Presentation
14 August 2019 Dosimetry recommendations for NMIBC: a simulation and in vivo study (Conference Presentation)
Lothar D. Lilge, Daniel Molehuis, Angelica Manalac, Fynn Schwiegelshohn, Vaughn Betz, Wayne Embree, Arkady Mandel, Roger Dumont-White, Girish Kulkani, Michael Jewett
Author Affiliations +
Proceedings Volume 11070, 17th International Photodynamic Association World Congress; 110704S (2019) https://doi.org/10.1117/12.2526079
Event: 17th International Photodynamic Association World Congress, 2019, Cambridge, Massachusetts, United States
Abstract
Recurrent Non-Muscle Invasive Bladder Cancer (NMIBC) is a diffuse disease, and patients have failed standard BCG therapy face prophylactic cystectomy. PDT fell out of favour due to its variable outcome, and high morbidity. To overcome PDT associate toxicity to the bladder’s muscle layer, the use of shorter wavelength and instillation of the photosensitizer were suggested. While either approach was shown to improve the outcome in animal models they have not previously combined in human studies. Additionally, the effects of highly variable tissue optical properties of the bladder and its shape have not been studied. Here, we present surface dose histograms derived from light propagation simulation in 6 human bladders using CT images for anatomical detail and the FullMonte software package. The ability of a single light sensor versus 3 or 12 light sensors to measure the average irradiance on the bladder surface was evaluated as a function of the bladder wall’s tissue optical properties. Results show that the irradiance in non-spherical bladders can vary over an order of magnitude, but the irradiance histograms are affected little by displacement of the emitter inside the bladder void. As the surface area monitored by a single sensor depends strongly on the bladder shape, the responsivity of a single sensor to the average bladder irradiance can vary equally. Twelve light sensors monitor the entire bladder surface almost complete and hence their average responsivity is constant to the average irradiance on the bladder largely independent of shape. The dependency of the sensor’s response on the tissue optical properties is also lower.
Conference Presentation
© (2019) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Lothar D. Lilge, Daniel Molehuis, Angelica Manalac, Fynn Schwiegelshohn, Vaughn Betz, Wayne Embree, Arkady Mandel, Roger Dumont-White, Girish Kulkani, and Michael Jewett "Dosimetry recommendations for NMIBC: a simulation and in vivo study (Conference Presentation)", Proc. SPIE 11070, 17th International Photodynamic Association World Congress, 110704S (14 August 2019); https://doi.org/10.1117/12.2526079
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KEYWORDS
Bladder

In vivo imaging

Natural surfaces

Optical properties

Optical sensors

Sensors

Tissue optics

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