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Journal of Visualized Experiments : JoVE Jul 2017Smartphone fundus photography is a simple technique to obtain ocular fundus pictures using a smartphone camera and a conventional handheld indirect ophthalmoscopy lens....
Smartphone fundus photography is a simple technique to obtain ocular fundus pictures using a smartphone camera and a conventional handheld indirect ophthalmoscopy lens. This technique is indispensable when picture documentation of optic nerve, retina, and retinal vessels is necessary but a fundus camera is not available. The main advantage of this technique is the widespread availability of smartphones that allows documentation of macula and optic nerve changes in many settings that was not previously possible. Following the well-defined steps detailed here, such as proper alignment of the phone camera, handheld lens, and the patient's pupil, is the key for obtaining a clear retina picture with no interfering light reflections and aberrations. In this paper, the optical principles of indirect ophthalmoscopy and fundus photography will be reviewed first. Then, the step-by-step method to record a good quality retinal image using a smartphone will be explained.
Topics: Fundus Oculi; Humans; Ophthalmoscopy; Photography; Smartphone
PubMed: 28715396
DOI: 10.3791/55958 -
Turkish Journal of Ophthalmology Feb 2024The choroid plays an important role in the pathophysiology of the eye. Multimodal imaging offers different techniques to examine the choroid. Fundus fluorescein... (Review)
Review
The choroid plays an important role in the pathophysiology of the eye. Multimodal imaging offers different techniques to examine the choroid. Fundus fluorescein angiography offers limited visualization of the deep layers of the fundus due to the barrier property of the retinal pigment epithelium. Therefore, indocyanine green angiography (ICGA) is widely used in the angiographic examination of the choroidal structure. ICGA is an important component of multimodal imaging in the diagnosis and treatment of many degenerative, tumoral, and inflammatory diseases of the choroid and retina. This review presents the general characteristics of ICGA and a practical approach to its clinical use.
Topics: Humans; Indocyanine Green; Retina; Fluorescein Angiography; Fundus Oculi; Choroid
PubMed: 38385319
DOI: 10.4274/tjo.galenos.2023.89735 -
Current Opinion in Neurology Feb 2019The funduscopic examination can be a technically difficult, and often omitted, portion of the neurologic examination, despite its great potential to influence patient... (Review)
Review
PURPOSE OF REVIEW
The funduscopic examination can be a technically difficult, and often omitted, portion of the neurologic examination, despite its great potential to influence patient care.
RECENT FINDINGS
Medical practitioners are often first taught to examine the ocular fundus using a direct ophthalmoscope, however, this skill requires frequent practice. Nonmydriatic tabletop and portable fundus photography and even smartphone-based photography offer alternative and practical means for approaching examination of the ocular fundus. These alternative tools have been shown to be practical in a variety of settings including ambulatory clinics and emergency departments. Decreased retinal microvascular density detected with fundus photography has been linked to accelerated rates of cognitive decline. Research has also found optic disc pallor and retinopathy detected via fundus photography to be more prevalent in patients with recent stroke or transient ischemic attack.
SUMMARY
Alternative methods of funduscopic examination based on fundus photography have the potential to improve the ease of use, portability, and availability of funduscopy. Recognition of changes in retinal microvasculature has the potential to noninvasively identify patients at the highest risk for cognitive impairment and cerebrovascular disease. However, further research is needed to determine the specific utility of measurements of retinal microvascular changes in clinical care. Innovative funduscopy techniques offer neurologists new approaches to this essential facet of the neurological examination.
Topics: Eye Diseases; Fundus Oculi; Humans; Neurologic Examination; Ophthalmoscopy; Photography
PubMed: 30516640
DOI: 10.1097/WCO.0000000000000637 -
The British Journal of Ophthalmology Jan 1981Ten patients (13 eyes) suffered from varying degrees of eclipse retinopathy during a solar eclipse on 16 February 1980. There was no correlation between severity of the...
