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26/02/2008

Optic fundus in clinical medicine

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Page 1: Optic fundus in clinical medicine

26/02/2008

Page 2: Optic fundus in clinical medicine

Only place in the body where blood vessels can be visualized directly

Mirror the status of the systemic circulation

Continuity of nerve fibers and meninges

Reflects specific changes in systemic diseases

Contribute to diagnosis

Page 3: Optic fundus in clinical medicine

Direct ophthalmoscopy

Indirect opthalmoscopySterioscopical view possible

Page 4: Optic fundus in clinical medicine

Ideally fundus should be examined in a darkened room

Patient should be asked to fix their gaze on a distant object

Examine with corresponding eyes

The ideal line of approach should bring the optic disc straight in to view

If only blood vessels on a pink background are seen they should be followed , the disk will eventually come in to view

Page 5: Optic fundus in clinical medicine

Media- hazy, clear

Disc- size, shape, colour, margin, physiological cup, neuroretinal rim

Blood vessels- caliber, tortousity, irregularities, changes in the vessel wall, aneurism, neovascularisation

Exudates

Haemorrhage

Page 6: Optic fundus in clinical medicine

Uniform red to pink

Disc-pale pink

1.5 mm in diameter

Nasal margin slightly blurred

Vessels emanate from optic cup

Consist of central cup and

peripheral neuroretinal rim

Macula temporally

Fovea 2.5mm-diameter, darker

Page 7: Optic fundus in clinical medicine

Uniform red to pink

Disc-pale pink

1.5 mm in diameter

Nasal margin slightly blurred

Vessels emanate from optic cup

Consist of central cup and

peripheral neuroretinal rim

Macula temporally

Fovea 2.5mm-diameter, darker

Page 8: Optic fundus in clinical medicine

Uniform red to pink

Disc-pale pink

1.5 mm in diameter

Nasal margin slightly blurred

Vessels emanate from optic cup

Consist of central cup and

peripheral neuroretinal rim

Macula temporally

Fovea 2.5mm-diameter, darker

Page 9: Optic fundus in clinical medicine

Uniform red to pink

Disc-pale pink

1.5 mm in diameter

Nasal margin slightly blurred

Vessels emanate from optic cup

Consist of central cup and

peripheral neuroretinal rim

Macula temporally

Fovea 2.5mm-diameter, darker

Page 10: Optic fundus in clinical medicine

Uniform red to pink

Disc-pale pink

1.5 mm in diameter

Nasal margin slightly blurred

Vessels emanate from optic cup

Consist of central cup and

peripheral neuroretinal rim

Macula temporally

Fovea 2.5mm-diameter, darker

Page 11: Optic fundus in clinical medicine

Uniform red to pink

Disc-pale pink

1.5 mm in diameter

Nasal margin slightly blurred

Vessels emanate from optic cup

Consist of central cup and

peripheral neuroretinal rim

Macula temporally

Fovea 2.5mm-diameter, darker

Page 12: Optic fundus in clinical medicine

Uniform red to pink

Disc-pale pink

1.5 mm in diameter

Nasal margin slightly blurred

Vessels emanate from optic cup

Consist of central cup and

peripheral neuroretinal rim

Macula temporally

Fovea 2.5mm-diameter, darker

Page 13: Optic fundus in clinical medicine

Uniform red to pink

Disc-pale pink

1.5 mm in diameter

Nasal margin slightly blurred

Vessels emanate from optic cup

Consist of central cup and

peripheral neuroretinal rim

Macula temporally

Fovea 2.5mm-diameter, darker

Page 14: Optic fundus in clinical medicine

Tygroid fundus

Deeply pigmented choroid

Choroidal vessels are seen

Polygonal pigmented areas in between

Page 15: Optic fundus in clinical medicine
Page 16: Optic fundus in clinical medicine

