15 July 2015 Optical spectroscopy for stereotactic biopsy of brain tumors
Author Affiliations +
Stereotactic biopsy procedure is performed to obtain a tissue sample for diagnosis purposes. Currently, a fiber-based mechano-optical device for stereotactic biopsies of brain tumors is developed. Two different fluorophores are employed to improve the safety and reliability of this procedure: The fluorescence of intravenously applied indocyanine green (ICG) facilitates the recognition of blood vessels and thus helps minimize the risk of cerebral hemorrhages. 5- aminolevulinic-acid-induced protoporphyrin IX (PpIX) fluorescence is used to localize vital tumor tissue. ICG fluorescence detection using a 2-fiber probe turned out to be an applicable method to recognize blood vessels about 1.5 mm ahead of the fiber tip during a brain tumor biopsy. Moreover, the suitability of two different PpIX excitation wavelengths regarding practical aspects was investigated: While PpIX excitation in the violet region (at 405 nm) allows for higher sensitivity, red excitation (at 633 nm) is noticeably superior with regard to blood layers obscuring the fluorescence signal. Contact measurements on brain simulating agar phantoms demonstrated that a typical blood coverage of the tumor reduces the PpIX signal to about 75% and nearly 0% for 633 nm and 405 nm excitation, respectively. As a result, 633 nm seems to be the wavelength of choice for PpIX-assisted detection of high-grade gliomas in stereotactic biopsy.
© (2015) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Niklas Markwardt, Niklas Markwardt, Anna von Berg, Anna von Berg, Sebastian Fiedler, Sebastian Fiedler, Marcus Goetz, Marcus Goetz, Neda Haj-Hosseini, Neda Haj-Hosseini, Christoph Polzer, Christoph Polzer, Herbert Stepp, Herbert Stepp, Petr Zelenkov, Petr Zelenkov, Adrian Rühm, Adrian Rühm, } "Optical spectroscopy for stereotactic biopsy of brain tumors", Proc. SPIE 9542, Medical Laser Applications and Laser-Tissue Interactions VII, 954208 (15 July 2015); doi: 10.1117/12.2183741; https://doi.org/10.1117/12.2183741

Back to Top