Pterygia Etiology: triangular, fibrovascular, connective tissue overgrowths of bulbar conjunctiva onto cornea; distribution of ultraviolet energy- heat, wind, dust, dry atmosphere,higher prevalence nearer the equator Usually horizontally,intrapalpebrally oriented with the base peripheral and the apex over the cornea Asymptomatic to photphobia, tearing, FB sensation, decrease vision by with rule irregular astig. 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 1
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 limbal areas of Bowman s, in the interpalpebral zone, no vascularization, vision not affected; arc shape; may or may not be a clear interval Two types-- see chart 2
Anterior Mosaic (Crocodile) Shagreen Slit lamp: unknown, bilateral, polygonal, grayish-white opacities separated by clear tissue in the deep areas of the epithelium and Bowman s; usually located axially; vision usually not affected, appearance likened to crocodile leather, most prominent centrally Anterior corneal mosaic pattern- NaFl stained cornea after applying pressure to the cornea 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 3
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 4
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 5
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 6