Dot haemorrhages Deep within the retina

Leakage of capillaries, venules

Common in diabetes

Flame haemorrhages Superficial nerve fibre layer

Leakage of capillaries, venules

that are ischemic or, in the case of veins, under high pressure

Boat haemorrhages (pre-retinal) Interface between retina & vitreous

Sub macular h‟ge, Preretinal h‟ge, Retinal h‟ge

Page 17: Optic fundus in clinical medicine

Dot haemorrhages Deep within the retina

Leakage of capillaries, venules

Common in diabetes

Flame haemorrhages Superficial nerve fibre layer

Leakage of capillaries, venules

that are ischemic or, in the case of veins, under high pressure

Boat haemorrhages (pre-retinal) Interface between retina & vitreous

Sub macular h‟ge, Preretinal h‟ge, Retinal h‟ge

Page 18: Optic fundus in clinical medicine

Dot haemorrhages Deep within the retina

Leakage of capillaries, venules

Common in diabetes

Flame haemorrhages Superficial nerve fibre layer

Leakage of capillaries, venules

that are ischemic or, in the case of veins, under high pressure

Boat haemorrhages (pre-retinal) Interface between retina & vitreous

Sub macular h‟ge, Preretinal h‟ge, Retinal h‟ge

Page 19: Optic fundus in clinical medicine

Dot haemorrhages Deep within the retina

Leakage of capillaries, venules

Common in diabetes

Flame haemorrhages Superficial nerve fibre layer

Leakage of capillaries, venules

that are ischemic or, in the case of veins, under high pressure

Boat haemorrhages (pre-retinal) Interface between retina & vitreous

Sub macular h‟ge, Preretinal h‟ge, Retinal h‟ge

Page 20: Optic fundus in clinical medicine

Dot haemorrhages Deep within the retina

Leakage of capillaries, venules

Common in diabetes

Flame haemorrhages Superficial nerve fibre layer

Leakage of capillaries, venules

that are ischemic or, in the case of veins, under high pressure

Boat haemorrhages (pre-retinal) Interface between retina & vitreous

Sub macular h‟ge, Preretinal h‟ge, Retinal h‟ge

Page 21: Optic fundus in clinical medicine

Dot haemorrhages Deep within the retina

Leakage of capillaries, venules

Common in diabetes

Flame haemorrhages Superficial nerve fibre layer

Leakage of capillaries, venules

that are ischemic or, in the case of veins, under high pressure

Boat haemorrhages (pre-retinal) Interface between retina & vitreous

Sub macular h‟ge, Preretinal h‟ge, Retinal h‟ge

Page 22: Optic fundus in clinical medicine

Hard exudate

Deep yellow with sharp margins

Often circinate

Leakage from pre-capillary arterioles

DM, HTN, VHL disease, radiation

„Macular star‟

Soft exudate(cotton wool spot)

Fluffy gray-white, near optic disc

Retinal nerve fiber layer microinfarction

HTN, DM, connective tissue disease,HIV

Page 23: Optic fundus in clinical medicine

Hard exudate

Deep yellow with sharp margins

Often circinate

Leakage from pre-capillary arterioles

DM, HTN, VHL disease, radiation

„Macular star‟

Soft exudate(cotton wool spot)

Fluffy gray-white, near optic disc

Retinal nerve fiber layer microinfarction

HTN, DM, connective tissue disease,HIV

Page 24: Optic fundus in clinical medicine

Hard exudate

Deep yellow with sharp margins

Often circinate

Leakage from pre-capillary arterioles

DM, HTN, VHL disease, radiation

„Macular fan‟

Soft exudate(cotton wool spot)

Fluffy gray-white, near optic disc

Retinal nerve fiber layer microinfarction

HTN, DM, connective tissue disease,HIV

Page 25: Optic fundus in clinical medicine

White centered retinal haemorrhages

CWS surrounded by h‟mage

CWS- ischaemic axons

H‟maghe- precapillary arterioles

Sub acute bacterial endocarditis

Leukaemia

Diabetes

Page 26: Optic fundus in clinical medicine

Deposition in ganglion cell layer

Thickening & loss of transparency of retina

Foveola-ganglion cells absent, thin, so contrast

Sphingolipidoses

Central retinal artery occlusion

Berlins edema

Page 27: Optic fundus in clinical medicine

Crack like dehiscence in brusch‟ membrane

Degenerative process combined with calcium deposition

Linear reddish brown lesion

Lies beneath normal blood vessels

“Pseu d‟orange”

Salmon spots, optic nerve drusen

Pseudoxanthoma elasticum, EDS

Paget‟s, Hemoglobinopathies

Page 28: Optic fundus in clinical medicine

Papillopheblitis (optic disc vasculitis)Affects healthy individuals <50

Disc edema, cotton wool spots

Venous dilatation and tortousity

Retinal haemorrhages

Retinal vasculitisOccurs in sarcoidosis, Behcet‟s disease,

Multiple sclerosis, idiopathic

Extremely rare in lupus

Perivenous lymphocytic infiltration (sheathing)

