Review Article

Neuro-ophthalmic Manifestations of Coronavirus
Disease 2019 and Its Vaccination: A Narrative Review

Mohadeseh Feizi1, MD; Danielle R. Isen2, DO; Mehdi Tavakoli2, MD

1Ophthalmic Research Center, Research Institute for Ophthalmology and Vision Science, Shahid Beheshti University of Medical
Sciences, Tehran, Iran

2University of Alabama at Birmingham Heersink School of Medicine, Department of Ophthalmology and Visual Sciences,
Birmingham, Alabama, USA

ORCID:
Mohadeseh Feizi: https://orcid.org/0000-0001-8558-8074

Abstract

Coronavirus disease 2019 (COVID-19) is a current pandemic caused by SARS-CoV-2 that
has vastly affected the whole world. Although respiratory disease is the most common
manifestation of COVID-19, the virus can affect multiple organs. Neurotropic aspects of
the virus are increasingly unfolding, in so far as some respiratory failures are attributed
to brainstem involvement. The neuro-ophthalmic manifestations of COVID-19 and the
neuro-ophthalmic side effects of vaccination were reviewed. The major findings are that
the SARS-CoV-2 infection commonly causes headaches and ocular pain. It can affect
the afferent and efferent visual pathways by ischemic or inflammatory mechanisms.
Optic nerve may be the origin of transient or permanent visual loss from papillophlebitis,
idiopathic intracranial hypertension, or optic neuritis. Cerebrovascular strokes are not
uncommon and may lead to cortical visual impairment or optic nerve infarction. SARS-
CoV-2 may affect the pupillomotor pathways, resulting in tonic pupil (Adie’s syndrome) or
Horner’s syndrome. Cranial neuropathies including third, fourth, sixth, and seventh nerve
palsies have all been reported. Rhino-orbital mucormycosis superinfections in COVID-19
patients receiving steroids or other immunosuppressive therapies may result in unilateral
or bilateral visual loss and ophthalmoplegia. Autoimmune conditions such as Guillain-
Barré, Miller-Fisher syndrome, and ocular myasthenia have been reported.

Keywords: Corona Virus; COVID-19; Neuro-ophthalmology; Vaccination; Vision Loss

J Ophthalmic Vis Res 2023; 18 (1): 113–122

Correspondence to:

Mohadeseh Feizi, MD. Labbafinejad Medical Center,
Shahid Beheshti University of Medical Sciences, Boostan
9 St., Pasdaran Ave., Tehran 16666, Iran.
E-mail: mohadeseh_feizi@yahoo.com
Received: 17-11-2021 Accepted: 30-08-2022

Access this article online

Website: https://knepublishing.com/index.php/JOVR

DOI: 10.18502/jovr.v18i1.12731

This is an open access article distributed under the Creative Commons
Attribution License, which permits unrestricted use, distribution, and
reproduction in any medium, provided the original work is properly cited.

How to cite this article: Feizi M, Isen DR, Tavakoli M. Neuro-
ophthalmic Manifestations of Coronavirus Disease 2019 and
Its Vaccination: A Narrative Review. J Ophthalmic Vis Res
2023;18:113–122.

© 2023 Feizi et al. THIS IS AN OPEN ACCESS ARTICLE DISTRIBUTED UNDER THE CREATIVE COMMONS ATTRIBUTION LICENSE | PUBLISHED BY KNOWLEDGE E 113

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Neuro-ophthalmic Manifestations of COVID; Feizi et al

INTRODUCTION

Coronavirus disease-2019 (COVID-19) is a novel
β coronavirus of group 2B, first reported in
December 2019 in Wuhan city, that rapidly
disseminated all over the world, resulting in an
immense pandemic.[1] The disease presents in a
widely variable range from asymptomatic carriers
or mild infection to severe acute respiratory
syndrome (SARS), multi-organ failure, and death.
Besides respiratory distress syndrome, SARS-
CoV-2 may affect many other organs and cause
cardiac or renal injury, dermatologic conditions,
gastrointestinal symptoms, coagulopathy,
severe inflammatory reaction, and central or
peripheral nervous system involvement.[2] Up
to one-third of patients with COVID-19 have
neurological complications, and the incidence
appears to be higher in patients with more
severe infections.[3] The most common severe
neurologic manifestations of COVID-19 are acute
cerebrovascular disease and altered level of
consciousness.[4] A retrospective study in Wuhan
reported neurological symptoms in 36.4% of the
hospitalized patients.[1] Neurologic manifestations
are mainly reported to be associated with severe
cases of COVID-19.[1, 5] Moreover, COVID-19-
related cases of ischemic stroke involving
visual pathways have resulted in prolonged
hospitalizations and fatality.[6, 7] Findings have
suggested that ischemic strokes in patients with
COVID-19 disease are more severe and disabling
than strokes in the uninfected subjects.[8] In
contrast, isolated cranial neuropathies involving
the eye are typically associated with mild to
moderate COVID-19 disease that improves
spontaneously or with local protocols.[9, 10]

