Preclinical study investigating the potential of low-dose-rate brachytherapy with 32 P stents for the prevention of restenosis of paranasal neo-ostia.

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.