Page 29: Optic fundus in clinical medicine

Diffuse retinal dystrophy(rods)

Classic clinical triadArteriolar attenuation

Retinal bone-spicule pigmentation

Waxy disc pallor

Starts at mid periphery

Maculopathy

Associations Bassen-Kornzwieg syndrome,

Refsum‟s disease, Kearn-sayresyndrome , Usher‟s syndrome Muchopolysaccharidoses, Lauren‟s moon biedel syndrome, Friederischataxia

Page 30: Optic fundus in clinical medicine

Attempt at vascularising ischaemic tissue

Lacks bifurcating pattern

Bleed spontaneously

Diabetic retinopathy

Retinal vein occlusion

Radiation

Sickle cell retinopathy

Retinopathy of prematurity

Page 31: Optic fundus in clinical medicine

Separation of sensory retina from pigment epithelium

Rhegmatogenous RD

Non-rhegmatogenous RD Tractional- PDR, ROP, sickle cell

retinopathy, penetrating posterior segment trauma

Exudative- choroidal tumours, exophytic retinoblastoma, haradadisease, posterior scleritis, subretinalneovascularisation, severe hypertension

Elevated sheath of retinal tissue with folds

Page 32: Optic fundus in clinical medicine

Separation of sensory retina from pigment epithelium

Rhegmatogenous RD

Non-rhegmatogenous RD Tractional- PDR, ROP, sickle cell

retinopathy, penetrating posterior segment trauma

Exudative- choroidal tumours, exophytic retinoblastoma, haradadisease, posterior scleritis, subretinalneovascularisation, severe hypertension

Elevated sheath of retinal tissue with folds

Page 33: Optic fundus in clinical medicine
Page 34: Optic fundus in clinical medicine

Atherosclerosis, embolism

Retina appears white

Attenuation of arteries and veins

Cherry red spot

Investigate for

Valvular heart disease, endocarditis, mural thrombi, Carotid artery disease, systemic vasculitis, hematological disorders

Page 35: Optic fundus in clinical medicine

Cholesterol Fibrinoplatelet Calcific

(Hollenhorst plaques)

Page 36: Optic fundus in clinical medicine

Atherosclerosis, embolism

Retina appears white

Attenuation of arteries and veins

Cherry red spot

Investigate for

Valvular heart disease, endocarditis, mural thrombi, Carotid artery disease, systemic vasculitis, hematological disorders

Page 37: Optic fundus in clinical medicine

Atherosclerosis, embolism

Retina appears white

Attenuation of arteries and veins

Cherry red spot

Investigate for

Valvular heart disease, endocarditis, mural thrombi, Carotid artery disease, systemic vasculitis, hematological disorders

Cattle-trucking

Page 38: Optic fundus in clinical medicine

Embolism, periarteritis

Retinal cloudiness corresponding to the areas of ischemia

Narrowing of arteries and veins

One or more emboli may be present

Page 39: Optic fundus in clinical medicine

Present in 20% of population

It may be isolated, combined CRVO, combined AION

Localised cloudiness- macula and papillomacular bundle

Page 40: Optic fundus in clinical medicine

Occlusion of short posterior ciliary arteries

Disc is pale

Diffuse or sectoral edema

Splinter shaped h‟mages

„Pseudo-Foster kennedy syndrome‟

Page 41: Optic fundus in clinical medicine

Giant cell arteritis

Cotton wool spots are uncommon

Cilioretinal artery occlusion

Central artery occlusion

Page 42: Optic fundus in clinical medicine

EtiologyArteriosclerosis

Increasing age

Hypertension

Diabetes mellitus

Blood dyscrasiasis

Periphlebitis

Raised intraocular tension

Page 43: Optic fundus in clinical medicine

Dilatation & tortousity of all branches of CRV

Retinal h‟age- superficial & deep throughout

“Blood and thunder”

Cotton wool spots

Optic disc edema

Macular edema

Page 44: Optic fundus in clinical medicine

Venous dilatation and tortousity peripheral to the site of occlusion

Hemorrhages

Retinal edema

Cotton wool spots

Neovascularisation

Page 45: Optic fundus in clinical medicine

Most common cause of legal blindness in 20-65 yrs

Type 1>Type 2 (40% , 20%)

