Basic Science of the Lens
IN THIS CHAPTER Additional content available online at ExpertConsult.com Definition A normally transparent intraocular structure whose function is to alter the pathway of light that has entered the eye to…
Herpes Simplex Keratitis
Definition Herpes simplex viral infection of the cornea. Key Features • Dendritic ulcer: classic feature of epithelial disease. • Focal endotheliitis (disciform keratitis): classic feature of stromal disease. Associated Features…
Bacterial Keratitis
Definition Corneal disease caused by bacterial organisms. Key Feature • Cellular infiltration of the corneal epithelium or stroma, corneal inflammation, and necrosis. Associated Features • Lid edema. • Conjunctival inflammation….
Keratoconus and Other Ectasias
Definition Corneal ectasia is a group of disorders affecting the shape of the cornea and include keratoconus, pellucid marginal corneal degeneration, post–refractive surgery corneal steepening, and keratoglobus. Key Features •…
Anterior Corneal Dystrophies
Definition Bilateral disorders, most of which are inherited, in which an abnormal substance accumulates primarily in the corneal epithelium. Key Features • Typically bilateral. • Progressive. • Involvement is anterior…
Acid and Alkali Burns
Definition Chemical exposure to the eye resulting in trauma ranging from mild irritation to severe damage of the ocular surface and anterior segment with permanent vision loss. Key Features •…
Corneal Anatomy, Physiology, and Wound Healing
Definition The cornea represents the transparent anterior wall of the globe. Key Features • The cornea, including the tear film, is the major refractive surface of the eye. • It…
Peripheral Ulcerative Keratitis
Definition Destructive inflammation of the peripheral cornea associated with corneal epithelial sloughing and keratolysis. Key Features • Peripheral corneal ulceration. • Unilateral or bilateral. • Progresses circumferentially and posteriorly and…
Parasitic Keratitis
Definition Corneal disease caused by protozoal organisms. Key Feature • Cellular infiltration of the corneal epithelium or stroma, corneal inflammation, and necrosis. Associated Features • Delay in diagnosis is common….
Fungal Keratitis
Definition Corneal disease caused by fungal organisms. Key Feature • Cellular infiltration of the corneal epithelium or stroma, corneal inflammation, and necrosis. Associated Features • Long-term corticosteroid use. • Trauma…
