Local physiological changes during photodynamic therapy.
نویسنده
چکیده
BACKGROUND AND OBJECTIVE Herein an overview is provided of the causes, consequences, and significance of photodynamic therapy (PDT)-mediated effects on tumor oxygenation and blood flow during illumination. STUDY DESIGN/MATERIALS AND METHODS Techniques particularly valuable to this research have included tissue oxygen tension measurement by the Eppendorf pO2 Histograph; spatial quantification of hypoxia by EF3 and EF5; and tissue oxygenation/blood flow monitoring by diffuse reflectance/correlation spectroscopy. RESULTS Severe hypoxia was measured in vivo during PDT and is shown to be a consequence of photochemical oxygen consumption and/or compromised vascular perfusion. Oxygen depletion can be controlled by treatment regimen, occurs in a spatially-definable pattern, and is therapy-limiting. PDT-induced changes in tumor oxygenation during illumination are correlated with outcome. In PDT-treated tissues, blood flow also is determined by treatment regimen and correlates with treatment response. CONCLUSIONS Photodynamic therapy creates distinct, measurable changes in tumor oxygen and blood flow during illumination. These physiological changes may ultimately affect treatment efficacy.
منابع مشابه
Photodynamic Therapy: A New Approach to Remove Embryos of the Wistar Rat
Background Photodynamic therapy (PDT) is a promising new cancer treatment strategy which inactivates tumor cells by simultaneoulsy using light and a photosensitizer. The similarity between tumors and newly implanted embryos is notable. Extrauterine pregnancy (EUP) does not have a definite treatment and previous therapeutic options (medical and surgical) have not been effective or suitable. Ther...
متن کاملIn vivo measurement of parameters of dosimetric importance during interstitial photodynamic therapy of thick skin tumors.
A system for interstitial photodynamic therapy is used in the treatment of thick skin tumors. The system allows simultaneous measurements of light fluence rate, sensitizer fluorescence, and tissue oxygen saturation by using the same fibers as for therapeutic light delivery. Results from ten tumor treatments using delta-aminolevulinic acid (ALA)-induced protoporphyrin IX show a significant, trea...
متن کاملClinical system for interstitial photodynamic therapy with combined on-line dosimetry measurements.
A system for interstitial photodynamic therapy with delta-aminolaevulinic acid and multiple optical fibers has been developed. The system enables photodynamic treatment of large embedded tumor volumes and utilizes real-time measurements to allow on-line dosimetry. Important parameters such as light fluence rate, sensitizer fluorescence intensity, and changes in local blood oxygen saturation are...
متن کاملPhotodynamic Inactivation of Endopathogenic Microbiota Using Curcumin- mediated Antimicrobial Photodynamic Therapy
Root canal disinfection is one of the main factors governing success of endodontic therapy. Antimicrobial photodynamic therapy (aPDT) is presented as a promising antimicrobial therapy that can eliminate microbiota present in infected root canal systems. In this study, a series of experiments investigated the effects of aPDT on cell viability and biofilm degradation ability of endopathogenic mic...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- Lasers in surgery and medicine
دوره 38 5 شماره
صفحات -
تاریخ انتشار 2006