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6. Implementation, Dosimetric Assessment, and Treatment Validation of Knowledge-Based Planning (KBP) Models in VMAT Head and Neck Radiation Oncology

Author

Fanou, A.-M. Patatoukas, G. Chalkia, M. Kollaros, N. Kougioumtzopoulou, A. Kouloulias, V. Platoni, K. and Fanou, A.-M. Patatoukas, G. Chalkia, M. Kollaros, N. Kougioumtzopoulou, A. Kouloulias, V. Platoni, K.

Abstract

The aim of this study was to evaluate knowledge-based treatment planning (KBP) models in terms of their dosimetry and deliverability and to investigate their clinical benefits. Three H&N KBP models were built utilizing RapidPlan™, based on the dose prescription, which is given according to the planning target volume (PTV). The training set for each model consisted of 43 clinically acceptable volumetric modulated arc therapy (VMAT) plans. Model quality was assessed and compared to the delivered treatment plans using the homogeneity index (HI), conformity index (CI), structure dose difference (PTV, organ at risk—OAR), monitor units, MU factor, and complexity index. Model deliverability was assessed through a patient-specific quality assurance (PSQA) gamma index-based analysis. The dosimetric assessment showed better OAR sparing for the RapidPlan™ plans and for the low- and high-risk PTV, and the HI, and CI were comparable between the clinical and RapidPlan™ plans, while for the intermediate-risk PTV, CI was better for clinical plans. The 2D gamma passing rates for RapidPlan™ plans were similar or better than the clinical ones using the 3%/3 mm gamma-index criterion. Monitor units, the MU factors, and complexity indices were found to be comparable between RapidPlan™ and the clinical plans. Knowledge-based treatment plans can be safely adapted into clinical routines, providing improved plan quality in a time efficient way while minimizing user variability. © 2023 by the authors.

Published
2023

7. A step closer to automation: kilovoltage and Megavoltage Planar Imaging Quality Assurance, baseline, tolerance and action levels definition and exploration

Author

Fanou, A.-M. Kollaros, N. Patatoukas, G. Efstathopoulos, E. Platoni, K. and Fanou, A.-M. Kollaros, N. Patatoukas, G. Efstathopoulos, E. Platoni, K.

Abstract

Purpose: To establish automated quality assurance (QA) procedures for the kilovoltage (kV) and the Megavoltage (MV) imagers of two linear accelerators (LINACS) using a commercial software. Methods: SNC Machine™ phantoms and software were used and the baseline values, tolerance and action levels for various image quality parameters were defined. Scaling, spatial resolution, contrast, uniformity and noise were considered, explored and evaluated utilizing the appropriate phantoms and the accompanying software. kV and MV planar radiographic images, for 6MV and 10MV beams were obtained for each LINAC. For both kV and MV QA tasks, the baseline values for spatial resolution, contrast, uniformity and noise were defined. Results: Subsequent measurements performed were highly reproducible and within tolerance and action levels, while noise showed variations. The calculated tolerance and action levels for noise were looser compared to the other image quality metrics. Conclusions: An automated QA workflow of the kV and MV planar radiographic mode of LINAC imagers’ was established and appears to be time effective. © 2023 Associazione Italiana di Fisica Medica e Sanitaria

Published
2023

10. Implementation of TG-218 for patient-specific quality assurance tolerance and action limits determination: Gamma passing rate evaluation using 3DVH software

Author

Stasinou, D. Patatoukas, G. Kollaros, N. Diamantopoulos, S. Kypraiou, E. Kougioumtzopoulou, A. Kouloulias, V. Efstathopoulos, E. Platoni, K. and Stasinou, D. Patatoukas, G. Kollaros, N. Diamantopoulos, S. Kypraiou, E. Kougioumtzopoulou, A. Kouloulias, V. Efstathopoulos, E. Platoni, K.

Abstract

Purpose: To determine the tolerance limit (TL) and action limit (AL) of gamma passing rates (%GP) for volumetric-modulated arc therapy (VMAT) patient-specific quality assurance (PSQA) according to the American Association of Physicists in Medicine (AAPM) Task Group (TG)-218 recommendations, and to comparatively evaluate the clinical relevance of 2D %GP and 3D %GP. Methods: PSQA was performed for 100 head and neck (H&N) and 73 prostate cancer VMAT treatment plans. Measurements were acquired using a cylindrical water equivalent phantom, hollow in the center, allowing measurements with homogeneous or heterogeneous inserts. The LINAC-delivered dose distributions were compared to those calculated from the treatment planning system through the gamma index. TL and AL were determined through the computation of two-dimensional (2D) %GP using the recommended acceptance criteria. Dose–volume histograms were reconstructed from the measurements using a commercially available software to detect the dosimetric errors (%DE) between the compared dose distributions. Utilizing the estimated dose on the patient anatomy, structure-specific %GP (3D %GP) were calculated. The 3D %GP were compared to the 2D %GP ones based on their correlation with the %DE. Each metric's sensitivity was determined through receiver operator characteristic analysis. Results: TL and AL were in concordance with the universal ones, regarding the prostate cancer cases, but were lower for the H&N cases. Evaluation of %DE did not deem the plans unacceptable. The 2D %GP and the 3D %GP did not differ significantly regarding their correlation with %DE. For prostate plans, %GP sensitivity was higher than for H&N cases. Conclusions: Determination of institutional-specific TL and AL allows the monitoring of the PSQA procedure, yet for plans close to the limits, clinically relevant metrics should be used before they are deemed unacceptable for the process to be of higher sensitivity and efficiency. © 2022

Published
2022

11. Abstracts of original contributions ASNC 2004 9th annual scientific session September 3-–October 3, 2004 New York, New York

