To improve the reproducibility of photocoagulation, the ability to quantitatively monitor the thermal change of laser-irradiated retinal tissue is required. Recently, optical coherence tomography has enabled non-invasive and non-contact monitoring of the tissue structural changes during laser irradiation. To further improve the capability of this technique, a method is proposed to measure tissue displacement by simultaneously using Doppler phase shifts and correlation coefficients. The theoretical approach for this method is described, and its performance is experimentally confirmed and evaluated. Finally, lateral and axial displacements in the laser-irradiated retinal tissues of an enucleated porcine eye are observed. The proposed method is found to be useful for further understanding the direct thermal response of laser-irradiated retinal tissue.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4317133 | PMC |
http://dx.doi.org/10.1364/BOE.6.000170 | DOI Listing |
J Cell Mol Med
October 2022
Department of Ophthalmology, Wakayama Medical University, Wakayama, Japan.
We investigated the effects of lacking TNFα on the development and regression of Argon-laser-induced choroidal neovascularization (CNV) in mice. We lasered ocular fundus for induction of CNV in both wild-type (WT) and TNFα-null (KO) mice. Fluorescence angiography was performed to examine the size of CNV lesions.
View Article and Find Full Text PDFDrug Deliv
December 2022
Department of Ophthalmology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, PR China.
Retinoblastoma (RB) is a malignant intraocular neoplasm that occurs in children. Diagnosis and therapy are frequently delayed, often leading to metastasis, which necessitates effective imaging and treatment. In recent years, the use of nanoplatforms allowing both imaging and targeted treatment has attracted much attention.
View Article and Find Full Text PDFBiomed Phys Eng Express
December 2021
Laser Physics & Photonic Devices Laboratories, UniSA STEM, University of South Australia, Mawson Lakes, SA, 5095, Australia.
A realistic model of human retinal tissues to simulate thermal performance of optical laser photocoagulation therapy is presented. The key criteria to validate the treatment effectiveness is to ensure the photocoagulation temperature between 60 and 70 °C is reached in the treatment region of interest. The model presented consists of truncated volumes of the retinal pigment epithelium (RPE) and adjacent retinal tissues.
View Article and Find Full Text PDFCurr Gene Ther
August 2020
Nanoscope Technologies LLC, 1312 Brown Trail, Bedford, TX, 76022, United States.
Background: The efficient and targeted delivery of genes and other impermeable therapeutic molecules into retinal cells is of immense importance for the therapy of various visual disorders. Traditional methods for gene delivery require viral transfection, or chemical methods that suffer from one or many drawbacks, such as low efficiency, lack of spatially targeted delivery, and can generally have deleterious effects, such as unexpected inflammatory responses and immunological reactions.
Methods: We aim to develop a continuous wave near-infrared laser-based Nano-enhanced Optical Delivery (NOD) method for spatially controlled delivery of ambient-light-activatable Muti-Characteristic opsin-encoding genes into retina in-vivo and ex-vivo.
We propose a method to measure the in-plane and out-of-plane displacements of tissue using the correlation coefficients of optical coherence tomography (OCT) signals. The displacements are determined by the local correlation coefficients between digitally shifted reference OCT images and a target image. The method achieves sub-micron displacement measurement with an accuracy better than 0.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!