Migrena siatkówkowa – Patofizjologia i mechanizm

Migrena siatkówkowa
Patofizjologia i mechanizm

Migrena siatkówkowa to rzadki typ migreny objawiający się przemijającymi, jednostronnymi zaburzeniami widzenia trwającymi od 5 do 60 minut, po których następuje ból głowy o charakterze migrenowym. Patofizjologia pozostaje nie do końca poznana, jednak dominują dwie teorie: skurcz naczyń krwionośnych zaopatrujących siatkówkę (wazospazm tętnicy środkowej siatkówki lub tętnicy ocznej) prowadzący do przejściowego niedokrwienia, oraz rozprzestrzeniająca się depresja neuronów siatkówki, analogiczna do korowej depresji rozprzestrzeniającej się (CSD). W patomechanizmie istotną rolę odgrywają neuropeptydy, takie jak CGRP, substancja P i tlenek azotu, które wywołują zapalenie neurogenne i rozszerzenie naczyń. Badania OCTA wykazały zmniejszenie gęstości naczyń siatkówki i zmiany w nerwie wzrokowym u pacjentów z migreną, co może prowadzić do ścieńczenia warstwy włókien nerwowych siatkówki (RNFL) i potencjalnej utraty aksonów komórek zwojowych.

Patogeneza migreny siatkówkowej

Migrena siatkówkowa (retinal migraine) to rzadki typ migreny charakteryzujący się przemijającymi zaburzeniami widzenia w jednym oku, po których w ciągu 60 minut następuje ból głowy o charakterze migrenowym. Mimo prowadzonych badań, dokładna patofizjologia tej choroby pozostaje w dużej mierze niewyjaśniona i kontrowersyjna, a naukowcy proponują kilka teorii wyjaśniających jej mechanizm.¹²³

Teoria naczyniowa (skurczu naczyń)

Jedna z najczęściej przywoływanych teorii sugeruje, że migrena siatkówkowa jest wynikiem skurczu (wazospazmu) naczyń krwionośnych zaopatrujących siatkówkę lub naczyniówkę. Zgodnie z tą teorią, nagłe zwężenie tętnic doprowadzających krew do oka powoduje przejściowe niedokrwienie siatkówki, co prowadzi do zaburzeń widzenia.¹²³

Po ustąpieniu skurczu naczyń, przepływ krwi powraca do normy, a objawy ustępują. Teoria ta została po raz pierwszy zaproponowana przez Carrolla w latach 70. XX wieku, który sugerował, że mechanizm utraty widzenia jest spowodowany napadowym skurczem tętnicy środkowej siatkówki lub tętnicy ocznej.¹²

Podczas badania w trakcie napadu migreny siatkówkowej, można zaobserwować opóźnione wypełnianie lub niedrożność tętnicy środkowej siatkówki i jej gałęzi, przy normalnym krążeniu rzęskowym lub plamistych ubytkach naczyniówkowych i zaniku naczyń włosowatych, co potwierdzają badania angiograficzne.¹²

Należy jednak zaznaczyć, że teoria naczyniowa pozostaje kontrowersyjna ze względu na złożoność układu unaczynienia siatkówki. Siatkówka posiada podwójne unaczynienie – tętnica środkowa siatkówki zaopatruje wewnętrzne warstwy siatkówki, nie posiada unerwienia adrenergicznego, zachowuje nerwy czuciowe i jest autoregulowana. Z kolei krążenie naczyniówkowe zaopatruje tylną część siatkówki, w tym fotoreceptory, posiada włókna adrenergiczne bez autoregulacji.¹²

Teoria rozprzestrzeniającej się depresji korowej

Alternatywna teoria sugeruje, że migrena siatkówkowa jest spowodowana rozprzestrzeniającą się depresją neuronów siatkówki (ang. retinal spreading depression), podobną do rozprzestrzeniającej się depresji korowej (ang. cortical spreading depression, CSD), która jest akceptowaną koncepcją typowej aury migrenowej.¹²³

CSD charakteryzuje się falą depolaryzacji neuronów i komórek glejowych, która rozprzestrzenia się przez korę mózgową z prędkością 2-3 mm na minutę. Fala nadpobudliwości wywołuje pozytywne objawy wzrokowe (scyntylacje, fotopsje), a następująca po niej fala obniżonej aktywności elektrycznej odpowiada za towarzyszące mroczki.¹²

Podobny mechanizm może występować w siatkówce, gdzie rozprzestrzeniająca się depolaryzacja prowadzi do zaburzenia gradientów jonowych i utraty oporności błonowej. Zwiększone stężenie potasu sprzyja rozprzestrzenianiu się depolaryzacji przez tkankę nerwową i prowadzi do uwalniania pobudzających aminokwasów, które potęgują to rozprzestrzenianie.¹

Należy zaznaczyć, że zjawisko rozprzestrzeniającej się depresji siatkówki zostało wykazane w warunkach laboratoryjnych u różnych zwierząt, w tym u kurczaków i gryzoni, ale nigdy oficjalnie nie zostało potwierdzone u ludzi.¹

Rola neuropeptydów i mediatorów zapalnych

W patofizjologii migreny siatkówkowej istotną rolę mogą odgrywać różne neuropeptydy i mediatory zapalne. Substancja P, tlenek azotu i peptydy związane z genem kalcytoniny (CGRP) zostały wskazane jako potencjalne efektory chemiczne w mechanizmach patofizjologicznych, wywierając niepożądany wpływ prowadzący do wynaczynienia osocza, zapalenia neurogennego i rozszerzenia naczyń.¹²

Badania przedkliniczne sugerują, że CGRP i jego receptor są wyrażane w wielu regionach anatomicznych istotnych dla migreny (np. układzie trójdzielno-naczyniowym i czaszkowym układzie przywspółczulnym). Dowody kliniczne sugerują, że CGRP uczestniczy w bólu migrenowym.¹

Neuropeptydy mogą odgrywać fundamentalną rolę w zapaleniu neurogennym oraz obwodowej i centralnej sensytyzacji układu trójdzielno-naczyniowego i innych systemów. Prowadzi to do stanu nadwrażliwości układu nerwowego i utrzymującego się bólu.¹²

Zmiany strukturalne w siatkówce

Badania wykazały, że migrena może prowadzić do zmian strukturalnych w siatkówce. Niektórzy badacze uważają, że depresja aktywności elektrycznej w neuronie może powodować ścieńczenie warstwy włókien nerwowych siatkówki (RNFL).¹

RNFL składa się z aksonów komórek zwojowych siatkówki. Ścieńczenie tej warstwy odzwierciedla utratę aksonów i objawy upośledzenia widzenia. Z czasem, ten wzorzec występowania może stopniowo negatywnie zmieniać strukturę zarówno mózgu, jak i siatkówki, co prowadzi do nieprawidłowej zmiany w strukturze i formacji komórek zwojowych w siatkówce, potencjalnie prowadząc do ich ostatecznej śmierci.¹

Badania wykazały również znaczące zmniejszenie gęstości naczyń siatkówki w plamce i zmiany w nerwie wzrokowym u pacjentów z migreną. Przejściowe i nawracające zmniejszenie dopływu krwi do tarczy nerwu wzrokowego może prowadzić do niedokrwiennej śmierci komórek zwojowych.¹²

Badania z wykorzystaniem optycznej koherentnej tomografii angiografii (OCTA) ujawniły kilka zmian w naczyniach siatkówki podczas napadu migreny i między napadami, w tym zmiany w kształcie i ukrwieniu siatkówki.¹

Mechanizm powstawania objawów

Migrena siatkówkowa charakteryzuje się specyficznymi objawami, które wynikają z jej patofizjologii. Zrozumienie mechanizmu powstawania tych objawów jest kluczowe dla właściwej diagnozy i leczenia.

Przejściowa utrata widzenia w jednym oku

Główną cechą migreny siatkówkowej jest przejściowa utrata widzenia lub zaburzenia widzenia w jednym oku. W przeciwieństwie do migreny z aurą, gdzie objawy wzrokowe występują w obu oczach, w migrenie siatkówkowej zaburzenia dotyczą tylko jednego oka.¹²

Mechanizm powstawania jednostronnych zaburzeń widzenia można wytłumaczyć niedokrwieniem siatkówki spowodowanym skurczem naczyń krwionośnych zaopatrujących oko. Zmniejszony przepływ krwi do siatkówki prowadzi do niedotlenienia fotoreceptorów i innych komórek siatkówki, co objawia się jako mroczki, ubytki w polu widzenia lub całkowita ślepota oka.¹²

Objawy wzrokowe mogą obejmować: błyski światła, migotanie, scyntylacje, mroczki (skotomaty), zaciemnienie pola widzenia lub przejściową ślepotę. Zwykle rozwijają się stopniowo w ciągu 5 minut lub dłużej i trwają od 5 do 60 minut.¹²

Ból głowy po zaburzeniach wzrokowych

Po ustąpieniu objawów wzrokowych lub w ich trakcie, w ciągu 60 minut, pojawia się typowy ból głowy o charakterze migrenowym. Zgodnie z definicją Międzynarodowej Klasyfikacji Bólu Głowy (ICHD-3), migrena siatkówkowa to „powtarzające się napady jednostronnych zaburzeń widzenia, w tym scyntylacje, mroczki lub ślepota, związane z bólem głowy o charakterze migrenowym”.¹²