Author

Abidov, A, Hachamovitch, R, Friedman, JD, Hayes, SW, Kang, X, Cohen, I, Germano, G, Berman, DS, Kjaer, A, Cortsen, A, Federspiel, M, Hesse, B, Holm, S, O’Connor, M, Dhalla, AK, Wong, M-Y, Wang, W-Q, Belardinelli, L, Therapeutics, CV, Epps, A, Dave, S, Brewer, K, Chiaramida, S, Gordon, L, Hendrix, GH, Feng, B, Pretorius, PH, Bruyant, PP, Boening, G, Beach, RD, Gifford, HC, King, MA, Fessler, JA, Hsu, B-L, Case, JA, Gegen, LL, Hertenstein, GK, Cullom, SJ, Bateman, TM, Akincioglu, C, Abidov, A, Nishina, H, Kavanagh, P, Kang, X, Aboul-Enein, F, Yang, L, Hayes, S, Friedman, J, Berman, D, Germano, G, Santana, CA, Rivero, A, Folks, RD, Grossman, GB, Cooke, CD, Hunsche, A, Faber, TL, Halkar, R, Garcia, EV, Hansen, CL, Silver, S, Kaplan, A, Rasalingam, R, Awar, M, Shirato, S, Reist, K, Htay, T, Mehta, D, Cho, J-H, Heo, J, Dubovsky, E, Calnon, DA, Grewal, KS, George, PB, Richards, DR, Hsi, DH, Singh, N, Meszaros, Z, Thomas, JL, Reyes, E, Loong, CY, Latus, K, Anagnostopoulos, C, Underwood, SR, Kostacos, EJ, Araujo, LI, Kostacos, EJ, Araujo, LI, Lewin, HC, Hyun, MC, DePuey, EG, Tanaka, H, Chikamori, T, Igarashi, Y, Harafuji, K, Usui, Y, Yanagisawa, H, Hida, S, Yamashina, A, Nasr, HA, Mahmoud, SA, Dalipaj, MM, Golanowski, LN, Kemp, RA de, Chow, BJ, Beanlands, RS, Ruddy, TD, Michelena, HI, Mikolich, BM, McNelis, P, Decker, WA Van, Stathopoulos, I, Duncan, S- A, Isasi, C, Travin, MI, Kritzman, JN, Ficaro, EP, Corbett, JR, Allison, JS, Weinsaft, JW, Wong, FJ, Szulc, M, Okin, PM, Kligfield, P, Harafuji, K, Chikamori, T, Igarashi, Y, Tanaka, H, Usui, Y, Yanagisawa, H, Hida, S, Ishimaru, S, Yamashima, A, Giedd, KN, Bergmann, SR, Shah, S, Emmett, L, Allman, KC, Magee, M, Van Gaal, W, Kritharides, L, Freedman, B, Abidov, A, Gerlach, J, Akincioglu, C, Friedman, J, Kavanagh, P, Miranda, R, Germano, G, Berman, DS, Hayes, SW, Damera, N, Lone, B, Singh, R, Shah, A, Yeturi, S, Prasad, Y, Blum, S, Heller, EN, Bhalodkar, NC, Koutelou, M, Kollaros, N, Theodorakos, A, Manginas, A, Leontiadis, E, Kouzoumi, A, Cokkinos, D, Mazzanti, M, Marini, M, Cianci, G, Perna, GP, Pai, M, Greenberg, MD, Liu, F, Frankenberger, O, Kokkinos, P, Hanumara, D, Goheen, E, Wu, C, Panagiotakos, D, Fletcher, R, Greenberg, MD, Liu, F, Frankenberger, O, Kokkinos, P, Hanumara, D, Goheen, E, Rodriguez, OJ, Iyer, VN, Lue, M, Hickey, KT, Blood, DK, Bergmann, SR, Bokhari, S, Chareonthaitawee, P, Christensen, SD, Allen, JL, Kemp, BJ, Hodge, DO, Ritman, EL, Gibbons, RJ, Smanio, P, Riva, G, Rodriquez, F, Tricoti, A, Nakhlawi, A, Thom, A, Pretorius, PH, King, MA, Dahlberg, S, Leppo, J, Slomka, PJ, Nishina, H, Berman, DS, Akincioglu, C, Abidov, A, Friedman, JD, Hayes, SW, Germano, G, Petrovici, R, Husain, M, Lee, DS, Nanthakumar, K, Iwanochko, RM, Brunken, RC, DiFilippo, F, Neumann, DR, Bybel, B, Herrington, B, Bruckbauer, T, Howe, C, Lohmann, K, Hayden, C, Chatterjee, C, Lathrop, B, Brunken, RC, Chen, MS, Lohmann, KA, Howe, WC, Bruckbauer, T, Kaczur, T, Bybel, B, DiFilippo, FP, Druz, RS, Akinboboye, OA, Grimson, R, Nichols, KJ, Reichek, N, Ngai, K, Dim, R, Ho, K- T, Pary, S, Ahmed, SU, Ahlberg, A, Cyr, G, Vitols, PJ, Mann, A, Alexander, L, Rosenblatt, J, Mieres, J, Heller, GV, Ahmed, SU, Ahlberg, AW, Cyr, G, Navare, S, O’Sullivan, D, Heller, GV, Chiadika, S, Lue, M, Blood, DK, Bergmann, SR, Bokhari, S, Heston, TF, Heller, GV, Cerqueira, MD, Jones, PG, Bryngelson, JR, Moutray, KL, Gegen, LL, Hertenstein, GK, Moser, K, Case, JA, Zellweger, MJ, Burger, PC, Pfisterer, ME, Mueller-Brand, J, Kang, WJ, Lee, BI, Lee, DS, Paeng, JC, Lee, JS, Chung, J-K, Lee, MC, To, BN, O’Connell, WJ, Botvinick, EH, Duvall, WL, Croft, LB, Einstein, AJ, Fisher, JE, Haynes, PS, Rose, RK, Henzlova, MJ, Prasad, Y, Vashist, A, Blum, S, Sagar, P, Heller, EN, Kuwabara, Y, Nakayama, K, Tsuru, Y, Nakaya, J, Shindo, S, Hasegawa, M, Komuro, I, Liu, Y-H, Wackers, F, Natale, D, DePuey, G, Taillefer, R, Araujo, L, Kostacos, E, Allen, S, Delbeke, D, Anstett, F, Kansal, P, Calvin, JE, Hendel, RC, Gulati, M, Pratap, P, Takalkar, A, Kostacos, E, Alavi, A, Araujo, L, Melduni, RM, Duncan, S-A, Travin, MI, Isasi