Ten patients (13 eyes) suffered from varying degrees of eclipse retinopathy during a solar eclipse on 16 February 1980. There was no correlation between severity of the fundus lesions and the visual acuity. In 8 of the 10 eyes available for follow-up 6/6 or better visual acuity was seen. Early fluorescein studies revealed microleaks in 3 eyes (2 patients) and masking of choroidal fluorescence in 1 eye; however, 1 to 3 weeks later these eyes showed only faint window defects. It is postulated that in mild to moderate lesions there is a transient retinal capillary spasm, producing oedema in anterior retinal layers. Fluorescein angiography in such patients reveals no abnormality or only masking of choroidal fluorescence. However, severe cases develop micropunctures in the tight junctions of the pigment epithelium, leading to microleaks, which are sealed within a short period.
Topics: Adolescent; Adult; Child; Fluorescein Angiography; Follow-Up Studies; Fundus Oculi; Humans; Male; Retinal Diseases; Retinal Vessels; Sunlight
PubMed: 7448156
DOI: 10.1136/bjo.65.1.42 -
Indian Journal of Ophthalmology Apr 2021The peripheral retina is affected in a variety of retinal disorders. Traditional fundus cameras capture only a part of the fundus even when montaging techniques are... (Review)
Review
The peripheral retina is affected in a variety of retinal disorders. Traditional fundus cameras capture only a part of the fundus even when montaging techniques are used. Ultra-wide field imaging enables us to delve into the retinal periphery in greater detail. It not only facilitates assessing color images of the fundus, but also fluorescein angiography, indocyanine green angiography, fundus autofluorescence, and red and green free images. In this review, a literature search using the keywords "ultra-widefield imaging", "widefield imaging", and "peripheral retinal imaging" in English and non-English languages was done and the relevant articles were included. Ultra-wide field imaging has made new observations in the normal population as well as in eyes with retinal disorders including vascular diseases, degenerative diseases, uveitis, age-related macular degeneration, retinal and choroidal tumors and hereditary retinal dystrophies. This review aims to describe the utility of ultra-wide field imaging in various retinal disorders.
Topics: Fluorescein Angiography; Fundus Oculi; Humans; Optical Imaging; Retina; Retinal Diseases
PubMed: 33727441
DOI: 10.4103/ijo.IJO_1403_20 -
Survey of Ophthalmology 2023Glaucoma is a leading cause of irreversible vision impairment globally, and cases are continuously rising worldwide. Early detection is crucial, allowing timely... (Review)
Review
Glaucoma is a leading cause of irreversible vision impairment globally, and cases are continuously rising worldwide. Early detection is crucial, allowing timely intervention that can prevent further visual field loss. To detect glaucoma an examination of the optic nerve head via fundus imaging can be performed, at the center of which is the assessment of the optic cup and disc boundaries. Fundus imaging is noninvasive and low-cost; however, image examination relies on subjective, time-consuming, and costly expert assessments. A timely question to ask is: "Can artificial intelligence mimic glaucoma assessments made by experts?" Specifically, can artificial intelligence automatically find the boundaries of the optic cup and disc (providing a so-called segmented fundus image) and then use the segmented image to identify glaucoma with high accuracy? We conducted a comprehensive review on artificial intelligence-enabled glaucoma detection frameworks that produce and use segmented fundus images and summarized the advantages and disadvantages of such frameworks. We identified 36 relevant papers from 2011 to 2021 and 2 main approaches: 1) logical rule-based frameworks, based on a set of rules; and 2) machine learning/statistical modeling-based frameworks. We critically evaluated the state-of-art of the 2 approaches, identified gaps in the literature and pointed at areas for future research.
Topics: Humans; Artificial Intelligence; Fundus Oculi; Glaucoma; Optic Disk; Machine Learning
PubMed: 35985360
DOI: 10.1016/j.survophthal.2022.08.005 -
Translational Vision Science &... Aug 2021This study aimed to quantitative assess the fundus tessellated density (FTD) and associated factors on the basis of fundus photographs using artificial intelligence.
PURPOSE
This study aimed to quantitative assess the fundus tessellated density (FTD) and associated factors on the basis of fundus photographs using artificial intelligence.