Ból głowy jest zwykle pulsujący, tętniący lub pukający i zazwyczaj zlokalizowany za dotkniętym okiem. Może mu towarzyszyć nudności, wymioty, nadwrażliwość na światło (fotofobia) i nadmierna nietolerancja dźwięku (fonofobia).¹²

Mechanizm bólu głowy w migrenie siatkówkowej prawdopodobnie związany jest ze skurczem lub podrażnieniem naczyń krwionośnych w mózgu, które są wrażliwe na ból (w przeciwieństwie do samej tkanki mózgowej, która nie posiada receptorów bólu).¹

Aktywacja układu trójdzielno-naczyniowego

Ważnym elementem w patofizjologii migreny siatkówkowej jest aktywacja układu trójdzielno-naczyniowego, który odgrywa kluczową rolę w patogenezie migreny. System ten pośredniczy w rozszerzeniu naczyń oponowych i zewnątrznaczyniowym wynaczynieniu białek osocza oraz mediatorów zapalnych, co z kolei prowadzi do jałowego zapalenia i skurczu naczyń, powodując typowy pulsujący ból głowy.¹

Aktywacja pierwotnych nocyceptorów i centralnych neuronów trójdzielno-naczyniowych może przyczyniać się do allodynii w migrenie. Badania z wykorzystaniem obrazowania metodą rezonansu magnetycznego (MRI) wykazały, że pacjenci z migreną i większymi objawami allodynii mogą wykazywać nieprawidłowości strukturalne w obrębie pnia mózgu.¹

Wejście nocyceptywne z siatkówki i nerwu trójdzielnego zbiega się we wzgórzu, które projektuje do obszarów nocyceptywnych kory (S1/S2), co może prowadzić do nasilenia bólu głowy migrenowego przez światło. Nadwrażliwa kora wzrokowa (V1/V2) może również przyczyniać się do tego efektu.¹

Czynniki ryzyka i wyzwalacze

Migrena siatkówkowa może być wywoływana przez podobne czynniki jak inne typy migreny, a zrozumienie tych wyzwalaczy jest kluczowe dla profilaktyki i zarządzania tą chorobą.

Czynniki wyzwalające

Ataki migreny siatkówkowej są wywoływane przez podobne czynniki jak migrena z aurą. Do najczęstszych wyzwalaczy należą:¹²³

Stres emocjonalny
Nadciśnienie tętnicze
Palenie tytoniu
Hormonalne środki antykoncepcyjne
Wysiłek fizyczny
Przebywanie na dużej wysokości
Odwodnienie
Hipoglikemia (niski poziom cukru we krwi)
Nadmierne ciepło
Kofeina i alkohol
Pochylanie się

¹²

Czynniki genetyczne

Silny wywiad rodzinny u pacjentów z migreną siatkówkową sugeruje, że choroba ta ma predyspozycje genetyczne, choć nie opisano wyraźnego wzorca dziedziczenia. Badania wykazały, że 50% osób doświadczających migreny siatkówkowej ma rodzinną historię bólów głowy migrenowych.¹²

Choroby współistniejące

Współistnienie z pewnymi chorobami zwiększa ryzyko wystąpienia migreny siatkówkowej. Należą do nich:¹

Toczeń rumieniowaty (lupus)
Miażdżyca tętnic
Anemia sierpowata

Ponadto, u osób z migreną siatkówkową zidentyfikowano niewielkie czynniki ryzyka chorób naczyniowych, takie jak:¹

Nadciśnienie tętnicze
Nadczynność tarczycy
Ciąża
Cukrzyca
Stosowanie doustnych środków antykoncepcyjnych
Palenie tytoniu
Podwyższony poziom czynnika VIII

Dysregulacja naczyniowa

Podstawowa dysregulacja naczyniowa jest związana z chorobą naczyń siatkówki i współwystępuje z migreną. Teoretycznie może być czynnikiem w patogenezie migreny siatkówkowej.¹

Pacjenci z migreną mają zwiększone ryzyko przetrwałego otworu owalnego (PFO) i rozwarstwienia tętnicy szyjnej, które mogą przyczyniać się do niedokrwienia tętnicy siatkówki.¹

Potencjalne powikłania

Chociaż migrena siatkówkowa jest zazwyczaj łagodnym schorzeniem, które nie powoduje trwałych uszkodzeń, w rzadkich przypadkach mogą wystąpić powikłania związane z niedokrwieniem siatkówki.

Trwała utrata widzenia

Nieodwracalna utrata wzroku jest możliwym powikłaniem migreny siatkówkowej, ale jest rzadka. Istnieje nadal niepewność co do tego, jak często migrena siatkówkowa może powodować trwałą utratę wzroku, a obecnie nie ma badań, które mogłyby przewidzieć, kto zostanie dotknięty i w jaki sposób.¹²

Istnieje niewielkie ryzyko, że zmniejszony przepływ krwi może uszkodzić cienką warstwę z tyłu oka (siatkówkę) i naczynia krwionośne oka.¹²

Powikłania naczyniowe

Powikłania migreny siatkówkowej mogą obejmować:¹

Niedrożność tętnicy środkowej siatkówki (CRAO)
Zawał siatkówki
Niedrożność żyły środkowej siatkówki
Niedrożność gałęzi tętnicy siatkówki (BRAO)
Krwotoki siatkówkowe, które mogą prowadzić do obrzęku siatkówki i tarczy nerwu wzrokowego
Niedokrwienie naczyniówki lub nerwu wzrokowego
Krwotok do ciała szklistego

Dane dotyczące pola widzenia sugerują, że w migrenie siatkówkowej występuje wyższa częstość zawałów w obszarze dystrybucji końcowej tętniczek i wyższa częstość trwałych ubytków w polu widzenia niż w klinicznie jawnych zawałach mózgu w migrenie z aurą.¹²

Zwiększone ryzyko chorób naczyniowych

Ze względu na powiązanie z innymi układami ciała, pacjenci doświadczający tych migren, szczególnie z aurą, mają zwiększone ryzyko choroby serca, udaru niedokrwiennego, a nawet śmiertelności.¹

Badania wykazały, że migrena jest związana z wyższym ryzykiem niedrożności naczyń siatkówki, w tym niedrożności tętnicy siatkówki (RAO) i niedrożności żyły siatkówki (RVO), a także ich podtypów.¹

Choć mechanizmy wpływu migreny na niedrożność naczyń siatkówki są prawdopodobnie wieloczynnikowe i obecnie trudne do jednoznacznego określenia, zaproponowano kilka hipotez:¹²

Zmiany w funkcji śródbłonka i tętnic, które predysponują do miażdżycy i chorób sercowo-naczyniowych
Migotanie przedsionków, które jest główną przyczyną zatorów sercowych
Mutacje genu reduktazy metylenotetrahydrofolianowej (MTHFR), w tym MTHFR C677T i A1298C, które wpływają na poziom homocysteiny
Hiperkoagulacja i inne zaburzenia krzepnięcia

Znaczenie kliniczne i diagnostyka

Migrena siatkówkowa jest niezwykle rzadką przyczyną przejściowej jednookularnej utraty wzroku. Właściwa diagnostyka różnicowa jest kluczowa, aby wykluczyć inne, potencjalnie poważniejsze przyczyny przejściowej ślepoty jednookularnej.¹²

Diagnostyka różnicowa

Istnieje istotne nakładanie się objawów migreny siatkówkowej i amaurosis fugax, który jest szerokim terminem opisującym naczyniowe przyczyny przejściowej utraty wzroku w jednym oku (np. zapalenie tętnicy skroniowej, skurcz naczyń siatkówki lub zator siatkówki).¹

Ponieważ migrena siatkówkowa jest bardzo rzadką przyczyną przejściowego zaburzenia widzenia jednookularnego, u pacjentów bez wcześniejszej historii tego schorzenia należy przeprowadzić dalsze badania, aby wykluczyć alternatywne przyczyny, takie jak amaurosis fugax.¹²

Konieczne jest również różnicowanie z chorobami oka lub przyczynami naczyniowymi przejściowej ślepoty jednookularnej, głównie chorobą tętnicy szyjnej i zaburzeniami krzepnięcia.¹²

Diagnostyka kliniczna

Nie istnieją specyficzne testy diagnostyczne potwierdzające migrenę siatkówkową. Diagnoza opiera się na wykluczeniu innych możliwych pierwotnych zaburzeń bólu głowy i przyczyn zaburzeń widzenia, w tym chorób oczu.¹²

Diagnoza migreny siatkówkowej jest stawiana na podstawie wywiadu powtarzających się ataków przejściowych zaburzeń widzenia lub ślepoty jednookularnej, z lub bez bólu głowy i bez innych objawów neurologicznych. Osobista lub rodzinna historia migreny potwierdza diagnozę.¹

Według Międzynarodowej Klasyfikacji Bólu Głowy (ICHD-3), aby postawić diagnozę migreny siatkówkowej, ataki muszą spełniać kryteria migreny z aurą, a objawy wzrokowe powinny narastać stopniowo, trwać 60 minut lub krócej i być związane z bólem głowy w momencie wystąpienia lub w ciągu 1 godziny.¹²

Zalecenia dotyczące badań

Należy natychmiast skonsultować się z pracownikiem służby zdrowia w przypadku następujących objawów:¹

Zmiany wzrokowe tylko w jednym oku
Zmiany wzrokowe, które trwają krócej niż 5 minut lub dłużej niż 60 minut
Zmiany wzrokowe bez bólu głowy
Nowe bóle głowy lub nowe zmiany wzrokowe
Bóle głowy lub zmiany wzrokowe, które rozpoczynają się po 50. roku życia
Nowe osłabienie jednej strony ciała lub zmiany mowy

Te objawy mogą sugerować poważniejszą przyczynę objawów wzrokowych i wymagają uwagi medycznej.¹²

Implikacje terapeutyczne

Zrozumienie patofizjologii migreny siatkówkowej ma istotne implikacje dla jej leczenia. Ze względu na mechanizm skurczu naczyń, niektóre leki stosowane w innych typach migreny mogą być przeciwwskazane w migrenie siatkówkowej.