Risk factorsDuration of diabetes

Poor metabolic control

Pregnancy

Hypertension

Nephropathy

Smocking

Obesity

Hyperlipidaemia

Page 46: Optic fundus in clinical medicine

Micro vascular occlusion Microvascular leakage

Page 47: Optic fundus in clinical medicine

Eva kohner‟s classification

Non-proliferative diabetic retinopathy

Pre-proliferative diabetic retinopathy

Proliferative diabetic retinopathy

Page 48: Optic fundus in clinical medicine

Micro aneurysms(earliest lesion)

Hard exudates

Retinal edema

Haemorrhages

Page 49: Optic fundus in clinical medicine

Cotton wool spots

Intra retinal micro vascular abnormalities(IRMA)

Venous changes

Dilatation, looping

Beading, segmentation

Arterial changes

Narrowing, occlusion

Silver wiring

Dark blot haemorrhages

Page 50: Optic fundus in clinical medicine

Involvement of fovea

Perifoveal hard exudates

Dark blot hemorrhages

Page 51: Optic fundus in clinical medicine

Neovascularisation

Venous looping

Venous beading

NVD

NVE

Page 52: Optic fundus in clinical medicine

NVD NVE

Page 53: Optic fundus in clinical medicine

Primary response to HTN- vasoconstriction

Narrowing depend on pre-existing sclerosis

Narrowing seen in its pure form only in young individuals

Sustained HTN-inner BRB disrupted

Increased vascular permeability

Narrowing and sclerosis suggests duration of hypertension

Page 54: Optic fundus in clinical medicine

GRADE 1

Generalised arteriolar narrowing

GRADE2

Exaggeration of light reflex

AV crossing changes(Salus sign)

Page 55: Optic fundus in clinical medicine

GRADE 1

Focal arteriolar narrowing

GRADE2

Exaggeration of light reflex

AV crossing changes(Salus sign)

Page 56: Optic fundus in clinical medicine

GRADE 3

Prominent AV changes (Bonnet, Gunn signs)

Retina edema, CWS

Flame h‟mages

GRADE 4

Features of grade 3

Papilloedema

Page 57: Optic fundus in clinical medicine

Grade 0

Grade 1Grade 4

Grade 2Grade 3

Page 58: Optic fundus in clinical medicine

Rare, occurs in hypertensive crisis

„Elschnig spots‟

„Siegrist streaks‟

Exudative retinal detachment

Page 59: Optic fundus in clinical medicine

Creamy appearance of the vessels in the posterior pole and peripheral area

Triglycerides >2500mg/dl

Page 60: Optic fundus in clinical medicine

Micro vascular occlusion and ischemia

Severe head trauma, chest compression injury, Embolism, a/c pancreatitis, carcinoma, connective tissue diseases,

Lymphoma, TTP, Bone marrow transplantation

Multiple superficial white retinal patches

Superficial pericapillaryhaemorrhages

Page 61: Optic fundus in clinical medicine
Page 62: Optic fundus in clinical medicine

Sickle cell anaemia & Sickle cell thalassemia are associated severe ocular manifestations

