Ento Key

Introduction The vitreous is a transparent extracellular gel consisting of collagen, soluble proteins, hyaluronic acid and water. Its total volume is approximately 4.0 ml. The few cells normally present in the…

Acquired Cataract Age-related cataract Subcapsular cataract Anterior subcapsular cataract lies directly under the lens capsule and is associated with fibrous metaplasia of the lens epithelium. Posterior subcapsular opacity lies just…

Anatomy The scleral stroma is composed of collagen bundles of varying size and shape that are not uniformly orientated as in the cornea, and so are not transparent. The inner…

Keratoplasty Introduction Corneal transplantation (grafting) refers to the replacement of diseased host corneal tissue by healthy donor cornea. A corneal graft (keratoplasty) may be partial-thickness (anterior or posterior lamellar) or…

Introduction Anatomy The skin ( Fig. 1.1A ) consists of the epidermis, dermis and related structures (adnexa). Fig. 1.1 Eyelid skin. (A) Normal skin is composed of keratinized stratified epithelium…

Introduction Anatomy The orbit is a pear-shaped cavity, the stalk of which is the optic canal ( Fig. 3.1 ). • The roof consists of two bones: the lesser wing…

Introduction Anatomy The conjunctiva is a transparent mucous membrane that lines the inner surface of the eyelids and the anterior surface of the globe, terminating at the corneoscleral limbus. It…

Introduction Definitions Dry eye occurs when there is inadequate tear volume or function, resulting in an unstable tear film and ocular surface disease. It is an extremely common condition, particularly…

Introduction Anatomy The lacrimal drainage system consists of the following structures ( Fig. 2.1 ): • The puncta are located at the posterior edge of the lid margin, at the…