A recent review reported that over 4% of patients
with COVID-19 had ophthalmic findings requiring
clinical attention.[11] Based on an initial study in
Wuhan, visual impairment was described in 3 out
of 214 (1.4%) hospitalized patients with COVID-19.[1]

Various neuro-ophthalmologic manifestations
have been reported in patients with COVID-
19 infection. In this article, we reviewed
and categorized SARS-CoV-2-related neuro-
ophthalmic presentations.

Mechanisms of Neurologic Involvement in
COVID-19

Several mechanisms have been postulated for
neurologic involvement in COVID-19 disease.
Direct viral invasion, hypoxia, hypercoagulable
state, inflammatory reactions related to cytokine
storm, delayed autoantibody formation, endothelial
dysfunction, and retrograde axonal transport of the
infection via cranial and peripheral nerves (most
notably, the olfactory nerve) are the proposed
underlying mechanisms for neuro-ophthalmic
manifestations of COVID-19.[2, 5] It is thought that
direct viral invasion is mediated by viral fusion
to the angiotensin-converting-enzyme 2 (ACE-2)
receptor, which is expressed on the surface of
pulmonary type II alveolar epithelial cells as well as
neurons and glial cells.[12] The SARS-COV-2 virus
can affect nearly all neuro-ophthalmic pathways
[Table 1]. COVID-19 can cause a wide range of
pathologies within the afferent and efferent visual
pathways. SARS-CoV-2 can cause central nervous
system conditions such as seizures,[13] anosmia
or ageusia,[14] altered level of consciousness,
posterior reversible encephalopathy syndrome
(PRES),[15, 16] neuromyelitis optica (NMO)
spectrum disorder,[4, 17] myelin oligodendrocyte
glycoprotein (MOG)-associated disease,[3, 18–22]
acute disseminated encephalomyelitis (ADEM),[23]
cerebral venous sinus thrombosis (CVST),[24, 25]
and cerebrovascular strokes.[2, 6–8] It can also
affect the peripheral nervous system, leading
to conditions such as Guillain-Barré,[26] Miller
Fisher syndrome,[27, 28] polyneuritis cranialis,[28]
and myasthenia gravis.[29, 30]

SARS-CoV-2 is associated with pathologies
of the afferent visual pathways including
optic neuritis (idiopathic[5, 14, 31–33] or immune-
mediated),[3, 4, 17–22] optic nerve infarction,[34]
papillophlebitis,[35] and idiopathic intracranial
hypertension.[36–38] The efferent visual pathways
can be lesioned by COVID-19-related isolated
cranial neuropathies,[9, 27, 39–41] nystagmus,[42–46]
tonic pupil,[47–51] Horner’s syndrome,[12, 13, 52]
and opsoclonus-myoclonus-ataxia syndrome
(OMAS).[53–55] Mucormycosis infections,[56] which
are of exponentially increasing incidence in
COVID-19 patients, can occur as a superinfection
and result in lesions of the afferent or efferent
visual pathways or even both.[57, 58]

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Interval Between Infection and Neuro-
Ophthalmic Manifestations

Neuro-ophthalmic manifestations of COVID-19
may present either concurring with systemic and
pulmonary symptoms or days to several weeks
after their resolution. Timeline latency between
acute viral symptoms and neuro-ophthalmic
manifestation, auto-antibody formation, and good
response to steroid therapy favor an immune-
mediated mechanism.[49] Guillain-Barré, Miller
Fisher syndrome, NMO, MOG-associated disease,
ADEM, tonic pupil, rhombencephalitis, Bickerstaff
encephalitis, myasthenia gravis (MG), and OMAS
were all postulated to have delayed-immune
mediated mechanisms related to COVID-19.
The delayed immune response may be from
antibodies directed against SARS-CoV-2 proteins
that cross-react with cellular proteins through
a mechanism known as molecular mimicry.
Alternatively, COVID-19 infection may impair
immunologic self-tolerance.[29]

Headache/Ocular Pain

Ocular pain and headache are common and
may be the initial manifestation of COVID-19
infection.[1, 11, 59] Headache was reported in 71% and
ocular pain in 34% by healthcare workers in the
Netherlands in patients with a positive SARS-CoV-
2 polymerase chain reaction (PCR).[60] In another
study, eye pain was amongst the most common of
the ocular symptoms and seen in 16% of patients.[61]
Photophobia and itchy eyes were seen at a similar
frequency (18% and 17%, respectively).

