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Romanian Journal of Ophthalmology 2021Idiopathic intracranial hypertension (IIH) is a neuro-ophthalmological syndrome of unknown cause that can be vision-threatening, so an early diagnosis is crucial. We...
Idiopathic intracranial hypertension (IIH) is a neuro-ophthalmological syndrome of unknown cause that can be vision-threatening, so an early diagnosis is crucial. We reported a case of a 68-year-old asymptomatic male referred with a cataract in his right eye (OD). Best-corrected visual acuity (BCVA) was 70 letters (20/ 40) in the OD and 85 letters (20/ 20) in the left eye (OS). Ophthalmological examination revealed a significant nuclear cataract in the OD that explained the visual acuity. Fundus imaging showed a faint nasal margin elevation of the optic disc of both eyes (OU). Optical coherence tomography (OCT) revealed a sectorial retinal nerve fiber layer (RNFL) atrophy in the inferior quadrant in the OS. Nevertheless, visual field (VF) did not demonstrate defects. Neuroimaging was normal and examination of CSF revealed an opening pressure of 500 mmH2O. A diagnosis of IIH was confirmed and acetazolamide 250 mg twice daily was recommended. After 12 months of follow-up, RNFL thickness remained stable and VF did not confirm defects. A routine eye examination was the onset of IIH in our case. Thus, the ophthalmologist played a crucial role in the early diagnosis of this syndrome. Papilledema is usually a key criterion for IIH, so after its detection, exclusion diagnosis and treatment should be initiated in order to avoid permanent visual loss.
Topics: Aged; Humans; Male; Optic Disk; Papilledema; Pseudotumor Cerebri; Retinal Ganglion Cells; Tomography, Optical Coherence
PubMed: 34179586
DOI: 10.22336/rjo.2021.37 -
Contact Lens & Anterior Eye : the... Dec 2020While scleral lenses have been fitted using diagnostic lenses or impression moulding techniques for over a century, recent advances in anterior segment imaging such as... (Review)
Review
While scleral lenses have been fitted using diagnostic lenses or impression moulding techniques for over a century, recent advances in anterior segment imaging such as optical coherence tomography and corneo-scleral profilometry have significantly improved the current understanding of the anatomy of the anterior eye including the morphometry of the conjunctiva, sclera, and corneo-scleral junction, as well as the ocular surface shape and elevation. These technological advances in ocular imaging along with continual improvements and innovations in scleral lens design and manufacturing have led to a global increase in scleral lens prescribing. This review provides a comprehensive overview of the conjunctiva and sclera in the context of modern scleral lens practice, including anatomical variations in healthy and diseased eyes, the physiological impact of scleral lens wear, potential fitting challenges, and current approaches to lens modifications in order to minimise lens-induced complications and adverse ocular effects. Specific topics requiring further research are also discussed.
Topics: Conjunctiva; Contact Lenses; Humans; Prosthesis Fitting; Sclera; Tomography, Optical Coherence
PubMed: 32624363
DOI: 10.1016/j.clae.2020.06.005 -
Journal of Neuro-ophthalmology : the... Mar 2022Although nonarteritic anterior ischemic optic neuropathy (NAION) is considered a disorder that primarily affects the optic nerve head, optical coherence tomography (OCT)...
BACKGROUND
Although nonarteritic anterior ischemic optic neuropathy (NAION) is considered a disorder that primarily affects the optic nerve head, optical coherence tomography (OCT) shows peripapillary and foveal subretinal fluid associated with optic disc swelling from NAION. We sought to further evaluate retinal and vitreous changes in patients with NAION.
METHODS
Patients diagnosed with NAION at the New England Eye Center between 2013 and 2017 were evaluated using OCT. The presence and distribution of subretinal fluid was analyzed. Evidence of other vitreoretinal changes, including vitreopapillary traction (VPT) and the presence of hyperreflective dots (HRD), were also determined.
