View source for Unsolved:Photopsia

{{short description|Presence of perceived flashes of light in one's field of vision}}
{{Infobox medical condition|name=Photopsia|image=Migraine aura.jpg|alt=|caption=This is an approximation of the zig-zag visual of a [[Unsolved:Scintillating scotoma|scintillating scotoma]] as a migraine aura. It moves and vibrates, expanding and slowly fading away over the course of about 20 minutes.|synonym=|image_size=|pronounce=|specialty=Ophthalmology, Neurology|symptoms=Flickering lights or flashes in the field of vision, along with pain, loss of colour perception, and eventual vision loss are also part of the damage to the optic nerve during optic neuritis<ref>{{cite web |title=Photopsia: Is It Dangerous? (How to Treat It) - Nvision |url=https://www.nvisioncenters.com/conditions/photopsia/ |website=Nvision |access-date=30 August 2019}}</ref>|onset=During [[Medicine:Pregnancy|pregnancy]]|duration=Migraine with aura, which includes photopsia 39% of the time, typically lasts 10 to 20 minutes and often is followed by a headache.<ref>{{cite web |title=The woman who saw the light |url=https://www.mdedge.com/psychiatry/article/66344/schizophrenia-other-psychotic-disorders/woman-who-saw-light/page/0/1 |website=MDedge Psychiatry |access-date=31 August 2019}}</ref>|types=|causes=Peripheral (Posterior) vitreous detachment, retinal detachment, age-related macular degeneration, ocular (retinal) migraine / migraine aura, vertebrobasilar insufficiency, optic neuritis, occipital lobe infarction (similar to occipital stroke), sensory deprivation (ophthalmopathic hallucinations)|risks=Above age 50 (risk of retinal detachment)<ref>{{cite web |title=Retinal detachment - Symptoms and causes - Mayo Clinic |url=https://www.mayoclinic.org/diseases-conditions/retinal-detachment/symptoms-causes/syc-20351344 |website=Mayo Clinic |access-date=30 August 2019}}</ref>|diagnosis=|differential=|prevention=|treatment=In most cases, photopsia is a symptom of a preexisting condition. The underlying condition must be identified and treated to resolve the symptoms.|medication=|prognosis=|frequency=|deaths=}}'''Photopsia''' is the presence of perceived flashes of light in the [[Biology:Visual field|field of vision]]. 

It is most commonly associated with:<ref name="EyeRounds">{{cite web|first1=Nicole C.|last1=Morrow|first2=Anthony T.|last2=Chung|first3=Michael|last3=Wall|title=Photopsias|url=https://eyerounds.org/tutorials/photopsias/index.htm|access-date=20 June 2020|website=EyeRounds.org|publisher=University of Iowa Carver College of Medicine}}</ref>

* [[Medicine:Posterior vitreous detachment|posterior vitreous detachment]]
* migraine aura (ocular migraine / [[Medicine:Retinal migraine|retinal migraine]])
* migraine aura without headache
* [[Unsolved:Scintillating scotoma|scintillating scotoma]]
* [[Medicine:Retinal detachment|retinal break or detachment]]
* [[Biology:Occipital lobe|occipital lobe]] infarction (similar to [[Medicine:Stroke|occipital stroke]])
* [[Philosophy:Sensory deprivation|sensory deprivation]] (ophthalmopathic hallucinations)
* [[Medicine:Macular degeneration|age-related macular degeneration]]
* [[Medicine:Vertebrobasilar insufficiency|vertebrobasilar insufficiency]] 
* [[Medicine:Optic neuritis|optic neuritis]]
* [[Unsolved:Visual snow syndrome|visual snow syndrome]]

Vitreous shrinkage or [[Physics:Liquefaction|liquefaction]], which are the most common causes of photopsia, cause a pull in vitreoretinal attachments, irritating the [[Biology:Retina|retina]] and causing it to discharge electrical impulses. These impulses are interpreted by the [[Biology:Brain|brain]] as flashes.

This condition has also been identified as a common initial symptom of [[Medicine:Punctate inner choroiditis|punctate inner choroiditis]] ([[Medicine:Punctate inner choroiditis|PIC]]),<ref>{{Cite web|url=https://rarediseases.info.nih.gov/diseases/7503/punctate-inner-choroidopathy|title=Punctate inner choroidopathy {{!}} Genetic and Rare Diseases Information Center (GARD) – an NCATS Program|website=rarediseases.info.nih.gov|access-date=2019-08-28}}</ref> a rare retinal [[Medicine:Autoimmunity|autoimmune]] disease believed to be caused by the [[Biology:Immune system|immune system]] mistakenly attacking and destroying the [[Biology:Retina|retina]].  During [[Medicine:Pregnancy|pregnancy]], new-onset photopsia is concerning for severe preeclampsia.

Photopsia can present as [[Medicine:Retinal detachment|retinal detachment]] when examined by an [[Medicine:Optometry|optometrist]] or [[Medicine:Ophthalmology|ophthalmologist]]. However, it can also be a sign of [[Medicine:Uveal melanoma|uveal melanoma]].  This condition is extremely rare (5–7 per 1 million people will be affected, typically fair-skinned, blue-eyed northern Europeans). Photopsia should be investigated immediately.