CR, Rivero, A, Santana, C, Esiashvili, S, Grossman, G, Halkar, R, Folks, RD, Garcia, EV, Su, H, Dobrucki, LW, Chow, C, Hu, X, Bourke, BN, Cavaliere, P, Hua, J, Sinusas, AJ, Spinale, FG, Sweterlitsch, S, Azure, M, Edwards, DS, Sudhakar, S, Chyun, DA, Young, LH, Inzucchi, SE, Davey, JA, Wackers, FJ, Noble, GL, Navare, SM, Calvert, J, Hussain, SA, Ahlberg, AM, Katten, DM, Boden, WE, Heller, GV, Shaw, LJ, Yang, Y, Antunes, A, Botelho, MF, Gomes, C, de Lima, JJP, Silva, ML, Moreira, JN, Simões, S, GonÇalves, L, Providência, LA, Elhendy, A, Bax, JJ, Schinkel, AF, Valkema, R, van Domburg, RT, Poldermans, D, Arrighi, J, Lampert, R, Burg, M, Soufer, R, Veress, AI, Weiss, JA, Huesman, RH, Gullberg, GT, Moser, K, Case, JA, Loong, CY, Prvulovich, EM, Reyes, E, Aswegen, A van, Anagnostopoulos, C, Underwood, SR, Htay, T, Mehta, D, Sun, L, Lacy, J, Heo, J, Brunken, RC, Kaczur, T, Jaber, W, Ramakrishna, G, Miller, TD, O’connor, MK, Gibbons, RJ, Bural, GG, Mavi, A, Kumar, R, El-Haddad, G, Srinivas, SM, A Alavi, El-Haddad, G, Alavi, A, Araujo, L, Thomas, GS, Johnson, CM, Miyamoto, MI, Thomas, JJ, Majmundar, H, Ryals, LA, Ip, ZTK, Shaw, LJ, Bishop, HA, Carmody, JP, Greathouse, WG, Yanagisawa, H, Chikamori, T, Tanaka, H, Usui, Y, Igarashi, U, Hida, S, Morishima, T, Tanaka, N, Takazawa, K, Yamashina, A, Diedrichs, H, Weber, M, Koulousakis, A, Voth, E, Schwinger, RHG, Mohan, HK, Livieratos, L, Gallagher, S, Bailey, DL, Chambers, J, Fogelman, I, Sobol, I, Barst, RJ, Nichols, K, Widlitz, A, Horn, E, Bergmann, SR, Chen, J, Galt, JR, Durbin, MK, Ye, J, Shao, L, Garcia, EV, Mahenthiran, J, Elliott, JC, Jacob, S, Stricker, S, Kalaria, VG, Sawada, S, Scott, JA, Aziz, K, Yasuda, T, Gewirtz, H, Hsu, BL, Moutray, K, Udelson, JE, Barrett, RJ, Johnson, JR, Menenghetti, C., Taillefer, R, Ruddy, T, Hachamovitch, R, Jenkins, SA, Massaro, J, Haught, H, Lim, CS, Underwood, R, Rosman, J, Hanon, S, Shapiro, M, Schweitzer, P, VanTosh, A, Jones, S, Harafuji, K, Giedd, K N, Johnson, N P, Berliner, J I, Sciacca, R R, Chou, R L, Hickey, K T, Bokhari, S S, Rodriguez, O, Bokhari, S, Moser, KW, Moutray, KL, Koutelou, M, Theodorakos, A, Kollaros, N, Manginas, A, Leontiadis, E, Cokkinos, D, Mazzanti, M, Marini, M, Cianci, G, Perna, GP, Nanasato, M, Fujita, H, Toba, M, Nishimura, T, Nikpour, M, Urowitz, M, Gladman, D, Ibanez, D, Harvey, P, Floras, J, Rouleau, J, Iwanochko, R, Pai, M, Guglin, ME, Ginsberg, FL, Reinig, M, Parrillo, JE, Cha, R, Merhige, ME, Watson, GM, Oliverio, JG, Shelton, V, Frank, SN, Perna, AF, Ferreira, MJ, Ferrer-Antunes, AI, Rodrigues, V, Santos, F, Lima, J, Cerqueira, MD, Magram, MY, Lodge, MA, Babich, JW, Dilsizian, V, Line, BR, Bhalodkar, NC, Lone, B, Singh, R, Prasad, Y, Yeturi, S, Blum, S, Heller, EN, Rodriguez, OJ, Skerrett, D, Charles, C, Shuster, MD, Itescu, S, Wang, TS, Bruyant, PP, Pretorius, PH, Dahlberg, S, King, MA, Petrovici, R, Iwanochko, RM, Lee, DS, Emmett, L, Husain, M, Hosokawa, R, Ohba, M, Kambara, N, Tadamura, E, Kubo, S, Nohara, R, Kita, T, Thompson, RC, McGhie, AI, O’Keefe, JH, Christenson, SD, Chareonthaitawee, P, Kemp, BJ, Jerome, S, Russell, TJ, Lowry, DR, Coombs, VJ, Moses, A, Gottlieb, SO, Heiba, SI, Yee, G, Coppola, J, Elmquist, T, Braff, R, Youssef, I, Ambrose, JA, Abdel-Dayem, HM, Canto, J, Dubovsky, E, Scott, J, Terndrup, TE, Faber, TL, Folks, RD, Dim, UR, Mclaughlin, J, Pollepalle, D, Schapiro, W, Wang, Y, Akinboboye, O, Ngai, K, Druz, RS, Polepalle, D, Phippen-Nater, B, Leonardis, J, and Druz, R