Ograniczenia w stosowaniu leków

Ważne jest, aby unikać stosowania tryptanów, ergotów i beta-blokerów w migrenie z przejściową utratą wzroku ze względu na ryzyko nasilenia skurczu naczyń i zwiększenia ryzyka nieodwracalnej utraty wzroku.¹²

Niektóre leki stosowane w innych typach migreny, jak tryptany, mogą przedłużać utratę wzroku według American Migraine Foundation.¹²³

Zalecane leczenie profilaktyczne

Nie ma jasnych wytycznych dotyczących postępowania z pacjentami z migreną siatkówkową. Gdy zaburzenia wzrokowe się rozpoczną, muszą one przebiec swój naturalny cykl.¹

Terapie zapobiegawcze stosowane w innych typach migreny mogą być skuteczne. Mogą to obejmować leki z następujących rodzin:¹

Blokery kanału wapniowego (obniżające ciśnienie krwi)
Leki przeciwdrgawkowe
Leki przeciwdepresyjne

Codzienna niska dawka aspiryny również może być pomocna.¹

Zalecane leki zapobiegawcze dla migreny ocznej to leki obniżające ciśnienie krwi, takie jak blokery kanału wapniowego lub beta-blokery. Oba te leki zmniejszają skurcz naczyń krwionośnych.¹

Potencjalne nowe terapie

Peptyd związany z genem kalcytoniny (CGRP) występuje w siatkówce, ale nie wiadomo, czy leki celujące w CGRP są przydatne w tym typie migreny.¹

Możliwe implikacje odkryć dotyczących zwężania się naczyń krwionośnych sugerują, że leki rozrzedzające krew lub neutralizujące skrzepy za pomocą inwazyjnych strategii mogą być źródłem przyszłych badań.¹

Potrzeba więcej badań w tym wyraźnym klinicznym schorzeniu, ponieważ termin „migrena siatkówkowa” może być błędnym określeniem, które myli klinicystów i pacjentów.¹