RESULTS
Twenty-five eyes from 20 patients who presented within 4 weeks of symptom onset were assessed. Peripapillary subretinal fluid was seen in 16 eyes (64%). Of those eyes, the subretinal fluid extended into the macula in 4 eyes (16%). Visual acuity improved in 2 of 4 eyes after subfoveal fluid resolution. Intraretinal cysts located in the peripapillary region were seen in 8 eyes (32%), HRD were noted in 11 (44.0%). There was no evidence of VPT.
CONCLUSIONS
A substantial number of patients with NAION have subretinal fluid on OCT, consistent with prior reports. Resolution of subfoveal fluid may result in some recovery of visual acuity. Other retinal changes, such as intraretinal cysts and HRD, are present but have unclear implications. We did not find evidence of a primary role of VPT in the pathophysiology of NAION.
Topics: Cysts; Humans; Nerve Fibers; Optic Disk; Optic Neuropathy, Ischemic; Retinal Ganglion Cells; Tomography, Optical Coherence
PubMed: 34001734
DOI: 10.1097/WNO.0000000000001264 -
Asia-Pacific Journal of Ophthalmology...Structural and functional alterations in the microcirculation by systemic hypertension can cause significant organ damage at the eye, heart, brain, and kidneys. As the...
Structural and functional alterations in the microcirculation by systemic hypertension can cause significant organ damage at the eye, heart, brain, and kidneys. As the retina is the only tissue in the body that allows direct imaging of small vessels, the relationship of hypertensive retinopathy signs with development of disease states in other organs have been extensively studied; large-scale epidemiological studies using fundus photography and advanced semi-automated analysis software have reported the association of retinopathy signs with hypertensive end-organ damage includes the following: stroke, dementia, and coronary heart disease. Although yielding much useful information, the vessels assessed from fundus photographs remain limited to the larger retinal arterioles and venules, and abnormalities observed may not be that of the earliest changes. Newer imaging modalities such as optical coherence tomography angiography and adaptive optics technology, which allow a greater precision in the structural quantification of retinal vessels, including capillaries, may facilitate the assessment and management of these patients. The advent of deep learning technology has also augmented the utility of fundus photographs to help create diagnostic and risk stratification systems. Particularly, deep learning systems have been shown in several large studies to be able to predict multiple cardiovascular risk factors, major adverse cardiovascular events within 5 years, and presence of coronary artery calcium, from fundus photographs alone. In the future, combining deep learning systems with the imaging precision offered by optical coherence tomography angiography and adaptive optics could pave way for systems that are able to predict adverse clinical outcomes even more accurately.
Topics: Fluorescein Angiography; Fundus Oculi; Humans; Hypertension; Retina; Retinal Vessels; Tomography, Optical Coherence
PubMed: 35533334
DOI: 10.1097/APO.0000000000000509 -
Survey of Ophthalmology 2019Optic disk pit, one of the optic disk cavitary anomalies, is generally congenital and unilateral and occurs equally in males and females. Optic disk pit maculopathy is... (Review)
Review
Optic disk pit, one of the optic disk cavitary anomalies, is generally congenital and unilateral and occurs equally in males and females. Optic disk pit maculopathy is characterized by intraretinal and subretinal fluid at the macula, causing visual deterioration. The origin of the macular fluid and the mechanism of transition to the subretinal space in optic disk pit maculopathy pathophysiology are not yet fully understood. With the evolution of imaging modalities, especially optic coherence tomography, our knowledge of this disorder continues to increase. Although many different treatments have been tried, there is no consensus on the most effective.
Topics: Eye Diseases, Hereditary; Humans; Macula Lutea; Macular Degeneration; Optic Disk; Tomography, Optical Coherence; Visual Acuity
PubMed: 30797884
DOI: 10.1016/j.survophthal.2019.02.006 -
Current Opinion in Ophthalmology May 2018Optical coherence tomography angiography (OCTA) is a novel, noninvasive imaging modality that allows assessment of the retinal and choroidal vasculature. The scope of... (Review)
Review
PURPOSE OF REVIEW
Optical coherence tomography angiography (OCTA) is a novel, noninvasive imaging modality that allows assessment of the retinal and choroidal vasculature. The scope of this review is to summarize recent studies using OCTA in glaucoma and highlight potential applications of this new technology in the field of glaucoma.
