drusen


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drusen

 [droo´sen]
1. abnormal growths of hyaline in Bruch's membrane, the inner layer of the choroid of the eye, usually due to aging.
2. rosettes of granules occurring in the lesions of actinomycosis.

dru·sen

(drū'sen),
Small bright structures seen in the retina and in the optic disk.
[Ger. pl. of Druse, stony nodule, geode]

drusen

/dru·sen/ (droo´zen) [Ger.]
1. hyaline excrescences in Bruch's membrane of the eye, usually due to aging.
2. rosettes of granules occurring in the lesions of actinomycosis.

drusen

[dro̅o̅′zən]
Etymology: Ger, Drüse, stony granule
small yellowish hyaline deposits that develop beneath the retinal pigment epithelium, sometimes appearing as nodules within the optic nerve head. They tend to occur most frequently in persons older than 60 years of age and are commonly associated with age-related macular degeneration.
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Retinal drusen

drusen

Ophthalmology Acellular and amorphous, yellow-white, occasionally confluent nodules composed of aggregated abnormal glycoproteins and glycolipids produced by, and adjacent to, the basal cells of the retinal pigment epithelium

dru·sen

(drū'sĕn)
Small, bright structures seen in the retina and in the optic disc.
[Ger. pl. of Druse, stony nodule, geode]

Drusen

Tiny yellow dots on the retina that can be soft or hard and that usually do not interfere with vision.
Mentioned in: Macular Degeneration

drusen

Small, circular, yellow or white dots located throughout the fundus but more so in the macular region, around the optic disc or the periphery. They consist of deposits of abnormal extracellular material (amyloid P, complement proteins (C3, C5, C5b-9 complex), factors C, apolipoproteins B and E, lipids, vitronectin, etc.) derived mainly from the retinal pigment epithelium (RPE) and neural retina and they are located between the basement membrane of the RPE and Bruch's membrane. Drusen interfere with the blood supply to the photoreceptors. Although they may be found in young people, they almost universally occur with ageing but also with retinal and choroidal degeneration (e.g. age-related maculopathy, retinitis pigmentosa, angioid streaks) and primary dystrophy (e.g. fundus flavimaculatus). There are several main types of drusen: (1) Hard (or nodular) drusen are small, round and discrete. They are deposits of granular material as well as of abnormal collagen. They are the most common type and are usually innocuous. (2) Soft (or diffuse or granular) drusen are often large with indistinct edges and with time they may enlarge, coalesce and increase in number. They are due to either a focal thickening of the inner layer of Bruch's membrane or to amorphous material located between that thickened, detached part and the rest of Bruch's membrane. They represent an early feature of age-related macular degeneration. (3) Cuticular (or basal laminar) drusen are small subretinal nodular thickening of the basement membrane of the pigment epithelium. They occur in younger patients more often than hard or soft drusen. (4) With time, the above drusen may calcify (calcific drusen) and take on a glistening appearance. Drusen rarely produce any symptoms and if there is a visual loss it is usually due to an accompanying macular haemorrhage, but if the drusen are very large thus widening the separation between the RPE and Bruch's membrane there may be a degeneration of the overlying RPE and photoreceptors (Fig. D11). Syn. colloid bodies; hyaline bodies. See age-related macular degeneration; choroidal naevus.
familial dominant drusen An autosomal dominant hereditary degeneration of the choroid characterized by light-coloured patches of colloid material in the area around the macula and often the optic disc. The majority of cases are caused by mutations in the EFEMP1 gene (egf-containing fibulin-like extracellular matrix protein 1). There is no loss of vision unless it is followed by macular degeneration. Syn. Doyne's honeycomb choroiditis; Doyne's honeycombed degeneration; Tay's choroiditis (used more commonly for the elderly).
optic disc drusen Whitish-yellow spherical excrescences that lie on, or within, or occasionally around the optic nerve head. They are composed of calcified hyaline-like material possibly resulting from deposition of mucoprotein and calcium that have extruded from degenerating axons. In childhood they are usually buried within the disc substance and thus not visible on clinical examination but cause elevation of the disc surface resembling papilloedema. With age they become progressively more superficial. Field defects are common (e.g. generalized constriction, blind spot enlargement) but visual acuity is normal, unless there is some vascular complication. They usually appear bilaterally and affect males and females equally. They are easily diagnosed with fluorescein angiography because exposed drusen are autofluorescent.
Fig. D11 Calcified drusenenlarge picture
Fig. D11 Calcified drusen

drusen

1. hyaline excrescences in Bruch's membrane, the inner layer of the choroid of the eye, usually due to aging.
2. rosettes of granules occurring in the lesions of actinomycosis. Called also sulfur granules.
References in periodicals archive ?
The study found that, the percentage of convex drusen that shrank or disappeared after 12 weeks of treatment was significantly higher in the glatiramer-treated group (27.
The intracellular lipid accumulation in RPE leads to AMD that appears in the form of Bruch's membrane deposits and drusen.
Before the optical coherence tomography (OCT) era, drusen were graded upon their width (small, intermediate or large) and appearance (soft, hard or confluent) on color fundus photography or with indirect ophthalmoscopy (10).
However, insufficient digestion due to impaired autophagy or lysosomal degradation in the RPE can lead to an accumulation of damaged organelles, toxic proteins (including lipofuscin), and extracellular drusen deposits, all of which can contribute to RPE dysfunction or RPE cell death, which have been associated with the pathogenesis of AMD [139].
Most patients with drusen are not aware of the deterioration of their sight because the slow progression of visual field defects.
If drusen build up, they can disrupt the RPE, the photoreceptors, and vision (dry macular degeneration).
In most cases various digital filters are used to find drusen [1-3], although other methods, including thresholding by Otsu method is also used [4], Markov random fields [3] or cellular neural networks [5] have also been tried.
The mice developed drusen, the deposits in the retina that are present in the majority of people affected by AMD.
Early-onset drusen in a girl with Bloom Syndrome: Probable clinical importance of an oculer manifestation.
Mechanisms addressed here include diabetes, statins, Drusen, RPE lipofuscin, genetic modifiers, X-linked retinal dystrophies and synaptic remodeling, while therapeutic strategies include the suppression of photoreceptor cell death, cell-based therapies, IPE transplantation, retinal transplantation, stem cells, encapsulated cell technology, neuroprotective factors, and carbon anhydrase inhibitors.