Pterygia - IU Optometry · Pterygia • Etiology: triangular, fibrovascular, connective tissue...
Transcript of Pterygia - IU Optometry · Pterygia • Etiology: triangular, fibrovascular, connective tissue...
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Pterygia
• Etiology: triangular, fibrovascular, connectivetissue overgrowths of bulbar conjunctiva ontocornea; distribution of ultraviolet energy- heat,wind, dust, dry atmosphere,higher prevalencenearer the equator
• Usually horizontally,intrapalpebrally oriented withthe base peripheral and the apex over the cornea
• Asymptomatic to photphobia, tearing, FBsensation, decrease vision by with rule irregularastig.
• Slit lamp: horizontally located in palpebral
fissure, usually nasal side; a grayish, flat
avascular zone lies at apex: a pigment line,
(I.e. Stocker’s line) may be seen in advance
of pterygium; indications for activity are
epithelial staining, opacifications of
Bowman’s membrane, fleshiness and
thickness of vessels
• Treatment: surgical with mask recurrence
as high as 40%; surgical excision with B-
radiation less recurrence and topical
mitomycin C; wearing of eyeglasses to
reduce ultraviolet energy and hats,
conservative attitude toward surgery
• Pseudopterygium- a probe can be passed
between the mass and the globe
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Senile: flattening of vertical meridian,
thinning of periphery, lack of luster
• White Limbal Girdle of Vogt– Etiology: a degeneration found quite
frequently (60%) in patients over 45, innocuous
– Slit lamp: white, narrow, crescentic, irregular,chalky opacity in temporal and medial limbalareas of Bowman’s, in the interpalpebral zone,no vascularization, vision not affected; arcshape; may or may not be a clear interval
– Two types-- see chart
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Anterior Mosaic (Crocodile)
Shagreen
• Slit lamp: unknown, bilateral, polygonal,grayish-white opacities separated by cleartissue in the deep areas of the epithelium andBowman’s; usually located axially; visionusually not affected, appearance likened tocrocodile leather, most prominent centrally
• Anterior corneal mosaic pattern- NaFlstained cornea after applying pressure to thecornea through the lid
Posterior Crocodile Shagreen
• Slit lamp: bilateral, grayish-white opacities
in deep stroma and Descemet’s which
appear as small polygonal patches of
various sizes separated by dark regions
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Cornea Farinata
• Etiology: may be transmitted as an autosomal
dominant trait or may be a manifestation of senile
changes
• Slit lamp: small gray-white, tiny, dustlike dots
and flecks deep in the stroma or pre-Descemet’s
zone, no vascularization; axially diffuse or annular
distribution; farinata refers to “flour-like”
appearance of deposits, visually insignificant
Corneal Arcus Senilus
• Etiology: deposition of cholesterol esters,
triglycerides, and phospholipids in peripheral
stromal cornea; a bilateral, hazy ring in the
peripheral cornea, may be associated with
abnormalities in blood lipids (elevation of
cholesterol and LDLs), especially in younger
persons, risk factor for heart disease(order serum
lipid profile), unilateral suggest vascular occlusion
on side without arcus, most often age related
• Slit lamp: complete or incomplete
perilimbal yellow-white, hazy opacity; clear
perilimbal zone, lipid first noted in
Descemet’s membrane and then Bowman’s
layer, deposits appear first in the inferior
and then the superior and eventually
encircle the entire cornea
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Hudson Stahli line
• Yellowish brown, narrow, horizontal, single
line of pigmentation seen between the lower
pupil margin and inferior limbus
• Iron deposition occurs with aging, due to
disturbed, epithelial turnover
Descemet’s striae
• Etiology: aging change in the Descemet’s
membrane in an otherwise normal cornea
• Slit lamp: small, fine, linear (usually
vertically oriented) striations which are not
large enough to cause irregularities of
posterior cornea
Hassall-Henle Bodies
• Etiology: peripheral, localized, nodular
thickening of the Descemet’s membrane in
the periphery; considered to be
physiological aging changes
• Slit lamp: same as corneal guttata but are
peripheral; specular reflection as small
circular, dark areas within the normal
endothelial mosaic
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Dellen
• Etiology: thinning of cornea or sclera due
to tear film abnormalities and dryness
• Slit lamp: localized thin spots that occur in
limbus adjacent to acute elevations of the
conjunctiva