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Materiały źródłowe

#1 Retinal Migraine Headache – StatPearls – NCBI Bookshelf
https://www.ncbi.nlm.nih.gov/books/NBK507725/
Ocular or retinal migraines are generally defined as a transient monocular scotoma or loss of vision that is accompanied or followed by a headache within 60 minutes of visual symptoms onset. […] The pathophysiology of those persistent deficits is not clear. […] The pathophysiology of migraine remains controversial. One theory of ocular migraine is that it is due to vasospasm within the retinal or ciliary vasculature while others think it is a spreading depression of the neuron in the retina that is similar to the spreading depression of the cerebral cortex. […] The vasospasm theory is controversial due to the complexity of the retinal vascular supply. […] Retinal migraine attacks are precipitated by similar factors as a migraine with aurae such as stress, smoking, hypertension, hormonal contraceptive pills, exercise, bending over, high altitude, dehydration, hypoglycemia, or excessive heat. […] The fluorescein angiogram shows delayed filling or occlusion of the central retinal artery and its branches with either a normal ciliary circulation or patchy choroidal defects and capillary dropout.
#1 Retinal migraine
https://www.nhs.uk/conditions/retinal-migraine/
Retinal migraines are thought to happen when the blood vessels in your eye suddenly narrow, restricting the blood flow. […] Things that can cause them include: stress, caffeine and alcohol, dehydration, smoking, high blood pressure, bending over, low blood sugar, some types of hormonal contraception.
#1 Current Perspective on Retinal Migraine
https://www.mdpi.com/2411-5150/5/3/38
Retinal migraine was first formally described in 1882. […] The latest ICHD defined retinal migraine as ârepeated attacks of monocular visual disturbance, including scintillation, scotoma or blindness, associated with migraine headacheâ, which are fully reversible. […] The aim of this narrative review is to summarize the literature on retinal migraine, including: epidemiology and risk factors; proposed aetiology; clinical presentation; and management strategies. It is potentially a misnomer as its proposed aetiology is different from our current understanding of the mechanism of migraine. […] When Carroll described the term retinal migraine in the 1970s, he hypothesized that the mechanism of visual loss is due to paroxysmal constriction or spasm in either the central retinal artery or ophthalmic artery.
#1 Retinal Migraine Headache | Treatment & Management | Point of Care
https://www.statpearls.com/point-of-care/28450
Retinal migraine attacks are precipitated by similar factors as a migraine with aurae such as stress, smoking, hypertension, hormonal contraceptive pills, exercise, bending over, high altitude, dehydration, hypoglycemia, or excessive heat. Strong family history in these patients suggests that a retinal migraine has a genetic predisposition but no clear pattern of inheritance has been described. The vasospasm theory is controversial due to the complexity of the retinal vascular supply. Retina has dual circulation, central retinal artery supplies, inner retinal layers, lacks adrenergic innervation, maintains sensory nerves, and is auto-regulated. The choroidal circulation supplies the posterior retina including the photoreceptors it carries adrenergic fibers without autoregulation. […] […] Complications of a retinal migraine include central retinal artery occlusion (CRAO), retinal infarction, central retinal venous occlusion, branch retinal artery occlusion (BRAO), retinal hemorrhages that can lead to edema of the retina and disc, ischemia of choroid or optic nerve, and vitreous hemorrhage. Many of those could lead to irreversible vision loss in the patient. It is important to avoid the use of triptans, ergots, and beta-blockers in migraines with transient vision loss secondary to the risk of potentiating vasoconstriction and increasing the risk of irreversible visual loss.
#1 Retinal migraine | MedLink Neurology
https://www.medlink.com/articles/retinal-migraine
Retinal migraine is usually characterized by attacks of fully reversible monocular visual loss associated with migraine headache. […] The underlying pathophysiology of retinal migraine remains largely unknown. Bouts of transient monocular visual loss lasting less than 1 hour, transient monocular visual loss of prolonged duration, and transient monocular visual loss that later becomes permanent correspond clinically to the conventional auras of migraine, prolonged auras, and migrainous infarction, respectively. […] Spreading depression of cortical neurons is the accepted concept of the typical aura of migraine and perhaps a similar mechanism affects the retina. […] Primary vascular dysregulation is associated with retinal vascular disease and is comorbid with migraine. Theoretically, it could be a factor in the pathogenesis of retinal migraine.
#1 Lesson: What to Do When the Patient Says They Have âOcular Migraineâ
https://www.revieweducationgroup.com/ce/what-to-do-when-the-patient-says-they-have-ocular-migraine
Cortical spreading depression (CSD). Aura of migraine (specifically visual aura) is a cortical process resulting in binocular symptoms. CSD is recognized as a key neuropathogenic mechanism in the visual aura of migraine. It originates in the visual cortex as a slow-moving wave of depolarization of neurons and glial cells, which then propagates throughout the cortex at a rate of 2mm to 3mm per minute. The wave of hyperexcitability is thought to elicit positive visual symptoms (scintillations, phosphenes). It is also believed to trigger the trigeminovascular system and the resultant migraine pain due to changes in the meningeal vessels. […] Following the wave of hyperexcitability, areas of depressed electrical activity are thought to be responsible for the accompanying visual scotoma.
#1 Ophthalmologic Manifestations of Migraines – EyeWiki
https://eyewiki.org/Ophthalmologic_Manifestations_of_Migraines
Visual aura is caused by cortical spreading depression characterized by neuronal depolarization, leading to a disruption of iron gradients and loss of membrane resistance. Increased potassium concentrations promote the spread of depolarization across neural tissue and leads to release of excitatory amino acids that potentiate the spread. However, the mechanism of cortical spreading depression initiation has not been fully elucidated. […] The pathophysiology of hallucinations in migraines remains uncertain. It has been linked to dysfunction in the parietal lobe coordinate systems and activation of the occipitotemporal region of the nondominant hemisphere. […] Lastly, patients with persistent positive visual phenomena (such as visual snow) typically have hypermetabolism in the supplementary visual cortex (lingual gyrus) of Brodmann area 19 demonstrated on imaging. Hypermetabolism of the primary visual cortex was not visualized, therefore it was suggested that processing of higher visual order was affected instead of the upstream visual input.
#1 Retinal Migraine
https://decisionpoint.medscape.com/neurology/viewarticle/920180
Retinal migraine is a very specific type of migraine aura that’s quite rare. […] The pathogenesis for retinal migraine is thought to be retinal spreading depression, which is similar to cortical spreading depression, but it happens in the retina. This has never been demonstrated officially in humans, but it has been demonstrated in the laboratory in various animals, including the chick, and I believe a rodent or two, that they have induced retinal spreading depression with this wave of depolarization that propagates along the retina similar to what we see in the brain with cortical spreading depression. […] It’s thought that in some people, they may have a component of vasospasm to the blood vessels that are supplying the retina.
#1
https://pmc.ncbi.nlm.nih.gov/articles/PMC7339700/
Retinal migraine is an ophthalmo-pathological condition described as a transient monocular scotoma or vision loss, being accompanied or followed by a headache. […] Among other causes, apparently, the major one stays the ischemia or vascular spasm in, or behind the affected eye. […] A distinction should be noted, when a confusion between the terms retinal migraine and visual migraine arises. […] The pathophysiological mechanisms still remain not completely elucidated. […] Substance P, nitrous oxide, calcitonin generated peptides have been suspected as chemical effectors in the possible pathophysiological mechanisms of retinal migraine, by exercising a non-desired effect leading to the plasma extravasation, neurogenic inflammation, vasodilatation. […] Other neuro-ophthalmological structures involved are: periaqueductal gray (PAG), locus coeruleus (LC), dorsal Raphe nucleus (DRC), retinal vasculature, and activation of the retinal-thalamic-visual pathway.
#1 Pathophysiology of Migraine | Science of Migraine
https://www.scienceofmigraine.com/pathophysiology/phases-of-migraine
Cortical spreading depression (CSD) is considered to be the primary pathophysiology behind the aura phase. […] Several neuropeptides have been implicated in the sensitization of the central and peripheral trigeminovascular system, creating a state of hypersensitivity and contributing to both pain and non-pain symptoms during the headache phase. […] Several neuropeptides, including calcitonin gene-related peptide (CGRP), have been implicated in head pain and other symptoms. […] Preclinical expression studies suggest that CGRP and its receptor are expressed in multiple anatomic regions relevant to migraine (eg, trigeminovascular and cranial parasympathetic systems). […] Clinical evidence suggests that CGRP is involved in migraine pain. […] Neuropeptides may play a fundamental role in neurogenic inflammation, and peripheral and central sensitization of the trigeminovascular and other systems.
#1 Pathophysiology of Migraine | Science of Migraine
https://www.scienceofmigraine.com/pathophysiology/phases-of-migraine
Migraine may occur as a result of a dysfunctional trigeminovascular system. […] Activation of the other central regions, which project to/from the trigeminovascular system, can also contribute to non-pain symptoms. […] Repeated activation of the trigeminovascular system over time results in a state of nervous system hypersensitivity and sustained pain. […] Feedback from a sensitized brain may potentiate pain signaling and contribute to common migraine symptoms such as photophobia, phonophobia, and cutaneous/mechanical allodynia. […] There are several neuropeptides implicated in head pain and peripheral and central sensitization of the trigeminovascular system and other systems during the headache phase. […] Preclinical studies with PACAP and CGRP suggest that both neuropeptides may also play a role in photophobia or light sensitivity that may occur during the headache phase of a migraine attack.
#1 A review on retinal migraines: the structural changes that occur on the retinal vasculature | The Aggie Transcript
https://aggietranscript.ucdavis.edu/articles/review-retinal-migraines-structural-changes-occur-retinal-vasculature
The underlying cause of retinal migraines remains largely unknown and might be due to a variety of factors. […] Most notable factors are genetic risk factors that lead to decreased blood exchange in the retina from the narrowing of blood vessels or, more severe, retinal angiopathy (bursting of red blood cells). […] While the cause of retinal migraines is still unknown, two primary contributors have begun to emerge from the literature. Researchers currently believe that depression of electrical activity in the neuron might be causing the thinning seen in the retinal nerve fiber layer (RNFL). […] The RNFL consists of axons from retinal ganglion cells. […] The thinning of this layer reflects the loss of axons and signs and symptoms of visual impairment. […] Over time, this pattern of occurrence may gradually alter the structure of both the brain and the retina negatively which leads to an abnormal change in the structure and formation of ganglion cells within the retina, potentially leading to their ultimate death.
