Science News

Three-Dimensional Printing for Construction of Tissue-Equivalent Anthropomorphic Phantoms and Determination of Conceptus Dose.

A new interesting article has been published in AJR Am J Roentgenol. 2018 Dec;211(6):1283-1290. doi: 10.2214/AJR.17.19489. Epub 2018 Oct 24. and titled:

Three-Dimensional Printing for Construction of Tissue-Equivalent Anthropomorphic Phantoms and Determination of Conceptus Dose.

Authors of this article are:

Hoerner MR, Maynard MR, Rajon DA, Bova FJ, Hintenlang DE.

A summary of the article is shown below:

OBJECTIVE: The purpose of this study was to develop a road map for rapid construction of anthropomorphic phantoms from computational human phantoms for use in diagnostic imaging dosimetry studies. These phantoms are ideal for performing pregnant-patient dosimetry because the phantoms imitate the size and attenuation properties of an average-sized pregnant woman for multiple gestational periods.MATERIALS AND METHODS: The method was derived from methods and materials previously described but adapted for 3D printing technology. A 3D printer was used to transform computational models into a physical duplicate with small losses in spatial accuracy and to generate tissue-equivalent materials characterized for diagnostic energy x-rays. A series of pregnant abdomens were selected as prototypes because of their large size and complex modeling. The process involved the following steps: segmentation of anatomy used for modeling; transformation of the computational model into a printing file format; preparation, characterization, and introduction of phantom materials; and model removal and phantom assembly.RESULTS: The density of the homogenized soft tissue-equivalent substitute was optimized by combining 9.0% by weight of urethane filler powder and 91.0% urethane polymer, which resulted in a mean density of 1.041 g/cm3 measured over 20 samples. Density varied among all of the samples by 0.0026 g/cm3. The total variation in density was 0.00261 g/cm3. The half-value layer of the bone material was measured to be 1.7 mm of bone material at 120 kVp and when simulated by use of the density of the bone tissue-equivalent substitute (1.60 g/cm3) was determined to be 1.61 mm of bone tissue. For dosimetry purposes the phantom provided excellent results for evaluating a site’s protocol based on scan range.CONCLUSION: The 3D printing technology is applicable to the fabrication of phantoms used for performing dosimetry. The tissue-equivalent materials used to substitute for the soft tissue were developed to be highly adaptable for optimization based on the dosimetry application. Use of this method resulted in more automated phantom construction with decreased construction time and increased out-of-slice spatial resolution of the phantoms.

Check out the article’s website on Pubmed for more information:



This article is a good source of information and a good way to become familiar with topics such as:

3D printing;anthropomorphic phantom;rapid prototyping

.

Categories: Science News