1Research Center for Molecular and Cellular Imaging, Tehran University of Medical Sciences, Tehran, Iran
2Radiation Research Center, Faculty of Paramedicine, AJA University of Medical Sciences, Tehran, Iran
3Department of Medical Physics and Biomedical Engineering, Tehran University of Medical Sciences, Tehran, Iran
Introduction:SURGEOSIGHT is a dedicated intra-operative hand-held gamma camera designed and manufactured by our team to be used for lymphoscintigraphy. Although conventional gamma cameras are widely used, they lack the capability of the sentinel lymph node (SLN) imaging in the operation room. Like conventional gamma cameras it is necessary to calibrate SURGEOSIGHT for linearity distortion, energy and flood correction. Our main objective in this study is to develop and implement three techniques for linearity, energy and uniformity corrections. Methods: The camera is made up of a pixelated cesium iodide (sodium-activated) (CsI(Na)) scintillation crystal with 1 × 1 mm2 element size along with a Hamamatsu H8500 flat-panel multi-anode (64 channels) photomultiplier tube. All triple corrections required lookup tables (LUTs). To generate all three LUTs, one uncalibrated acquisition is necessary. Linearity distortion correction was based on localization of physical pixels of crystal and thin plate spline interpolation to estimate the amount of distortion. Energy correction LUT was simply a photo-peak map of incoming events which was estimated using self-organizing map technique. Results: The results showed improvements qualitatively and quantitatively. The extrinsic energy resolution was enhanced from 50% to about 20.6%. Integral uniformity and the differential uniformity, after uniformity correction, in useful field-of-view (UFOV) was measured 9.5% and 4.5%, respectively.
Conclusion: Results substantiated that the correction techniques guarantee uniform and accurate output of the SURGEOSIGHT which is desirable for intra-operative localization of the sentinel lymph nodes in breast cancer and also for imaging of other superficial tumors.
Bischof Delaloye A. Progress in the diagnosis and treatment of disease by nuclear medicine and molecular imaging: highlights of the European Association of Nuclear Medicine Congress, Naples 2001. Eur J Nucl Med Mol Imaging. 2002 Jan;29(1):139-59.
Nishimura T. Angina pectoris: progress in diagnosis and treatment. II. Progress in imaging diagnosis. 2. The role of nuclear medicine. Nihon Naika Gakkai Zasshi. 1997 Feb 10;86(2):214-9.
Gray RM, Macovski A. Maximum a posteriori estimation of position in scintillation cameras. IEEE Trans Nucl Sci. 1976;23(1):849-52.
Barrett HH, Hunter WC, Miller BW, Moore SK, Chen Y, Furenlid LR. Maximum-likelihood methods for processing signals from gamma-ray detectors. IEEE Trans Nucl Sci. 2009 Jun 1;56(3):725.
Bruyndonckx P, Leonard S, Tavernier S, Lemaitre C, Devroede O, Wu Y, et al. Neural network-based position estimators for PET detectors using monolithic LSO blocks. IEEE Trans Nucl Sci. 2004;51(5):2520-5.
Jeong MH, Choi Y, Chung YH, Song TY, Jung JH, Hong KJ, Min BJ, Choe YS, Lee KH, Kim BT. Position mapping, energy calibration, and flood correction improve the performances of small gamma camera using PSPMT. IEEE Nucl Sci Symp Conf Rec. 19-25 October 2003.
Jeong MH, Choi Y, Chung YH, Song TY, Jung JH, Hong KJ, Min BJ, Choe YS, Lee KH, Kim BT. Performance improvement of small gamma camera using NaI(Tl) plate and position sensitive photo-multiplier tubes. Phys Med Biol. 2004 Nov 7;49(21):4961-70.
Hung N, Joung J, Lee K, Kim Y. Development of correction schemes for a small field of view gamma camera. Biomed Eng Lett. 2012;2(4):215-22.
Inbar D, Gafni G, Grimberg E, Koren J. Gamma camera correction system and method for using the same. Patent US4588897 A. 1986.
Berlad G, Wainer N. Gamma camera with two sequential correction maps. Patent US6559450 B1. 2003.
España S, Deprez K, Van Holen R, Vandenberghe S. Fast calibration of SPECT monolithic scintillation detectors using un-collimated sources. Phys Med Biol. 2013 Jul 21;58(14):4807-25.