Published
2004
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13. Poster display I clinical general

Author

Gurgenyan, S. V. Svetlana, Vatinyan, S. K. H., Nicogosyan, K. G., Edilyan, L. B., Chobanyan, B. G., Graf, S., Beheshti, M., Kienast, O., Oezer, S., Angelberger, P., Dudczak, R., Li, S. Shuren, Azevedo, J. C. Jader, Félix, R. C., Corrêa, P. L., Barbirato, G. B., Mesquita, E. T., Volschan, A., Dohmann, H. F., Mesquita, C. T., Peix, A. Amalia, Hidalgo, J., Dorticos, E., Llerena, L., Paredes, A., Macias, C., Valle, L. Del, Cortinas, L., Torres, M., Ponce, F., Petersen, C. L. Claus Leth, Appel, J., Kjaer, A., Awadalla, H. Hany, Hamed, R., Jamal, M., Rayan, M., Mahmoodi, A., Awaad, O., Demerdash, S. El, Adel, A., Kader, M. Abdel, Sarda-Mantel, L. Laure, Michel, J. B., Rouzet, F., Martet, G., Louedec, L., Raguin, O., Vrigneaud, J. M., Saumon, G., Khaw, B. A., Guludec, D. Le, Delahaye, N. Nicolas, Dinanian, S., Slama, M. S., Sarda, L., Tamas, C., Samuel, D., Adams, D., Syrota, A., Moralidis, E. Efstratios, Spyridonidis, T., Arsos, G., Karatzas, N., Karakatsanis, K., Koutelou, M. Maria, Theodorakos, A., Kollaros, N., Manginas, A., Graphakos, S., Tsapaki, V., Kouzoumi, A., Cokkinos, D., Goussetis, E., Prassopoulos, V. Vassilios, Parthenakis, F., Patrianakos, A., Velidaki, A., Koukouraki, S., Papadimitriou, E., Diakakis, G., Maurakis, H., Karakavitsas, N., Vardas, P., Koszegi, Z. Zsolt, Jenei, C., Varga, J., Galuska, L., Edes, I., Ray, Soumendranath, Kundu Bijon, Sarma S K., Day N R., Skouse, D. Douglas, Florimonte, L., Maffioli, L., Piatti, L., Calegari, M., Mancini, R., Bossi, M., Carboni, G. P. Gian Piero, Toriyama, T., Takase, H. Hiroyuki, Okado, T, Tanaka, S., Dohi, Y., Yasuhi, W. Watanabe, Akihiro, S., Akio, Y., Yasunori, W., Kimio, T., Nariaki, E., Yasuhiko, T., Ryo, K., Kasama, S. Shu, Honjo, T., Ichikawa, S., Toyama, T., Kurabayashi, M., Furuhashi, T. Tatsuhiko, Moroi, M., Kunimasa, T., Fukuda, H., Sugi, K., Takeishi, Y. Yasuchika, Arimoto, T., Kubota, I., Kambara, N. Naoshige, Hosokawa, R., Ohba, M., Saito, K., Motomura, H., Kanoi, T., Kume, N., Saji, H., Kita, T., Nohara, R., Akashi, Y. J. Yoshihiro, Musha, H., Kida, K., Suzuki, K., Inoue, K., Kawasaki, K., Hashimoto, N., Miyake, F., Yokoyama, Y. Yasuhiro, Sato, A., Nozato, T., Takahashi, A., Isobe, M., Aonuma, K., Hiroe, M., Peovska, I. Irena, Bosevski, M., Pavlovic, J.Maksimovic, Vavlukis, M., Vallejo, E. Enrique, Rodriguez, G., Jimenez, L., Hernandez, S., Bialostozky, D., Orea, A. Arturo, Asensio, E., Castillo, L., Dorantes, J., Narvaez, R., Gonzalez, O., Zee, P. M. Marc Van der, Verberne, H. J., Straalen, J. P. Van, Fischer, J. C., Sanders, G. T. B., Eck-Smit, B. L. F. Van, Winter, R. J. De, Kostkiewicz, M. Magdalena, Szot, W., Mura, A., Lesniak-Sobelga, A., Olszowska, M., Tracz, W., Ferreira, M. J. Maria Joao, Ferrer-Antunes, A. I., Rodrigues, V., Santos, F., Lima, J., Cerqueira, M. D., Providencia, L. A., Rodrigues, V., Martins, E., Vasconcelos, M. Mariana, Faria, T., Oliveira, A., Garcia, M., Pereira, J., Rocha-Goncalves, F., Lourenço, C. Cândida, Ferrer-Antunes, A., Vieira, H., Martins, R., Franco, F., Providência, L. A., Flotats, A. Albert, Estorch, M., Estorch, M. Montserrat, Mena, E., Camacho, V., Fuertes, J., Rodriguez, A., Flotats, A., Hernandez, M. A., Kulisewsky, J., Carrio, I., Jose-Galcera, J., Caballero-Martínez, A., Jara-Perez, P., Villegas-Garcia, M., Iñigo-García, L., Rosa, J. A. Nuño de la, Florenciano-Sánchez, R., Castillo-Soria, J. F., Valentí-Aldeguer, J. A., Pico-Aracil, F., Martínez-Caballero, A., Villegas-García, M., Castillo-Soria, F., Sánchez-Villanueva, J. G., Rosa, J. A. Nuço de la, Içigo-García, L., Palop, R., Florenciano-Sanchez, R., Lopez-Martínez, I., Jara-Pñrez, P., Rosa, J. A. Nuno de la, Castillo-Soria, F. J., Jara-Pérez, P., Contreras, J., Villegas-Sánchez, M., Obrador, D., Puig, M., Serra-Grima, R., Santaló, M., Carrió, I., Sorensen, J. Jens, Frostfeldt, G., Lindahl, B., Valind, S., Wallentin, L., Somsen, G. A. Aernout, Burri, H., Zaza, S., Fleury, E., Righetti, A., Entok, E. Emre, Birdane, A., Cavusoglu, Y., Ak, I., Timuralp, B., Haworth, M. J., Mitchell, A. R. J. Andrew, Gardner, M. A., Ormerod, O. J. M., Clements, I. P. Ian, Mullan, B. P., MacGregor, C. G., Breen, J. F., Akinboboye, O. O., Nichols, K. J., Wang, Y., Dim, U. Uzodinma, Lachman, J., Nichols, K. J., Muratore, K. A., Aracely, N., Haag, E. S., Druz, R. S. Regina, Gopal, A. S., Borges, A., Ngai, K. C., Dim, U. R., Wiley, M., Freeman, J., Kitchen, S., Graham, D., Schindel, M., Clark, E., Speiser, D., Hackney, T., Feldkamp, M., and Rosamond, T. Thomas

Published
2005
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15. Towards the definition of Institutional diagnostic reference levels in paediatric interventional cardiology procedures in Greece

Author

Kottou, S. Kollaros, N. Plemmenos, C. Mastorakou, I. Apostolopoulou, S.C. Tsapaki, V.

Abstract

This study aimed to evaluate paediatric radiation doses in a dedicated cardiology hospital, with the objective of characterising patterns in dose variation. The ultimate purpose was to define Local (Institutional) Diagnostic Reference Levels (LDRLs) for different types of paediatric cardiac interventional procedures (IC), according to patient age. From a total of 710 cases performed during three consecutive years, by operators with more than 15 years of experience, the age was noted in only 477 IC procedures. The median values obtained for Fluoroscopy Time (FT), Number of Frames (N) and Kerma Area Product (PKA) by age range were 5.8 min, 1322 and 2.0 Gy.cm2 for

Published
2018

16. PET and molecular imaging oral abstract session

Author

Levkau, B., Hermann, S. Sven, Baba, H., Stegger, L., Flögel, U., Schrader, J., Schäfers, K., Schober, O., Schäfers, M., Koutelou, M. Maria, Kollaros, N., Theodorakos, A., Manginas, A., Peristeri, I., Tsapaki, V., Kouzoumi, A., Cokkinos, D., Hosokawa, R. Ryohei, Ohba, M., Kambara, N., Tadamura, E., Kimura, T., Nohara, R., Kita, T., Panjrath, G. S. Gurusher, Patel, V., Narula, N., Narula, J., Jain, D., Dobrucki, L. W. Wawrzyniec, Lindsey, M. L., Song, J., Escobar, G. P., Su, H., Bourke, B., Mendizabal, M., Spinale, F. G., Sinusas, A. J., Herrero, P. Pilar, Kisrieva-Ware, Z., Dence, C. S., Coggan, A. R., Eisenbeis, P., Scott, S. R. W., Welch, M. J., and Gropler, R. J.

Published
2005
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19. Level of patient and operator dose in the largest cardiac centre in Greece

Author

Tsapaki, V. Patsilinakos, S. Voudris, V. Magginas, A. Pavlidis, S. Maounis, T. Theodorakis, G. Koutelou, M. Vrantza, T. Nearchou, M. Nikolaki, N. Kollaros, N. Kyrozi, E. Kottou, S. Karaiskos, P. Neofotistou, E. Cokkinos, D.

Abstract

The objective of this study was to investigate the patient and staff doses in the most frequent interventional cardiology (IC) procedures performed in Onassio, the largest Cardiac Centre in Greece. Data were collected from three digital X-ray systems for 212 coronary angiographies, 203 percutaneous transluminal coronary angioplasties (PTCA) and 134 various electrophysiological studies. Patient skin dose was measured using suitably calibrated slow radiotherapy films and cardiologist dose using suitably calibrated thermoluminescent dosemeters placed on left arm, hand and foot. Patient median dose area product (DAP) (all examinations) ranged between 6.7 and 83.5 Gy cm2. Patient median skin dose in PTCA was 799 mGy (320-1660 mGy) and in RF ablation 160 mGy (35-1920 mGy). Median arm, hand and foot dose to the cardiologist were 12.6, 27 and 13 μSv, respectively, per procedure. The great range of radiation doses received by both patients and operators confirms the need for continuous monitoring of all IC techniques. © The Author 2008. Published by Oxford University Press. All rights reserved.

Published
2008

21. Comparison of a CCD and a flat-panel digital system in an Interventional Cardiology Laboratory

Author

Tsapaki, V. Kottou, S. Kollaros, N. Kyriakidis, Z. Neofotistou, V.