Headache characteristics in COVID�19
patients were moderate to severe, pulsating or
pressing, bilateral, and mostly in the temporo-
parietal, forehead, or periorbital regions. It
has been postulated that an increase in pro-
inflammatory cytokines, hypoxia, or activation
of the trigeminal nerve endings from direct viral
insult or vasculopathy explain the underlying
pathophysiology of headache in COVID-19
disease.[62] However, the exact mechanism is
not clear, and viral encephalitis and meningitis
should be considered.

Overall, it seems that headache and
periocular pain are the most prevalent neuro-
ophthalmic presentations of COVID-19 but more
comprehensive epidemiological studies are

required to evaluate the prevalence of each
neurological symptom.

Optic Neuritis and Other Optic Nerve
Disorders

Optic neuritis has been reported in association with
COVID-19 infections in multiple cases where no
other etiologies have been determined.[5, 14, 31–33]
COVID-19 has also been the harbinger to optic
neuritis in NMO spectrum disorder[4, 17] and MOG-
related disease.[3, 18, 19, 21, 63, 64] Optic neuritis in
association with COVID-19 infection has also been
reported in the pediatric age group even in the
context of demyelinating conditions.[65] COVID-19-
related optic neuritis had a good response to
intravenous (IV) corticosteroid therapy in all cases
except four.[5, 14, 22, 32]

Optic neuritis was reported in conjunction
with panuveitis in one case of COVID-19, which
resulted in optic atrophy despite corticosteroid
treatment. However, the patient only received oral
prednisone without high-dose IV corticosteroids.
The authors postulated that ischemic insult due
to the prothrombotic capacity of COVID-19 or an
inflammatory reaction resulted in optic atrophy in
this case.[32]

Novi et al reported an adult patient with COVID-
19 disease and bilateral retrobulbar optic neuritis
with enhancing lesions in optic nerves, brain, and
thoracic spine, consistent with ADEM.[23]

Cerebrovascular ischemia is a known
complication of SARS-CoV-2 infection.[1] Optic
nerve infarction due to internal carotid artery
occlusion was reported in a 50-year-old COVID-
positive male by Tavakoli et al.[34] Central
retinal artery occlusion[66] or ophthalmic artery
occlusion[67] due to internal carotid artery stroke
have also been reported in COVID-19 disease.

There is one report of papillophlebitis in a
40-year-old male that occurred four weeks after
the resolution of a typical COVID-19 infection
with elevated D-dimer and fibrinogen levels. The
authors proposed that the COVID-19 cytokine
storm induced a hypercoagulable state and
thrombotic microangiopathy, increasing the risk of
papillophlebitis.[35]

Idiopathic intracranial hypertension can occur
in adults with COVID-19 disease, but it is rare,
and most of the cases have been reported in
children.[36–38] Two of these cases were associated

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Neuro-ophthalmic Manifestations of COVID; Feizi et al

with increased intracranial pressure inducing
sixth nerve palsies in idiopathic intracranial
hypertension due to COVID-19 multisystem
inflammatory syndrome in children (MIS-C).[36, 37]

Pupillary Abnormalities

Tonic (Adie’s) pupil refers to parasympathetic
denervation of the pupil sphincter, which causes
poor constriction of the pupil to the light but
the reaction to the accommodation remains
relatively spared. Tonic pupil has been reported in
association with COVID-19, including unilateral[47]
and bilateral[48] cases. One patient with COVID-19-
related bilateral tonic pupil also had inflammatory
multifocal choroiditis.[68] Additionally, Adie-Holmes
syndrome (with additional finding of loss of the
deep tendon reflexes) has been described in a
patient with COVID-19 infection.[69] Lastly, Ordás et
al reported a case of tonic pupil with contralateral
trochlear palsy in association with COVID-19
infection.[49]

Tonic pupil is often idiopathic, but it has been
associated with other infections (e.g., syphilis,
Lyme’s disease, influenza or herpes viruses),
autoimmune processes, trauma, choroidal and
orbital tumors, and surgery.[47] In each of the
above cases of tonic pupil,[47] there was a delay
(ranging from two days to one month) between
the onset of COVID-related respiratory symptoms
and development of tonic pupil. Most of the
authors hypothesized that tonic pupil in COVID-
19 is secondary to a post-viral delayed immune-
mediated injury rather than direct viral entry into
the central nervous system. Moreover, a taper of
prednisolone has been utilized for treatment with
subsequent improvement in the tonic pupil.[50]

Horner’s syndrome has also been rarely
described in COVID-19 disease.[12, 13, 52] In each
case, COVID-19 pneumonia involving the upper
part of the lungs was the suggested etiology of
Horner’s syndrome, and no other causes were
discovered with subsequent imaging studies.

