305 Speckle-Free and Large Gold Nanorod Enhanced Optical Coherence Tomography for Brain Tumor Margin Detection

Neurosurgery ◽  
2017 ◽  
Vol 64 (CN_suppl_1) ◽  
pp. 264-264 ◽  
Author(s):  
Derek W Yecies ◽  
Orly Liba ◽  
Elliot SoRelle ◽  
Rebecca Dutta ◽  
Christy Wilson ◽  
...  
Keyword(s):  
Optical Coherence Tomography ◽  
Brain Tumor ◽  
Ex Vivo ◽  
Cellular Level ◽  
Large Field ◽  
Optical Coherence ◽  
Tumor Margin ◽  
Oct Imaging ◽  
Margin Detection

Abstract INTRODUCTION Optical coherence tomography (OCT) is an emerging technology with the potential to allow for rapid intraoperative detection of brain tumor margins by detecting differences in structure, intensity, spectral signal, and attenuation. OCT systems are capable of rapid imaging of large three-dimensional volumes with cellular level resolution. However, OCT imaging has previously been limited by speckle artifact and the lack of suitable contrast agents, limitations that are surmounted in this study. METHODS We prepared nude mice with orthotopic U87 glioblastoma xenografts and glass cranial windows. We also created large gold nanorods (LGNR) with plasmonic peaks tuned to the spectral range of the OCT scanner. LGNRs were injected intravenously into tumor-bearing mice and OCT imaging was performed in vivo utilizing a novel method for the removal of speckle artifact called Speckle-Free OCT (SFOCT). Fresh ex-vivo patient samples were also imaged. RESULTS >OCT and SFOCT readily distinguished tumor from normal brain with cellular level spatial resolution and to a depth of 1.5 mm. Additionally, SFOCT allowed for the highest resolution ever seen in vivo of mouse white matter architecture. Cortical layers were also readily visible in SFOCT in both live mice and in the ex-vivo human samples, representing a novel ability to interrogate cortical cytoarchitecture across a large field of view. Systemically administered LGNRs were tumor specific and provided excellent spectral contrast using OCT. Ex-vivo hyperspectral and IHC imaging confirmed the localization of LGNRs within the tumor and found that the LGNRs were largely localized within tumor associated macrophages. CONCLUSION SFOCT and LGNR enhanced OCT imaging are promising state of the art technologies for intraoperative tumor margin detection.

scholarly journals Neuroendovascular Optical Coherence Tomography Imaging and Histological Analysis

Neurosurgery ◽  
2011 ◽  
Vol 69 (2) ◽  
pp. 430-439 ◽  
Author(s):  
Marlon S. Mathews ◽  
Jianping Su ◽  
Esmaeil Heidari ◽  
Elad I. Levy ◽  
Mark E. Linskey ◽  
...  
Keyword(s):  
Optical Coherence Tomography ◽  
High Resolution ◽  
Carotid Arteries ◽  
Ex Vivo ◽  
Infrared Light ◽  
Optical Coherence ◽  
The Common ◽  
Oct Imaging ◽  
Common Carotid Arteries

Abstract BACKGROUND: Intravascular optical coherence tomography (OCT) is a recently developed optical imaging technique that provides high-resolution cross-sectional in situ images from intact tissue based on tissue reflectance of near-infrared or infrared light. OBJECTIVE: To report on the feasibility of neuroendovascular OCT imaging and compare the neuroendovascular OCT findings with histology in nondiseased vessels in an animal, cadaveric, and clinical study. METHODS: Catheter-based in vivo endovascular OCT imaging was performed in the common carotid arteries of 2 pigs and in the intracranial carotid arteries of 3 patients. The endovascular OCT device was delivered to the desired location via groin access and using standard endovascular procedures. Images were obtained via rotational and translational scanning using external motors. In vivo findings were reproduced using ex vivo OCT imaging in corresponding animal and human (cadaveric) harvested tissue segments. These segments underwent histological examination for comparison. RESULTS: The structural compositions of the OCT-imaged segments of the common carotid arteries in pigs as well as the petrous and cavernous intracranial carotid arteries in patients were visualized at high resolution (8 μm). The in vivo images were identical to those obtained ex vivo, demonstrating the imaging capabilities of the endovascular OCT device. The OCT images correlated well with the images obtained after histological sectioning and visualized in vivo the laminar vascular structure. CONCLUSION: Neuroendovascular OCT imaging is feasible for clinical use and can detect with high resolution the structure of arterial segments. Understanding OCT imaging in nondiseased arteries is important in establishing baseline findings necessary for interpreting pathological processes. This allows neuroendovascular optical biopsies of vascular tissue to be obtained without the need for excision and processing.