#1 Neurovascular changes of the retina and optic nerve head in episodic migraine | Scientific Reports
https://www.nature.com/articles/s41598-024-71388-1
A case report of a patient during a migraine attack with visual aura showed narrowing of the retinal vessels and decreased radial peripapillary capillary density, superficial and deep foveal vessel density. […] Consequently, the transient and recurrent decrease in blood supply to the ONH may lead to ischemic ganglion cell death. […] Our finding, that the duration of migraine showed an inverse correlation with the VD of DCP in all quadrants and with the VD of SCP in the nasal quadrant support this concept. […] The transitory cerebral vasospasm leading to the diminution of blood supply which occurs before or during the onset of pain, is frequently localized to the posterior area of one hemisphere. […] Our results suggest for the first time the presence of significant reduction in macular vessel density on the dominant side not only compared to controls, but to the contralateral side.
#1 Looking Migraine in the Eye – Migraine Science Collaborative
https://migrainecollaborative.org/looking-migraine-in-the-eye
A non-invasive imaging tool reveals changes in the retinal microvasculature during migraine. The approach could help researchers better understand the pathophysiology of the condition and perhaps be of clinical use, too. […] Investigators from the University of California, Los Angeles, US, used a non-invasive imaging tool called optical coherence tomography angiography (OCTA) to reveal several changes in the retinal vasculature during a migraine attack and between attacks, in those having migraine with aura or migraine without aura, including alterations in the shape and blood supply of the retina. […] The authors say that retinal vasculature âsignaturesâ of the sort identified in the study could perhaps one day serve as biomarkers â objective, measurable indicators â of migraine. […] Digre said the study opens up new ways to study the pathophysiology of migraine. One area where OCTA could be particularly useful, she said, is to elucidate how autonomic features of migraine affect the retinal vasculature.
#1 Retinal Migraine: Symptoms, Causes and Treatment | AMF
https://americanmigrainefoundation.org/resource-library/retinal-migraine/
Retinal migraine is a rare type of migraine that can cause visual symptoms in one eye. Most attacks are short-lived. Learn more about the symptoms, causes and treatment options for this disease. […] There is not a known definite cause of retinal migraine. It is set off by many of the same things as migraine with aura, such as: Stress, High blood pressure, Smoking, Birth control pills, Dehydration (not enough water in the system), Low blood sugar. […] The disease has visual disturbances in one eye only. If you experience twinkling lights in your right eye, vision in your left eye will be normal. In migraine with aura, visual symptoms are present in both eyes. […] At this time, there isnât a test for retinal migraine. Therefore, diagnosis consists of your doctor ruling out other possible primary headache disorders and causes for the visual disturbance, including eye diseases.
#1 Retinal Migraine: Symptoms, Causes and Treatment
https://lonestarneurology.net/blog/retinal-migraine/
Retinal migraine is characterized by the presence of an aura with visual disturbances, which appears before the onset of headache pain. […] The basis of retinal migraine is neurological dysfunction, leading to a disruption in the work of the visual analyzer. This condition develops due to a decrease in the tone of the posterior cerebral artery. As a result, transient retinal ischemia and oxygen starvation of the brain occurs. […] The genesis of visual disturbances in migraine is associated with spasms of the central retinal artery. Changes in the vessels of the fundus reflect changes in the vessels of the brain during migraine attacks; after the end of the attack, they disappear. Pathogenetically, migraine paroxysm includes a vascular component: alternation of spasm and dilatation of a certain vascular site.
#1 Retinal migraine: Causes, symptoms, and treatment
https://www.medicalnewstoday.com/articles/314917
A retinal migraine involves repeated attacks of visual disturbances in one eye. […] The exact cause of retinal migraine remains unclear. […] According to some experts, narrowing of the arteries or veins in the eye may be the cause. […] Another possible theory is that genetics or family history of retinal migraine can play a role in its occurrence. […] The characteristics of an aura may include: flashing, sparkling, or twinkling lights; a blind spot or partial loss of vision; temporary blindness. […] The International Headache Society states that the aura may spread gradually over 5 minutes or more and last between 560 minutes. […] A migraine headache may also cause: nausea and vomiting; increased sensitivity to light; increased intolerance to sound. […] Diagnosis of retinal migraine does not involve any diagnostic tests.
#1 1.2.4 Retinal migraine – ICHD-3
https://ichd-3.org/1-migraine/1-2-migraine-with-aura/1-2-4-retinal-migraine/
Repeated attacks of monocular visual disturbance, including scintillations, scotomata or blindness, associated with migraine headache. […] 1.2.4 Retinal migraine is an extremely rare cause of transient monocular visual loss. Cases of permanent monocular visual loss associated with migraine have been described. Appropriate investigations are required to exclude other causes of transient monocular blindness.
#1 Ocular Migraine Treatment NYC | Retinal Migraine Specialists in Downtown Manhattan
https://www.myeyephysicians.com/eye-care/ocular-retinal-migraine/
The exact cause of retinal migraines is unknown, but many researchers theorize that it may be related to blood flow issues involving the retina. […] Retinal migraines may be set off by the same things that trigger migraines. […] Retinal migraines start in the retina, behind the eye. […] When you have a retinal migraine, the headache pain that follows may be throbbing, pounding or pulsing and is usually located behind the affected eye.
#1 Patient’s Guide to Visual Migraine – Brigham and Women’s Hospital
https://www.brighamandwomens.org/neurology/neuro-ophthalmology/visual-migraine
Although migraines are extremely common, their exact cause remains unknown. […] It appears likely that the visual aura relates to a phenomenon called cortical spreading depression which temporarily affects electrical impulses in the brain. […] The pain of a migraine headache probably relates to spasm or irritability of blood vessels in the brain, which are sensitive to pain (unlike the brain tissue itself, which does not have pain receptors). […] Beyond these hypotheses, however, the exact mechanism that triggers a migraine remains unknown.
#1
https://journals.lww.com/ijo/fulltext/2021/12000/glaucoma_and_optical_coherence_tomography_changes.32.aspx
Migraine is a recurrent typically unilateral pulsating headache disorder manifesting in attacks lasting 472 hours affecting 10% to 11% of people worldwide. Though considered a disorder of the central nervous system, both neural and vascular systems are implicated in migraine pathogenesis. […] The role of the trigeminovascular system in migraine pathogenesis is well understood. It mediates vasodilatation of meningeal vessels and dural extravasation of plasma protein and inflammatory mediators which in turn results in sterile inflammation and vasospasm producing the typical pulsatile headache. […] It is proposed that attacks of migraine lead to vasospasm and decreased blood flow in the retina and optic nerve. Thus, ischemia of the ocular neural tissues results in retinal ganglion cells (RGC) loss and thinning of retinal nerve fiber layer and macular layers which can be measured using optical coherence tomography (OCT). Ocular blood flow changes are involved both in the pathogenesis of glaucoma and the progression of glaucomatous damage.
#1 Pathophysiology of Migraine | Science of Migraine
https://www.scienceofmigraine.com/pathophysiology/phases-of-migraine
Sensitization of primary nociceptors and central trigeminovascular neurons may contribute to allodynia in migraine. […] Magnetic resonance imaging (MRI) studies have also demonstrated that patients with migraine and greater symptoms of allodynia may display structural abnormalities within the brainstem. […] This suggests that altered sensory processing and brainstem structure may contribute to the severity of allodynia and hypersensitivity to the pain observed in migraine. […] Retinal and trigeminal nociceptive input converge in the thalamus, which projects to the nociceptive areas of the cortex (S1/S2), which can result in the exacerbation of migraine headache by light. […] Hypersensitized visual cortex (V1/V2) may also contribute to this effect. […] The trigeminovascular system, which relays head pain signals to the brain, plays a key role in migraine pathophysiology and has components in the periphery (ie, outside the blood-brain barrier) as well as in the central nervous system (CNS) (ie, inside the blood-brain barrier).
#1 Retinal Migraine Headache | Treatment & Management | Point of Care
https://www.statpearls.com/point-of-care/28450
Based on theories and pathophysiology of retinal migraine, precipitating factors for a retinal migraine are the same for migraine, with and without aura. Factors include, but are not limited to, emotional stress, high blood pressure, and hormonal contraceptive pills, as well as exercise, being at a higher altitude, dehydration, smoking, low blood sugar, and hyperthermia. Comorbidity with lupus, atherosclerosis, and sickle cell disease increases the risk of having a retinal migraine. […] […] The pathophysiology of migraine remains controversial. One theory of ocular migraine is that it is due to vasospasm within the retinal or ciliary vasculature while others think it is a spreading depression of the neuron in the retina that is similar to the spreading depression of the cerebral cortex. The spreading depression of the cerebral cortex is usually seen in the visual aura of a classic migraine; it has been observed in patients having an episode of retinal migraine, vasoconstriction of both veins, and arteries that could be diffuse or segmental. It also can be noticed by ocular hypoperfusion on fundoscopy. Fluorescein angiography can confirm the diagnosis. The fluorescein angiogram shows delayed filling or occlusion of the central retinal artery and its branches with either a normal ciliary circulation or patchy choroidal defects and capillary dropout. […]
#1 Retinal migraine | MedLink Neurology
https://www.medlink.com/articles/retinal-migraine
Ischemia is the other mechanism commonly invoked to explain permanent monocular visual loss in the setting of migraine. […] Some studies, such as kinetic arc perimetry, measurements with flickering light stimuli, motion coherence perimetry, and measurements of contrast thresholds for static and moving stimuli, implicated both cortical and precortical visual sites. […] Minor risk factors for vascular disease were identified in only a few patients with transient and permanent monocular visual loss. They included hypertension, hyperthyroidism, pregnancy, diabetes, oral contraceptive use, smoking, and increased levels of factor VIII. These conditions were not thought to be the main cause of the visual loss.
#1 Increased risks of retinal vascular occlusion in patients with migraine and the protective effects of migraine treatment: a population-based retrospective cohort study | Scientific Reports
https://www.nature.com/articles/s41598-024-66363-9
