Zsolt Cselik

Publications (5)9.87 Total impact

• Article: Impact of infrared laser light-induced ablation at different wavelengths on bovine intervertebral disc ex vivo: evaluation with magnetic resonance imaging and histology.

  Zsolt Cselik, Mihály Aradi, Ronald A von Jako, Zsuzsanna Lelovics, Ivett Juhász, Zsolt Egyházi, Péter Bogner, Imre Repa, Attila Schwarcz
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  ABSTRACT: Percutaneous laser disc decompression is commonly used to lower high pressure in the nucleus pulposus in degenerative disc diseases. The aim of this study was to investigate the impact of diode laser disc decompression at different wavelengths (980-nm vs. 1,470-nm, i.e., different water absorption characteristics). To model decompression, a flexible laser quartz fiber inserted into the nucleus pulposus of ex vivo bovine spines using computer-assisted surgical navigation was utilized to vaporize tissue. The same energy (500 J) was delivered using both 980-nm and 1,470-nm wavelength lasers. To determine the different impact of the wavelengths before and after the procedure we evaluated the discs with MRI (T(1), T(2), diffusion maps) and with histopathology. There were no visible changes on T(1) and T(2) maps after 1,470-nm wavelength laser irradiation; however, the 980-nm wavelength caused significant changes on T(1) (decrease) and T(2) (increase) in the vaporization zone at the site of the quartz fiber. Pathological findings showed carbonization and steam-bubble formation in addition to the T(1) and T(2) changes. No significant changes were detected in the value of apparent diffusion coefficient (ADC) measurements in intervertebral disc with the 980-nm wavelength, but significant ADC and T(1) signal increase was detected with the 1,470-nm wavelength when the whole nucleus pulposus was considered. The 1,470-nm laser light had an effect in the whole nucleus pulposus and not only at the site of the quartz fiber, whereas with the 980-nm laser irradiation, significant changes were demonstrated only at the application site.
  Lasers in Surgery and Medicine 04/2012; 44(5):406-12. · 2.75 Impact Factor
• Article: Thermoplastic patient fixation: influence on chest wall and target motion during radiotherapy of lung cancer.

  Arpad Kovacs, Janaki Hadjiev, Ferenc Lakosi, Marta Vallyon, Zsolt Cselik, Peter Bogner, Akos Horvath, Imre Repa
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  ABSTRACT: Several methods have been developed to reduce tumor motions and patient movements during radiotherapy of lung cancer. In this study, a multislice CT-based analysis was performed to examine the effect of a thermoplastic patient immobilization system on the chest wall and tumor motions. Ten patients with stage II-IV lung cancer were enrolled into the study. According to tumor localization, five patients had peripheral, and five patients central lung cancer (T2-T4). In total, six series of measurements were made with a multislice CT scanner, both with and without mask fixation, in normal breathing, at maximal tidal volume inhalation, and at maximal tidal volume exhalation. Movements of chest wall, diaphragm and tumor, with and without mask, under different breathing conditions were registered. With the use of the immobilization system, no significant difference was found in diaphragmatic movements (mean deviation of diaphragm: 41.7-40.5 mm to the right, and 40.5-36.8 mm to the left side) and in tumor motions (mean deviation of tumor: 15.3-12.4 mm in craniocaudal, and 11.5-8.8 mm in posterolateral direction, mean medial deviation: 4.6-4.1 mm, mean lateral deviation: 7.2-5 mm). Significant differences were observed concerning tumor motions in anteroposterior direction (mean: 8.9-6.3 mm) and transverse chest movements in anteroposterior direction. Besides the advantage of optimal patient positioning, the movements of the bony chest wall can be considerably reduced by using the immobilization system. However, this fixation system has limitations concerning its suitability for minimizing tumor motions.
  Strahlentherapie und Onkologie 06/2007; 183(5):271-8. · 3.56 Impact Factor
• Article: Thermoplastic Patient Fixation