Abstract

We evaluated the performances of angiographic units equipped with a flat-panel (FP) detector and image intensifier (II) charge-coupled device (CCD) in the Interventional Cardiology (IC) Department. Entrance dose rate and dose per image, along with the dose at the II level were measured using 2 mm copper sheets to simulate a patient. Image quality (IQ) was evaluated using a phantom. Doses increased with fluoroscopy level changing from low to high. FP presented higher doses than CCD. Periodic measurements showed differences of up to 35%. Low mode IQ did not significantly differ from normal and high mode for both systems. Low fluoroscopy mode was decided to be used routinely. Both X-ray systems performed within international recommendations for conventional systems with the exception of higher cine radiation doses and II dose rates, stressing the fact that more studies are required to investigate whether dose levels should be adjusted. © 2006 Oxford University Press.

Published
2006

22. Factors that influence radiation dose in percutaneous coronary intervention

Author

Tsapaki, V. Magginas, A. Vano, E. Kottou, S. Papadakis, E. Dafnomili, P. Kyrozi, E. Kollaros, N. Neofotistou, V. Cokkinos, D.

Abstract

Aim: To explore the factors that may influence the radiation dose imparted to the patient in PCI, and investigate whether the use of the latest digital X-ray system based on FP detector technology can have an impact on dose. Materials and Method: Demographic and clinical data such as number of lesions treated, number of stents placed, grade of tortuosity, and stage of occlusion, as well as use of double wire and double balloon technique, ostial stenting or bifurcation stenting, and presence of major complications were recorded, together with radiation parameters. Results: The factors that increased patient radiation dose were (1) patient gender, as men exhibited higher doses than women; (2) complex lesion; (3) increasing number of stents; (4) position of stent; (5) grade of tortuosity; and (6) stage of occlusion. The FP digital system appeared to be settled in a lower-dose rate for fluoroscopy (a factor of 6) and higher for dose per frame in cine (a factor of 3) in comparison with the image intensifier (II) system. There was a marked reduction of DAP when the FP technology was introduced. Conclusion: More extensive studies should be performed in the future so as to further investigate the influence of the FP detector in IC. ©2006, the Authors.

Published
2006

23. Comparison of a conventional and a flat-panel digital system in interventional cardiology procedures

Author

Tsapaki, V Kottou, S Kollaros, N Dafnomili, P Koutelou, M Vano, E Neofotistou, V

Abstract

The purpose of the study was to analyse the technical characteristics of a newly installed flat-panel fluoroscopy (FPF) system in an interventional cardiology (IC) department and compare it with an older conventional system. A patient survey, was performed to investigate the radiation doses delivered by the X-ray systems. Finally, methods of technique optimization regarding the new digital system were investigated. Dose rates in all fluoroscopic and cine modes were measured and image quality assessed using a dedicated test tool. 200 patients were investigated, half using the conventional and half using the digital FPF system. Patient data collected were: sex, age, weight, height, dose-area product (DAP), fluoroscopy time (7) and total number of frames (T). Our results are: (1) Digital FPF system: high contrast resolution (HCR) is not affected by fluoroscopic mode, whereas low contrast resolution (LCR) is slightly decreased in the low mode. (2) The digital FPF system has 2.5 times better HCR than the conventional system, with 5 times lower dose in the fluoroscopy mode. (3) Median values of DAP, T and F, respectively, in coronary angiography (CA) are: 27.7 Gycm(2), 4.1 min and 876 for the digital and 39.3 Gycm(2), 5.3 min and 1600 for the conventional system. Median values for percutaneous transluminal coronary angioplasty (PTCA) are: 51.1 Gycm(2), 12.7 min and 1184 for the digital and 44.3 Gycm(2), 7.4 min and 1936 for the conventional system. Digital DAP in CA is reduced by 30%, suggesting that a dose reduction in the FPF system is possible. The results of the study concerning the FPF system lead to the conclusion that the lowest fluoroscopic mode and the lowest frame rate should be used in routine practice.

Published
2004

24. Dose performance evaluation of a charge coupled device and a flat-panel digital fluoroscopy system recently installed in an Interventional Cardiology laboratory

Author

Tsapaki, V. Kottou, S. Kollaros, N. Dafnomili, P. Kyriakidis, Z. Neofotistou, V.

Abstract

The purpose of the study was to evaluate the dose performance of a flat-panel (FP) and an image intensifier (II) charge coupled device (CCD) digital fluoroscopy X-ray systems newly installed in an Interventional Cardiology (IC) department. Filter entrance dose rate, detector dose rate (during fluoroscopy) and filter entrance dose per image were measured at 70 cm from the focus using 2 mm copper sheets to mimic normal size patient. Image quality was also evaluated. The patient dose survey included 277 patients, which had either a Coronary Angiography (CA) or a Percutaneous Transluminal Coronary Angioplasty (PTCA). Dose area product (DAP), fluoroscopy time (T) and total number of frames (F) values were also collected. The results showed that both systems performed within international recommendations with the exception of higher cine radiation doses, stressing the fact that neither specific protocols of measurement nor reference values for digital equipment were provided by the official bodies. © Oxford University Press 2004; all rights reserved.

Published
2004

26. Fetal dose evaluation during breast cancer radiotherapy

Author

Antypas, C Sandilos, P Kouvaris, J Balafouta, E Karinou, E Kollaros, N Vlahos, L

Abstract

Purpose: The aim of the work was to estimate the radiation dose delivered to the fetus in a pregnant patient irradiated for breast cancer. Methods and Materials: A 45-year woman was treated for left breast cancer using a 6 MV photon beam with two isocentric opposing tangential unwedged fields. Daily dose was 2.3 Gy at 95% isodose line given by two fields/day, 5 days/week. A total dose of 46 Gy was given in 20 fractions over a 4-week period. Pregnancy confirmed during the second therapeutic week. Treatment lasted between the second and sixth gestation week. Radiation dose to fetus was estimated from in vivo and phantom measurements using thermoluminescence dosimeters and an ionization chamber. In vivo measurements were performed by inserting either a catheter with TL dosimeters or ionization chamber into the patient’s rectum. Phantom measurements were performed by simulating the treatment conditions on an anthropomorphic phantom. Results: TLD measurements (in vivo and phantom) revealed fetal dose to be 0.085% of the tumor dose, corresponding to a cumulative fetal dose of 3.9 cGy for the entire treatment of 46 Gy. Chamber measurements (in vivo and phantom) revealed a fetal dose less than the TLD result: 0.079 and 0.083% of the tumor dose corresponding to cumulative fetal dose of 3.6 cGy and 3.8 cGy for in vivo and phantom measurement, respectively. Conclusions: It was concluded that the cumulative dose delivered to the unshielded fetus was 3.9 cGy for a 46 Gy total tumor dose. The estimated fetal dose is low compared to the total tumor dose given due to the early stage of pregnancy, the large distance between fundus-radiation field, and the fact that no wedges and/or lead blocks were used. No deterministic biological effects of radiation on the live-born embryo are expected. The lifetime risk for radiation-induced fatal cancer is higher than the normal incidence, but is considered as inconsequential. (C) 1998 Elsevier Science Inc.