Fifth, multiple coagulation abnormalities, such as platelet abnormalities and hypercoagulable states, have been detected in migraine patients with retinal vascular occlusion. […] Sixth, migraine patients are at a higher risk of patent foramen ovale (PFO) and carotid arterial dissection, both of which may contribute to RAO. […] Last but not least, during migraine attack, cerebral arterial vasospasm may hypothetically cause abnormal blood flow in the retina, and further contributes to acute retinal ischemia. […] The mechanism of vasospasm could explain the higher risk of TRAO we found in our migraine patients.
#1 When To Worry About Retinal Migraine: Duration, Symptoms
https://www.medicinenet.com/when_should_i_be_worried_about_a_retinal_migraine/article.htm
Retinal migraine is usually not a medical emergency. In most people, the condition is harmless, and vision returns to normal after some time. […] Irreversible visual loss is a possible complication of retinal migraine, but it is rare. There is still uncertainty about how often retinal migraine can cause permanent loss of eyesight, and currently, no studies can predict who will get affected and how. […] The headache in retinal migraine begins during or within 60 minutes of visual symptoms. […] There is a lack of consensus regarding the definition of retinal migraine. Some say it is different from visual or ocular migraine, which is accompanied by visual disturbances, including scintillations (seeing twinkling lights) and scotoma (areas of decreased or lost vision), whereas others say a retinal migraine can have these types of visual disturbances that are consistent with the International Classification of Headache Disorders.
#1 Retinal migraine | nidirect
https://www.nidirect.gov.uk/conditions/retinal-migraine
Retinal migraine is caused by the blood vessels to the eye suddenly narrowing (constricting), reducing the blood flow to the eye. […] Afterwards, the blood vessels relax, blood flow resumes and sight returns. Usually, there are no abnormalities within the eye and permanent damage to the eye is rare. […] There’s a small risk that the reduced blood flow may damage the thin layer at the back of the eye (the retina) and the blood vessels of the eye.
#1 Retinal migraine – Wikipedia
https://en.wikipedia.org/wiki/Retinal_migraine
Retinal migraine is a retinal disease often accompanied by migraine headache and typically affects only one eye. It is caused by ischaemia or vascular spasm in or behind the affected eye. […] Retinal migraine is caused by the blood vessels (that leads to the eye) suddenly narrowing (constricting), reducing blood flow to the eye, which causes aura in vision. […] Afterwards, the blood vessels relax, blood flow resumes and sight returns. Usually there are no abnormalities within the eye and permanent damage to the eye is rare. […] The visual field data suggests that there is a higher incidence of end arteriolar distribution infraction and a higher incidence of permanent visual field defects in retinal migraine than in clinically manifest cerebral infarctions in migraine with aura.
#1 A review on retinal migraines: the structural changes that occur on the retinal vasculature | The Aggie Transcript
https://aggietranscript.ucdavis.edu/articles/review-retinal-migraines-structural-changes-occur-retinal-vasculature
Irregularities of the optic nerve in the retina is of particular interest since it is seen as a main contributor to the pathology of retinal migraines. […] The primary occurrence of retinal migraines is caused by the constricted blood vessels supplying the eye, resulting in reduced blood flow to the eye. […] The pathogenesis of monocular visual loss may be explained by this reduction of blood flow as it relates to retinal migraines. […] Due to the connection with other bodily systems, patients experiencing these migraines particularly with aura are at an increased risk of heart disease, ischemic stroke, and even mortality. […] The studies concluded that the occurrence of migraines is associated with conditions that narrow or constrict blood vessels that feed into the retina, causing a blockage of blood vessels.
#1 Increased risks of retinal vascular occlusion in patients with migraine and the protective effects of migraine treatment: a population-based retrospective cohort study | Scientific Reports
https://www.nature.com/articles/s41598-024-66363-9
Migraine is known to associate with retinal vascular occlusion. […] The pathogenesis of RVO presumably follows the principle of Virchows triad for thrombogenesis, i.e., vessel damage, stasis, and hypercoagulability. […] The main cause of thrombogenesis is due to atherosclerosis of the retinal artery, which further compresses the retinal vein in the lamina cribrosa, secondarily inducing thrombosis in the vein. […] We found that migraine is associated with higher risks of retinal vascular occlusion, including RAO and RVO, as well as their subtypes. […] Though the mechanisms of migraine on retinal vascular occlusion are likely multifactorial and currently elusive, several hypotheses have been proposed. First, alterations in endothelial and arterial function, which predispose to atherosclerosis and cardiovascular diseases, constitute an important link between migraine and vascular diseases.
#1 Migraine Visual Aura & Other Visual Phenomena
https://practicalneurology.com/articles/2022-may/migraine-visual-aura-other-visual-phenomena
The presentation of monocular scotoma, transient monocular total vision loss, or field defects followed by a migraine headache, describes a very rare reversible visual phenomena known as retinal migraine. To meet diagnostic guidelines, attacks must fulfill criteria for migraine with aura and the visual symptoms should be gradual, last 60 minutes or less, and be associated with headache at onset or within 1 hour. […] Importantly, there is clinical overlap of the presenting symptoms of retinal migraine and amaurosis fugax, which is a broad term describing vascular causes of transient monocular vision loss (eg, giant cell arteritis, retinal vasospasm, or retinal embolism).9 Because retinal migraine is a very rare cause of transient monocular visual impairment, further investigation and examination should be conducted, in patients without prior history of the condition, to rule out alternative causes, such as amaurosis fugax.
#1 Migraine Variants: Overview, Pathophysiology, Epidemiology
https://emedicine.medscape.com/article/1142731-overview
Ruling out eye disease or vascular causes, especially when risk factors for arteriosclerosis exist, is important. That is, the condition must be differentiated from ocular or vascular causes of transient monocular blindness, mainly carotid artery disease. […] […] Vasoconstrictive agents such as triptans and ergots should be avoided. Pharmacologic prophylaxis has only anecdotal support; when it is considered, calcium channel blockers are preferred.
#1 Migraine Variants: Overview, Pathophysiology, Epidemiology
https://emedicine.medscape.com/article/1142731-overview
Retinal migraine (also called ophthalmic or ocular migraine) is a fairly common cause of transient monocular blindness in young adults. This disorder is manifested by recurrent attacks of unilateral visual disturbance or blindness lasting from minutes to 1 hour, associated with minimal or no headache. This phenomenon is frightening to patients, who usually seek medical help to exclude amaurosis fugax due to ischemia of the retinal arteries. […] […] Retinal migraine is thought to result from transient vasospasm of the choroidal or retinal arteries. A history of recurrent attacks of transient monocular visual disturbance or blindness, with or without a headache and without other neurologic symptoms, is suggestive of retinal migraine. A personal or family history of migraine confirms the diagnosis. […]
#1 Ocular migraine: When to seek help
https://www.mayoclinic.org/diseases-conditions/migraine-headache/expert-answers/ocular-migraine/faq-20058113
See a healthcare professional right away if you have visual symptoms that haven’t been looked at before, such as: Visual changes in only one eye. Visual changes that last less than five minutes or more than 60 minutes. Visual changes without a headache. New headaches or new visual changes. Headaches or visual changes that begin after age 50. New weakness on one side of the body or speech changes. These symptoms may suggest a more serious cause of your visual symptoms and need medical attention.
#1 Retinal Migraine: Symptoms, Causes and Treatment | AMF
https://americanmigrainefoundation.org/resource-library/retinal-migraine/
There are no clear guidelines for the management of patients with retinal migraine. Once the visual disturbance starts, it needs to run its course. Some treatments, such as triptans, can prolong the visual loss. Preventive therapies used for other migraine types can be effective. These can include medications from the following families: calcium channel blockers (reduces blood pressure), anti-seizure or antidepressant medications. Daily low-dose aspirin can also be helpful. Calcitonin gene-related peptide (CGRPâa protein that is released around the brain) is found in the retina but we donât know if medications targeting CGRP are useful for this type of migraine.
#1 Chapter 1, Episode 6: What is Ocular Migraine? – Association of Migraine Disorders
https://www.migrainedisorders.org/video/ocular-migraine/
Ocular migraine is a rare condition also known as âretinal migraineâ or retinal vasospasm. […] While visual aura of migraine comes from changes in the brain, ocular migraine is thought to be caused by blood vessels in the retina constricting or going into spasm. […] Recommended preventive medications for ocular migraine are blood pressure medications such as calcium channel blockers or beta blockers. Both of these medications decrease spasm of the blood vessels.
#1 A review on retinal migraines: the structural changes that occur on the retinal vasculature | The Aggie Transcript
https://aggietranscript.ucdavis.edu/articles/review-retinal-migraines-structural-changes-occur-retinal-vasculature
This apparent thinning of the blood vessels is a major contributor to the headache that occurs, especially in patients who have a migraine with aura versus without aura. […] This discrepancy between patients with and without aura indicates that the visual field plays a large role in the severity of the migraine, showing more significant alterations to the vascular retina in the presence of aura. […] Possible implications of these findings reveal that blood thinners or neutralizing the clots using invasive strategies could be a source for future research.
#1 Current Perspective on Retinal Migraine
https://www.mdpi.com/2411-5150/5/3/38
The vascular or vasospastic hypothesis of migraine has been largely refuted by advances in intracerebral blood flow imaging. […] While we still do not fully understand migraine, advances in the understanding of its pathophysiology indicate a complex interplay of mechanisms involving hypothalamic activation, alteration in thalamo-cortical circuits, brainstem activation, cortical spreading depolarisation, release of chemicals such as calcitonin gene-related peptide (CGRP), and pituitary adenylate cyclase activating polypeptide (PACP). […] If we accept that the visual aura is a cortical process that results in binocular symptoms, the term retinal migraine becomes potentially confusing and anatomically incongruous. […] Several authors have proposed the cortical spreading depression (CSD) theory of retinal neurons as a plausible explanation. […] Retinal migraine is a very rare cause of TMVL. […] Future research in this distinct clinical entity is needed, as the term âretinal migraineâ may be a misnomer that confuses clinicians and patients alike.
#2 Ocular Migraine: What It Is, Causes, Symptoms & Treatment
https://my.clevelandclinic.org/health/diseases/24961-ocular-migraine
Ocular migraine (also known as retinal migraine) is a condition that involves attacks of visual issues that affect one eye and migraine headaches. […] Researchers don’t know what exactly causes ocular migraines (retinal migraines), but they have theories. One of several theories is that it may be due to issues in blood vessels or blood flow that supports your retina. This issue in blood flow causes visual symptoms. Once your blood vessels relax, normal blood flow resumes and your sight returns. […] Researchers believe there’s also a genetic component to ocular migraines, as 50% of people who experience them have a family history of migraine headaches.