Central Visual Impairment and Visual Field
Defects

COVID-19 disease can induce hypercoagulable
and inflammatory states, increasing the risk of
cerebrovascular stroke.[6, 70] There are reports of
ischemic stroke involving the visual pathways in

association with SARS-CoV-2 infection, resulting
in homonymous field defects[2] or even cortical
blindness from bilateral occipital infarcts.[7] Bondira
et al reported a patient with COVID-19 disease
and bilateral occipital strokes, resulting in a partial
right homonymous hemianopsia and difficulty with
reading.[6] Priftis et al presented a COVID-positive
patient with a left occipito-temporal ischemic
stroke, resulting in alexia without agraphia
syndrome and right homonymous hemianopsia.[8]

COVID-induced PRES has been reported,
resulting in transient cortical visual loss[15] or even
hallucinatory palinopsia.[16] COVID-associated
CVST has also been described but is uncommon,
and only a few cases have been associated
with blurry vision and papilledema.[24, 25] The
disproportionally low frequency of reported visual
involvement in COVID-associated CVST may be
because of the severity of other symptoms or an
altered level of consciousness.

In addition, there are reports of visual loss due to
pituitary apoplexy in the context of acute COVID-19
infection.[71, 72]

Cranial Nerve Palsies and Double Vision

Damage to third, fourth, sixth, and seventh cranial
nerves have all occurred in timeline relation to
COVID-19 infection. Cranial nerve involvement may
develop as a primary and isolated insult or in the
context of a more generalized condition such as
Miller Fisher syndrome, Guillain-Barré, myasthenia
gravis, venous sinus thrombosis, and increased
intracranial pressure.

Isolated oculomotor palsy with and without
pupillary involvement has been reported in
association with COVID-19.[39, 40, 73] Similarly,
isolated abducens palsy has been described
in COVID-19.[9, 27] In these cases, there was no
enhancement of the abducens nerve pathway
on MRI, and patients had underlying systemic
hypertension. Such findings raised the hypothesis
that uncontrolled hypertension in the acute viral
illness may cause abducens palsy. An alternative
theory was that the abducens palsies occurred
from the leptomeningeal invasion of SARS-CoV-2,
given that two of these cases had optic nerve
sheath enhancement on MRI. As previously
mentioned, there is one case of unilateral trochlear
nerve palsy with contralateral tonic pupil[49] and
another with bilateral trochlear nerve palsy in the
setting of COVID-related cerebral vasculitis.[74]

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Neuro-ophthalmic Manifestations of COVID; Feizi et al

Table 1. A summary of reported neuro-ophthalmic manifestations of COVID-19.

Clinical entity Clinical characteristics References

Headache and ocular pain Common and may be the initial manifestations.
Moderate to severe, pulsating/pressing, bilateral,
temporo-parietal, forehead, or periorbital regions.

Mao L et al[1], 2020; Chwalisz BK et al, 2020[11];
Huang C et al[59], 2019

Optic neuritis Unilateral or bilateral, may be associated with
neuromyelitis optica (NMO) spectrum disorders,
myelin oligodendrocyte (MOG)-related disease,
panuveitis, acute disseminated encephalomyelitis
(ADEM).

Caudill GB et al [31], 2020; Benito-Pascual B et
al[32], 2019; Marcos Aet al[5], 2020;
Rodríguez-Rodríguez MS et al[14], 2021; Deane
K et al[33], 2021; Novi G et al[23], 2020

Optic nerve infarction Vision loss due to internal carotid artery occlusion,
optic nerve ischemia revealed on DWI sequence.

Tavakoli et al[34], 2019

Papillophlebitis Decreased visual field sensitivity, dilated and
tortuous retinal vessels, disc edema, and retinal
hemorrhage; decreased vision due to macular
edema.

Insausti-García A et al[35], 2020

Idiopathic intracranial
hypertension

More reported in children than adults due to
multisystem inflammatory syndrome (MIS).

Verkuil LD et al[36], 2020; Sofuoğlu AI et al[37],
2021; Khalid MF et al[38], 2021

Tonic Adie’s pupil Unilateral or bilateral, associated with multifocal
choroiditis; trochlea palsy.

