In Vivo 3D Imaging of Retinal Neovascularization Using Multimodal Photoacoustic Microscopy and Optical Coherence Tomography Imaging

The pathological process of neovascularization of the retina plays a critical role in causing vision loss in several diseases, including diabetes, retinal vein occlusion, and sickle cell disease. Retinal neovascularization can lead to vitreous hemorrhage and retinal detachment, yet the pathological process of neovascularization is a complex phenomenon under active investigation. Understanding and monitoring retinal neovascularization is critically important in clinical ophthalmology. This study describes a novel multimodal ocular imaging system which combines photoacoustic microscopy (PAM) and a spectral domain optical coherence tomography (SD-OCT) to improve the visualization of retinal neovascularization (RNV), their depth, and the surrounding anatomy in living rabbits. RNV was induced in New Zealand rabbits by intravitreal injection of vascular endothelial growth factor (VEGF). The retinal vasculature before and after injection at various times was monitored and evaluated using multimodal imaging including color fundus photography, fluorescein angiography (FA), OCT, and PAM. In vivo experiments demonstrate that PAM imaging distinctly characterized the location as well as the morphology of individual RNV with high contrast at a safe laser energy of 80 nJ. SD-OCT was used to identify a cross-sectional structure of RNV. In addition, dynamic changes in the retinal morphology and retinal neovascularization were observed at day 4, 5, 6, 7, 9, 11, 14, 28, and day 35 after VEGF injection. PAM demonstrated high-resolution optical absorption of hemoglobin and vascular imaging of the retina and choroid with increased depth of penetration. With the current multimodal imaging system, RNV can be easily visualized in both 2D and 3D angiography. This multimodal ocular imaging system provides improved characterization of the microvasculature in a safe manner in larger rabbit eyes.

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Integrating photoacoustic microscopy, optical coherence tomography, OCT angiography, and fluorescence microscopy for multimodal imaging

Experimental Biology and Medicine ◽

10.1177/1535370219897584 ◽

2020 ◽

Vol 245 (4) ◽

pp. 342-347 ◽

Cited By ~ 2

Author(s):

Arash Dadkhah ◽

Shuliang Jiao

Keyword(s):

Optical Coherence Tomography ◽

Fluorescence Microscopy ◽

Multimodal Imaging ◽

Imaging System ◽

Optical Resolution ◽

Biological Tissues ◽

Large Field ◽

Optical Coherence ◽

Photoacoustic Microscopy

We have developed a multimodal imaging system, which integrated optical resolution photoacoustic microscopy, optical coherence tomography, optical coherence tomography angiography, and confocal fluorescence microscopy in one platform. The system is able to image complementary features of a biological sample by combining different contrast mechanisms. We achieved fast imaging and large field of view by combining optical scanning with mechanical scanning, similar to our previous publication. We have demonstrated the capability of the multimodal imaging system by imaging a mouse ear in vivo. Impact statement Photoacoustic microscopy-based multimodal imaging technology can provide high-resolution complementary information for biological tissues in vivo. It will potentially bring significant impact on the research and diagnosis of diseases by providing combined structural and functional information.

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Design and Implementation Guidelines for a Modular Spectral-Domain Optical Coherence Tomography Scanner

International Journal of Optics ◽

10.1155/2018/3726207 ◽

2018 ◽

Vol 2018 ◽

pp. 1-22 ◽

Cited By ~ 4

Author(s):

Farid Atry ◽

Israel Jacob De La Rosa ◽

Kevin R. Rarick ◽

Ramin Pashaie

Keyword(s):

Optical Coherence Tomography ◽

Imaging System ◽

Optical Design ◽

Spectral Domain ◽

Design Parameters ◽

Optical Coherence ◽

Custom Made ◽

Essential Knowledge ◽

Sd Oct

In the past decades, spectral-domain optical coherence tomography (SD-OCT) has transformed into a widely popular imaging technology which is used in many research and clinical applications. Despite such fast growth in the field, the technology has not been readily accessible to many research laboratories either due to the cost or inflexibility of the commercially available systems or due to the lack of essential knowledge in the field of optics to develop custom-made scanners that suit specific applications. This paper aims to provide a detailed discussion on the design and development process of a typical SD-OCT scanner. The effects of multiple design parameters, for the main optical and optomechanical components, on the overall performance of the imaging system are analyzed and discussions are provided to serve as a guideline for the development of a custom SD-OCT system. While this article can be generalized for different applications, we will demonstrate the design of a SD-OCT system and representative results for in vivo brain imaging. We explain procedures to measure the axial and transversal resolutions and field of view of the system and to understand the discrepancies between the experimental and theoretical values. The specific aim of this piece is to facilitate the process of constructing custom-made SD-OCT scanners for research groups with minimum understanding of concepts in optical design and medical imaging.

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In vivo evaluation of retinal neovascularization using chain-like cluster gold nanoparticle-enhanced multimodal photoacoustic microscopy and optical coherence tomography molecular imaging

Photons Plus Ultrasound: Imaging and Sensing 2021 ◽

10.1117/12.2577660 ◽

2021 ◽

Author(s):

Van Phuc Nguyen ◽

Yanxiu Li ◽

Wei Qian ◽

Bing Liu ◽

Jessica Henry ◽

...

Keyword(s):

Optical Coherence Tomography ◽

Molecular Imaging ◽

Gold Nanoparticle ◽

Retinal Neovascularization ◽

Optical Coherence ◽

Photoacoustic Microscopy ◽

In Vivo Evaluation

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3D Curvelet-Based Segmentation and Quantification of Drusen in Optical Coherence Tomography Images

Journal of Electrical and Computer Engineering ◽

10.1155/2017/4362603 ◽

2017 ◽

Vol 2017 ◽

pp. 1-12 ◽

Cited By ~ 3

Author(s):

M. Esmaeili ◽

A. M. Dehnavi ◽

H. Rabbani

Keyword(s):

Optical Coherence Tomography ◽

Imaging System ◽

Imaging Modality ◽

Age Related Macular Degeneration ◽

Spectral Domain ◽

Optical Coherence ◽

Treatment Protocols ◽

Age Related ◽

Sd Oct

Spectral-Domain Optical Coherence Tomography (SD-OCT) is a widely used interferometric diagnostic technique in ophthalmology that provides novel in vivo information of depth-resolved inner and outer retinal structures. This imaging modality can assist clinicians in monitoring the progression of Age-related Macular Degeneration (AMD) by providing high-resolution visualization of drusen. Quantitative tools for assessing drusen volume that are indicative of AMD progression may lead to appropriate metrics for selecting treatment protocols. To address this need, a fully automated algorithm was developed to segment drusen area and volume from SD-OCT images. The proposed algorithm consists of three parts: (1) preprocessing, which includes creating binary mask and removing possible highly reflective posterior hyaloid that is used in accurate detection of inner segment/outer segment (IS/OS) junction layer and Bruch’s membrane (BM) retinal layers; (2) coarse segmentation, in which 3D curvelet transform and graph theory are employed to get the possible candidate drusenoid regions; (3) fine segmentation, in which morphological operators are used to remove falsely extracted elongated structures and get the refined segmentation results. The proposed method was evaluated in 20 publically available volumetric scans acquired by using Bioptigen spectral-domain ophthalmic imaging system. The average true positive and false positive volume fractions (TPVF and FPVF) for the segmentation of drusenoid regions were found to be 89.15% ± 3.76 and 0.17% ± .18%, respectively.

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