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

2018 ◽  
Author(s):  
Derek Yecies ◽  
Orly Liba ◽  
Elliott SoRelle ◽  
Rebecca Dutta ◽  
Edwin Yuan ◽  
...  
Keyword(s):  
Brain Tumor ◽  
White Matter ◽  
Ex Vivo ◽  
Field Of View ◽  
Low Grade ◽  
Wide Field ◽  
Tumor Margin ◽  
Wide Field Of View ◽  
Margin Detection

AbstractCurrent in vivo neuroimaging techniques provide limited field of view or spatial resolution and often require exogenous contrast. These limitations prohibit detailed structural imaging across wide fields of view and hinder intraoperative tumor margin detection. Here we present a novel neuroimaging technique, speckle-modulating optical coherence tomography (SM-OCT), which allows us to image the brains of live mice and ex vivo human samples with unprecedented resolution and wide field of view using only endogenous contrast. The increased effective resolution provided by speckle elimination reveals white matter fascicles and cortical layer architecture in the brains of live mice. To our knowledge, the data reported herein represents the highest resolution imaging of murine white matter structure achieved in vivo across a wide field of view of several millimeters. When applied to an orthotopic murine glioblastoma xenograft model, SM-OCT readily identifies brain tumor margins with near single-cell resolution. SM-OCT of ex vivo human temporal lobe tissue reveals fine structures including cortical layers and myelinated axons. Finally, when applied to an ex vivo sample of a low-grade glioma resection margin, SM-OCT is able to resolve the brain tumor margin. Based on these findings, SM-OCT represents a novel approach for intraoperative tumor margin detection and in vivo neuroimaging.

scholarly journals Morpho-molecular ex vivo detection and grading of non-muscle-invasive bladder cancer using forward imaging probe based multimodal optical coherence tomography and Raman spectroscopy

The Analyst ◽  
2020 ◽  
Vol 145 (4) ◽  
pp. 1445-1456 ◽  
Author(s):  
Fabian Placzek ◽  
Eliana Cordero Bautista ◽  
Simon Kretschmer ◽  
Lara M. Wurster ◽  
Florian Knorr ◽  
...  
Keyword(s):  
Raman Spectroscopy ◽  
Optical Coherence Tomography ◽  
Imaging System ◽  
Ex Vivo ◽  
Large Field ◽  
Optical Coherence ◽  
Fiber Optic Probe ◽  
Optic Probe ◽  
Muscle Invasive

Characterization of bladder biopsies, using a combined fiber optic probe-based optical coherence tomography and Raman spectroscopy imaging system that allows a large field-of-view imaging and detection and grading of cancerous bladder lesions.

