Few notes from K&C on the eye
Common disorders of the eye:
- Refractive errors: due to shape of globe = myopic (too much refraction = short sighted) / hypermetropic (too little = long sighted)
- Disorders of the lids: entropion (lid margin rolled inwards), ectropion (rolled outwards), dacrocystitis (inflammed lacrimal sac), blepharitis (blockage of meibomian galngs leading to swelling of lid = chalazion)
- Bacterial (only 5% of all conjunctivitis) – often gonococcal, H. influenzae, S. pneumoniae, S. Aureus, moraxella, chlamydia.
- Viral: highly contagious, HSV, molluscum contagiosum
- Allergic: seasonal, perennial, vernal, atopic and giant papillary
Corneal disorders: abrasions, foreign body, trauma, keratitis (general corneal inflammation)
Plus: cataracts, glaucoma, uveitis, disorders of retina.
- The white of the eye = sclera, is covered by a clear layer = conjunctiva
- The pink gooey bit in the medial part of eye = caruncle
- Coloured part of eye = iris, covered over by a clear layer = cornea
- Average diameter of human eye = 24mm
- The cornea is 12mm x 11mm and provides 78% of the focusing power of the eye