DOI QR코드

DOI QR Code

Characteristic Changes Observation of N-isopropylacrylamide Phantom by Repeated Ultrasound Irradiation

초음파 반복 조사에 따른 NIPAM 팬텀의 특성 변화 관찰

  • Kim, Ju-Young (Department of Biomedical Engineering, Inje University) ;
  • Kim, Jae-Young (Department of Biomedical Engineering, Inje University) ;
  • Noh, Si-Cheol (Department of Radiological Science, International University of Korea) ;
  • Choi, Heung-Ho (Department of Biomedical Engineering, Inje University)
  • Received : 2015.10.16
  • Accepted : 2015.12.25
  • Published : 2015.12.31

Abstract

In this study, we evaluated the thermal denaturation characteristics of reusable NIPAM tissue mimicking (TM) Phantom by measuring the thermal sensitivity. And the changes of acoustic characteristic and thermal denaturation shape in NIPAM TM phantom according to the number of re-use time and re-use period were observed. With the result, as the sonication time is increased, the sound velocity of NIPAM phantom was decreased by 100 m/s and the attenuation was increased slightly. However, the changes according to the re-use period was not observed. In the thermal denaturation shape and size observation by ultrasound sonicaton, the remarkable changes have not been confirmed. With the result of this study, NIPAM Phantom was considered appropriate to evaluate and predict the effect of therapeutic ultrasound by in repeated sonication test.

본 연구에서는 재사용이 가능한 NIPAM 팬텀의 열적 민감도를 측정하여 조직유사 팬텀의 열변성 특성을 평가하였으며, 초음파 재사용 횟수와 재사용 기간에 따른 음향학적 특성 및 열 변성 형태 특성을 관찰하였다. 측정 결과조사 횟수가 증가함에 따라 NIPAM 팬텀의 음속은 100 m/s 정도 감소하고 감쇠계수는 조금 증가하는 경향을 보였다. 반면에 재사용 기간에 따른 변화는 관찰되지 않았다. 초음파 조사에 따른 열변성의 형태 및 크기는 유효할 정도의 변화는 확인되지 않았다. 본 연구를 통하여 NIPAM 팬텀이 반복 조사를 통한 초음파 치료 평가에도 적합한 것으로 판단되었다.

Keywords

References

  1. X. G. Liang, X. S. Ge, Y. P. Zhang, et al., "A convenient method of measuring the thermal conductivity of biological tissue." Phys. Med. Biol., Vol. 36, No. 12, pp.1599-1605, 1991. https://doi.org/10.1088/0031-9155/36/12/005
  2. G. ter Haar, "Therapeutic applications of ultrasound", Progress in biophysics and molecular biology, Vol. 93, No. 1, pp.111-129, 2007. https://doi.org/10.1016/j.pbiomolbio.2006.07.005
  3. K. Tauer, D. Gau, S. Schulze, et al., "Thermal property changes of poly (N-isopropylacrylamide) microgel particles and block copolymers", Colloid Polym Sci, Vol. 287, No. 3, pp.299-312.2009. https://doi.org/10.1007/s00396-008-1984-x
  4. M. K. Sun, J. Shieh, C. W. Lo, et al., "Reusable tissue-mimicking hydrogel phantoms for focused ultrasound ablation", Ultrasonics sonochemistry, Vol. 23, pp.399-405, 2015. https://doi.org/10.1016/j.ultsonch.2014.10.008
  5. L. M. Cannon, A. J. Fagan, J. E. Browne, "Novel Tissue Mimicking Materials High Frequency Breast Ultrasound Phantoms", Ultrasound in Med. & Biol., Vol.37, No. 1, pp.122-135, 2011. https://doi.org/10.1016/j.ultrasmedbio.2010.10.005
  6. M. McDonald, S. Lochhead, R. Chopra et al., "Multi-modality tissue-mimicking phantom for thermal therapy," Physics in Medicine and Biology, Vol. 49, No. 13, pp.2767-2778, 2004. https://doi.org/10.1088/0031-9155/49/13/001
  7. X. Cheng, H. E. Canavan, M. J. Stein, et al., "Surface chemical and mechanical properties of plasma-polymerized N-isopropylacrylamide", Langmuir, Vol. 21, No. 17, pp.7833-7841, 2005. https://doi.org/10.1021/la050417o
  8. A. F. Prokop, S. Vaezy, M. L. Noble, et al., "Polyacrylamide gel as an acoustic coupling medium for focused ultrasound therapy", Ultrasound in medicine & biology, Vol. 29, No. 9, pp.1351-1358, 2003. https://doi.org/10.1016/S0301-5629(03)00979-7
  9. R. Ortega, A. Tellez, L. Leija et al., "Measurement of Ultrasonic properties of Muscle and Blood Biological Phantom", Physics Procedia., Vol. 3, No.1, pp.627-634, 2009. https://doi.org/10.1016/j.phpro.2010.01.079
  10. J. H. Min, J. Y. Kim, S. C. Noh, et al., "Development of Human-Head-Mimicking Phantom for Brain Treatment Using Focused Ultrasound", J. Korean. Soc. Radiol., Vol. 7, No. 6, pp.433-439, 2013. https://doi.org/10.7742/jksr.2013.7.6.433