Proliferative changes

Seafan neovascularisation

Haemorrhages

Page 63: Optic fundus in clinical medicine

STAGING

1. Peripheral arteriolar occlusion

2. Peripheral AV anastomosis

3. Sprouting new vessels

4. Vitreous haemorrhage

5. Retinal detachment

1

24

5

3

Page 64: Optic fundus in clinical medicine

Venous tortousity

Silver wiring of arterioles

„Salmon patches‟

„Black sunbursts‟

Macular depression sign

Peripheral retinal holes

Artery & vein occlusion

Angioid streaks

Page 65: Optic fundus in clinical medicine

Venous tortousity

Silver wiring of arterioles

„Salmon patches‟

„Black sunbursts‟

Macular depression sign

Peripheral retinal holes

Artery & vein occlusion

Angioid streaks

Page 66: Optic fundus in clinical medicine

Rarely diagnostic importance

Duration &type don‟t influence

Pale fundus

Haemorrhages

Cotton wool spots

Roth spot

Venous tortousity-related severity of anemia

Page 67: Optic fundus in clinical medicine

More common in a/c leukaemia

Primary- infiltration

Secondary- anemia, thrombocytopaenia, hyperviscosity, infection

Superficial haemorrhages

Roth spot

Cotton wool spot

Page 68: Optic fundus in clinical medicine

Peripheral retinal vascularisation

Pigment epitheliopathy- ‛leopard spot‟

Page 69: Optic fundus in clinical medicine

Venous dilatation

Segmentation

Venous tortousity

Retinal haemorrhages

Page 70: Optic fundus in clinical medicine

Viral

CMV

HIV

Rubella

Bacterial

Tuberculosis

Syphilis

Parasitic

Toxoplasmosis

Fungal

Page 71: Optic fundus in clinical medicine

Most common ocular infection in AIDS

Indolent retinitis

Starts in the periphery

Mild granular opacification

Fulminating retinitis

Dense white opacification

Vasculitis, mild vitritis

Hemorrhages

Extension along blood vessels

Involve optic nerve head

Page 72: Optic fundus in clinical medicine

60% of AIDS patients

Retinal microangiopathy

Multiple cotton wool spots

Non infectious

Page 73: Optic fundus in clinical medicine

Salt & pepper retinopathy, most marked at macula

Disc & vessels normal

Pigmentery disturbance at posterior pole

Optic neuritis

Page 74: Optic fundus in clinical medicine

Intractable chronic uveitis

Focal/multi focal choroiditis

Choroidal granuloma

Periphlebits

Panuveitis

Page 75: Optic fundus in clinical medicine

Quiscent Bilateral/unilateral healed chorio

retinal scars

Reactivation retinochoroiditis Adjacent to old scar

(satellite lesion)

Vasculitis,

Severe vitritis

(headlight in the fog‟ appearance)

Papillitis (secondary to juxtapapillary retinitis)

Atypical lesions

Page 76: Optic fundus in clinical medicine

Quiscent Bilateral/unilateral healed chorio

retinal scars

Reactivation retinochoroiditis Adjacent to old scar

(satellite lesion)

Vasculitis,

Severe vitritis

(headlight in the fog‟ appearance)

Papillitis (secondary to juxtapapillary retinitis)

Atypical lesions

Page 77: Optic fundus in clinical medicine

Quiscent Bilateral/unilateral healed chorio

retinal scars

Reactivation retinochoroiditis Adjacent to old scar

(satellite lesion)

Vasculitis,

Severe vitritis

(headlight in the fog‟ appearance)

Papillitis (secondary to juxtapapillary retinitis)

Atypical lesions

Page 78: Optic fundus in clinical medicine
Page 79: Optic fundus in clinical medicine

Retinal periphlebitis

„Candle wax drippings‟

Branch retinal vein occlusion

Cotton ball vitreous opacities

Haemorrhages,

Granulomas

Optic nerve edema and granuloma

Page 80: Optic fundus in clinical medicine

Optic disc granuloma Retinal granuloma ‟Landers sign‟

Page 81: Optic fundus in clinical medicine

Optic disc granuloma Retinal granuloma ‟Landers sign‟

Page 82: Optic fundus in clinical medicine

A/c recurrent Hypopyon uveitis

Retinitis- superficial infiltrates

Retinal vasculitis

Periphlebitis & periarteritis

Vascular occlusion

Vascular leakage

Optic disc edema

Retinal exudation

Vitritis

Page 83: Optic fundus in clinical medicine

Optic disc edema

Multifocal detachments of the sensory retina

Exudative retinal detachment

Numerous, residual, small, atrophic scars(‛sunset glow‟ fundus)

Page 84: Optic fundus in clinical medicine

No typical features

Retinopathy

Haemorrhages

Cotton wool spots

Vascular occlusions

Page 85: Optic fundus in clinical medicine
Page 86: Optic fundus in clinical medicine

