Keywords: Chapter 24, Eye & Skin

Acquired melanocytic nevus

A benign neoplastic proliferation of melanocytes. Their growth is symmetrical and well circumscribed and may be at the dermoepidermal junction, junctional, within the dermis, dermal, or a combination of both.
Actinic keratosis
An in situ proliferation of neoplastic squamous epidermal cells caused by ultraviolet light. These may spread within the epidermis, stop growing, recede, or progress to invasive squamous cell carcinoma.
Allergic contact dermatitis
A T-lymphocyte mediated reaction to an allergen present on the epidermal surface. .
Alopecia
Hair loss.
Angioedema
An urticarial reaction involving the deep dermal and or subcutaneous tissue.
Annular
Ring like.
Basal cell carcinoma
An invasive neoplastic proliferation of epidermal basaloid cells which grows down into the dermis and beyond. Although it almost never metastasizes, it can kill a patient by direct extension. Basal cell carcinoma is considered benign by some definitions and malignant by others.
Blister
A fluid filled cavity.
Bulla
A blister greater than 0.5 cm in diameter.
Bullous Keratopathy:
Corneal epithelium blister formation, usually due to excessive fluid pressure, edema, of the corneal stroma which in turn is usually caused by dysfunction of the corneal endothelial layer.
Cataracts:
Opacity of the lens.
Corneal Dystrophy:
A heterogeneous collection of congenital and acquired degenerative diseases of the cornea causing partial or total opacity.
Diabetic Retinopathy:
A series of events involving the retinal capillaries which eventually leads to focal retinal ischemia, hemorrhages, neovascularization and retinal detachment.
Discoid
Disk shaped.
Eczema
An erythematous, papulovesicular, edematous, Oozing lesion.
Elevated Intraocular Pressure:
Intraocular pressure is balanced against the strength of the lamina cribrosa in the pathogenesis of glaucoma.
Erythema multiforme
An acute, self limited dermatitis usually producing a rased erythematous lesion. When severe large bullae can occur.
Excoriation
Scratch or abrasion causing removal of part of the epidermis.
Glaucoma, Closed And Open Angle
Refers to the open or closed channel through the trabecular meshwork with the implied effect on intraocular pressure.
Herpes simplex
Herpes simplex virus (HSV) infection, usually of skin and mucous membranes. Latent infection may remain in sensory nerve cells.
Herpes Simplex Keratitis:
Infection of the cornea with herpesvirus, usually type 1, it is the most common cause of central corneal opacity in the USA.
Herpetiform
Small grouped lesions, in the fashion of herpes simplex vesicles.
Hypertensive Retinopathy:
Effects of hypertension on the retina ultimately leading to focal infarcts, retinal hemorrhage, neovascularization and retinal detachment.
Impetigo
Superficial bacterial infection of the skin, usually staphylococcal or streptococcal.
Iritis:
A special case of uveitis, the iris is part of the uveal tissues. The acute danger is involvement of the posterior uvea and then the retina. The chronic sequela is closure of the anterior chamber angle.
Lamina Cribrosa:
The fenestrated extension of the sclera across the head of the optic nerve. Posterior bowing of this in glaucoma causes constriction of optic nerve fibers.
Lentigo
A focal area of mild, benign, epidermal hyperplasia. It is usually hyperpigmented but the melanocytes are normal.
Leukocytoclastic vasculitis
A circulating immune complex mediated vasculitis, Type III hypersensitivity, primarily of venules. Inflammatory injury causes fibrin exudation and red cell extravasation.
Lupus erythematosus
This may occur as a disease of the skin alone, discoid lupus, or as part of systemic lupus erythematosus; the pathology is the same in both. The patients are photosensitive, the erythematous rash typically occurs on sun exposed skin. Lymphocytes migrate into the epidermis and there is vacuolar degeneration of the basal cells and epidermal atrophy.
Macular Degeneration:
Degeneration of the foveal retina, and therefore loss of central vision, most commonly seen with advanced age.
Macule
Flat area of altered coloration.
Melanoma
A malignant proliferation of melanocytes. Their growth is characteristically irregularly pigmented, asymmetrical and poorly demarcated. This malignancy metastasizes readily and does not respond well to any form of therapy once it has metastasized.
Nevus
In the strict sense, a hamartoma of skin; with respect to melanocytes, a benign neoplasm.
Nummular
Coin shaped.
Optic Atrophy:
Atrophy of optic nerve fibers, papilledema and glaucoma are important causes.
Papilledema:
Optic disc edema or swelling of optic nerve fibers in front of the lamina cribrosa, increased intracranial pressure, venous occlusion, malignant hypertension, severe acute glaucoma are among the causes.
Papule
An elevated area less than 0.5 cm in diameter.
Pemphigoid
A Type II autoimmune reaction to epidermal basement membrane resulting in a subepidermal blister.
Pemphigus vulgaris
An intraepidermal bullous disease caused by an autoantibody to the epidermal cell surface.
Plaque
An elevated area greater than 0.5 cm in diameter.
Psoriasis
A chronic, frequently familial disease characterized by erythematous scaly plaques. Histological, epidermal squamous cell hyperplasia is the most striking feature.
Purpura
Hemorrhage into the skin.
Pustule
A papule containing a purulent exudate.
Retinal Detachment:
Separation of the retina from the uveal vascular bed. This separates the photoreceptor cells from their supply of oxygen etc.
Retinoblastoma:
An ocular malignant neoplasm of the retina, usually arise in the first 2 years of life, it is the most form of intraocular malignancy in children.
Scabies
Epidermal infestation by the mite Sarcoptes scabiei.
Scale
Keratinaceous debris on the surface of the skin.
Seborrheic keratosis
A raised, sharply demarcated, brown pigmented, papule or plague which result from proliferation of squamous basaloid cells which sit on top of and do not invade the dermis.
Squamous cell carcinoma
A malignant neoplasm of squamous cells. In the white population, squamous cell carcinoma of the skin is associated with prolonged exposure to ultraviolet light and these neoplasms are slow to metastasis even after becoming invasive.
Tinea
A superficial fungal infection, in most cases involves only the cornified epidermis.
Trabecular Meshwork:
The sive like portion of the ocular anterior chamber through which aqueous humor exits and which controls intraocular pressure.
Urticaria
A type I hypersensitivity reaction caused by granule release by dermal mast cell or basophils. This results in dilation of the dermal vessels and transient erythema and edema. This may be triggered by an a circulating antigen or, in some patients, by mild trauma.
Uveal Melanoma:
A malignant ocular neoplasm of uveal melanocytes, most commonly seen in adults it is the most common form of intraocular malignancy in adults.
Uveitis:
Inflammation, often infection, of the iris and/or the vascular tissue just behind the retina. The retina, and therefore vision, is often directly involved and damaged.
Verruca Vulgaris (Wart)
A papillomavirus induced papule or plaque resulting from focal epidermal hyperplasia.
Verrucae (Warts)
A benign epidermal neoplasms induced by human papilloma virus (HPV)
Vesicle
A blister less than 0.5 cm in diameter.