How tissue optics affect dosimetry of photodynamic therapy

被引:59
作者
Jacques, Steven L. [1 ,2 ]
机构
[1] Oregon Hlth & Sci Univ, Dept Dermatol, Portland, OR 97239 USA
[2] Oregon Hlth & Sci Univ, Dept Biomed Engn, Portland, OR 97239 USA
关键词
photodynamic therapy; dosimetry; tissue optics; optical properties; PROSTATE;
D O I
10.1117/1.3494561
中图分类号
Q5 [生物化学];
学科分类号
071010 ; 081704 ;
摘要
We describe three lessons learned about how tissue optics affect the dosimetry of red to near-infrared treatment light during PDT, based on working with Dr. Tayyaba Hasan. Lesson 1-The optical fluence rate phi near the tissue surface exceeds the delivered irradiance (E). A broad beam penetrates into tissue to a depth (z) as phi = Eke(-mu z), with an attenuation constant mu and a backscatter term k. In tissues, k is typically in the range 3-5, and 1/mu equals delta, the 1/e optical penetration depth. Lesson 2-Edge losses at the periphery of a uniform treatment beam extend about 3 delta from the beam edge. If the beam diameter exceeds 6 delta, then there is a central zone of uniform fluence rate in the tissue. Lesson 3-The depth of treatment is linearly proportional to delta (and the melanin content of pigmented epidermis in skin) while proportional to the logarithm of all other factors, such as irradiance, exposure time, or the photosensitizer properties (concentration, extinction coefficient, quantum yield for oxidizing species). The lessons illustrate how tissue optics play a dominant role in specifying the treatment zone during PDT. (C) 2010 Society of Photo-Optical Instrumentation Engineers. [DOI: 10.1117/1.3494561]
引用
收藏
页数:6
相关论文
共 10 条
[1]   Treatment planning and dose analysis for interstitial photodynamic therapy of prostate cancer [J].
Davidson, Sean R. H. ;
Weersink, Robert A. ;
Haider, Masoom A. ;
Gertner, Mark R. ;
Bogaards, Arjen ;
Giewercer, David ;
Scherz, Avigdor ;
Sherar, Michael D. ;
Elhilali, Mostafa ;
Chin, Joseph L. ;
Trachtenberg, John ;
Wilson, Brian C. .
PHYSICS IN MEDICINE AND BIOLOGY, 2009, 54 (08) :2293-2313
[2]  
HASAN T, 1994, SPIE SHORT COURSE NO
[3]  
Jacques S. L., 1999, DIFFUSE REFLECTANCE
[4]  
JACQUES SL, 1992, P SOC PHOTO-OPT INS, V1645, P155, DOI 10.1117/12.60938
[5]   THE MELANOSOME - THRESHOLD TEMPERATURE FOR EXPLOSIVE VAPORIZATION AND INTERNAL ABSORPTION-COEFFICIENT DURING PULSED LASER IRRADIATION [J].
JACQUES, SL ;
MCAULIFFE, DJ .
PHOTOCHEMISTRY AND PHOTOBIOLOGY, 1991, 53 (06) :769-775
[6]   Realtime light dosimetry software tools for interstitial photodynamic therapy of the human prostate [J].
Johansson, Ann ;
Axelsson, Johan ;
Andersson-Engels, Stefan ;
Swartling, Johannes .
MEDICAL PHYSICS, 2007, 34 (11) :4309-4321
[7]   Effect of surface roughness on determination of bulk tissue optical parameters [J].
Ma, XY ;
Lu, JQ ;
Hu, XH .
OPTICS LETTERS, 2003, 28 (22) :2204-2206
[8]  
MARIJNISSEN J P A, 1987, Lasers in Medical Science, V2, P235, DOI 10.1007/BF02594166
[9]   INVIVO TESTS OF THE CONCEPT OF PHOTODYNAMIC THRESHOLD DOSE IN NORMAL RAT-LIVER PHOTOSENSITIZED BY ALUMINUM CHLOROSULFONATED PHTHALOCYANINE [J].
PATTERSON, MS ;
WILSON, BC ;
GRAFF, R .
PHOTOCHEMISTRY AND PHOTOBIOLOGY, 1990, 51 (03) :343-349
[10]   MCML - MONTE-CARLO MODELING OF LIGHT TRANSPORT IN MULTILAYERED TISSUES [J].
WANG, LH ;
JACQUES, SL ;
ZHENG, LQ .
COMPUTER METHODS AND PROGRAMS IN BIOMEDICINE, 1995, 47 (02) :131-146