Published
1998

27. Level of patient and operator dose in the largest cardiac centre in Greece

Author

Tsapaki, V., primary, Patsilinakos, S., additional, Voudris, V., additional, Magginas, A., additional, Pavlidis, S., additional, Maounis, T., additional, Theodorakis, G., additional, Koutelou, M., additional, Vrantza, T., additional, Nearchou, M., additional, Nikolaki, N., additional, Kollaros, N., additional, Kyrozi, E., additional, Kottou, S., additional, Karaiskos, P., additional, Neofotistou, E., additional, and Cokkinos, D., additional

Published
2008
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28. 4.38

Author

Koutelou, M., primary, Theodorakos, A., additional, Kostopoulou, A., additional, Theodorakis, G., additional, Kollaros, N., additional, Kyrozi, E., additional, Kouzoumi, A., additional, and Kitziri, S., additional

Published
2007
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40. 401 Evidence of adherence of radiolabeled selected bone marrow stem cells to the previously infarcted non-viable anterior myocardial segment after intracoronary administration

Author

Manginas, A., Koutelou, M., Leontiadis, E., Kollaros, N., Peristeri, I., Goussetus, E., Graphakos, S., Theodorakos, A., Karatasakis, G., and Cokkinos, D.V.

Subjects
BONE marrow cells, RADIOLABELED blood cells
Abstract

An abstract of the study "Evidence of adherence of radiolabeled selected bone marrow stem cells to the previously infarcted non-viable anterior myocardial segment after intracoronary administration," by A. Manginas and colleagues is presented.

Published
2004
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41. From 2D to 3D gamma passing rate tolerance and action limits for patient-specific quality assurance in volumetric-modulated arc therapy.

Author

Zarros C, Patatoukas G, Kollaros N, Chalkia M, Kougioumtzopoulou A, Kouloulias V, and Platoni K

Abstract

Background: Volumetric modulated arc therapy (VMAT) requires an accurate patient-specific quality assurance (PSQA) program. In clinical practice, this is usually performed using the γ-index and the two-dimensional gamma passing rate (2D %GP). A three-dimensional (3D) index incorporating the patient anatomy could be more useful for the 3D dose distribution verification., Purpose: The current study demonstrates a thorough investigation of VMAT PSQA treatment plans by examining the correlation between 3D Gamma passing rate (%GP) and 2D %GP. The aim was to establish the tolerance limits (TL) and action limits (AL) that could be adopted in clinical practice., Materials and Methods: PSQA was performed for 67 head and neck (H&N) and 69 prostate treatment plans, using an appropriate phantom and the γ-index method. The 3%/2  mm acceptance criterion was used. Treatment plans' 2D% GP and 3D %GP values were collected and correlated with individual 3D %GP values of planning target volume (PTV) and organs at risk (OARs). Institutional TL and AL of both 2D %GP and 3D %GP were established using 30 prostate and 30 H&N treatment plans, as per recommendations proposed by AAPM TG-218., Results: A moderate correlation was observed between 2D %GP and 3D %GP of the treatment plans. Τhe correlations demonstrated a stronger association for the 3D %GP than for the 2D %GP with respect to the 3D %GP of the individual structures considered. The TL for the 3D %GP (both plan and individual) and the plans' 2D %GP were generally more stringent, while the AL showed a wider range compared to the corresponding limits suggested by the TG-218 protocol for plan 2D %GP., Conclusions: Institution-specific 3D %GP as well as TL and AL for treatment plan, PTV and OARs could be incorporated in the PSQA procedure in synergy with the 2D evaluation, as they can provide a more-in-depth-view of the treatment quality., (© 2025 The Author(s). Journal of Applied Clinical Medical Physics published by Wiley Periodicals, LLC on behalf of The American Association of Physicists in Medicine.)

Published
2025
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42. Single- versus Multi-computed Tomography Simulation for High-dose-rate Postoperative Gynecological Intracavitary Brachytherapy.

Author

Douvara A, Kollaros N, Patatoukas G, Chalkia M, Kypraiou E, Trogkanis N, Kouloulias V, and Platoni K

Abstract

Introduction: This study aimed to investigate whether there is a dosimetric difference of implementing single instead of multi-computed tomography (CT) simulation treatment planning for high-dose-rate postoperative gynecological intracavitary brachytherapy (BT)., Materials and Methods: Eighty patients were registered in the study. They received three BT fractions of 7 Gy/week (three CTs, three original plans). The organs at risk (OAR), the rectal wall, and the clinical target volume (CTV) were delineated. The delivered doses for the 2cc of OARs (D 2cc ), 1cc of rectal wall (D 1cc ), as well as for the 90% and 100% of CTV volume (D CTV90% , D CTV100% ) were evaluated. To evaluate the values of the above parameters if the single-CT-simulation method has been chosen, the time of the first treatment plan was corrected for the decay and applied as the second and third CT, retrospectively, creating the next fractions (two revised plans)., Results: No statistically significant ( P > 0.05) differences were found between the original and revised plans for the OARs and CTV. However, for the single-CT-simulation method, it was noted that the dose constraints for the total rectal dose were exceeded in some cases (36.3%)., Conclusion: The fact that rectal dose constraints were exceeded in 1/3 of patients with the single-CT-simulation method is dosimetrically significant., Competing Interests: There are no conflicts of interest., (Copyright: © 2024 Journal of Medical Physics.)

Published
2024
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43. Dosimetric comparison and evaluation of two computational algorithms in VMAT treatment plans.

Author

Tsimpoukelli M, Patatoukas G, Chalkia M, Kollaros N, Kougioumtzopoulou A, Michaletou D, Kouloulias V, and Platoni K

Subjects
Humans, Radiotherapy Dosage, Radiotherapy Planning, Computer-Assisted methods, Radiometry methods, Algorithms, Radiotherapy, Intensity-Modulated methods
Abstract

Purpose: This study aimed to assess the accuracy and dosimetric impact of the Acuros XB (AXB) algorithm compared to the Anisotropic Analytical Algorithm (AAA) in two situations. First, simple phantom geometries were set and analyzed; moreover, volumetric modulated arc therapy (VMAT) clinical plans for Head & Neck and lung cases were calculated and compared., Methods: First, a phantom study was performed to compare the algorithms with radiochromic EBT3 film doses using one PMMA slab phantom and two others containing foam or air gap. Subsequently, a clinical study was conducted, including 20 Head & Neck and 15 lung cases irradiated with the VMAT technique. The treatment plans calculated by AXB and AAA were evaluated in terms of planning target volume (PTV) coverage (V 95% ), dose received by relevant organs at risk (OARs), and the impact of using AXB with a grid size of 1 mm. Finally, patient-specific quality assurance (PSQA) was performed and compared for 17 treatment plans., Results: Phantom dose calculations showed a better agreement of AXB with the film measurements. In the clinical study, AXB plans exhibited lower Conformity Index and PTV V 95% , higher maximum PTV dose, and lower mean and minimum PTV doses for all anatomical sites. The most notable differences were detected in regions of intense heterogeneity. AXB predicted lower doses for the OARs, while the calculation time with a grid size of 1 mm was remarkably higher. Regarding PSQA, although AAA was found to exhibit slightly higher gamma passing rates, the difference did not affect the AXB treatment plan quality., Conclusions: AXB demonstrated higher accuracy than AAA in dose calculations of both phantom and clinical conditions, specifically in interface regions, making it suitable for sites with large heterogeneities. Hence, such dosimetric differences between the two algorithms should always be considered in clinical practice., (© 2023 The Authors. Journal of Applied Clinical Medical Physics published by Wiley Periodicals, LLC on behalf of The American Association of Physicists in Medicine.)

