OJRad  Vol.4 No.4 , December 2014
Evaluation of 3-D Printed Immobilisation Shells for Head and Neck IMRT
This paper presents the preclinical evaluation of a novel immobilization system for patients undergoing external beam radiation treatment of head and neck tumors. An immobilization mask is manufactured directly from a 3-D model, built using the CT data routinely acquired for treatment planning so there is no need to take plaster of Paris moulds. Research suggests that many patients find the mould room visit distressing and so rapid prototyping could potentially improve the overall patient experience. Evaluation of a computer model of the immobilization system using an anthropomorphic phantom shows that >99% of vertices are within a tolerance of ±0.2 mm. Hausdorff distance was used to analyze CT slices obtained by rescanning the phantom with a printed mask in position. These results show that for >80% of the slices the median “worse-case” tolerance is approximately 4 mm. These measurements suggest that printed masks can achieve similar levels of immobilization to those of systems currently in clinical use.

Cite this paper
Fisher, M. , Applegate, C. , Ryalat, M. , Laycock, S. , Hulse, M. , Emmens, D. and Bell, D. (2014) Evaluation of 3-D Printed Immobilisation Shells for Head and Neck IMRT. Open Journal of Radiology, 4, 322-328. doi: 10.4236/ojrad.2014.44042.
[1]   ICRU (1999) ICRU Report 62: Prescribing, Recording and Reporting Photon Beam Therapy (Supplement to ICRU Report 50). ICRU, Bethesda.

[2]   Stroom, J.C. and Heijmen, B.J. (2002) Geometrical Uncertainties, Radiotherapy Planning Margins, and the ICRU-62 Report. Radiotherapy and Oncology, 64, 75-83.

[3]   Macmillan Cancer Support (2013) Making a Radiotherapy Mask. [Online]

[4]   Fuss, M., Salter, B.J., Cheek, D., Sadeghi, A., Hevezi, J.M. and Herman, T.S. (2004) Repositioning Accuracy of a Commercially Available Thermoplastic Mask System. Radiotherapy and Oncology, 71, 339-345.

[5]   The Royal College of Radiologists, Society and College of Radiographers, Institute of Physics and Engineering in Medicine (2008) On Target: Ensuring Geometric Accuracy in Radiotherapy. The Royal College of Radiologists, London.

[6]   Nutting, C., Bidmead, A. and Henk, J. (2003) Geometric Uncertainties in Radiotherapy of Head and Neck Cancer. In: McKenzie, A., Ed., Geometric Uncertainties in Radiotherapy: Defining the Planning Target Volume, The British Institute of Radiology, London, 127-141.

[7]   Gilbeau, L., Octave-Prignot, M., Loncol, T., Renard, L., Scalliet, P. and Grégoire, V. (2001) Comparison of Setup Accuracy of Three Different Thermoplastic Masks for the Treatment of Brain and Head and Neck Tumors. Radiotherapy and Oncology, 58, 155-62.

[8]   Rotondo, R.L., Sultanem, K., Lavoie, I., Skelly, J. and Raymond, L. (2008) Comparison of Repositioning Accuracy of Two Commercially Available Immobilization Systems for Treatment of Head-and-Neck Tumors Using Simulation Computed Tomography Imaging. International Journal of Radiation Oncology, Biology, Physics, 70, 1389-1396.

[9]   Christiansen, R., Hansen, C., Nielsen, T., Johansen, J. and Brink, C. (2012) Comparison of Three Immobilisation Systems for Radiation Therapy in Head and Neck Cancer. Radiotherapy & Oncology, 103, S106.

[10]   Goiato, M., Pesqueira, A. and dos Santos, D. (2011) Prototyping for Surgical and Prosthetic Treatment. The Journal of Craniofacial Surgery, 22, 914-917.

[11]   McKernan, B., Bydder, S., Deans, T., Nixon, M. and Joseph, D. (2007) Surface Laser Scanning to Routinely Produce Casts for Patient Immobilization during Radiotherapy. Australasian Radiology, 51, 150-153.

[12]   de Beer, D.J., Truscott, M., Booysen, G.J., Barnard, L.J. and van der Walt, J.G. (2005) Rapid Manufacturing of Patient-Specific Shielding Masks, Using RP in Parallel with Metal Spraying. Rapid Prototyping Journal, 11, 298-303.

[13]   Laycock, S.D., Hulse, M., Scrase, C.D., Tam, M.D., Isherwood, S., Mortimore, D.B., Emmens, D., Patman, J., Short, S.C. and Bell, G.D. (2014) Towards the Production of Radiotherapy Treatment Shells on 3D Printers Using Data Derived from DICOM CT and MRI: Preclinical Feasibility Studies. Journal of Radiotherapy in Practice, 1-7.

[14]   Otsu, N. (1979) A Threshold Selection Method from Gray-Level Histograms. IEEE Transactions on Systems, Man and Cybernetics, 9, 62-66.

[15]   Huttenlocher, D., Klanderman, G. and Rucklidge, W. (1993) Comparing Images Using the Hausdorff Distance. IEEE Transactions on Pattern Analysis and Machine Intelligence, 15, 850-863.