Ex Vivo assessment of competent strut coverage after coronary stenting by optical coherence tomography

2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
R Bhoite ◽  
H Jinnouchi ◽  
F Otsuka ◽  
Y Sato ◽  
A Sakamoto ◽  
...  
Keyword(s):  
Optical Coherence Tomography ◽  
Predictive Value ◽  
Ex Vivo ◽  
High Sensitivity ◽  
Optical Coherence ◽  
Cross Sectional ◽  
Neointimal Thickness ◽  
Stent Strut ◽  
Oct Imaging ◽  
Definition Of

Abstract Background In many studies, struts coverage is defined as >0 mm of tissue overlying the stent struts by optical coherence tomography (OCT). However, this definition has never been validated using histology as the “gold standard”. The present study sought to assess the appropriate cut-off value of neointimal thickness of stent strut coverage by OCT using histology. Methods OCT imaging was performed on 39 human coronary arteries with stents from 25 patients at autopsy. A total of 165 cross-sectional images from 46 stents were co-registered with histology. The optimal cut-off value of strut coverage by OCT was determined. Strut coverage by histology was defined as endothelial cells with at least underlying two layers of smooth muscle cells. Considering the resolution of OCT is 10–20 μm, 3 different cut-off values (i.e. at ≥20, ≥40, and ≥60 μm) were assessed. Results A total of 2235 struts were evaluated by histology. Eventually, 1216 struts which were well-matched struts were analyzed in this study. By histology, uncovered struts were observed in 160 struts and covered struts were observed in 1056 struts. The broadly used definition of OCT-coverage which does not consider neointimal thickness yielded a poor specificity of 37.5% and high sensitivity 100%. Of 3 cut-off values, the cut-off value of >40 μm was more accurate as compared to >20 and >60 mm [sensitivity (99.3%), specificity (91.0%), positive predictive value (98.6%), and negative predictive value (95.6%)] Conclusion The most accurate cut-off value was ≥40 μm neointimal thickness by OCT in order to identify stent strut coverage validated by histology. Funding Acknowledgement Type of funding source: None

scholarly journals Polarization sensitive optical coherence tomography with single input for imaging depth-resolved collagen organizations

2021 ◽  
Vol 10 (1) ◽  
Author(s):  
Peijun Tang ◽  
Mitchell A. Kirby ◽  
Nhan Le ◽  
Yuandong Li ◽  
Nicole Zeinstra ◽  
...  
Keyword(s):  
Optical Coherence Tomography ◽  
Structural Integrity ◽  
Ex Vivo ◽  
Polarization State ◽  
Transmission Model ◽  
Optical Coherence ◽  
Healthy Human ◽  
Collagen Organization ◽  
Single Input

AbstractCollagen organization plays an important role in maintaining structural integrity and determining tissue function. Polarization-sensitive optical coherence tomography (PSOCT) is a promising noninvasive three-dimensional imaging tool for mapping collagen organization in vivo. While PSOCT systems with multiple polarization inputs have demonstrated the ability to visualize depth-resolved collagen organization, systems, which use a single input polarization state have not yet demonstrated sufficient reconstruction quality. Herein we describe a PSOCT based polarization state transmission model that reveals the depth-dependent polarization state evolution of light backscattered within a birefringent sample. Based on this model, we propose a polarization state tracing method that relies on a discrete differential geometric analysis of the evolution of the polarization state in depth along the Poincare sphere for depth-resolved birefringent imaging using only one single input polarization state. We demonstrate the ability of this method to visualize depth-resolved myocardial architecture in both healthy and infarcted rodent hearts (ex vivo) and collagen structures responsible for skin tension lines at various anatomical locations on the face of a healthy human volunteer (in vivo).

scholarly journals Imaging depth extension of optical coherence tomography in rabbit eyes using optical clearing agents

2020 ◽  
Vol 245 (18) ◽  
pp. 1629-1636
Author(s):  
Ruiming Kong ◽  
Wenjuan Wu ◽  
Rui Qiu ◽  
Lei Gao ◽  
Fengxian Du ◽  
...  
Keyword(s):  
Optical Coherence Tomography ◽  
Ex Vivo ◽  
Light Attenuation ◽  
Anterior Segment ◽  
Posterior Segment ◽  
Glycerol Solution ◽  
Optical Coherence ◽  
Optical Clearing ◽  
Imaging Depth

