PENGUKURAN KUALITAS CITRA DIGITAL COMPUTED RADIOGRAPHY MENGGUNAKAN PROGRAM PENGOLAH CITRA

D. R. Ningtias, S. Suryono, S. Susilo

Abstract


Penelitian yang telah dilakukan adalah pembuatan dan penghitungan kualitas citra digital menggunakan program Modulation Transfer Function (MTF) pada sistem Computed Radiography (CR) untuk kegiatan Quality Control (QC). MTF dapat digunakan untuk menganalisis resolusi spasial citra digital secara akurat. Pada penelitian ini menggunakan phantom yang terbuat dari tembaga berukuran 15x15 cm dengan ketebalan 1 mm. Phantom dieksposi dengan variasi tegangan 50 kV, 60 kV, 70 kV dan 81 kV dan masing-masing dilakukan variasi arus. Data yang diperoleh berupa file citra digital radiografi format DICOM yang kemudian dilakukan analisis kualitas citranya menggunakan PC diluar sistem CR dengan metode MTF. Metode ini sangat efisien dalam melakukan QC resolusi spasial secara kuantitatif sehingga dapat digunakan untuk menilai kualitas pesawat CR. Hasil pengukuran menunjukkan bahwa semakin tinggi tegangan yang digunakan, maka kualitas citra semakin baik dengan arus optimal pada rentang 4-8 mAs dengan rata-rata nilai resolusi spasial 7,26 lp/mm.

The research was analyzing of digital image quality by using Modulation Transfer Function (MTF) on Computed Radiography (CR) system for Quality Control (QC). MTF can be used for analyzing digital image spatial resolution accurately. The research used phantom that made of 15x15 cm2 copper and 1 mm thickness. The phantom was expounded with voltage variations by 50 kV, 60 kV, 70 kV dan 81 kV and each of them have been taken by variations of the current. The the image quality of data obtained in the form of radiography digital image files with DICOM format were then analyzed using PC out of CR system with methode of MTF. This methode is really efficient for QC spatial resolution quantitatively and so it can be used for assesing the quality of CR. The measurement results showed that the higher the voltage, the better image quality with optimal current was on the range between 4-8 mAs with the average value of MTF 7,26 lp/mm.


Keywords


digital image; spatial resolution; MTF

Full Text:

PDF

References


Artz, D. S. (1997). Computed Radiography for the Radiological Technologist. Seminars in Roentgenology, 32(1), 12-24.

Busch, H. P., & Faulkner, K. (2005). Image Quality and Dose Management in Digital Radiography: A New Paradigm for Optimisation. Quality Assurance Reference Centre, 90(1-2), 31-33.

Bushberg, J. T., Seibert, J. A., Leidholdt, E. M., & Boone, J. M. (2002). The Essential Physics of Medical Imaging (2nd ed). Philadelphia, USA : Lippincott Williams & Wilkins.

Caroll, Q. B. (2011). Radiography in The Digital Age: Physics, Exposure, Radiation Biology. China: Charles C Thomas Publisher.

Cunningham, I. A., & Fenster, A. (1987). A method for modulation transfer function determination from edge profiles with correction for finite-element differentiation. Medical physics, 14(4), 533-537.

Estribeau, M., & Magnan, P. (2004) Fast MTF Measurement of CMOS Imagers Using ISO 12233 Slanted-Edge Methodology. Proceedings of SPIE, 5251.

Fan, W., Cao, F., & Bai, T. (2013). Modulation transfer function of spatially variant sampling retina-like sensor. Optik-International Journal for Light and Electron Optics, 124(12), 1342-1345.

Kemenkes. (2009). Pedoman Kendali Mutu Quality Control (QC) Peralatan Radiodiagnostik, Menteri Kesehatan RI, 1250.

Korner, M., Weber, C. H., Wirth, S., Pfeifer, K. J., Reiser, M. F., & Treitl, M. (2007). Advances in Digital Radiography: Physical Principles and System Overview 1. Radiographics, 27(3), 675-686.

Mah, E., Samei, E., & Peck, D. J. (2001). Evaluation of A Quality Control Phantom for Digital Chest Radiography. Journal of Applied Clinical of Medical Physics, 2(2), 1526-9914.

Muhogora, W. E., Msaki, P., & Padovani, R. (2014). Application of off-line Image Processing for Optimization in Chest Computed Radiography Using A Low Cost Systems. Journal of Applied Clinical of Medical Physics, 16(2), 322-333

Paech, A., Schulz, A. P., Hahlbrauck, B., Kiene, J., Wenzl, M. E., & Jrgens, C. (2007). Physical evaluation of a new technique for X-ray dose reduction: Measurement of signal-to-noise ratio and modulation transfer function in an animal model. Physica Medica, 23(1), 33-40.

Petkovi?, D., Shamshirband, S., Saboohi, H., Ang, T. F., Anuar, N. B., Rahman, Z. A., & Pavlovi?, N. T. (2014). Evaluation of modulation transfer function of optical lens system by support vector regression methodologiesA comparative study. Infrared Physics & Technology, 65, 94-102.

Richard, S., Husarik, D. B., Yadava, G., Murphy, S. N., & Samei, E. (2012). Towards task-based assessment of CT performance: system and object MTF across different reconstruction algorithms. Medical physics, 39(7), 4115-4122.

Samei, E., Seibert, J. A., Willis, C. E., Flynn, M. J., Mah, E., & Junck, K. L. (2001). Performance evaluation of computed radiography systems. Medical Physics, 28(3), 361-371.

Samei, E., & Flynn, M. J. (2003). An experimental comparison of detector performance for direct and indirect digital radiography systems. Medical physics, 30(4), 608-622.

Samei, E., Ranger, N. T., Dobbins III, J. T., & Chen, Y. (2006). Intercomparison of methods for image quality characterization. I. Modulation transfer functiona). Medical physics, 33(5), 1454-1465.

Suryono, S. (2011). Rancang Bangun Sistem Komputer Tomografi Ultrasonik untuk Pengujian Material Padat, Disertasi. Yogyakarta: Jurusan Fisika, Fakultas Matematika dan Ilmu Pengetahuan Alam, Universitas Gajah Mada.

Suryono, S., Kusminarto, Suparta, G. B., & Sugiharto, A. (2015). Ultrasound Computer Tomography Digital Image Processing for Concrete Hole Inspection. International Journal of Applied Engineering Research, 10(15), 35499-35503.

Yaffe, M. J., & Rowlands, J. A. (1997). X-ray detectors for digital radiography. Physics in Medicine and Biology, 42(1), 1.

Susilo, Sunarno, I Ketut Swakarma, Rudi Setiawan, Edy Wibowo. (2013). Kajian sistem radiografi digital sebagai pengganti sistem computed radiography yang mahal. Jurnal Fisika Indonesia, 17(50),1410-2994




DOI: https://doi.org/10.15294/jpfi.v12i2.5950

Refbacks

  • There are currently no refbacks.




Creative Commons License
Jurnal Pendidikan Fisika Indonesia is licensed under a Creative Commons Attribution 4.0 International Licensep-ISSN 1693-1246 e-ISSN 2355-3812