In vivo photosensitizer tomography inside the human prostate.

Interstitial photodynamic therapy (IPDT) provides a promising means to treat large cancerous tumors and solid organs inside the human body. The treatment outcome is dependent on the distributions of light, photosensitizer, and tissue oxygenation. We present a scheme for reconstructing the spatial distribution of a fluorescent photosensitizer. The reconstruction is based on measurements performed in the human prostate, acquired during an ongoing IPDT clinical trial, as well as in optical phantoms. We show that in an experimental setup we can quantitatively reconstruct a fluorescent inclusion in a fluorescent background. We also show reconstructions from a patient showing a heterogeneous distribution of the photosensitizer mTHPC in the human prostate.

[1]  S. Arridge Optical tomography in medical imaging , 1999 .

[2]  M Emberton,et al.  Photodynamic therapy using meso tetra hydroxy phenyl chlorin (mTHPC) in early prostate cancer , 2006, Lasers in surgery and medicine.

[3]  S B Malkowicz,et al.  Preliminary results of interstitial motexafin lutetium‐mediated PDT for prostate cancer , 2006, Lasers in surgery and medicine.

[4]  Jarod C Finlay,et al.  Interstitial Fluorescence Spectroscopy in the Human Prostate During Motexafin Lutetium–Mediated Photodynamic Therapy , 2006, Photochemistry and photobiology.

[5]  Stefan Andersson-Engels,et al.  Clinical system for interstitial photodynamic therapy with combined on-line dosimetry measurements. , 2005, Applied optics.

[6]  Brian C. Wilson,et al.  Techniques for delivery and monitoring of TOOKAD (WST09)-mediated photodynamic therapy of the prostate: clinical experience and practicalities. , 2005 .

[7]  M. Altschuler,et al.  Optimized interstitial PDT prostate treatment planning with the Cimmino feasibility algorithm. , 2005, Medical physics.

[8]  L. Lilge,et al.  Implicit and explicit dosimetry in photodynamic therapy: a New paradigm , 1997, Lasers in Medical Science.

[9]  Stefan Andersson-Engels,et al.  Improved accuracy in time-resolved diffuse reflectance spectroscopy. , 2008, Optics express.

[10]  Tayyaba Hasan,et al.  Pretreatment photosensitizer dosimetry reduces variation in tumor response. , 2006, International journal of radiation oncology, biology, physics.

[11]  K. H. Drexhage,et al.  Fluorescence quantum yield of oxazine and carbazine laser dyes , 1981 .

[12]  Stefan Andersson-Engels,et al.  Spatially varying regularization based on spectrally resolved fluorescence emission in fluorescence molecular tomography. , 2007, Optics express.

[13]  Johannes Swartling,et al.  Realtime light dosimetry software tools for interstitial photodynamic therapy of the human prostate. , 2007, Medical physics.

[14]  Per Christian Hansen,et al.  REGULARIZATION TOOLS: A Matlab package for analysis and solution of discrete ill-posed problems , 1994, Numerical Algorithms.

[15]  B. Pogue,et al.  Weight-matrix structured regularization provides optimal generalized least-squares estimate in diffuse optical tomography. , 2007, Medical physics.

[16]  R. Weissleder,et al.  Experimental three-dimensional fluorescence reconstruction of diffuse media by use of a normalized Born approximation. , 2001, Optics letters.