#2 Retinal migraine | nidirect
https://www.nidirect.gov.uk/conditions/retinal-migraine
Retinal migraine is caused by the blood vessels to the eye suddenly narrowing (constricting), reducing the blood flow to the eye. […] Afterwards, the blood vessels relax, blood flow resumes and sight returns. Usually, there are no abnormalities within the eye and permanent damage to the eye is rare. […] There’s a small risk that the reduced blood flow may damage the thin layer at the back of the eye (the retina) and the blood vessels of the eye.
#2 Ocular Migraine vs. Visual Migraine – What’s the Difference? | MigreLief
https://www.migrelief.com/ocular-migraine-vs-visual-migraine-what-is-the-difference/
Ocular or retinal migraines happen in the eye, so only affect the vision in that eye, while visual migraines occur in the brain, so affect the vision in both eyes together. […] Typically occurs in one eye and affects vision when a blood vessel in the eye spasms, resulting in a lack of blood flow. […] What causes ocular/retinal migraines? Ocular migraines occur when the blood vessels to the eyes start to constrict, or narrow. This reduces the blood flow to one of your eyes. When the migraine ends, the blood vessels relax and open up, allowing blood flow to resume and vision is restored. […] According to the World Health Organization, migraine headaches appear to be triggered by activation of a mechanism deep in the brain, which releases inflammatory substances around nerves and blood vessels in the head and brain. Imaging studies have shown changes in blood flow to the brain during ocular migraines and migraine auras. But why this happens and what brings about the spontaneous resolution of ocular migraines and visual migraines remain unknown.
#2 Seeing Stars: How to Diagnose and Manage Migraine
https://www.reviewofoptometry.com/article/seeing-stars-how-to-diagnose-and-manage-migraine
Retinal migraine is thought to result from transient vasospasm of the choroidal or retinal arteries. Rarely, when patients with retinal migraine are examined during an attack with visual loss, optic pallor or narrowing of the retinal vessels can be seen. A history of recurrent attacks of transient monocular visual disturbance or blindness, with or without a headache and without other neurologic symptoms, is suggestive of retinal migraine. […] Retinal migraine must be differentiated from ocular or vascular causes of transient monocular blindness such as carotid artery disease and coagulation disorders.
#2
https://pmc.ncbi.nlm.nih.gov/articles/PMC7339700/
The vascular theory still remains doubtful due to the complexity of retinal vascular supply. […] It is believed that retinal vasospasm initiates transient monocular visual loss, being the most plausible explanation. […] Optic nerve infarction and retinal infarction can occur due to the retinal vascular changes and the particularities during the migraine attack.
#2 Ophthalmologic Manifestations of Migraines – EyeWiki
https://eyewiki.org/Ophthalmologic_Manifestations_of_Migraines
Migraine has been hypothesized to be caused by irritation of the meninges, blood vessels, or regions supplied by the trigeminal nerve. Substance P, nitrous oxide, and calcitonin gene-related peptide have all been implicated in the possible pathophysiology of migraine as they contribute to plasma extravasation, neurogenic inflammation, and vasodilation. Other structures involved in migraine pathophysiology include the periaqueductal gray (PAG), locus coeruleus (LC), and dorsal raphe nucleus (DRN). […] The specific pathophysiology has not been elucidated for all subtypes of migraine. Basilar-type headache is presumed to be due to cortical spreading depression in the brainstem. Basilar artery pathology has not been associated with basilar-type headache. Retinal migraine is also hypothesized to involve cortical spreading depression in the retina.
#2 Ophthalmologic Manifestations of Migraines – EyeWiki
https://eyewiki.org/Ophthalmologic_Manifestations_of_Migraines
Visual aura is caused by cortical spreading depression characterized by neuronal depolarization, leading to a disruption of iron gradients and loss of membrane resistance. Increased potassium concentrations promote the spread of depolarization across neural tissue and leads to release of excitatory amino acids that potentiate the spread. However, the mechanism of cortical spreading depression initiation has not been fully elucidated. […] The pathophysiology of hallucinations in migraines remains uncertain. It has been linked to dysfunction in the parietal lobe coordinate systems and activation of the occipitotemporal region of the nondominant hemisphere. […] Lastly, patients with persistent positive visual phenomena (such as visual snow) typically have hypermetabolism in the supplementary visual cortex (lingual gyrus) of Brodmann area 19 demonstrated on imaging. Hypermetabolism of the primary visual cortex was not visualized, therefore it was suggested that processing of higher visual order was affected instead of the upstream visual input.
#2 Pathophysiology of Migraine | Science of Migraine
https://www.scienceofmigraine.com/pathophysiology/phases-of-migraine
Cortical spreading depression (CSD) is considered to be the primary pathophysiology behind the aura phase. […] Several neuropeptides have been implicated in the sensitization of the central and peripheral trigeminovascular system, creating a state of hypersensitivity and contributing to both pain and non-pain symptoms during the headache phase. […] Several neuropeptides, including calcitonin gene-related peptide (CGRP), have been implicated in head pain and other symptoms. […] Preclinical expression studies suggest that CGRP and its receptor are expressed in multiple anatomic regions relevant to migraine (eg, trigeminovascular and cranial parasympathetic systems). […] Clinical evidence suggests that CGRP is involved in migraine pain. […] Neuropeptides may play a fundamental role in neurogenic inflammation, and peripheral and central sensitization of the trigeminovascular and other systems.
#2
https://journals.lww.com/ijo/fulltext/2021/12000/glaucoma_and_optical_coherence_tomography_changes.32.aspx
Migraine is a recurrent typically unilateral pulsating headache disorder manifesting in attacks lasting 472 hours affecting 10% to 11% of people worldwide. Though considered a disorder of the central nervous system, both neural and vascular systems are implicated in migraine pathogenesis. […] The role of the trigeminovascular system in migraine pathogenesis is well understood. It mediates vasodilatation of meningeal vessels and dural extravasation of plasma protein and inflammatory mediators which in turn results in sterile inflammation and vasospasm producing the typical pulsatile headache. […] It is proposed that attacks of migraine lead to vasospasm and decreased blood flow in the retina and optic nerve. Thus, ischemia of the ocular neural tissues results in retinal ganglion cells (RGC) loss and thinning of retinal nerve fiber layer and macular layers which can be measured using optical coherence tomography (OCT). Ocular blood flow changes are involved both in the pathogenesis of glaucoma and the progression of glaucomatous damage.
#2 Ocular migraine: When to seek help
https://www.mayoclinic.org/diseases-conditions/migraine-headache/expert-answers/ocular-migraine/faq-20058113
The term „ocular migraine” can be confusing. Headache specialists don’t use this term anymore, but it has been used to describe migraines that occur with changes in vision. […] Sometimes people use the term „ocular migraine” to refer to a retinal migraine. This type of migraine is very rare and causes visual changes in one eye. When visual changes are only in one eye, they could signal something serious and may need treatment right away. […] A retinal migraine is a rare condition that usually affects people who also have other symptoms of migraine. Retinal migraine involves repeated bouts of short-lasting partial vision loss, such as blind spots. These bouts may happen before or during the headache. […] A retinal migraine unlike a migraine with aura affects only one eye, not both. But usually vision changes that affect only one eye aren’t related to a retinal migraine. Vision changes in one eye can be caused by more-serious conditions that need treatment.
#2 Ocular Migraine (Retinal Migraine) | Your Eye Health
https://www.guidedogs.org.uk/getting-support/information-and-advice/eye-health/ocular-migraine/
Retinal migraine is a rare type of migraine that causes temporary full or partial loss of vision in one eye, usually the same eye each time. […] Retinal migraine differs from migraine with aura, a more common type of migraine that causes visual disturbances. […] Ocular migraines happen when the blood vessels in the eye suddenly narrow and blood flow to the retina at the back of the eye is reduced. […] Once the blood vessels relax and the blood flow comes back, your vision returns to normal. […] There is a possible risk of complications from ocular migraine if reduced blood flow damages the retina at the back of the eye or if there is damage to the blood vessels. […] Retinal migraines can cause sudden vision loss in one eye, which, although unsettling, is usually short-lived.
#2 Migraine – Knowledge @ AMBOSS
https://www.amboss.com/us/knowledge/migraine/
Activation of the autonomic nervous system; : external physiological and emotional stimulation (e.g., hormonal changes, stress) hypothalamic response to the change in homeostasis hypothalamic neurons influence the autonomic nervous system shift toward a parasympathetic tone constriction and dilatation of intracranial, especially the meningeal, blood vessels. […] Vasodilatation is now considered an epiphenomenon rather than the primary cause of migraine headache. […] Aura consists of monocular visual phenomena (e.g., scintillation, scotoma, blindness). […] All symptoms are fully reversible. […] Aura fulfills 2 of the following criteria: Spread: gradually over 5 minutes; Duration: 5-60 minutes; Onset of headache: within 60 minutes.
#2 When To Worry About Retinal Migraine: Duration, Symptoms
https://www.medicinenet.com/when_should_i_be_worried_about_a_retinal_migraine/article.htm
Retinal migraine is usually not a medical emergency. In most people, the condition is harmless, and vision returns to normal after some time. […] Irreversible visual loss is a possible complication of retinal migraine, but it is rare. There is still uncertainty about how often retinal migraine can cause permanent loss of eyesight, and currently, no studies can predict who will get affected and how. […] The headache in retinal migraine begins during or within 60 minutes of visual symptoms. […] There is a lack of consensus regarding the definition of retinal migraine. Some say it is different from visual or ocular migraine, which is accompanied by visual disturbances, including scintillations (seeing twinkling lights) and scotoma (areas of decreased or lost vision), whereas others say a retinal migraine can have these types of visual disturbances that are consistent with the International Classification of Headache Disorders.
#2 Retinal migraine: Causes, symptoms, and treatment
https://www.medicalnewstoday.com/articles/314917
A retinal migraine involves repeated attacks of visual disturbances in one eye. […] The exact cause of retinal migraine remains unclear. […] According to some experts, narrowing of the arteries or veins in the eye may be the cause. […] Another possible theory is that genetics or family history of retinal migraine can play a role in its occurrence. […] The characteristics of an aura may include: flashing, sparkling, or twinkling lights; a blind spot or partial loss of vision; temporary blindness. […] The International Headache Society states that the aura may spread gradually over 5 minutes or more and last between 560 minutes. […] A migraine headache may also cause: nausea and vomiting; increased sensitivity to light; increased intolerance to sound. […] Diagnosis of retinal migraine does not involve any diagnostic tests.
