gms | German Medical Science

67. Jahrestagung der Deutschen Gesellschaft für Neurochirurgie (DGNC)
Joint Meeting mit der Koreanischen Gesellschaft für Neurochirurgie (KNS)

Deutsche Gesellschaft für Neurochirurgie (DGNC) e. V.

12. - 15. Juni 2016, Frankfurt am Main

CARS microscopy for the detection of infiltrating glioblastoma in native tissue samples

Meeting Abstract

  • Ortrud Uckermann - Klinik und Poliklinik für Neurochirugurgie, Universitätsklinikum Carl Gustav Carus an der TU Dresden, Dresden, Germany
  • Roberta Galli - Klinisches Sensoring und Monitoring, Klinik für Anesthesiologie und Intensivtherapie, Universitätsklinikum Carl Gustav Carus an der TU Dresden, Dresden, Germany
  • Gabriele Schackert - Klinik und Poliklinik für Neurochirugurgie, Universitätsklinikum Carl Gustav Carus an der TU Dresden, Dresden, Germany
  • Gerald Steiner - Klinisches Sensoring und Monitoring, Klinik für Anesthesiologie und Intensivtherapie, Universitätsklinikum Carl Gustav Carus an der TU Dresden, Dresden, Germany
  • Matthias Kirsch - Klinik und Poliklinik für Neurochirugurgie, Universitätsklinikum Carl Gustav Carus an der TU Dresden, Dresden, Germany

Deutsche Gesellschaft für Neurochirurgie. 67. Jahrestagung der Deutschen Gesellschaft für Neurochirurgie (DGNC), 1. Joint Meeting mit der Koreanischen Gesellschaft für Neurochirurgie (KNS). Frankfurt am Main, 12.-15.06.2016. Düsseldorf: German Medical Science GMS Publishing House; 2016. DocMI.22.02

doi: 10.3205/16dgnc371, urn:nbn:de:0183-16dgnc3713

Veröffentlicht: 8. Juni 2016

© 2016 Uckermann et al.
Dieser Artikel ist ein Open-Access-Artikel und steht unter den Lizenzbedingungen der Creative Commons Attribution 4.0 License (Namensnennung). Lizenz-Angaben siehe http://creativecommons.org/licenses/by/4.0/.


Gliederung

Text

Objective: Coherent anti-Stokes Raman scattering (CARS) microscopy holds great prospect for label-free medical imaging. Based on their low lipid content, it enables delineation of brain tumors. However, tumor identification on bulk samples and in vivo has been so far verified retrospectively on histological sections, which only provides a gross reference without matching at cellular level. Therefore, fluorescent labels were exploited for the interpretation of CARS images of solid and infiltrative tumors.

Method: Glioblastoma cells (U87) expressing green fluorescent protein (GFP) were used for induction of tumors in mice (n = 7) and CARS images were acquired on native brain slices and in vivo using a cranial window approach. The neoplastic nature of cells was confirmed by addressing two-photon fluorescence of GFP. In native biopsies of human glioblastoma (n = 8), the fluorescence of 5-aminolevulinic acid-induced protoporphyrin IX was used for identification of tumorous tissue prior to CARS imaging. Image analysis was performed to extract distinctive features of tumor cells.

Results: Addressing the GPF fluorescence in vital brain slices enabled to locate large tumors as well as single infiltrating tumor cells. All tumors were characterized by a significant reduction of CARS signal intensity to 0.73 ± 0.14 (P=0.0156) compared to gray matter. On slices and in vivo, we were able to match even single tumor cells to dark areas in the CARS images demonstrating that the chemical contrast provided by CARS allows the identification of small infiltrations. Furthermore, we identified distinctive morphological parameters of glioblastoma cells in the CARS images of both mouse and human brain tumors. Cell nuclei were significantly enlarged (nuclear area mouse gray matter: 34 ± 13 µm2 vs. experimental tumor: 89 ± 22, P< 0,0001; human GBM: 77 ±19 µm2), the nuclear membrane was clearly discerned and the nucleolus was well defined.

Conclusions: These findings constitute an important step for the reliable recognition of brain neoplastic structures in CARS images that is necessary for the future application as intraoperative technique. For glioblastoma, both CARS signal intensity and cell morphology constitute objective parameters that allow discerning normal and neoplastic tissue structures, down to the level of single infiltrating tumor cells on native tissue and in vivo. In the future, a similar study should be dedicated to other types of brain tumors, with a special attention to metastases.