== Causes ==
Several conditions affecting the eyes can cause photopsia to occur. The underlying condition must be identified and treated to resolve the symptoms.

=== Peripheral (posterior) vitreous detachment ===
[[Medicine:Posterior vitreous detachment|Peripheral (posterior) vitreous detachment]] occurs when the gel around the [[Biology:Eye|eye]] separates from the [[Biology:Retina|retina]]. This can naturally occur with age. However, if it occurs too rapidly, it can cause photopsia which manifests in flashes and floaters in the [[Biology:Visual field|vision]]. Typically, the flashes and floaters go away in a few months.

=== Retinal detachment ===
The retina lines the inside of the [[Biology:Eye|eye]]. It is light-sensitive and communicates visual messages to the brain. If the retina detaches, it moves and shifts from its normal position. This can cause photopsia, but can also cause permanent [[Medicine:Visual impairment|vision loss]]. Medical attention is needed to prevent vision loss. Procedures may include laser treatment, freezing, or [[Medicine:Surgery|surgery]].

=== Age-related macular degeneration ===
Age-related [[Medicine:Macular degeneration|macular degeneration]] (AMD) is a common eye condition among people aged 50 and older. The [[Medicine:Macula of retina|macula]] is a part of the eye that helps you see sharply straight ahead. With AMD, the macula slowly deteriorates which can cause photopsia.

=== Ocular (retinal) migraine / Migraine aura ===
Migraines are a type of recurring headache. Migraines typically cause severe pain in the head, but can also cause visual changes known as [[Unsolved:Aura (symptom)|auras]]. Migraines can also cause [[Unsolved:Visual snow|visual snow]].

=== Optic neuritis ===
[[Medicine:Optic neuritis|Optic neuritis]] is an [[Medicine:Inflammation|inflammation]] that damages the [[Biology:Optic nerve|optic nerve]]. It’s linked to multiple sclerosis (MS). Along with flickering or flashing with [[Biology:Eye movement|eye movement]], symptoms include pain, loss of [[Color vision|colour perception]], and [[Medicine:Visual impairment|vision loss]].

=== Occipital lobe infarction (stroke) or ischemia ===
The [[Biology:Occipital lobe|occipital lobe]] is one of four lobes in the [[Biology:Brain|brain]]. It controls the ability to see things. Impaired blood flow to the cells of the occipital lobe ([[Medicine:Ischemia|ischemia]], for example as caused by a [[Medicine:Transient ischemic attack|TIA]] or [[Medicine:Vertebrobasilar insufficiency|Vertebrobasilar insufficiency]]) will lead to temporary visual problems; if the poor blood flow is sustained it will lead to [[Biology:Cell death|cell death]] (infarction, for example as caused by a [[Medicine:Stroke|stroke]]) which may cause persistent visual problems.

The main symptoms associated with an occipital lobe infarction involve changes to vision such as:

* blurry vision
* [[Medicine:Blindness|blindness]], which may affect part of vision only
* [[Unsolved:Hallucination|hallucinations]], such as flashing lights (photopsia): usually only in the context of [[Medicine:Visual impairment|blindness]]

=== Sensory deprivation (Ophthalmopathic hallucinations) ===
[[Philosophy:Sensory deprivation|Sensory deprivation]] or ophthalmopathic hallucination are [[Unsolved:Hallucination|hallucination]]s that appear in the [[Biology:Visual field|field of vision]].

== Appearance ==
Photopsias is defined as an effect on the vision that causes appearances of anomalies in the [[Biology:Visual field|vision]]. Photopsias usually appear as:

* flickering lights
* shimmering lights
* floating shapes
* moving dots
*[[Unsolved:Visual snow|snow or static]]

Photopsias are not generally a condition on their own, but a [[Medicine:Symptom|symptom]] of another condition.

==See also==
{{div col}}
* {{annotated link|Medicine:Moore's lightning streaks}}
* {{annotated link|Biology:Phosphene}}
* {{annotated link|Philosophy:Sensory deprivation}}
* {{annotated link|Medicine:Vertebrobasilar insufficiency}}
{{div col end}}

==References==
<references />

*{{cite journal | author=Amos JF | title=Differential diagnosis of common etiologies of photopsia | journal=J Am Optom Assoc | year=1999 | pages=485–504 | volume=70 | issue=8  | pmid=10506812}}
* Engmann, Birk (2008). "Phosphenes and photopsias – ischaemic origin or sensorial deprivation? – Case history." ''Z. Neuropsychol''. '''19'''(1): 7–13.  {{ISSN|1016-264X}} {{doi|10.1024/1016-264X.19.1.7}}
* Chu, David S. (MD) (2001). Ocular Immunology and Uveitis Foundation.  https://web.archive.org/web/20160304061225/http://www.uveitis.org/docs/dm/punctate_inner_choroiditis.pdf
* Sihota, Ramanjit. Tandon, Radhika.(2011). Parsons' Disease of the Eye.  2011. Edition 21st. pp. 90–91. {{ISBN|978-81-312-2554-7}}

[[Category:Eye diseases]]
[[Category:Medical signs]]
[[Category:Hallucinations]]

{{Sourceattribution|Photopsia}}