Ex vivo Visualization of Human Gliomas with Cross-Polarization Optical Coherence Tomography: Pilot Study
Optical coherence tomography (OCT) is a promising method of optical diagnostics in neurosurgery. This paper presents the initial results of using cross-polarization OCT (CP OCT) for the visualization of glioma tissue. CP OCT can detect the scattering and polarization properties of tissues and thereby provide more information about their structure than traditional OCT. The aim of the study was to evaluate the capabilities of CP OCT as an imaging tool for the visualization of glial tumors with different degrees of malignancy. Materials and Methods. The study was performed on material obtained from the intraoperative biopsies (ex vivo specimens) of 18 patients with gliomas ranging from Grade I to Grade IV. Seventy nine samples of tumor and non-tumor tissue were studied using the CP OCT device developed the Institute of Applied Physics of the Russian Academy of Sciences (Nizhny Novgorod, Russia). 361 CP OCT images were acquired and analyzed. They were compared with histological data seen in sections coincident with the planes of the OCT scans. Results. The correspondence between the CP OCT images of human brain tissue and glial tumors and their morphological features was determined. A comparative evaluation of the characteristics of the CP OCT signals of glial tumors Grade I-IV and non-cancerous brain tissue was carried out. Conclusion. The morphological features of white matter and glial tumors can be differentiated based on the intensity, homogeneity and attenuation of the CP OCT signals. The use of high-speed spectral CP OCT device appears to have great potential in the neurosurgery practice.