Ento Key

Bacterial keratitis Pathogenesis • Pathogens: most common are (a) Pseudomonas aeruginosa , (b) S. aureus , and (c) streptococci. • Risk factors: (a) contact lens wear, (b) trauma, and (c)…

Age-related macular degeneration Introduction • Definition: degeneration affecting the macula; characterized by drusen and RPE changes, and sometimes CNV. • Classification: non-exudative (‘dry’)—most common, and exudative (‘wet’); the latter is…

Eyelid trauma Periocular haematoma • A ‘black eye,’ consisting of a haematoma (focal collection of blood) and/or periocular ecchymosis (diffuse bruising) and oedema, is a very common result of blunt…

Ocular hypertension Diagnosis • Normal IOP: mean IOP in the general population is 16 mm Hg; two standard deviations to either side of this gives a ‘normal’ IOP range of 11–21 mm…

Generalized photoreceptor dystrophies Retinitis pigmentosa Genetics: Typical retinitis pigmentosa (RP) is a group of retinal dystrophies initially mainly affecting the rod photoreceptor cells and subsequently cones (rod–cone dystrophy). It can…

Definitions • Retinal detachment (RD): separation of the neurosensory retina (NSR) from the RPE, with the accumulation of subretinal fluid (SRF). • Rhegmatogenous RD: occurs when a full-thickness defect in…

Amblyopia Definition: unilateral, or rarely bilateral, subnormal best corrected VA caused by form vision deprivation and/or abnormal binocular interaction, for which there is no identifiable pathology of the eye or…

Cornea Vortex keratopathy (cornea verticillata) • Signs: (a) fine greyish or golden-brown opacities in the inferior corneal epithelium, (b) progressing to a whorl-like pattern that originates from a point below…

Acquired cataract Age-related cataract • Subcapsular ( Fig. 9.1 ): (a) anterior lies directly under the lens capsule, and (b) posterior lies just in front of the posterior capsule and…

Bacterial conjunctivitis Acute bacterial conjunctivitis Pathogenesis: direct eye contact with infected secretions; most common isolates are S. pneumoniae , S. aureus , H. influenza , and Moraxella catarrhalis ; uncommon…