AI Article Synopsis
- Researchers aimed to prevent bladder symptoms like urgency, frequency, and pain that can result from bladder photodynamic therapy (PDT) by exploring different light intensity levels during treatment.
- The study involved testing two different fluence rates (high and low) on rats with bladder tumors and examining the resulting tissue for inflammation and cell death.
- Results indicated that while high fluence rates caused damage and inflammation, low fluence rates effectively treated tumors with fewer side effects, preserving normal bladder tissue integrity.
Article Abstract
Purpose: We studied how to avoid irritative bladder symptoms after bladder photodynamic therapy, such as urgency, frequency and pain, which are associated with the inflammation and destruction of normal urothelium.
Materials And Methods: Rats bearing orthotopic bladder tumors were instilled with hexyl-aminolevulinate and illuminated with red light at a high vs low (100 vs 15 mW/cm(2)) fluence rate. Cystectomy specimens 48 hours after treatment were subjected to anatomopathological examination. Inflammatory reaction and apoptosis were evaluated. In vivo photobleaching was assessed during illumination at each fluence rate.
Results: All superficial tumors were eradicated irrespective of light dose and fluence rate. High fluence rates induced necrosis with inflammatory reaction and absent normal urothelium. Low fluence rates did not provoke inflammation and resulted in apoptotic cell death with preserved urothelial integrity. This could be attributable to faster photobleaching of the photosensitizer in normal urothelium at low fluence rates.
Conclusions: Bladder photodynamic therapy at a low fluence rate minimizes side effects without hampering therapeutic efficacy.
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| http://dx.doi.org/10.1016/j.juro.2013.01.046 | DOI Listing |
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