RECENT FINDINGS
OCTA studies have shown that retinal vascular changes may not develop solely as a result of advanced glaucoma damage. OCTA-derived measurements have provided evidence for lower retinal vascular densities at the optic nerve head, peripapillary and macula in preperimetric-glaucoma and early-glaucoma, as well as, in more advanced glaucoma, in comparison to with normal eyes.
SUMMARY
OCTA is a novel imaging modality that has already started to expand our knowledge base regarding the role of ocular blood flow in glaucoma. Future studies will better elucidate the role of OCTA-derived measurements in clinical practice, research, and clinical trials in glaucoma.
Topics: Angiography; Choroid; Computed Tomography Angiography; Glaucoma; Humans; Macula Lutea; Optic Disk; Retinal Vessels; Tomography, Optical Coherence
PubMed: 29553952
DOI: 10.1097/ICU.0000000000000475 -
Journal Francais D'ophtalmologie Oct 2022Located within the scleral canal, the lamina cribrosa is a sieve-like structure separating the intraocular and retrobulbar portions of the optic nerve. Identified as the... (Review)
Review
Located within the scleral canal, the lamina cribrosa is a sieve-like structure separating the intraocular and retrobulbar portions of the optic nerve. Identified as the main site of axonal damage in glaucomatous optic neuropathy, the study of the lamina cribrosa has been of great interest for many years. Numerous studies have explored the histological and morphological characteristics of the laminar region in healthy subjects as well as glaucoma patients. More recently, the development of adaptive optics systems and new generations of OCT has allowed great progress in the understanding of the pathogenesis of glaucoma and has opened new perspectives for the improvement of diagnostic procedures.
Topics: Glaucoma; Humans; Intraocular Pressure; Optic Disk; Optic Nerve; Optic Nerve Diseases; Tomography, Optical Coherence
PubMed: 35717219
DOI: 10.1016/j.jfo.2022.03.003 -
Eye (London, England) Nov 2019We investigated the effects of topical phenylephrine 2.5% instillation on choroidal thickness (CT), peripapillary choroidal thickness (pCT) and retinal nerve fibre layer...
OBJECTIVES
We investigated the effects of topical phenylephrine 2.5% instillation on choroidal thickness (CT), peripapillary choroidal thickness (pCT) and retinal nerve fibre layer (RNFL).
METHODS
Healthy control patients underwent enhanced depth imaging (EDI) by spectral-domain optical coherence tomography (OCT) before and 30 min after phenylephrine instillation, using eye-tracking and follow-up software. Changes in 14 different locations of CT, 2 locations of pCT and RNFL were assessed.
RESULTS
The study included 119 eyes of 62 patients (19 males and 43 females), with a mean age of 59.8 ± 15.3 years (range: 26-88 years). Within 30 min after instillation, the mean subfoveal CT both in vertical and horizontal scan were significantly thinned (p = 0.005 and p = 0.018, respectively). In total, 1500, 1000 and 500 µm temporal CT measurements showed also a significant thinning (p = 0.021, p = 0.037 and p = 0.020, respectively), as well as 500 µm both superior (p = 0.045) and inferior (p = 0.009). 1500, 1000 and 500 µm nasal CT, and 1500 and 1000 µm CT superior and inferior measurements showed no significant thinning after phenylephrine instillation. pCT was significantly thinned after phenylephrine in both superior (p = 0.016) and inferior (p = 0.050) measurements. RNFL analysis did not significantly change after phenylephrine instillation (p = 0.209).
CONCLUSIONS
A significant thinning of CT and pCT occurred following phenylephrine instillation. Future studies analysing CT and pCT should detail if this mydriatic agent was used or not.
