Classification of Human Retinal Microaneurysms Using Adaptive Optics Scanning Light Ophthalmoscope Fluorescein Angiography

Context. Direct imaging provides a steady flow of newly discovered giant planets and brown dwarf companions. These multi-object systems can provide information about the formation of low-mass companions in wide orbits and/or help us to speculate about possible migration scenarios. Accurate classification of companions is crucial for testing formation pathways. Aims. In this work we further characterise the recently discovered candidate for a planetary-mass companion CS Cha b and determine if it is still accreting. Methods. MUSE is a four-laser-adaptive-optics-assisted medium-resolution integral-field spectrograph in the optical part of the spectrum. We observed the CS Cha system to obtain the first spectrum of CS Cha b. The companion is characterised by modelling both the spectrum from 6300 Å to 9300 Å and the photometry using archival data from the visible to the near-infrared (NIR). Results. We find evidence of accretion and outflow signatures in Hα and OI emission. The atmospheric models with the highest likelihood indicate an effective temperature of 3450 ± 50 K with a log g of 3.6 ± 0.5 dex. Based on evolutionary models, we find that the majority of the object is obscured. We determine the mass of the faint companion with several methods to be between 0.07 M⊙ and 0.71 M⊙ with an accretion rate of Ṁ = 4 × 10−11±0.4 M⊙ yr−1. Conclusions. Our results show that CS Cha B is most likely a mid-M-type star that is obscured by a highly inclined disc, which has led to its previous classification using broadband NIR photometry as a planetary-mass companion. This shows that it is important and necessary to observe over a broad spectral range to constrain the nature of faint companions.

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Imaging Foveal Microvasculature: Optical Coherence Tomography Angiography Versus Adaptive Optics Scanning Light Ophthalmoscope Fluorescein Angiography

Investigative Opthalmology & Visual Science ◽

10.1167/iovs.15-18932 ◽

2016 ◽

Vol 57 (9) ◽

pp. OCT130 ◽

Cited By ~ 56

Author(s):

Shelley Mo ◽

Brian Krawitz ◽

Eleni Efstathiadis ◽

Lawrence Geyman ◽

Rishard Weitz ◽

...

Keyword(s):

Optical Coherence Tomography ◽

Fluorescein Angiography ◽

Adaptive Optics ◽

Optical Coherence Tomography Angiography ◽

Optical Coherence

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Dynamic Changes of Retinal Microaneurysms in Diabetes Imaged With In Vivo Adaptive Optics Optical Coherence Tomography

Investigative Opthalmology & Visual Science ◽

10.1167/iovs.18-24573 ◽

2018 ◽

Vol 59 (15) ◽

pp. 5932 ◽

Cited By ~ 3

Author(s):

Julia Hafner ◽

Matthias Salas ◽

Christoph Scholda ◽

Wolf-Dieter Vogl ◽

Wolfgang Drexler ◽

...

Keyword(s):

Optical Coherence Tomography ◽

Adaptive Optics ◽

Optical Coherence ◽

Dynamic Changes ◽

Retinal Microaneurysms

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Microaneurysms visualisation using five different optical coherence tomography angiography devices compared to fluorescein angiography

British Journal of Ophthalmology ◽

10.1136/bjophthalmol-2020-316817 ◽

2020 ◽

pp. bjophthalmol-2020-316817 ◽

Cited By ~ 2

Author(s):

Salvatore Parrulli ◽

Federico Corvi ◽

Mariano Cozzi ◽

Davide Monteduro ◽

Federico Zicarelli ◽

...

Keyword(s):

Optical Coherence Tomography ◽

Fluorescein Angiography ◽

Optical Coherence Tomography Angiography ◽

Imaging Modality ◽

Optical Coherence ◽

Capillary Plexus ◽

Retinal Microaneurysms ◽

Scan Pattern ◽

Superficial Capillary Plexus ◽

Higher Sensitivity

BackgroundTo compare fluorescein angiography (FA) and five different optical coherence tomography angiography (OCTA) devices and to test their reproducibility in the evaluation of retinal microaneurysms (MAs) secondary to diabetic retinopathy (DR).MethodsOn the same day, patients with DR were imaged with FA and five OCTA devices: prototype Spectralis OCTA, prototype PlexElite, RTVue XR Avanti, AngioPlex and DRI OCT Triton. For all OCTA devices, a 3×3 volume scan pattern was performed. MAs were evaluated for the superficial capillary plexus (SCP) and deep capillary plexus (DCP).ResultsTwenty eyes of 15 patients with DR were included. FA counted a significantly higher number of MAs compared to OCTA devices. Spectralis OCTA obtained a significantly higher number of MAs compared to PlexElite, RTVue XR Avanti, AngioPlex and DRI OCT Triton (p<0.0001). PlexElite and AngioPlex showed a greater number of MAs in the SCP, Spectralis OCTA, RTVue XR Avanti and DRI OCT Triton in the DCP. Higher sensitivity (43.3%) but lowest specificity (54.4%) was observed for Spectralis OCTA compared to other devices. The higher specificity (78.5%) and positive predictive value (83.3%) were observed for DRI OCT Triton.ConclusionsFA remains the best imaging modality to visualise retinal MAs. Spectralis OCTA was able to detect more MAs compared to other devices, likely due to the higher number of B-scans in the scanned area as well as due to the higher number of repeated B-scans. The high variability between OCTA devices should be taken into account for future clinical trials as in clinical practice.

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Residual misalignments of the Keck Telescope primary mirror segments: classification of modes and implications for adaptive optics

10.1117/12.319318 ◽

1998 ◽

Cited By ~ 2

Author(s):

Mitchell Troy ◽

Gary A. Chanan ◽

Edwin Sirko ◽

Emily Leffert

Keyword(s):

Adaptive Optics ◽

Primary Mirror

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RAC-CNN: multimodal deep learning based automatic detection and classification of rod and cone photoreceptors in adaptive optics scanning light ophthalmoscope images

Biomedical Optics Express ◽

10.1364/boe.10.003815 ◽

2019 ◽

Vol 10 (8) ◽

pp. 3815 ◽

Cited By ~ 8

Author(s):

David Cunefare ◽

Alison L. Huckenpahler ◽

Emily J. Patterson ◽

Alfredo Dubra ◽

Joseph Carroll ◽

...

Keyword(s):

Deep Learning ◽

Adaptive Optics ◽

Automatic Detection ◽

Cone Photoreceptors ◽

Rod And Cone Photoreceptors

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Clinical Diagnosis and Classification of Branch Retinal Vein Occlusion and Macular Edema

Güncel Retina Dergisi (Current Retina Journal) ◽

10.37783/crj-0143 ◽

2019 ◽

pp. 76-82

Keyword(s):

Optical Coherence Tomography ◽

Fluorescein Angiography ◽

Macular Edema ◽

Retinal Vein Occlusion ◽

Branch Retinal Vein Occlusion ◽

Significant Contribution ◽

Anatomical Location ◽

Vein Occlusion ◽

Diagnosis And Classification

Branch retinal vein occlusion (BRVO) is classified according to the anatomical location as a major, hemiretinal, or macular. BRVO is further classified into perfused (non-ischemic) or nonperfused (ischemic). Ischemic BRVO is defined as more than 5 disc diameters of nonperfusion on fluorescein angiography (FA). There is a significant contribution of FA and Optical Coherence Tomography in predicting treatment and determining prognosis.

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