Non-invasive intraoperative optical coherence tomography of the resection cavity during surgery of intrinsic brain tumors

Abstract

Optical coherence tomography (OCT) is a non-invasive imaging technique with a micrometer resolution. It allows noncontact / non-invasive analysis of central nervous system tissues with a penetration depth of 1-3,5 mm reaching a spatial resolution of approximately 4-15 µm. We have adapted spectral-domain OCT (SD-OCT) and time-domain OCT (TD-OCT) for intraoperative detection of residual tumor during brain tumor surgery. Human brain tumor tissue and areas of the resection cavity were analyzed during the resection of gliomas using this new technology. The site of analysis was registered using a neuronavigation system and biopsies were taken and submitted to routine histology. We have used post image acquisition processing to compensate for movements of the brain and to realign A-scan images for calculation of a light attenuation factor. OCT imaging of normal cortex and white matter showed a typical light attenuation profile. Tumor tissue depending on the cellularity of the specimen showed a loss of the normal light attenuation profile resulting in altered light attenuation coefficients compared to normal brain. Based on this parameter and the microstructure of the tumor tissue, which was entirely absent in normal tissue, OCT analysis allowed the discrimination of normal brain tissue, invaded brain, solid tumor tissue, and necrosis. Following macroscopically complete resections OCT analysis of the resection cavity displayed the typical microstructure and light attenuation profile of tumor tissue in some specimens, which in routine histology contained microscopic residual tumor tissue. We have demonstrated that this technology may be applied to the intraoperative detection of residual tumor during resection of human gliomas.

Current trends in intraoperative optical imaging for functional brain mapping and delineation of lesions of language cortex

“…Another technique, optical coherence tomography (OCT) (Chen et al, 1999) has also recently been demonstrated to intraoperatively distinguish white matter and gray matter and potentially distinguish tumor from normal tissue within glioma resection cavities (Giese et al, 2006). Both 5AL imaging and OCT may be compatible with iOIS to allow essentially simultaneous, functional mapping and tumor delineation.…”

“…For example, laser speckle imaging (LSI) has excellent spatiotemporal resolution for surface imaging of CBF (Briers, 2001; Dunn et al, 2001; Liu et al, 2005). OCT (Giese et al, 2006) and optical Doppler tomography (ODT) (Chen et al, 1999) have exquisite three-dimensional spatial resolution. OCT has recently been validated for intraoperative detection of residual tumor during resection of human gliomas (Giese et al, 2006).…”

“…OCT (Giese et al, 2006) and optical Doppler tomography (ODT) (Chen et al, 1999) have exquisite three-dimensional spatial resolution. OCT has recently been validated for intraoperative detection of residual tumor during resection of human gliomas (Giese et al, 2006). …”

High-resolution wide-field human brain tumor margin detection and in vivo murine neuroimaging

“…However, maximal safe resection is often limited by an inability to distinguish tumor from normal brain. To address this problem, a variety of intraoperative imaging modalities have been investigated, including magnetic resonance imaging (MRI) [12][13][14][15] , wide-field fluorescence 7 , highresolution fluorescence microscopy (confocal and multiphoton imaging) 16 , and optical coherence tomography (OCT) [17][18][19][20][21] .…”

Optical coherence tomography for precision brain imaging, neurosurgical guidance and minimally invasive theranostics

“…Giese et al reported that tumorous tissues of human brain and areas of the resection cavity were analyzed during the resection of gliomas within OCT guidance (80). Recently, excellent research reported by Kut et al investigated a self-regulating OCT system on ex vivo human tissue specimens of 32 patients (81), and the method to discriminate between normal and tumorous tissues is based on the optical attenuation coefficient measured by developing nanoparticle-based OCT imaging contrast agents during operation (82,83).…”