, Samuel; Lukens, John N; Lustig, Robert A; O'Reilly, Shannon; 'Dual-Energy Computed Tomography Proton-Dose Calculation with Scripting and Modified Hounsfield Units'. Journal of Applied Clinical Medical Physics. 2021; View
Gong, Hao; Tao, Shengzhen; Gagneur, Justin D; Liu, Wei; Shen, Jiajian; McCollough, Cynthia H; Hu, Yanle; Leng, Shuai; 'Implementation and experimental evaluation of Mega-voltage fan-beam CT using a linear accelerator'. Applied Radiation and Isotopes. 2021; 170: 109601. Pergamon. View
Zheng, Xiaoming; Al-Hayek, Yazan; Cummins, Chris; Li, Xiaotian; Nardi, Laura; Albari, Khaled; Evans, James; Roworth, Evan; Seaton, Ty; 'Body size and tube voltage dependent corrections for Hounsfield Unit in medical X-ray computed tomography: theory and experiments'. 19th Asian Oceanian Congress of Radiology. 2021; View
Andersson, P; Pettersson, N; Lindberg, A; Swanpalmer, J; Chakarova, R; 'Effects of lung tissue characterization in radiotherapy of breast cancer under deep inspiration breath hold when using Monte Carlo dosimetry'. Physica Medica. 2021; 90: 83-90. Elsevier. View
Oria, Carmen Seller; Marmitt, Gabriel G; Free, Jeffrey; Langendijk, Johannes A; Both, Stefan; Knopf, Antje-Christin; Meijers, Arturs; 'Optimizing calibration settings for accurate water equivalent path length assessment using flat panel proton radiography'. Physics in Medicine & Biology. 2021; IOP Publishing. View
Alaka, BG; Bentefour, El H; Chirvase, Cezarina; Samuel, Deepak; Teo, Boon-Keng Kevin; 'Feasibility of energy-resolved dose imaging technique in pencil beam scanning mode'. View
Puvanasunthararajah, Sathyathas; Fontanarosa, Davide; Wille, Marie‐Luise; Camps, Saskia M; 'The application of metal artifact reduction methods on computed tomography scans for radiotherapy applications: A literature review'. Biomedical Physics & Engineering Express. 2020; 6 (6): 65009. IOP Publishing. View
Salas Ramirez, Maikol; 'Methods to Improve Bone Marrow Dosimetry in Molecular Radiotherapy'. Journal of Applied Clinical Medical Physics. 2021; View

References

Model: 062M Modalities: ,