Optical coherence tomography has become an indispensable diagnostic tool in ophthalmology for imaging the retina and the anterior segment of the eye. However, the imaging depth of optical coherence tomography is limited by light attenuation in tissues due to optical scattering and absorption. In this study of rabbit eye both ex vivo and in vivo, optical coherence tomography imaging depth of the anterior and posterior segments of the eye was extended by using optical clearing agents to reduce multiple scattering. The sclera, the iris, and the ciliary body were clearly visualized by direct application of glycerol at an incision on the conjunctiva, and the posterior boundary of sclera and even the deeper tissues were detected by submerging the posterior segment of eye in glycerol solution ex vivo or by retro-bulbar injection of glycerol in vivo. The ex vivo rabbit eyes recovered to their original state in 60 s after saline-wash treatment, and normal optical coherence tomography images of the posterior segment of the sample eyes proved the self-recovery of in vivo performance. Signal intensities of optical coherence tomography images obtained before and after glycerol treatment were compared to analysis of the effect of optical clearing. To the best of our knowledge, this is the first study for imaging depth extension of optical coherence tomography in both the anterior and posterior segments of eye by using optical clearing agents.

scholarly journals In Xenopus ependymal cilia drive embryonic CSF circulation and brain development independently of cardiac pulsatile forces

2020 ◽  
Vol 17 (1) ◽  
Author(s):  
A. H. Dur ◽  
T. Tang ◽  
S. Viviano ◽  
A. Sekuri ◽  
H. R. Willsey ◽  
...  
Keyword(s):  
Optical Coherence Tomography ◽  
Brain Development ◽  
Neural Cell ◽  
Optical Coherence ◽  
Csf Flow ◽  
Csf Circulation ◽  
Cell Organization ◽  
Ependymal Cilia ◽  
Oct Imaging

Abstract Background Hydrocephalus, the pathological expansion of the cerebrospinal fluid (CSF)-filled cerebral ventricles, is a common, deadly disease. In the adult, cardiac and respiratory forces are the main drivers of CSF flow within the brain ventricular system to remove waste and deliver nutrients. In contrast, the mechanics and functions of CSF circulation in the embryonic brain are poorly understood. This is primarily due to the lack of model systems and imaging technology to study these early time points. Here, we studied embryos of the vertebrate Xenopus with optical coherence tomography (OCT) imaging to investigate in vivo ventricular and neural development during the onset of CSF circulation. Methods Optical coherence tomography (OCT), a cross-sectional imaging modality, was used to study developing Xenopus tadpole brains and to dynamically detect in vivo ventricular morphology and CSF circulation in real-time, at micrometer resolution. The effects of immobilizing cilia and cardiac ablation were investigated. Results In Xenopus, using OCT imaging, we demonstrated that ventriculogenesis can be tracked throughout development until the beginning of metamorphosis. We found that during Xenopus embryogenesis, initially, CSF fills the primitive ventricular space and remains static, followed by the initiation of the cilia driven CSF circulation where ependymal cilia create a polarized CSF flow. No pulsatile flow was detected throughout these tailbud and early tadpole stages. As development progressed, despite the emergence of the choroid plexus in Xenopus, cardiac forces did not contribute to the CSF circulation, and ciliary flow remained the driver of the intercompartmental bidirectional flow as well as the near-wall flow. We finally showed that cilia driven flow is crucial for proper rostral development and regulated the spatial neural cell organization. Conclusions Our data support a paradigm in which Xenopus embryonic ventriculogenesis and rostral brain development are critically dependent on ependymal cilia-driven CSF flow currents that are generated independently of cardiac pulsatile forces. Our work suggests that the Xenopus ventricular system forms a complex cilia-driven CSF flow network which regulates neural cell organization. This work will redirect efforts to understand the molecular regulators of embryonic CSF flow by focusing attention on motile cilia rather than other forces relevant only to the adult.

Sign in / Sign up

Export Citation Format

Share Document