METHODS
A detailed examination of 3468 individuals was performed. The proposed method for FTD measurements consists of image preprocessing, sample labeling, deep learning segmentation model, and FTD calculation. Fundus tessellation was extracted as region of interest and then the FTD could be obtained by calculating the average exposed choroid area of per unit area of fundus. Besides, univariate and multivariate linear regression analysis have been conducted for the statistical analysis.
RESULTS
The mean FTD was 0.14 ± 0.08 (median, 0.13; range, 0-0.39). In multivariate analysis, FTD was significantly (P < 0.001) associated with thinner subfoveal choroidal thickness, longer axial length, larger parapapillary atrophy, older age, male sex and lower body mass index. Correlation analysis suggested that the FTD increased by 33.1% (r = 0.33, P < .001) for each decade of life. Besides, correlation analysis indicated the negative correlation between FTD and spherical equivalent (SE) in the myopia participants (r = -0.25, P < 0.001), and no correlations between FTD and SE in the hypermetropia and emmetropic participants.
CONCLUSIONS
It is feasible and efficient to extract FTD information from fundus images by artificial intelligence-based imaging processing. FTD can be widely used in population screening as a new quantitative biomarker for the thickness of the subfoveal choroid. The association between FTD with pathological myopia and lower visual acuity warrants further investigation.
TRANSLATIONAL RELEVANCE
Artificial intelligence can extract valuable clinical biomarkers from fundus images and assist in population screening.
Topics: Aged; Artificial Intelligence; Cross-Sectional Studies; Fundus Oculi; Humans; Male; Myopia, Degenerative; Tomography, Optical Coherence
PubMed: 34406340
DOI: 10.1167/tvst.10.9.23 -
Indian Journal of Ophthalmology Jul 2015The methods of fundus examination include direct and indirect ophthalmoscopy and imaging with a fundus camera are an essential part of ophthalmic practice. The usage of... (Review)
Review
The methods of fundus examination include direct and indirect ophthalmoscopy and imaging with a fundus camera are an essential part of ophthalmic practice. The usage of unconventional equipment such as a hand-held video camera, smartphone, and a nasal endoscope allows one to image the fundus with advantages and some disadvantages. The advantages of these instruments are the cost-effectiveness, ultra portability and ability to obtain images in a remote setting and share the same electronically. These instruments, however, are unlikely to replace the fundus camera but then would always be an additional arsenal in an ophthalmologist's armamentarium.
Topics: Fluorescein Angiography; Fundus Oculi; Humans; Ophthalmoscopy; Retinal Diseases; Smartphone
PubMed: 26458475
DOI: 10.4103/0301-4738.167123 -
Indian Journal of Ophthalmology Oct 2022Retinal drawing with a color-coding system brings uniformity in representation of fundus findings so that clinician can decipher various lesions on a two-dimensional...
Retinal drawing with a color-coding system brings uniformity in representation of fundus findings so that clinician can decipher various lesions on a two-dimensional drawing. Existing color coding addresses most of the common retinal pathologies including preretinal, intraretinal, and subretinal lesions. However, with the advent of various imaging modalities there is deeper understanding of microanatomy of retina and associated pathologies. With this, there appears further need of newer set of color coding to include the minute details of fundus findings clinically. Through this article, we discuss few common pathologies at different levels of retina layers with color-coding dilemma which calls for a better preciseness in its clinical representations.
Topics: Color; Fluorescein Angiography; Fundus Oculi; Humans; Retina
PubMed: 36190076
DOI: 10.4103/ijo.IJO_1004_22 -
Asia-Pacific Journal of Ophthalmology... 2020Intraocular tumors are primarily diagnosed clinically. However, ancillary tests such as fluorescein angiogram provides excellent visualization of retinal tumors while... (Review)
Review
Intraocular tumors are primarily diagnosed clinically. However, ancillary tests such as fluorescein angiogram provides excellent visualization of retinal tumors while indocyanine green angiography reveals intrinsic vascular patterns of choroidal tumors. In this review, we contrast angiographic patterns of a variety of retinal, choroidal, and iris tumors.
Topics: Choroid; Eye Neoplasms; Fluorescein Angiography; Fundus Oculi; Humans; Retina
PubMed: 32960821
DOI: 10.1097/APO.0000000000000323