We use a wide field imaging Mueller polarimeter to visualize the fiber tracts of healthy brain in the retardance maps for the detection of tumor borders. The results of ex-vivo polarimetric studies of thick sections of brain tissue are presented.
The crucial problem of brain tumor surgery is the accurate detection the tumor border for safe and complete tumor resection. Whereas it is quite easy to identify brain tumor in preoperative magnetic resonance imaging, it is often difficult to differentiate solid tumor tissue from infiltrated white matter during surgery with conventional surgical intra-operative microscope. To address this problem we suggest exploring the optical anisotropy of healthy brain white matter which represents a highly ordered structure consisting of axons that are joined together in fiber tracts. Tumor cells grow chaotically and erase the optical anisotropy of healthy brain. Instead of detecting the tumor itself, we suggest to visualize healthy white matter by means of its fiber tracts by detecting the optical anisotropy of brain tissue. For this purpose we used a wide-field imaging Mueller polarimetric system operating in the visible wavelength range in backscattering configuration. The Mueller matrix images of the thick (~1cm) fixed human brain specimen and thick (~1cm) fresh veal brain specimen were measured at 633 nm in reflection. Lu Chipman decomposition was applied pixel-wise to the experimental Mueller matrices. The maps of azimuth of fast optical axis of linear birefringent medium showed a compelling correlation with the fiber tracts directions on histology image of thin whole mount silver-stained brain tissue section, that is gold standard for ex-vivo brain fiber tract visualization. Thus, label-free non-contact imaging Mueller polarimetry shows potential for the intra-operative visualization of brain white matter fiber tracts. Further studies are ongoing.
The accurate detection of brain tumor border during neurosurgery is crucial for the safe and complete tumor resection, but it is often difficult to differentiate solid tumor tissue from infiltrated white matter. To address this problem we suggest detecting optical anisotropy of brain white matter which consists of bundles of axons (or fiber tracts). Tumor growth erases this optical anisotropy of healthy brain. We used a wide-field imaging Mueller polarimeter to measure thick fixed human and fresh animal brain sections in reflection. The maps of azimuth of fast optical axis of linear birefringent medium obtained from Lu-Chipman decomposition of the experimental Mueller matrices showed a compelling correlation with the fiber tracts directions on histology image of thin whole mount silver-stained brain tissue section.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.