Published
2023
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44. Implementation, Dosimetric Assessment, and Treatment Validation of Knowledge-Based Planning (KBP) Models in VMAT Head and Neck Radiation Oncology.

Author

Fanou AM, Patatoukas G, Chalkia M, Kollaros N, Kougioumtzopoulou A, Kouloulias V, and Platoni K

Abstract

The aim of this study was to evaluate knowledge-based treatment planning (KBP) models in terms of their dosimetry and deliverability and to investigate their clinical benefits. Three H&N KBP models were built utilizing RapidPlan™, based on the dose prescription, which is given according to the planning target volume (PTV). The training set for each model consisted of 43 clinically acceptable volumetric modulated arc therapy (VMAT) plans. Model quality was assessed and compared to the delivered treatment plans using the homogeneity index (HI), conformity index (CI), structure dose difference (PTV, organ at risk-OAR), monitor units, MU factor, and complexity index. Model deliverability was assessed through a patient-specific quality assurance (PSQA) gamma index-based analysis. The dosimetric assessment showed better OAR sparing for the RapidPlan™ plans and for the low- and high-risk PTV, and the HI, and CI were comparable between the clinical and RapidPlan™ plans, while for the intermediate-risk PTV, CI was better for clinical plans. The 2D gamma passing rates for RapidPlan™ plans were similar or better than the clinical ones using the 3%/3 mm gamma-index criterion. Monitor units, the MU factors, and complexity indices were found to be comparable between RapidPlan™ and the clinical plans. Knowledge-based treatment plans can be safely adapted into clinical routines, providing improved plan quality in a time efficient way while minimizing user variability.

Published
2023
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45. A step closer to automation: kilovoltage and Megavoltage Planar Imaging Quality Assurance, baseline, tolerance and action levels definition and exploration.

Author

Fanou AM, Kollaros N, Patatoukas G, Efstathopoulos E, and Platoni K

Subjects
Phantoms, Imaging, Automation, Software, Particle Accelerators
Abstract

Purpose: To establish automated quality assurance (QA) procedures for the kilovoltage (kV) and the Megavoltage (MV) imagers of two linear accelerators (LINACS) using a commercial software., Methods: SNC Machine™ phantoms and software were used and the baseline values, tolerance and action levels for various image quality parameters were defined. Scaling, spatial resolution, contrast, uniformity and noise were considered, explored and evaluated utilizing the appropriate phantoms and the accompanying software. kV and MV planar radiographic images, for 6MV and 10MV beams were obtained for each LINAC. For both kV and MV QA tasks, the baseline values for spatial resolution, contrast, uniformity and noise were defined., Results: Subsequent measurements performed were highly reproducible and within tolerance and action levels, while noise showed variations. The calculated tolerance and action levels for noise were looser compared to the other image quality metrics., Conclusions: An automated QA workflow of the kV and MV planar radiographic mode of LINAC imagers' was established and appears to be time effective., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Associazione Italiana di Fisica Medica e Sanitaria. Published by Elsevier Ltd. All rights reserved.)

Published
2023
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46. Implementation of TG-218 for patient-specific quality assurance tolerance and action limits determination: Gamma passing rate evaluation using 3DVH software.

Author

Stasinou D, Patatoukas G, Kollaros N, Diamantopoulos S, Kypraiou E, Kougioumtzopoulou A, Kouloulias V, Efstathopoulos E, and Platoni K

Subjects
Humans, Male, Quality Assurance, Health Care, Radiometry methods, Radiotherapy Dosage, Radiotherapy Planning, Computer-Assisted methods, Software, Prostatic Neoplasms radiotherapy, Radiotherapy, Intensity-Modulated methods
Abstract

Purpose: To determine the tolerance limit (TL) and action limit (AL) of gamma passing rates (%GP) for volumetric-modulated arc therapy (VMAT) patient-specific quality assurance (PSQA) according to the American Association of Physicists in Medicine (AAPM) Task Group (TG)-218 recommendations, and to comparatively evaluate the clinical relevance of 2D %GP and 3D %GP., Methods: PSQA was performed for 100 head and neck (H&N) and 73 prostate cancer VMAT treatment plans. Measurements were acquired using a cylindrical water equivalent phantom, hollow in the center, allowing measurements with homogeneous or heterogeneous inserts. The LINAC-delivered dose distributions were compared to those calculated from the treatment planning system through the gamma index. TL and AL were determined through the computation of two-dimensional (2D) %GP using the recommended acceptance criteria. Dose-volume histograms were reconstructed from the measurements using a commercially available software to detect the dosimetric errors (%DE) between the compared dose distributions. Utilizing the estimated dose on the patient anatomy, structure-specific %GP (3D %GP) were calculated. The 3D %GP were compared to the 2D %GP ones based on their correlation with the %DE. Each metric's sensitivity was determined through receiver operator characteristic analysis., Results: TL and AL were in concordance with the universal ones, regarding the prostate cancer cases, but were lower for the H&N cases. Evaluation of %DE did not deem the plans unacceptable. The 2D %GP and the 3D %GP did not differ significantly regarding their correlation with %DE. For prostate plans, %GP sensitivity was higher than for H&N cases., Conclusions: Determination of institutional-specific TL and AL allows the monitoring of the PSQA procedure, yet for plans close to the limits, clinically relevant metrics should be used before they are deemed unacceptable for the process to be of higher sensitivity and efficiency., (© 2022 American Association of Physicists in Medicine.)

Published
2022
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47. The Use of Genotoxicity Endpoints as Biomarkers of Low Dose Radiation Exposure in Interventional Cardiology.

