Elmar Oestreicher1, Harald Bartsch2, Doris Mayr2, Mario Schubert3, Barbara Weber1, Peter Kneschaurek4, Walter Assmann3, Ronald Sroka5, Christian Stephan Betz6. 1. Department of Otorhinolaryngology, Klinikum Rechts der Isar, Technische Universität München, Munich, Germany. 2. Institute of Pathology, Ludwig Maximilian University, Munich, Germany. 3. Department of Medical Physics, Ludwig Maximilian University, Garching, Germany. 4. Department of Radiotherapy and Radiation Oncology, Klinikum Rechts der Isar, Technische Universität München, Munich, Germany. 5. Laser Research Laboratory, LIFE Centre, Klinikum der Universität München, Munich, Germany; Department of Urology, Klinikum der Universität München, Munich, Germany. 6. Laser Research Laboratory, LIFE Centre, Klinikum der Universität München, Munich, Germany; Department of Otorhinolaryngology, Klinikum der Universität München, Munich, Germany. Electronic address: christian.betz@med.uni-muenchen.de.
Abstract
PURPOSE: Ostial restenosis is a common cause of failures in paranasal sinus surgery. The aim of the current study was to investigate the use of low-dose-rate brachytherapy to prevent neo-ostial restenosis in an animal model. METHODS AND MATERIALS: In 14 rabbits, maxillary neo-ostia were created and measured. One side each was stented with a regular silicone stent, the other side was either not stented (n = 7) or stented with a phosphorous-32 implanted stent depositing a low-dose radiation of 15 Gy (n = 7) within 1 week, after which all stents were removed. After a period of additional 12 weeks of recovery, the animals were sacrificed, the neo-ostia were again measured, and the areas and histopathologic changes compared in between the groups. RESULTS: After 15-Gy stenting, the mean ostial areas were even slightly enlarged by 5.1% compared to the area at stent removal, whereas a significant reduction in area, indicating a process of restenosis, by 56.1% or 54.0% was seen in the control groups with no stent and normal stent, respectively. Furthermore, no indication for adverse histopathologic radiation effects was seen in the 15-Gy group. CONCLUSIONS: Low-dose-rate brachytherapy with phosphorous-32 doped silicone stents showed promising results in the prevention of neo-ostium restenosis in this proof-of-concept study, indicating that further preclinical and clinical testing may be warranted.
PURPOSE: Ostial restenosis is a common cause of failures in paranasal sinus surgery. The aim of the current study was to investigate the use of low-dose-rate brachytherapy to prevent neo-ostial restenosis in an animal model. METHODS AND MATERIALS: In 14 rabbits, maxillary neo-ostia were created and measured. One side each was stented with a regular silicone stent, the other side was either not stented (n = 7) or stented with a phosphorous-32 implanted stent depositing a low-dose radiation of 15 Gy (n = 7) within 1 week, after which all stents were removed. After a period of additional 12 weeks of recovery, the animals were sacrificed, the neo-ostia were again measured, and the areas and histopathologic changes compared in between the groups. RESULTS: After 15-Gy stenting, the mean ostial areas were even slightly enlarged by 5.1% compared to the area at stent removal, whereas a significant reduction in area, indicating a process of restenosis, by 56.1% or 54.0% was seen in the control groups with no stent and normal stent, respectively. Furthermore, no indication for adverse histopathologic radiation effects was seen in the 15-Gy group. CONCLUSIONS: Low-dose-rate brachytherapy with phosphorous-32 doped silicone stents showed promising results in the prevention of neo-ostium restenosis in this proof-of-concept study, indicating that further preclinical and clinical testing may be warranted.