Definition
The miosis consists in the reduction of the pupillary diameter below 4 mm. This occurs physiologically to allow near vision or in response to a very intense light stimulus. However, the miosis can also be pathological or pharmacologically induced (eg pilocarpine and reserpine).
The pupil narrowing is observed in the paralysis of the sympathetic cervical system, in lesions of the eyeball or orbit, in cerebral hemorrhages and in some forms of encephalitis. Other pathological conditions that manifest themselves with miosis are neurological lesions of tabetic origin and traumas to the head, neck and spine.
Sometimes, the presence of point-like pupils is the consequence of intoxication from drugs or drugs (in particular, from opiates and derivatives, eg heroin or morphine overdose) or from toxic chemicals.
Possible Causes * of Miosis
- Headache
- Cerebral hemorrhage
- Encephalitis
- Stroke
- Iridocyclitis
- Cerebral ischemia
- Horner syndrome
- Uveitis