Author

Habibi M, Karyofyllis PK, Nikolakopoulou A, Papagiannis P, Karaiskos P, Georgakilas AG, Hatzi VI, Malakos I, Kollaros N, Mastorakou I, Voudris V, and Terzoudi GI

Subjects
Adult, Biomarkers, DNA Damage, Dose-Response Relationship, Radiation, Histones genetics, Humans, Cardiology, Radiation Injuries
Abstract

The effect of the reportedly low ionizing radiation doses, such as those very often delivered to patients in interventional cardiology, remains ambiguous. As interventional cardiac procedures may have a significant impact on total collective effective dose, there are radiation protection concerns for patients and physicians regarding potential late health effects. Given that very low doses (<100 mSv) are expected to be delivered during these procedures, the purpose of this study was to assess the potency and suitability of current genotoxicity biomarkers to detect and quantitate biological effects essential for risk estimation in interventional cardiology. Specifically, the biomarkers γ-H2AX foci, dicentric chromosomes, and micronuclei, which underpin radiation-induced DNA damage, were studied in blood lymphocytes of 25 adult patients before and after interventional cardiac procedures. Even though the mean values of all patients as a group for all three endpoints tested show increased yields relative to baseline following medical exposure, our results demonstrate that only the γ-H2AX biomarker enables detection of statistically significant differences at the individual level ( p < 0.001) for almost all patients (91%). Furthermore, 24 h after exposure, residual γ-H2AX foci were still detectable in irradiated lymphocytes. Their decline was found to vary significantly among the individuals and the repair kinetics of γ-H2AX foci was found to range from 25 to 95.6% of their maximum values obtained., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Habibi, Karyofyllis, Nikolakopoulou, Papagiannis, Karaiskos, Georgakilas, Hatzi, Malakos, Kollaros, Mastorakou, Voudris and Terzoudi.)

Published
2021
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48. Bone marrow stem cell adherence into old anterior myocardial infarction: a scintigraphic study using Tl-201 and Tc-99m-HMPAO.

Author

Kollaros N, Theodorakos A, Manginas A, Kitziri E, Katsikis A, Cokkinos D, and Koutelou M

Subjects
Adult, Cell Adhesion, Female, Humans, Male, Middle Aged, Myocardium pathology, Necrosis, Retrospective Studies, Stem Cells diagnostic imaging, Time Factors, Bone Marrow Cells pathology, Myocardial Infarction diagnostic imaging, Myocardial Infarction pathology, Radionuclide Imaging methods, Stem Cells pathology, Technetium Tc 99m Exametazime, Thallium Radioisotopes
Abstract

Aim: The precise localization of bone marrow stem cells (SCs) into the necrotic tissue after intracoronary infusion (ICI) may be important for the therapeutic outcome. This study aims to examine the correlation between Tl-201 and Tc-99m-hexa-methyl-propylene-amine-oxime (HMPAO) images., Methods: Thirteen patients, aged 36-62 years, with an old, nonviable, anterior myocardial infarction (MI) and reduced myocardial contractility (LVEF <40%), underwent ICI of selected CD133(+) and CD133(neg)CD34(+) SCs. One hour after the ICI, SPECT imaging with Tc-99m-HMPAO was performed in all patients and the acquired images were compared with the images obtained during the initial imaging for demonstration of viability (myocardial perfusion imaging with pharmacologic stress and Tl-201). Furthermore, two fused bull's eye images of Tc-99m-HMPAO and Tl-201 rest reinjection were created in six patients and regions of interest were set on Tl-201 and Tc-99m-HMPAO bull's eye images., Results: The comparison of the two sets of images revealed an intense accumulation of the SCs in the infarcted area with absence of viability as assessed by Tl-201 reinjection images. In the subset of patients in whom fused bull's eye images were produced, the comparison demonstrated that the percentage of the infarcted area with SCs' adherence was 83.2 ± 17%., Conclusions: Tl-201 images are complementary with the respective Tc-99m-HMPAO ones, revealing a precise localization of SCs in the infarcted area. Tc-99m-HMPAO labeling of SCs is a reliable method for cell monitoring after ICI in nonviable myocardium after an anterior MI.

Published
2012
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49. Intracoronary infusion of CD133+ and CD133-CD34+ selected autologous bone marrow progenitor cells in patients with chronic ischemic cardiomyopathy: cell isolation, adherence to the infarcted area, and body distribution.

Author

Goussetis E, Manginas A, Koutelou M, Peristeri I, Theodosaki M, Kollaros N, Leontiadis E, Theodorakos A, Paterakis G, Karatasakis G, Cokkinos DV, and Graphakos S

Subjects
AC133 Antigen, Adult, Bone Marrow Cells immunology, Bone Marrow Transplantation methods, Chronic Disease, Flow Cytometry, Follow-Up Studies, Humans, Male, Middle Aged, Myocardial Ischemia pathology, Myocardium immunology, Myocardium pathology, Stem Cells immunology, Transplantation, Autologous, Antigens, CD immunology, Antigens, CD34 immunology, Bone Marrow Cells cytology, Glycoproteins immunology, Myocardial Ischemia surgery, Peptides immunology, Stem Cells cytology
Abstract

Central issues in intracoronary infusion (ICI) of bone marrow (BM)-cells to damaged myocardium for improving cardiac function are the cell number that is feasible and safe to be administrated as well as the retention of cells in the target area. Our study addressed these issues in eight patients with chronic ischemic cardiomyopathy undergoing ICI of selected BM-progenitors. We could immunomagnetically isolate 0.8 +/- 0.32 x 10(7) CD133(+) cells and 0.75 +/- 0.24 x 10(7) CD133(-)CD34(+) cells from 310 +/- 40 ml BM. After labeling these cells with (99m)Tc-hexamethylpropylenamineoxime, they were infused into the infarct-related artery without any complication. Scintigraphic images 1 (eight patients) and 24 hours (four patients) after ICI revealed an uptake of 9.2% +/- 3.6 and 6.8% +/- 2.4 of the total infused radioactivity in the infarcted area of the heart, respectively; the remaining activity was distributed mainly to liver and spleen. We conclude that through ICI of CD133(+) and CD133(-)CD34(+) BM-progenitors a significant number of them are preferentially attracted to and retained in the chronic ischemic myocardium.

Published
2006
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50. Factors that influence radiation dose in percutaneous coronary intervention.

Author

Tsapaki V, Magginas A, Vano E, Kottou S, Papadakis E, Dafnomili P, Kyrozi E, Kollaros N, Neofotistou V, and Cokkinos D

Subjects
Coronary Artery Disease therapy, Female, Fluoroscopy, Humans, Male, Middle Aged, Prospective Studies, Risk Assessment, Risk Factors, Angioplasty, Balloon, Coronary methods, Coronary Artery Disease radiotherapy, Radiation Dosage
Abstract

Aim: To explore the factors that may influence the radiation dose imparted to the patient in PCI, and investigate whether the use of the latest digital X-ray system based on FP detector technology can have an impact on dose., Materials and Method: Demographic and clinical data such as number of lesions treated, number of stents placed, grade of tortuosity, and stage of occlusion, as well as use of double wire and double balloon technique, ostial stenting or bifurcation stenting, and presence of major complications were recorded, together with radiation parameters., Results: The factors that increased patient radiation dose were (1) patient gender, as men exhibited higher doses than women; (2) complex lesion; (3) increasing number of stents; (4) position of stent; (5) grade of tortuosity; and (6) stage of occlusion. The FP digital system appeared to be settled in a lower-dose rate for fluoroscopy (a factor of 6) and higher for dose per frame in cine (a factor of 3) in comparison with the image intensifier (II) system. There was a marked reduction of DAP when the FP technology was introduced., Conclusion: More extensive studies should be performed in the future so as to further investigate the influence of the FP detector in IC.

Published
2006
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