Topics: Administration, Ophthalmic; Adult; Aged; Aged, 80 and over; Choroid; Female; Healthy Volunteers; Humans; Macula Lutea; Male; Middle Aged; Mydriatics; Nerve Fibers; Ophthalmic Solutions; Optic Disk; Phenylephrine; Pupil; Retinal Ganglion Cells; Tomography, Optical Coherence
PubMed: 31164729
DOI: 10.1038/s41433-019-0478-z -
Physiological Reviews Jul 2024The anterior chamber of the eye (ACE) is distinct in its anatomy, optics, and immunology. This guarantees that the eye perceives visual information in the context of... (Review)
Review
The anterior chamber of the eye (ACE) is distinct in its anatomy, optics, and immunology. This guarantees that the eye perceives visual information in the context of physiology even when encountering adverse incidents like inflammation. In addition, this endows the ACE with the special nursery bed iris enriched in vasculatures and nerves. The ACE constitutes a confined space enclosing an oxygen/nutrient-rich, immune-privileged, and less stressful milieu as well as an optically transparent medium. Therefore, aside from visual perception, the ACE unexpectedly serves as an excellent transplantation site for different body parts and a unique platform for noninvasive, longitudinal, and intravital microimaging of different grafts. On the basis of these merits, the ACE technology has evolved from the prototypical through the conventional to the advanced version. Studies using this technology as a versatile biomedical research platform have led to a diverse range of basic knowledge and in-depth understanding of a variety of cells, tissues, and organs as well as artificial biomaterials, pharmaceuticals, and abiotic substances. Remarkably, the technology turns in vivo dynamic imaging of the morphological characteristics, organotypic features, developmental fates, and specific functions of intracameral grafts into reality under physiological and pathological conditions. Here we review the anatomical, optical, and immunological bases as well as technical details of the ACE technology. Moreover, we discuss major achievements obtained and potential prospective avenues for this technology.
Topics: Humans; Prospective Studies; Anterior Chamber
PubMed: 38206586
DOI: 10.1152/physrev.00024.2023 -
Optometry and Vision Science : Official... Sep 2017To maximize efficiency of the normally lengthy and costly multizone lens design and testing process, it is advantageous to evaluate the potential efficacy of a design as...
SIGNIFICANCE
To maximize efficiency of the normally lengthy and costly multizone lens design and testing process, it is advantageous to evaluate the potential efficacy of a design as thoroughly as possible prior to lens fabrication and on-eye testing. The current work describes an ex vivo approach of optical design testing.
PURPOSE
The aim of this study was to describe a system capable of examining the optical characteristics of multizone bifocal and multifocal optics by subaperture stitching using liquid crystal technologies.
METHODS
A liquid crystal spatial light modulator (SLM) was incorporated in each of two channels to generate complementary subapertures by amplitude modulation. Additional trial lenses and phase plates were placed in pupil conjugate planes of either channel to integrate the desired bifocal and multifocal optics once the two optical paths were recombined. A high-resolution Shack-Hartmann aberrometer was integrated to measure the optics of the dual-channel system. Power and wavefront error maps as well as point spread functions were measured and computed for each of three multizone multifocal designs.
RESULTS
High transmission modulation was achieved by introducing half-wavelength optical path differences to create two- and five-zone bifocal apertures. Dual-channel stitching revealed classic annular rings in the point spread functions generated from two-zone designs when the outer annular optic was defocused. However, low efficiency of the SLM prevented us from simultaneously measuring the eye + simulator aberrations, and the higher-order diffraction patterns generated by the cellular structure of the liquid crystal arrays limited the visual field to ±0.45 degrees.
CONCLUSIONS
The system successfully simulated bifocal and multifocal simultaneous lenses allowing for future evaluation of both objective and subjective evaluation of complex optical designs. However, low efficiency and diffraction phenomena of the SLM limit the utility of this technology for simulating multizone and multifocal optics.
Topics: Eyeglasses; Humans; Light; Liquid Crystals; Optics and Photonics; Pupil
PubMed: 28816865
DOI: 10.1097/OPX.0000000000001108