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28 Cards in this Set
- Front
- Back
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What are the congenital optic nerve anomalies with neurological defects? |
Optic disc coloboma Morning glory syndrome Optic nerve head pit Optic nerve hypoplasia Optic disc drusen |
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What are the congenital optic nerve anomalies without neurological defect? |
Tilted disc Myelinated verve fibres Bergmaster’s papillae •Glial tissue |
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What is an optic disc coloboma? |
Failure of fetal cleft to close Maybe unilateral or bilateral Sporadic Autosomal dominant Part of a systemic disorder |
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What are the signs of an optic disc coloboma? |
Reduced visual acuity, amblyopia and refractive error Enlarged disc Excavation of inferior optic disc Inferior neural rim this or absent Wedge of superior neural tissue Superior visual field defect Associated with - microphthalmos - coloboma of iris, ciliary body, chorioretina May be mistaken for glaucoma |
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What is the management for an optic disc coloboma? |
Congenital abnormality - history or “problem with eye” - monitor visual field defect - in children do not conduct occlusion therapy Ensure no associated glaucomatous changes - normal IOP - reduced visual acuity - non- progressive visual field defect - enlarged optic nerve head Inform G.P and patient - refer routinely if diagnosis uncertain |
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What are the complications of an optic disc coloboma? |
Serous retinal macula detachment (soon referral) Progressive visual field loss associated with neural retinal thinning (routine referral) Rhetagamous retinal detachment (urgent referral) |
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Describe morning glory syndrome |
Visual acuity variable Variant of Coloboma Very rare; usually unilateral, bilateral even rarer Central core of glial tissue; persistent hyaloid artery remains Elevated annulus of pigmentary choroidal tissue Blood vessels radiate from disc centre Disc lies posterior to globe |
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What are the complications of morning glory syndrome? |
30% develop serous retinal detachments High incidence of strabismus |
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What is the management for morning glory syndrome? |
Have probably already been investigated and diagnosed; no referral required If not previously investigated; refer |
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What is an optic disc pit? |
V/A usually normal- unless papillomacular nerve fibres affected or complications present Usually unilateral (10-15% bilateral) Disc bigger than normal Greyish oval or round pit temporally Presents with V/A loss ~ 30 years- central serous maculopathy |
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What are the signs of an optic pit? |
Associated with arcuate scotomas - Usually superiorly - Absence of retinal ganglion Seen as round or oval excavations within the optic nerve head 1/3 DD in size - Up to 25D deep - Pigmentation variable Located temporally 80% or centrally 20% Unilateral possibly multi focal Atypical colobomas of the optic disc Associated with - high incidence of serous retinal detachment of the macula - inferior colobomas |
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What is the management of an optic pit? |
If previously investigated do not refer - educate patient - regular amsler testing If not previously investigated - refer routinely - educate patient Refer soon if presenting with recently reduced visual acuity |
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What is the ophthalmological treatment for an optic pit? |
Observation for spontaneous resolution Laser may be considered if vision is deteriorating; success rate is 25-35% Vitrectomy with air- fluid exchange and postoperative prone positioning |
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Describe an optic nerve hypoplasia |
Commonest optic nerve anomaly Hypoplasia= underdevelopment of tissue or organ Unilateral or bilateral Isolated disorder or associated with malformed eye or anomalies of the mid- line structure of the the brain Small discs fewer axons - normal amount of supporting tissue |
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What are the signs of an optic nerve hypoplasia? |
May present with - poor visual acuity - strabismus - visual field defect - other systemic neurological defects - congenital nystagmus • if condition severe Small grey disc- often goes undetected Double ring sign- white ring of visible sclera surrounding a pigmented band consist of pigment epithelium Vessels are tortuous May be segmental |
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What is the management for an optic disc hypoplasia? |
Association with astigmatism Correct refractive errors to avoid amblyopia Refer if not already been investigated- May have systemic associations |
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What is optic disc drusen? |
Axonal metabolic products Buried in optic nerve head Affects 2% of the population 75% bilateral Usually asymptomatic; transient blurring Can be sporadic or AD inheritance Primarily affects female Caucasians |
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What are the signs of optic disc drusen? |
Retinal nerve fibre thinning Visual field defects; drusen compress RNFL, variable, progressive, rare for substantial impact on visual function , no treatment available Other family members may have drusen or anomalous vessels on disc and no cup Drusen absent in first 10 years of life- drusen appears in second decade of life Irregular disc margin Waxy pearl like irregularities Small discs Absence of optic disc Anomalous vessels Spontaneous venous pulsation present in 80% cases |
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What is spontaneous venous pulsation? |
Presents in 80-90% of the normal population Vein on surface of disc is seen to collapse and then dilate in rhythm with cardiac cycle; may be subtle Disappears if intracranial pressure is elevated |
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What are the optic disc drusen associations? |
Juxtapupillary neovascularisation Arcuate and nasal step visual field defects |
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What is the management of optic disc drusen? |
Refer urgently if diagnosis uncertain - ultrasonography: detects calcific deposits as shadows - OCT: shows retinal nerve fibre thinning - Fluorescein angiography: autofluorescence prior to injection |
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Describe tilted disc |
Common Bilateral Oblique entry of optic nerve into globe Associated with myopic astigmatism Secondary glaucomatous changes easily overlooked Inferior temporal margin thin |
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What are the signs of tilted disc? |
Small oval or D shaped disc Indistinct disc margins Inferior crescent of hyperpigmentation Situs inverses Hypoplasia of RPE in inferior nasal retina |
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What is the management for tilted disc? |
Non- progressive condition No treatment possible Referral not required - inform patient and G.P - monitor visual fields May be associated with choroidal neovascularisation and sensory macula detachment |
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What are the associations with Hyperopic eyes? |
Anomalies associated with axial length: small Hyperopic eyes have crowded full discs - can also look like papilloedema; absence of: dilated capillaries, haemorrhages |
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What are the associations with myopic eyes? |
Large myopic eyes Peripapillary atrophy Temporal crescents Increased visualisation of choroidal vessels |
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What are the signs of myelinated nerve fibres? |
Asymptomatic usually: grossly affected eyes may have poor vision. Myelination of nerve fibres continues on to fundus: normally stops at lamina cribrosa Produces corresponding visual field defect. Recognisable by feathery margins of leading edge. No referral required. |
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Describe glial tissue |
Hyaloid artery remains of vitreous condensations Remnants may be seen on posterior lens surface Bermaster’s Papillae |
