Health encyclopaedia

Health encyclopaedia - Alphabetical Topic List

Diagnosis of Short-sightedness

Diagnosis of myopia is done using a simple vision test, using a standardised eye chart. Mirrors are used to reflect the chart so it appears to be 20ft. away. Each line of the eye chart is assigned a notation in the form of a fraction that represents the individual’s visual ability.

The numerator is the distance in feet the patient is from the eye chart.   The denominator represents the distance an eye with perfect vision can read the same line.   Therefore if a person, for example, can read the 20/40 line, they are able to see at 20 feet what a perfect eye could see at 40.

• SARSScabiesScarlet feverScarsSchizophreniaSciaticaScoliosisScurvySeasonal affective disorderSecond opinionSelf-injurySeptic shockSexual health clinicsSexually transmitted infectionsShinglesShort-sightednessSick building syndromeSickle-cell anaemiaSinusitisSjogren's syndromeSlapped cheek syndromeSleep apnoeaSlipped discSmear testSmoking (quitting)SnoringSore throatSpina bifidaSpinal muscular atrophySports injuriesSprainsSquintStaphylococcal infectionsSterilisationStillbirthStings, insectStings, marine creaturesStreptococcal infectionsStressStretch marksStrokeSubarachnoid haemorrhageSubdural haematomaSudden infant death syndromeSuicideSunburnSupraventricular tachycardiaSyphilis

  ---