User:Willy1018/沙盒/Miosis

Willy1018/沙盒/Miosis
同义词Myosis
Myosis due to opiate use.jpg
Myosis due to opiate英语opiate (codeine) use
读音
  • /maɪˈoʊ sɪs/
分类和外部资源

Miosis, or myosis, is excessive constriction of the pupil英语Pupillary response.[1][2][3][4] The term is from Ancient Greek μύειν mūein, "to close the eyes". The opposite condition, mydriasis, is the dilation of the pupil英语Pupillary response. Anisocoria英语Anisocoria is the condition of one pupil being more dilated than the other.

原因编辑

年齡编辑

  • Senile miosis (a reduction in the size of a person's pupil in old age)

疾病编辑

藥物编辑

Physiology of the photomotor reflex编辑

Light entering the eye strikes three different photoreceptors in the retina: the familiar rods and cones used in image forming and the more newly discovered photosensitive ganglion cells. The ganglion cells give information about ambient light levels, and react sluggishly compared to the rods and cones. Signals from photosensitive ganglion cells have multiple functions including acute suppression of the hormone melatonin, entrainment英语Entrainment (chronobiology) of the body's circadian rhythms and regulation of the size of the pupil.

The retinal photoceptors convert light stimuli into electric impulses. Nerves involved in the resizing of the pupil connect to the pretectal nucleus英语Pretectum of the high midbrain, bypassing the lateral geniculate nucleus英语lateral geniculate nucleus and the primary visual cortex. From the pretectal nucleus neurons send axons to neurons of the Edinger-Westphal nucleus whose visceromotor英语Motor neuron axons run along both the left and right oculomotor nerves. Visceromotor nerve axons (which constitute a portion of cranial nerve III, along with the somatomotor portion derived from the Edinger-Westphal nucleus) synapse on ciliary ganglion neurons, whose parasympathetic axons innervate the iris sphincter muscle, producing miosis.

參見编辑

參考資料编辑

  1. ^ Farlex medical dictionary citing:
  2. ^ Seidel, Henry M.; Jane W. Ball; Joyce E. Dains; G. William Benedict. Mosby's Guide to Physical Examination. Mosby. 2006-03-29. ISBN 978-0-323-03573-6.  已忽略未知参数|url-access= (帮助)
  3. ^ Farlex medical dictionary citing: Millodot: Dictionary of Optometry and Visual Science, 7th edition.
  4. ^ Farlex medical dictionary citing: Mosby's Medical Dictionary, 8th edition.
  5. ^ British Journal of Clinical Pharmacology. Relationship between sedation and pupillary function: comparison of diazepam and diphenhydramine. British Journal of Clinical Pharmacology. 27 Feb 2006, 61: 752–60. PMC 1885114 . PMID 16722841. doi:10.1111/j.1365-2125.2006.02632.x. 

外部連結编辑

分類
外部資源

Category:病征 Category:眼科