Journal article
Bone material analogues for PET/MRI phantoms
Medical physics (Lancaster), Vol.47(5), pp.2161-2170
06/01/2020
DOI: 10.1002/mp.14079
PMCID: PMC7901472
PMID: 32034945
Abstract
Purpose To develop bone material analogues that can be used in construction of phantoms for simultaneous PET/MRI systems.
Methods Plaster was used as the basis for the bone material analogues tested in this study. It was mixed with varying concentrations of an iodinated CT contrast, a gadolinium-based MR contrast agent, and copper sulfate to modulate the attenuation properties and MRI properties (T1 and T2*). Attenuation was measured with CT and Ge-68 transmission scans, and MRI properties were measured with quantitative ultrashort echo time pulse sequences. A proof-of-concept skull was created by plaster casting.
Results Undoped plaster has a 511 keV attenuation coefficient (~0.14 cm(-1)) similar to cortical bone (0.10-0.15 cm(-1)), but slightly longer T1 (~500 ms) and T2* (~1.2 ms) MR parameters compared to bone (T1 ~ 300 ms, T2* ~ 0.4 ms). Doping with the iodinated agent resulted in increased attenuation with minimal perturbation to the MR parameters. Doping with a gadolinium chelate greatly reduced T1 and T2*, resulting in extremely short T1 values when the target T2* values were reached, while the attenuation coefficient was unchanged. Doping with copper sulfate was more selective for T2* shortening and achieved comparable T1 and T2* values to bone (after 1 week of drying), while the attenuation coefficient was unchanged.
Conclusions Plaster doped with copper sulfate is a promising bone material analogue for a PET/MRI phantom, mimicking the MR properties (T1 and T2*) and 511 keV attenuation coefficient of human cortical bone.
Details
- Title: Subtitle
- Bone material analogues for PET/MRI phantoms
- Creators
- Dharshan Chandramohan - University of California, San FranciscoPeng Cao - University of California, San FranciscoMisung Han - University of California, San FranciscoHongyu An - Washington University in St. LouisJohn J. Sunderland - University of IowaPaul E. Kinahan - University of WashingtonRichard Laforest - Washington University in St. LouisThomas A. Hope - University of California, San FranciscoPeder E. Z. Larson - University of California, San Francisco
- Resource Type
- Journal article
- Publication Details
- Medical physics (Lancaster), Vol.47(5), pp.2161-2170
- DOI
- 10.1002/mp.14079
- PMID
- 32034945
- PMCID
- PMC7901472
- NLM abbreviation
- Med Phys
- ISSN
- 0094-2405
- eISSN
- 2473-4209
- Publisher
- Wiley
- Number of pages
- 10
- Language
- English
- Date published
- 06/01/2020
- Academic Unit
- Radiology; Physics and Astronomy; Radiation Oncology
- Record Identifier
- 9984312968402771
Metrics
11 Record Views