Hyaline like calcific material within optic disc

Often bilateral, 0.3%

Buried drusen

Elevated disc, scalloped margin

No physiological cup

No hyperaemia

Vessels not obscured

Venous pulsation present

Exposed drusen

Waxy pearl like irregularities

Page 87: Optic fundus in clinical medicine

Hyaline like calcific material within optic disc

Often bilateral, 0.3%

Buried drusen

Elevated disc, scalloped margin

No physiological cup

No hyperaemia

Vessels not obscured

Venous pulsation present

Exposed drusen

Waxy pearl like irregularities

Page 88: Optic fundus in clinical medicine

Hyaline like calcific material within optic disc

Often bilateral, 0.3%

Buried drusen

Elevated disc, scalloped margin

No physiological cup

No hyperaemia

Vessels not obscured

Venous pulsation present

Exposed drusen

Waxy pearl like irregularities

Page 89: Optic fundus in clinical medicine

Incomplete closure of the choroid fissure

Discrete, focal, glistening, white,bowl shaped excavation

Disc may enlarged

Retinal vasculature normal

Complication- RD

Trisomy 13, 18, 22

CHARGE

Page 90: Optic fundus in clinical medicine

Visual acuity very poor

Enlarged disc with funnel shaped excavation

Central core -whitish glial tissue

Spokes of wheel appearance

Complication- RD

Frontonasal dysplasia

Neurofibromatosis type-2

Page 91: Optic fundus in clinical medicine

Myelination extend to retina

Don‟t interfere with vision

Larger & denser than CWS

Always connected to optic disc

No overlying vitreous haze

Page 92: Optic fundus in clinical medicine

Normal vertical cup-disc ratio 0.3 or less

Page 93: Optic fundus in clinical medicine

Inflammatory, infective or demyelinating process

Retrobulbar neuritis

Optic disc normal

Most common type in adult, MS

Papillitis

Hyperemia & edema of optic disc

Flame h‟mage

Neuroretinitis

Papiiltis with retinal nerve fibre layer inflammation

Macular star

Viral infection , cat scratch fever, syphilis

Page 94: Optic fundus in clinical medicine

Inflammatory, infective or demyelinating process

Retrobulbar neuritis

Optic disc normal

Most common type in adult, MS

Papillitis

Hyperemia & edema of optic disc

Flame h‟mage

Neuroretinitis

Papiiltis with retinal nerve fibre layer inflammation

Macular star

Viral infection , cat scratch fever, syphilis

Page 95: Optic fundus in clinical medicine

Inflammatory, infective or demyelinating process

Retrobulbar neuritis

Optic disc normal

Most common type in adult, MS

Papillitis

Hyperemia & edema of optic disc

Flame h‟mage

Neuroretinitis

Papiiltis with retinal nerve fibre layer inflammation

Macular star

Viral infection , cat scratch fever, syphilis

Page 96: Optic fundus in clinical medicine

Swelling of optic nerve head secondary to raised intracranial pressure

Early papilloedema

Optic disc- hyperemia & mild elevation

Disk margins indistinct

Loss of spontaneousvenous pulsation

Page 97: Optic fundus in clinical medicine

Established papilloedema

Hyperaemia of optic disc

Blurred, elevated margin

Obliterated cup

Venous engorgement

Flame shaped hemorrhages

Cotton wool spots

Hard exudates-‛macular fan‟

Page 98: Optic fundus in clinical medicine

Chronic papilloedema

Optic disc elevated and white ‛champagne cork appearance‟

Usual cause chronic elevated ICT

Corpora amylacea

Irreversible visual loss

Cotton wool spot & h‟mageabsent

Page 99: Optic fundus in clinical medicine

Retro laminar portion of optic nerve to lateral geniculate body

Lesion anterior to optic chiasma-unilateral

RB neuritis, hereditary, compressive lesions, toxic& nutritional optic neuropathy

Without antecedent swelling of optic disc

Pale flat disc, clear margins

Reduction in no. of small BV on the disc- „Kestenbaum sign‟

Atrophy may be diffuse/sectoral

Page 100: Optic fundus in clinical medicine

Retro laminar portion of optic nerve to lateral geniculate body

RB neuritis, hereditary, compressive lesions, toxic& nutritional optic neuropathy

Without antecedent swelling of optic disc

Lesion anterior to optic chiasma-unilateral

Pale flat disc, clear margins

Reduction in no. of small BV on the disc- „Kestenbaum sign‟

Atrophy may be diffuse/sectoral

Page 101: Optic fundus in clinical medicine

Preceded by swelling

Papilloedema, AION, Optic neuritis

Dirty grey slightly raised disc

Ill defined margins –gliosis

Sheathed vessels

Reduction in small vessels

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Page 103: Optic fundus in clinical medicine

Clinical opthalmology- Jack J.Kanski 5th Ed.

“The Eyes Have It”-University of Michigan

Harrison‟s Principles of internal medicine 16th Ed.

Parsons‟ Diseases of the Eye 20th Ed.

New England Journal of Medicine

Page 104: Optic fundus in clinical medicine