  Arpad Kovacs, Janaki Hadjiev, Ferenc Lakosi, Marta Vallyon, Zsolt Cselik, Peter Bogner, Akos Horvath, Imre Repa
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  ABSTRACT: Background and Purpose:Several methods have been developed to reduce tumor motions and patient movements during radiotherapy of lung cancer. In this study, a multislice CT-based analysis was performed to examine the effect of a thermoplastic patient immobilization system on the chest wall and tumor motions. Patients and Methods:Ten patients with stage II–IV lung cancer were enrolled into the study. According to tumor localization, five patients had peripheral, and five patients central lung cancer (T2–T4). In total, six series of measurements were made with a multislice CT scanner, both with and without mask fixation, in normal breathing, at maximal tidal volume inhalation, and at maximal tidal volume exhalation. Results:Movements of chest wall, diaphragm and tumor, with and without mask, under different breathing conditions were registered. With the use of the immobilization system, no significant difference was found in diaphragmatic movements (mean deviation of diaphragm: 41.7–40.5 mm to the right, and 40.5–36.8 mm to the left side) and in tumor motions (mean deviation of tumor: 15.3–12.4 mm in craniocaudal, and 11.5–8.8 mm in posterolateral direction, mean medial deviation: 4.6–4.1 mm, mean lateral deviation: 7.2–5 mm). Significant differences were observed concerning tumor motions in anteroposterior direction (mean: 8.9–6.3 mm) and transverse chest movements in anteroposterior direction. Conclusion:Besides the advantage of optimal patient positioning, the movements of the bony chest wall can be considerably reduced by using the immobilization system. However, this fixation system has limitations concerning its suitability for minimizing tumor motions. Hintergrund und Ziel:Zahlreiche Methoden wurden entwickelt, um die Tumor- und Patientenbewegungen während der Strahlentherapie von Lungenkarzinomen zu reduzieren. In dieser Studie wurde eine Mehrschicht-CT-basierte Analyse zur Untersuchung der Auswirkungen eines thermoplastischen Patientenimmobilisierungssystems auf die Thoraxwand- und Tumorbewegungen durchgeführt. Patienten und Methodik:Zehn Patienten mit Lungenkrebs Stadium II–IV wurden in die Studie eingeschlossen. Gemäß der Tumorlokalisation wiesen fünf Patienten ein peripheres und fünf Patienten ein zentrales Lungenkarzinom auf (T2–T4). Insgesamt wurden sechs Messserien mit einem Mehrschicht-CT-Scanner durchgeführt: mit und ohne Maskenfixierung, bei normaler Atmung sowie mit maximalem Atemvolumen bei Ein- und Ausatmung. Ergebnisse:Die Brustwand-, Zwerchfell- und Tumorbewegungen wurden mit und ohne Maske bei unterschiedlichen Atmungszuständen registriert. Bei Verwendung des Immobilisierungssystems wurden keine signifikanten Unterschiede in den Zwerchfellbewegungen (durchschnittliche Abweichung des Diaphragmas: 41,7–40,5 mm nach links und 40,5–36,8 mm nach rechts) und den Tumorbewegungen (durchschnittliche Abweichung des Tumors: 15,3–12,4 mm in kraniokaudaler und 11,5–8,8 mm in posteroanteriorer Richtung, durchschnittliche mediale Abweichung: 4,6–4,1 mm, durchschnittliche laterale Abweichung 7,2–5 mm) festgestellt. Signifikante Unterschiede waren bezüglich der Tumorbewegungen in anteroposteriorer Richtung (durchschnittlich 8,9–6,3 mm) und der transversalen Brustkorbbewegungen in anteroposteriorer Richtung zu beobachten. Schlussfolgerung:Neben dem Vorteil einer optimalen Patientenpositionierung können die Bewegungen der Thoraxwand mit Hilfe des Immobilisierungssystems erheblich reduziert werden. Dieses Fixierungssystem hat jedoch auch Grenzen hinsichtlich seiner Eignung zur Minimierung der Tumorbewegungen.
  Strahlentherapie und Onkologie 04/2007; 183(5):271-278. · 3.56 Impact Factor
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  Available from: nb.rs

  Article: Application of mri for improved local control in complex radiotherapy of cervical cancer

