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1、Fundoscopic examination,Fundoscopic Examination,Window to the blood vessels Prerequisites- Good ophthalmoscope A large pupil A still field,Fundoscopic Examination,Diminish illumination in the room( to overcome light reflex) Instruct the pt to look at a distant point, which is clearly defined( to ove
2、rcome accomodation and keeping the eye still) Rt eye for examining rt fundus, lt eye for left fundus,Fundoscopic Examination,First find the optic disc Colour Edges Optic cup Nasal blurring, temporal pallor- Normal Vessels CRA- superior and inferior branches, nasal & temporal br-four prominent arteri
3、al trunks emanating from the disc Vns are larger and darker Arteries are lighter and narrower than vns and often have a central reflecting line silver-wire appearance Point of crossing of arteries and vns Haemorrhage and exudates Macula, Peripheral retina,Optic disc,Optic cup,Vein,Arterioles,Fovea,N
4、ormal Ocular Fundus,Fundoscopic Examination,Cup to Disk Ratio Diameter of the cupped region of the optic nerve headdivided by the diameter of the optic nerve head.Normal is 0.3-0.5. Abnormal values are higher and are associated withglaucoma,C/D = 0.6,Cotton Wool Spots,Cotton wool spots result from o
5、cclusion of retinal pre-capillary arterioles supplying the nerve fibre layer with concomitant swelling of local nerve fibre axons. Also called “soft exudates“ or “nerve fibre layer infarctions“ they are white, fluffy lesions in the nerve fibre layer. Papilloedema, HTN, PAN, retinal embolism, severe
6、anaemia,Hard exudates,Hard exudates ( Intra-retinal lipid exudates ) are yellow deposits of lipid and protein within the retina. Accumulations of lipids leak from surrounding capillaries and microaneurysms, they may form a circinate pattern. Hyperlipidemia may correlate with the development of hard
7、exudates.,Papilledema- Definition,Swelling of optic disc Arbitrarily, the term has been reserved for the passive disc swelling associated with raised ICP Usually bilateral, although it may be asymmetrical,Causes of papilledema (Raised ICP),Clinical Features of Papilledema,Usually bilateral but may b
8、e unilateral or asymmetric Usually preserved visual acuity and color vision early May have transient visual loss lasting seconds (obscurations of vision) Visual field defects Enlarged blind spot Generalized constriction Glaucomatous-like defects Eventual peripheral constriction, especially nasally N
9、o afferent pupillary defect,Papilledema showing blurred disc margins and dilated tortuous vessels,Comprehensive Ophthalmology: Khurana,Early papilledema,Minimal disc hyperemia with capillary dilation Early opacification of nerve fiber layer (peripapillary retina loses its superficial linear and curv
10、ilinear light reflex and appears red without luster) Early swelling of disc Absence of venous pulsations Peripapillary retinal nerve fiber layer hemorrhage,Fully developed papilledema,Engorged and tortuous retinal veins May have splinter hemorrhages at or adjacent to the disc margin Disc surface gro
11、ssly elevated Surface vessels become obscured by now opaque nerve fiber layer May have cotton wool spots Patons lines (circumferential retinal folds) or choroidal folds Hemorrhage and exudates In acute cases (e.g., subarachnoid hemorrhage), subhyaloid hemorrhages may occur that may break into vitreo
12、us (Tersons syndrome),Frisen Papilledema Grading System Stage 1,Obscuration of the nasal border of the disc No elevation of the disc borders Disruption of the normal radial nerve fiber layer (NFL) arrangement with grayish opacity accentuating nerve fiber bundles Normal temporal disc margin Subtle gr
13、ayish halo with temporal gap,C-shaped halo with a temporal gap,Frisen Papilledema Grading System Stage 2,Obscuration of all borders Elevation of nasal border Complete peripapillary halo,Halo becomes circumferential,Frisen Papilledema Grading System Stage 3,Obscuration of all borders Elevation of all
14、 borders Increased diameter of the optic nerve head Obscuration of one or more segments of major blood vessels leaving the disc Peripapillary haloirregular outer fringe with finger-like extensions,Loss of major vessels as they leave the disc (arrow),Frisen Papilledema Grading System Stage 4,Elevatio
15、n of entire nerve head Obscuration of all borders Peripapillary halo Total obscuration on the disc of a segment of a major blood vessel,loss of major vessels ON THE DISC,Frisen Papilledema Grading System Stage 5,Dome-shaped protrusions representing anterior expansion of the optic nerve head Peripapi
16、llary halo is narrow and smoothly demarcated Total obscuration of a segment of a major blood vessel may or may be present Obliteration of the optic cup,Grade IV plus partial or total obscuration of all vessels of the disc,Pseudopapilledema,Optic nerve drusen Medullated nerve fiber Hypermetropic disc Congenital anomalous elevation,Optic atrophy - Definition,Optic nerve shrinkage from any process that produce degeneration of axons in the ant.visual (Retinogeniculate) pathway,
