Showing papers on "Optic Disk Drusen published in 2014"

Assessment of optic nerve head drusen using enhanced depth imaging and swept source optical coherence tomography.

Abstract: Optic nerve head drusen (ONHD) are acellular deposits of calcium, amino and nucleic acids, and mucopolysaccharides, buried or at the surface of the optic disc (1–3). When located near the surface, drusen can be directly visualized by ophthalmoscopy. Superficial drusen typically confer an irregular lumpy appearance to the optic disc (4). It is hypothesized that some superficial drusen become visible with age as a result of drusen growth or loss of the neural tissue that obscures the drusen. In contrast, when disc drusen are located closer to the lamina cribrosa, they can be difficult to detect and may require imaging for confirmatory diagnosis (5,6). Although ONHD are normally asymptomatic, they are associated with visual field defects in 24%–87% of affected adults (4,5,7). Wilkens et al (8) found that superficial drusen were more commonly associated with visual field defects than deep drusen. The mechanism of drusen-related visual field loss is poorly understood. ONHD typically enlarge slowly throughout life and a slow progression of visual field loss is common (4,5,7). In rare cases, acute decreases in vision can occur due to vascular occlusion (9). Recent advances in ocular imaging have improved our ability to image ONHD and have provided a means to obtain objective, quantitative measurements of ONHD and neighboring structures, including the retinal nerve fiber layer (RNFL) (5,10). Better in vivo imaging has the potential to improve our understanding of the pathogenesis of drusen-related visual field damage. The purpose of this review was to describe the use of 2 new optical coherence tomography (OCT) methods, enhanced depth imaging optical coherence tomography (EDI-OCT) and swept source optical coherence tomography (SS-OCT), and to evaluate their application in the assessment of ONHD.

Optical coherence tomography in papilledema and pseudopapilledema with and without optic nerve head drusen

Abstract: Aim: To compare the spectral domain optical coherence tomography (SD-OCT) findings of the optic disc and the peripapillary retina of patients with a true papilledema and pseudopapilledema with and without optic nerve head drusen (ONHD). Study Design: Retrospective Case Control Study. Subjects and Methods: Peripapillary retinal nerve fiber layer (PPRNFL) thickness as depicted by SD-OCT of 94 eyes of 66 patients with papilledema (30 eyes), pseudopapiledema (31 eyes), and normal controls (33 eyes) was analyzed. The mean RNFL thickness, total retinal thickness (TRT) at a superior and inferior edge of the disc and the quadrant wise topography of increased RNFL were compared in all three groups. Sensitivity, specificity, and area under the receiver operating characteristic curve (AROC) were calculated for all the parameters. Results: The median RNFL thickness was 185.4 (129.5-349.3 μm), 122.3 (109-156.3 μm) and 91.62 ± 7 μm in papilledema, pseudopapilledema, and controls, respectively. Papilledema group had thicker PPRNFL in all quadrants except temporal quadrant. TRT was thicker in papilledema and pseudopapilledema compared to controls. ONHD could be directly visualized as high reflective clumps in the sub-retinal space or the RNFL in 30 eyes. Increased RNFL thickness in all four quadrants was noted 43.3% in papilledema and 9.7% in pseudopapilledema. Normal RNFL thickness in all four quadrants was noted in 0% in papilledema and 32.3% in pseudopapilledema. Nasal RNFL had the highest AROC (0.792) indicating high diagnostic ability to differentiate papilledema from pseudopapilledema. Conclusion: SD-OCT can be used as a tool to differentiate between papilledema and pseudopapilledema.

Mouse genetics and proteomic analyses demonstrate a critical role for complement in a model of DHRD/ML, an inherited macular degeneration

Abstract: Macular degenerations, inherited and age related, are important causes of vision loss. Human genetic studies have suggested perturbation of the complement system is important in the pathogenesis of age-related macular degeneration. The mechanisms underlying the involvement of the complement system are not understood, although complement and inflammation have been implicated in drusen formation. Drusen are an early clinical hallmark of inherited and age-related forms of macular degeneration. We studied one of the earliest stages of macular degeneration which precedes and leads to the formation of drusen, i.e. the formation of basal deposits. The studies were done using a mouse model of the inherited macular dystrophy Doyne Honeycomb Retinal Dystrophy/Malattia Leventinese (DHRD/ML) which is caused by a p.Arg345Trp mutation in EFEMP1. The hallmark of DHRD/ML is the formation of drusen at an early age, and gene targeted Efemp1R345W/R345W mice develop extensive basal deposits. Proteomic analyses of Bruch's membrane/choroid and Bruch's membrane in the Efemp1R345W/R345W mice indicate that the basal deposits comprise normal extracellular matrix (ECM) components present in abnormal amounts. The proteomic analyses also identified significant changes in proteins with immune-related function, including complement components, in the diseased tissue samples. Genetic ablation of the complement response via generation of Efemp1R345W/R345W:C3−/− double-mutant mice inhibited the formation of basal deposits. The results demonstrate a critical role for the complement system in basal deposit formation, and suggest that complement-mediated recognition of abnormal ECM may participate in basal deposit formation in DHRD/ML and perhaps other macular degenerations.