  Janaki Hadjiev, Zsolt Cselik, Péter Bogner, Árpád Kovács, Ferenc Lakosi, Gyula Kotek, Imre Repa
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  ABSTRACT: Background: The aim of this study was to analyze the use of magnetic resonance imaging (MRI) as a modern medical imaging technique in radiotherapy with special emphasis on the integration of MRI and a novel technique in brachytherapy to optimize treatment outcome in cervical cancer. Methods: In addition to the CT based shrinking volume conformal teletherapy in 31 patients with locally advanced cervical cancer, MRI examination with a special adjustable applicator at the treatment site was performed for the brachytherapy planning. To avoid excessive doses to the healthy structures during complex cervical radiotherapy isodose curves were calculated upon the information of the MR image and dose distribution was evaluated. Results: The consecutive application of CT and MRI limited the possibility for overdosage of the critical organs and undertreatment of the advanced tumor spread in all cases. The overall response rate for the complex treatment was 74.2% with complete regression in 25.8% of the cases. Based on the exact information of the three dimensional digital data radiation doses could be optimized without increasing the possibility of acute complications rate. Conclusion: The introduction of 3D treatment planning for teletherapy pelvic and boost irradiation of cervical carcinoma as well as for the brachytherapy part of the complex treatment is to be recommended. .
  Archive of Oncology. 01/2006;
• Article: Az individuális sugárérzékenység szerepe és jelentősége a sugárterápiában = Role and significance of individual radiosensitivity in radiation oncology

  Olga Ésik, Zsolt Cselik, Beatrix Farkas, Katalin Hideghéty, Gábor Horváth, Örs Péter Horváth, Zsuzsanna Kahán, Eniko Kis, Árpád Kovács, Ferenc Lakosi, Géza Sáfrány
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  ABSTRACT: Betegek 1. Bőr-biopsiás mintákból nyert fibroblast (Fb)-kultúrákban a survival fraction at 2 Gy (SF2)-értékek meghatározása 93 betegben. A radiogén második tumor relatív kockázatának (RR) becslése 6, 0-IA stádiumú, méhnyakrákos betegben. 2. A génexpresszió vizsgálata 7 normális, illetve 3 fokozottan sugárérzékeny sejtvonalban. 3. Multisegmentális (MS) besugárzás tanulmányozása 436 emlőrákbetegnél. Eredmények 1. Az akut dermatitis/mucositis 8/14 (57%), a reirradiáció 1/6, a késői idegrendszeri károsodás 4/11 (36%), a késői kötőszöveti/bőr toxicitás 9/50 (18%) beteg esetében járt együtt fokozott Fb-sugárérzékenységgel. A sugárkezelt, korai méhnyakrákos betegek RR-je rectumtumorra 9, anusrákra 23. 2. A normális sugárérzékenységű Fb-kből származó RNS-ekben a besugárzás hatására 109 gén expressziója növekedett, és 115 gén működése csökkent; fokozott sugárérzékenység esetén a hasonló adatok 142, illetve 56. 3. MS tervezéssel a tervezési céltérfogat (TCT) 90,9%-a esett a kívánatos dózisértékek közé (hagyományos tervezéssel: 82,8%), s a normális szervek dózisterhelése nem növekedett. Konklúziók 1. Nagyobb gyakorisággal alakulnak ki radiogén sérülések olyan betegekben, akik Fb-jének fokozott a sugárérzékenysége. 2. A sugárérzékenység sugárterápia előtti meghatározása elősegíthetné az egyénre szabott terápiás protokollok kialakítását. 3. Az MS sugárkezelés a normális szövetek dózis-terhelésének növekedése nélkül javítja a TCT dózisellátottságát. | Patients 1. Survival fractions at 2 Gy (SF2s) were determined using skin biopsy-based fibroblast (Fb) cultures in 93 pts. The relative risks (RRs) of radiogenic, secondary cancer were determined for 6, stage 0-IA, radiotherapy?treated cervix cancer pts. 2. Gene expressions were analyzed for 7 normal and 3 radiosensitive Fb cell lines. 3. Multisegmental (MS) radiotherapy was investigated in 436 breast cancer pts. Results 1. Inreased radiosensitivity was detected in 8/14 (57%) pts with acute dermatitis/mucositis, in 1/6 pts before reirradiation, in 4/11 (36%) pts with late neurological sequelae, and 9/50 (18%) pts with late subcutaneus/cutaneous toxicity. For radiotherapy-treated, early cervical cancer pts, the RRs are 9 and 23 to develope rectal and anal cancer, respectively. 2. Expressions of 109 genes were increased and 115 of them were decreased following irradiation of normal Fbs, while the comparative results for radiation-sensitive Fbs were 142 and 56, respectively. 3. Using MS radiotherapy, 90,9% of the planning target volme (PTV) was covered by the prescribed dose without an increase of radiation burden on normal tissues. Conclusions 1. The probability of radiation sequelae is higher among pts with radiosensitive Fbs. 2. Identification of radiosensitivity would help to determine individualized therapy protocols. 3. Introduction of MS radiotherapy would improve the PTV coverage without increasing the radiation burden on normal tissues.