#2 Retinal migraine
https://www.nhs.uk/conditions/retinal-migraine/
Retinal migraines are thought to happen when the blood vessels in your eye suddenly narrow, restricting the blood flow. […] Things that can cause them include: stress, caffeine and alcohol, dehydration, smoking, high blood pressure, bending over, low blood sugar, some types of hormonal contraception.
#2 Retinal migraine: Causes, symptoms, and treatment
https://www.medicalnewstoday.com/articles/314917
The medication a doctor prescribes to treat retinal migraine may depend on a person’s age and how frequently they experience retinal migraine. […] The 2021 article states that permanent vision loss can be a complication of retinal migraine. […] Prevention of retinal migraine is similar to prevention of regular migraine. […] The exact cause is still unknown.
#2
https://111.wales.nhs.uk/retinalmigraine/
Retinal migraine is caused by the blood vessels to the eye suddenly narrowing (constricting), reducing the bloodflow to the eye. […] Afterward the blood vessels relax, bloodflow resumes and sight returns. Usually there are no abnormalities within the eye and permanent damage to the eye is rare. […] There’s a small risk that the reduced bloodflow may damage the thin layer at the back of the eye (the retina) and the blood vessels of the eye. This will be monitored in your follow-up appointments. Permanent vision loss is rare.
#2 Retinal migraine – WikiProjectMed
https://mdwiki.org/wiki/Retinal_migraine
Retinal migraine is a type of headache disorder with episodes of vision problems in one eye followed by a migraine headache. Vision problems may vary from a complete loss, to blurring, to flashing lights, to a scotoma and typically last less than an hour. The underlying mechanism is unclear with theories including spasm of blood vessels supplying the eye and spreading depression of the neurons in the retina. Retinal migraine is caused by the blood vessels (that leads to the eye) suddenly narrowing, reducing blood flow to the eye, which causes aura in vision. […] The visual field data suggests that there is a higher incidence of end arteriolar distribution infarction and a higher incidence of permanent visual field defects in retinal migraine than in clinically manifest cerebral infarctions in migraine with aura.
#2 Increased risks of retinal vascular occlusion in patients with migraine and the protective effects of migraine treatment: a population-based retrospective cohort study | Scientific Reports
https://www.nature.com/articles/s41598-024-66363-9
It has been demonstrated that vascular endothelial dysfunctions are present in migraine patients and retinal vascular occlusion based on studies with biomarkers. […] Second, atrial fibrillation, which is a leading cause of cardiac emboli, was demonstrated to contribute to retinal vascular occlusion, and also significantly associated with MA. […] Third, mutations of the methylenetetrahydrofolate reductase (MTHFR) gene, including MTHFR C677T and A1298C, affect homocysteine levels, causing hyperhomocysteinemia. […] Hyperhomocysteinemia is considered to be associated with migraine and retinal vascular occlusion. […] Fourth, there is a connection between migraine and retinal vascular occlusion with hereditary cerebral small vessel diseases, including cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL), and retinal vasculopathy with cerebral leukodystrophy (RVCL).
#2 Migraine Visual Aura & Other Visual Phenomena
https://practicalneurology.com/articles/2022-may/migraine-visual-aura-other-visual-phenomena
The presentation of monocular scotoma, transient monocular total vision loss, or field defects followed by a migraine headache, describes a very rare reversible visual phenomena known as retinal migraine. To meet diagnostic guidelines, attacks must fulfill criteria for migraine with aura and the visual symptoms should be gradual, last 60 minutes or less, and be associated with headache at onset or within 1 hour. […] Importantly, there is clinical overlap of the presenting symptoms of retinal migraine and amaurosis fugax, which is a broad term describing vascular causes of transient monocular vision loss (eg, giant cell arteritis, retinal vasospasm, or retinal embolism).9 Because retinal migraine is a very rare cause of transient monocular visual impairment, further investigation and examination should be conducted, in patients without prior history of the condition, to rule out alternative causes, such as amaurosis fugax.
#2 Migraine Variants: Overview, Pathophysiology, Epidemiology
https://emedicine.medscape.com/article/1142731-overview
Retinal migraine (also called ophthalmic or ocular migraine) is a fairly common cause of transient monocular blindness in young adults. This disorder is manifested by recurrent attacks of unilateral visual disturbance or blindness lasting from minutes to 1 hour, associated with minimal or no headache. This phenomenon is frightening to patients, who usually seek medical help to exclude amaurosis fugax due to ischemia of the retinal arteries. […] […] Retinal migraine is thought to result from transient vasospasm of the choroidal or retinal arteries. A history of recurrent attacks of transient monocular visual disturbance or blindness, with or without a headache and without other neurologic symptoms, is suggestive of retinal migraine. A personal or family history of migraine confirms the diagnosis. […]
#2 1.2.4 Retinal migraine – ICHD-3
https://ichd-3.org/1-migraine/1-2-migraine-with-aura/1-2-4-retinal-migraine/
Repeated attacks of monocular visual disturbance, including scintillations, scotomata or blindness, associated with migraine headache. […] 1.2.4 Retinal migraine is an extremely rare cause of transient monocular visual loss. Cases of permanent monocular visual loss associated with migraine have been described. Appropriate investigations are required to exclude other causes of transient monocular blindness.
#2 Migraine Variants: Overview, Pathophysiology, Epidemiology
https://emedicine.medscape.com/article/1142731-overview
Ruling out eye disease or vascular causes, especially when risk factors for arteriosclerosis exist, is important. That is, the condition must be differentiated from ocular or vascular causes of transient monocular blindness, mainly carotid artery disease. […] […] Vasoconstrictive agents such as triptans and ergots should be avoided. Pharmacologic prophylaxis has only anecdotal support; when it is considered, calcium channel blockers are preferred.
#2 Retinal migraine vs. ocular migraine
https://www.medicalnewstoday.com/articles/retinal-migraine-vs-ocular-migraine
Retinal migraine is a specific type of ocular migraine that causes visual symptoms in one eye. […] Retinal migraine episodes start with visual symptoms in one eye. They occur either alongside a migraine episode or within an hour of an episode starting. […] Some research suggests that retinal migraine happens when nerves in the layer of cells at the back of the eye deactivate. […] Doctors consider retinal migraine to be a benign condition, meaning that it causes no lasting health effects, even though its symptoms can sometimes disrupt day-to-day life and be painful. […] Retinal migraine is a rare type of migraine that causes temporary vision loss and scintillation in one eye. […] Some medications for other types of migraine, like triptans, can make vision loss last longer, according to the AMF. […] It is important for an individual to speak with a doctor about retinal migraine symptoms, as they are similar to some symptoms of a stroke. Identifying stroke symptoms early can help the person seek help quickly.
#3 Retinal Migraine: Symptoms, Causes and Treatment
https://lonestarneurology.net/blog/retinal-migraine/
Retinal migraine is characterized by the presence of an aura with visual disturbances, which appears before the onset of headache pain. […] The basis of retinal migraine is neurological dysfunction, leading to a disruption in the work of the visual analyzer. This condition develops due to a decrease in the tone of the posterior cerebral artery. As a result, transient retinal ischemia and oxygen starvation of the brain occurs. […] The genesis of visual disturbances in migraine is associated with spasms of the central retinal artery. Changes in the vessels of the fundus reflect changes in the vessels of the brain during migraine attacks; after the end of the attack, they disappear. Pathogenetically, migraine paroxysm includes a vascular component: alternation of spasm and dilatation of a certain vascular site.
#3 Retinal migraine – Wikipedia
https://en.wikipedia.org/wiki/Retinal_migraine
Retinal migraine is a retinal disease often accompanied by migraine headache and typically affects only one eye. It is caused by ischaemia or vascular spasm in or behind the affected eye. […] Retinal migraine is caused by the blood vessels (that leads to the eye) suddenly narrowing (constricting), reducing blood flow to the eye, which causes aura in vision. […] Afterwards, the blood vessels relax, blood flow resumes and sight returns. Usually there are no abnormalities within the eye and permanent damage to the eye is rare. […] The visual field data suggests that there is a higher incidence of end arteriolar distribution infraction and a higher incidence of permanent visual field defects in retinal migraine than in clinically manifest cerebral infarctions in migraine with aura.
#3 Retinal Migraine
https://decisionpoint.medscape.com/neurology/viewarticle/920180
Retinal migraine is a very specific type of migraine aura that’s quite rare. […] The pathogenesis for retinal migraine is thought to be retinal spreading depression, which is similar to cortical spreading depression, but it happens in the retina. This has never been demonstrated officially in humans, but it has been demonstrated in the laboratory in various animals, including the chick, and I believe a rodent or two, that they have induced retinal spreading depression with this wave of depolarization that propagates along the retina similar to what we see in the brain with cortical spreading depression. […] It’s thought that in some people, they may have a component of vasospasm to the blood vessels that are supplying the retina.
#3 Retinal Migraine: Symptoms, Causes and Treatment | AMF
https://americanmigrainefoundation.org/resource-library/retinal-migraine/
Retinal migraine is a rare type of migraine that can cause visual symptoms in one eye. Most attacks are short-lived. Learn more about the symptoms, causes and treatment options for this disease. […] There is not a known definite cause of retinal migraine. It is set off by many of the same things as migraine with aura, such as: Stress, High blood pressure, Smoking, Birth control pills, Dehydration (not enough water in the system), Low blood sugar. […] The disease has visual disturbances in one eye only. If you experience twinkling lights in your right eye, vision in your left eye will be normal. In migraine with aura, visual symptoms are present in both eyes. […] At this time, there isnât a test for retinal migraine. Therefore, diagnosis consists of your doctor ruling out other possible primary headache disorders and causes for the visual disturbance, including eye diseases.
#3 What is an Ocular Migraine (And How Do You Treat it?)
https://www.millcreekeye.com/what-is-an-ocular-migraine-and-how-do-you-treat-it/
Retinal migraines can appear without a headache. […] While the exact cause is unknown, experts have observed that spasms in the blood vessels and nerve cells in the retinal lining at the back of the eye are associated with ocular migraine symptoms. […] Triptans can be effective for those experiencing a migraine with aura, they are not recommended for those with retinal migraines (they can prolong vision loss).