Editing Amblyopia (section)

===Strabismus===
{{Further|Strabismus}}
Strabismus, sometimes also incorrectly called lazy eye, is a condition in which the eyes are misaligned.<ref name=handbook>{{cite book|title=Handbook of Pediatric Strabismus and Amblyopia | last1 = Wright | first1 = Kenneth W. | last2 = Spiegel | first2 = Peter H. | last3 = Thompson | first3 = Lisa S. | name-list-style = vanc |year=2006|isbn=978-0-387-27924-4|publisher=[[Springer Science+Business Media|Springer]]|location=New York, New York}}</ref> Strabismus usually results in normal vision in the preferred sighting (or "fellow") eye (the eye that the person prefers to use), but may cause abnormal vision in the deviating or strabismic eye due to the difference between the images projecting to the brain from the two eyes.<ref>{{cite journal | vauthors = Levi DM | title = Visual processing in amblyopia: human studies | journal = Strabismus | volume = 14 | issue = 1 | pages = 11–9 | date = March 2006 | pmid = 16513566 | doi = 10.1080/09273970500536243 | s2cid = 29190763 }}</ref>
Adult-onset strabismus usually causes double vision ([[diplopia]]), since the two eyes are not fixed on the same object.
Children's brains are more [[Neuroplasticity|neuroplastic]], so can more easily adapt by [[Suppression (eye)|suppressing images]] from one of the eyes, eliminating the double vision. This plastic response of the brain interrupts the brain's normal development, resulting in the amblyopia.{{citation needed|date=July 2018}} Recent evidence points to a cause of infantile strabismus lying with the input to the [[visual cortex]].<ref>{{cite journal | vauthors = Tychsen L | title = The cause of infantile strabismus lies upstairs in the cerebral cortex, not downstairs in the brainstem | journal = Archives of Ophthalmology | volume = 130 | issue = 8 | pages = 1060–1 | date = August 2012 | pmid = 22893080 | doi = 10.1001/archophthalmol.2012.1481 }}</ref>

Those with strabismic amblyopia tend to show ocular motion deficits when reading, even when they use the nonamblyopic eye. In particular, they tend to make more [[saccade]]s per line than persons with normal stereo vision, and to have a reduced [[reading speed]], especially when reading a text with small [[font size]].<ref name="pmid24370829">{{cite journal | vauthors = Kanonidou E, Gottlob I, Proudlock FA | title = The effect of font size on reading performance in strabismic amblyopia: an eye movement investigation | journal = Investigative Ophthalmology & Visual Science | volume = 55 | issue = 1 | pages = 451–9 | date = January 2014 | pmid = 24370829 | doi = 10.1167/iovs.13-13257 | doi-access = free | hdl = 2381/38991 | hdl-access = free }}</ref><ref name="pmid20207968">{{cite journal | vauthors = Kanonidou E, Proudlock FA, Gottlob I | title = Reading strategies in mild to moderate strabismic amblyopia: an eye movement investigation | journal = Investigative Ophthalmology & Visual Science | volume = 51 | issue = 7 | pages = 3502–8 | date = July 2010 | pmid = 20207968 | doi = 10.1167/iovs.09-4236 | doi-access =  }}</ref>{{primary source inline|date=February 2019}}

Strabismic amblyopia is treated by clarifying the visual image with glasses, or encouraging use of the amblyopic eye with an [[eyepatch]] over the dominant eye or [[Atropine#Ophthalmic use|pharmacologic penalization]] of the better eye. Penalization usually consists of applying [[atropine]] drops to temporarily paralyze the accommodation reflex, leading to the blurring of vision in the good eye. It also dilates the [[pupil]]. This helps to prevent the bullying and teasing associated with wearing a patch, although sometimes application of the eye drops is challenging. The ocular alignment itself may be treated with surgical or nonsurgical methods, depending on the type and severity of the strabismus.<ref name="Holmes">{{cite journal | vauthors = Holmes JM, Repka MX, Kraker RT, Clarke MP | title = The treatment of amblyopia | journal = Strabismus | volume = 14 | issue = 1 | pages = 37–42 | date = March 2006 | pmid = 16513568 | doi = 10.1080/09273970500536227 | s2cid = 31165871 }}</ref>