The use of polarization-maintaining (PM) fibers for polarization-sensitive optical coherence tomography (PS-OCT) can result in numerous image artifacts which degrade the reliability of birefringence measurements. Similar artifacts can also arise in conventional OCT, due to stray reflections from optical surfaces, a problem which is increasing in tandem with the steady rise in source coherence lengths. Here, a recently presented wavelet-FFT filter[Opt. Express17(10), 8567 (2009).] is combined with surface flattening displacement fields in order to suppress ghost artifacts following either a duplicate or inverse profile to that of the sample surface. In addition, horizontal coherence stripes originating from Fresnel reflections of optical components are suppressed in order to facilitate accurate surface detection. The result is an improved visualization of the phase-retardance profile within tissue, which may improve the reliability of curve-fitting methods for localized birefringence estimation. While the results are presented with a focus towards PS-OCT, the filtering method can also be applied to the removal of stray reflection artifacts in conventional OCT images.
Download full-text PDF |
Source |
|---|---|
| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6701519 | PMC |
| http://dx.doi.org/10.1364/BOE.10.004179 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Lens tension is essential for accommodative vision but remains challenging to measure with precision. Here, we present an optical coherence elastography (OCE) technique that quantifies both the tension and elastic modulus of lens tissue and capsule. This method derives mechanical parameters from surface wave dispersion across a critical frequency range of 1-30 kHz.
View Article and Find Full Text PDFMultiparametric grading of glaucoma severity by histopathology can enable post-mortem substratification of disease state.
Acta Neuropathol Commun
January 2025
Ophthalmology, Novartis Biomedical Research, Cambridge, MA, USA.
Neurodegeneration in glaucoma patients is clinically identified through longitudinal assessment of structure-function changes, including intraocular pressure, cup-to-disc ratios from fundus images, and optical coherence tomography imaging of the retinal nerve fiber layer. Use of human post-mortem ocular tissue for basic research is rising in the glaucoma field, yet there are challenges in assessing disease stage and severity, since tissue donations with informed consent are often unaccompanied by detailed pre-mortem clinical information. Further, the interpretation of disease severity based solely on anatomical and morphological assessments by histology can be affected by differences in death-to-preservation time and tissue processing.
View Article and Find Full Text PDFCoats' disease in adulthood with preserved vision after intravitreal aflibercept injection combined with laser photocoagulation : a case report.
BMC Ophthalmol
January 2025
Vitreoretinal Surgery Department, Hugo Chavez Hospital, Turmus Ayya, State of Palestine.
Background: This case report describes a rare case of Coats disease in adult female patient with preserved vision after intravitreal Aflibercept injection and laser photocoagulation.
Case Presentation: A female patient of Asian Palestinian descent, aged 20, exhibited a progressive and painless deterioration in the vision of her left eye over a period of two weeks. She exhibited no additional ocular symptoms.
Typical development of synaptic and neuronal properties can proceed without microglia in the cortex and thalamus.
Nat Neurosci
January 2025
Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, UK.
Brain-resident macrophages, microglia, have been proposed to have an active role in synaptic refinement and maturation, influencing plasticity and circuit-level connectivity. Here we show that several neurodevelopmental processes previously attributed to microglia can proceed without them. Using a genetically modified mouse that lacks microglia (Csf1r), we find that intrinsic properties, synapse number and synaptic maturation are largely normal in the hippocampal CA1 region and somatosensory cortex at stages where microglia have been implicated.
View Article and Find Full Text PDFObjective: To investigate the long-term impact of half-fluence photodynamic therapy (PDT) on chorioretinal architecture in chronic central serous chorioretinopathy (cCSCR) through novel choroidal vascularity index (CVI) versus previously established subfoveal choroidal thickness (SFCT).
Methods: This post-hoc analysis included prospectively collected swept-source optical coherence tomography (SS-OCT) images of a total of 29 cCSCR and fellow eyes (FE), acquired before, one and 12 months after PDT. CVI, total choroidal area (TCA), luminal area (LA) and stromal area (SA) were calculated using validated binarization technique.
Want AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!