Thanasas D, Maintas D, Georgiou E, Giokaris N, Karabarbounis A, Papanicolas CN, Stiliaris E. Correcting spatial distortion and non-uniformity in planar images from γ-Camera systems. IEEE Nucl Sci Symp Conf Rec. 19-25 October 2008.
Knoll GF, Strange DR, Bennett MC. Radiation signal processing system. Patent US4212061 A. 1980.
Muehllehner G, Colsher JG, Stoub EW. Correction for field nonuniformity in scintillation cameras through removal of spastial distortion. J Nucl Med. 1980 Aug;21(8):771-6.
Stoub EW, Colsher JG, Muehllehner G. Distortion correction method and apparatus for scintillation cameras. Patent US4298944 A. 1981.
Arseneau RE. Non-uniformity energy correction method and apparatus. Patent US4323977 A. 1982.
Arseneau RE. Dynamic threshold for scintillation camera. Patent US4475042 A. 1984.
Barfod JM. Gamma camera with image uniformity by energy correction offsets. Patent US4899054 A. 1990.
Spector SS, Brookeman VA, Kylstra CD, Diaz NJ. Analysis and correction of spatial distortions produced by the gamma camera. J Nucl Med. 1972 May;13(5):307-12.
Muehllehner G, Luig H. Septal penetration in scintillation camera collimators. Phys Med Biol. 1973 Nov;18(6):855-62.
Muehllehner G. Radiation imaging device. Patent US3745345 A. 1973.
Bertelsen H. Gamma camera with automatc adjustment of the energy spectrum. Patent US6635878 B2. 2003.
Richey JB, Wake RH, Wilson HH, Cheiky MC. Dynamic uniform flood correction for radioisotope cameras. Patent US4151416 A. 1979.
Tararine M. Method for correcting the uniformity of a gamma camera. Patent US5606166 A. 1997.
Kaviani S, Zeraatkar N, Sajedi S, Akbarzadeh A, Gorjizadeh N, Farahani MH, Teimourian B, Ghafarian P, Sabet H, Ay MR. Design and development of a dedicated portable gamma camera system for intra-operative imaging. Phys Med. 2016 Jul;32(7):889-97.
Ay M, Arabi H, Farahani M, Zeraatkar N, Sarkar S, Sajedi S, Naderi Rastgar N, Ghafarian P. SurgeoSightTM: An Intraoprative hand held gamma camera for precise localization of sentinel lymph nodes. Eur J Nucl Med Mol Imaging. 2012;39(Suppl 2):S385.
Gorjizadeh N, Zeraatkar N, Kaviani A, Far SF, Farahani M, Akbarzadeh A, Sajedi S, Teimourian B, Ay M. Performance Evaluation of a small field of view portable gamma camera for localization of sentinel lymph nodes. Eur J Nucl Med Mol Imaging. 2013;40(Suppl 2):S99.
Grau V, Mewes AU, Alcañiz M, Kikinis R, Warfield SK. Improved watershed transform for medical image segmentation using prior information. IEEE Trans Med Imaging. 2004 Apr;23(4):447-58.
Bookstein FL. Principal warps: thin-plate splines and the decomposition of deformations. IEEE Trans Pattern Anal Mach Intell. 1989;11(6):567-85.
Kohonen T. The self-organizing map. Proc IEEE. 1990;78(9):1464-80.
Cottrell M, Olteanu M, Rossi F, Villa-Vialaneix N. Theoretical and applied aspects of the self-organizing maps. In: Merényi E, Mendenhall JM, O'Driscoll P, editors. Advances in self-organizing maps and learning vector quantization. Switzerland: Springer International Publishing; 2016. p. 3-26.
de Bodt E, Cottrell M, Verleysen M. Statistical tools to assess the reliability of self-organizing maps. Neural Netw. 2002 Oct-Nov;15(8-9):967-78.
Erwin E, Obermayer K, Schulten K. Self-organizing maps: ordering, convergence properties and energy functions. Biol Cybern. 1992;67(1):47-55.
Tolat VV. An analysis of Kohonen's self-organizing maps using a system of energy functions. Biol Cybern. 1990;64(2):155-64.