The cost-effectiveness of different strategies to evaluate optic disk drusen in children.

Abstract: Purpose To compare the costs of diagnostic work-up for optic disk drusen where ophthalmic ultrasound was performed prior to imaging and invasive studies with those where ophthalmic ultrasound was performed after such studies. Methods The medical records of patients Results A total of 46 children with a B-scan ultrasound–confirmed diagnosis of calcified optic disk drusen were included. Neuroimaging was performed in 23 patients, of whom 20 had the study prior to ophthalmic ultrasound. The mean cost of evaluations for patients undergoing ancillary testing prior to ophthalmic ultrasound was $1,173; for those undergoing ancillary testing after, $305. Conclusions Because optic disk drusen can mimic the appearance of papilledema, it is more cost-effective to perform ophthalmic ultrasonography prior to neuroimaging, especially when the patient is asymptomatic. If ophthalmic ultrasonography confirms the presence of drusen, it is more cost-effective to reassess the clinical picture before proceeding with further tests.

Measuring Cone Density in a Japanese Macaque (Macaca fuscata) Model of Age-Related Macular Degeneration with Commercially Available Adaptive Optics

Abstract: The aim of this study was to assess the feasibility of using a commercially available high-resolution adaptive optics (AO) camera to image the cone mosaic in Japanese macaques (Macaca fuscata) with dominantly inherited drusen. The macaques examined develop drusen closely resembling those seen in humans with age-related macular degeneration (AMD). For each animal, we acquired and processed images from the AO camera, montaged the results into a composite image, applied custom cone-counting software to detect individual cone photoreceptors, and created a cone density map of the macular region. We conclude that flood-illuminated AO provides a promising method of visualizing the cone mosaic in nonhuman primates. Future studies will quantify the longitudinal change in the cone mosaic and its relationship to the severity of drusen in these animals.

[Optic disc drusen - current diagnostic possibilities].

Abstract: Authors present the findings of two patients with optic nerve drusen, and an overview of current examination techniques in the diagnostics of optic nerve drusen including ultrasound examination, fundus photography, florescein angiography, computerized perimetry, auto-florescence fundus examination, examination of the nerve fibre layer using optical coherence tomography (OCT) or nerve fibres layer analyzer (GDx). In the first case, the patient was recommended to be supervised without any therapy. The second patient with regard to perimeter finding, loss of nerve fibre layer and increase of the intraocular pressure was prescribed local anti-glaucoma therapy.

Retinal hemorrhages as one of complications of optic disc drusen during pregnancy.

Abstract: Introduction. Drusen of the optic nerve head are relatively benign and asymptomatic. They represent retinal hyaline corpuscles resulting from impaired axoplasmic transport of the retinal ganglion cells of optic nerve in front of the lamina cribrosa. They are usually detected accidentally, during a routine ophthalmologic examination. Most patients with optic disc drusen are not aware of the deterioration of their eyesight because of the slow progression of visual field defects. Damage in visual acuity due to optic disc drusen is rare. Case Report. A 27-year-old female patient in the sixth month of pregnancy visited an ophthalmologist because of a visual impairment described as the appearance of mist and shadows over her right eye. When first examined, her visual acuity in both eyes was 20/20. The retinal hemorrhages framing the bottom half of the optic nerve were seen. Complete laboratory and clinical testing as well as specific ophthalmic examinations (photofundus, computerized visual field, optical coherence tomography, and ultrasound) were performed to exclude systemic causes and they presented no risk for the pregnancy. Echosonographic examination confirmed the presence of bilateral optic nerve head drusen. Conclusion. Hemodynamic changes during pregnancy are possible factors for the development of optical disc and retinal hemorrhages. Since treatment of optic disc drusen is limited, recognition of optic nerve drusen as a cause of hemorrhage during pregnancy prevents unnecessary diagnostic and therapeutic interventions.