Gopal M et al[47], 2021; Quijano-Nieto BA et
al[48], 2021; Ortiz-Seller A et al[68], 2020; Kaya
Tutar N et al[69], 2021; Ordás CM et al[49], 2020

Horner syndrome Associated with pneumonia involving the upper
part of the lung.

Popiołek A et al[52], 2021; Naor MS et al[12],
2021; Portela-Sánchez S et al[13], 2021

Visual field defect and
central visual impairment

Cerebrovascular stroke resulting in homonymous
visual field defect, cortical visual blindness,
reading difficulties.

Tisdale AK et al[70], 2020; Bondira IP et al[6],
2021; Cyr DG et al[7], 2020; Priftis K et al[8],
2021

Posterior reversible
encephalopathy syndrome
(PRES)

Transient cortical visual loss and hallucinatory
palinopsia.

Kaya Y et al[15], 2020; Ghosh R et al[16], 2020

Cranial nerve palsy Isolated or multiple cranial nerve involvement
including third, fourth, sixth, and seventh. Can
occur in the context of Miller Fisher syndrome,
Guillain-Barré, myasthenia gravis, venous sinus
thrombosis, and increased intracranial pressure.

Ordás CM et al[49], 2020; Douedi S et al[39],
2021; Cicalese MP et al[73], 2022; John C et
al[40], 2020; Greer CE et al[9], 2020; Dinkin M
et al[27], 2020; de Oliveira R de MC et al[74],
2020; Gutiérrez-Ortiz C et al[28], 2020;
Sansone P et al[26], 2021; Restivo DA et al[29],
2020; Mas Maresma L et al[30], 2020; Lima MA
et al[10], 2020; Juliao Caamaño DS et al[75],
2020

Nystagmus and abnormal
ocular movement

Acquired nystagmus due to acute labyrinthitis,
benign paroxysmal positional vertigo,
rhombencephalitis, Bickerstaff encephalitis,
opsoclonus-myoclonus-ataxia syndrome (OMAS).

Perret M et al[42], 2021; Picciotti PM et al[43],
2021; Wong P et al[44], 2022; Llorente Ayuso L
et al[45], 2021; Nelson JL et al[53], 2022;
Emamikhah M et al[54], 2021

Rhino-orbital-cerebral
mucormycosis (ROCM)

Mostly occurs in patients receiving high-dose
corticosteroid; presented with peri-ocular edema,
vision loss, ptosis, and ophthalmo-paresis.

Sen M et al[57], 2021; Pakdel F et al[58], 2022

Different medications for COVID-19-related
cranial neuropathies such as hydroxychloroquine,
azithromycin, corticosteroids, and IV
immunoglobulin have been used. However, it
is not known whether the neuro-ophthalmic
benefit was conferred.

Cranial neuropathy in relation to COVID-19
has also been seen in the context of Miller Fisher
syndrome, Guillain-Barré, and polyneuritis cranialis.
Dinkin et al described a case of presumed Miller
Fisher syndrome in a COVID-positive patient with a
partial left pupil involving oculomotor nerve palsy,

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Neuro-ophthalmic Manifestations of COVID; Feizi et al

bilateral abducens palsy, hyporeflexia, and gait
ataxia.[27] The deficits partially improved following
IV immunoglobulin infusions. Gutiérrez-Ortiz et al
detailed a similar case of Miller Fisher syndrome
in a patient with right fascicular oculomotor
palsy, right internuclear ophthalmoparesis, ataxia,
areflexia, albuminocytologic dissociation, anosmia,
ageusia, and positive reverse transcriptase-PCR
for SARS-CoV-2. Most of the deficits were resolved
following IV immunoglobulin infusions. These
authors described a second COVID-positive
case with bilateral abducens palsy, areflexia, and
albuminocytologic dissociation without ataxia
or limb weakness secondary to polyneuritis
cranialis.[28]

In a systematic review published by Sansone
et al, of the 41 patients with SARS-CoV-2-related
Guillain-Barré syndrome, 9 (22%) had diplopia, 7
(17%) had ocular palsy, and 13 (32%) had facial palsy.
The average time between the onset of SARS-
CoV-2 symptoms and the first neurological signs of
Guillain-Barré syndrome was 10 days.[26]

COVID-19 has also been the harbinger of
new diagnoses of myasthenia gravis. Restivo
et al detailed three patients who developed
diplopia, ptosis, or dysphagia and tested positive
for elevated serum acetylcholine receptor
antibodies following the SARS-CoV-2 infection.[29]
Fatigability and other myasthenic symptoms
started four to seven days after the initial COVID-
19 manifestations.[29, 30] Similarity between SARS-
CoV-2 epitopes and neuromuscular junction
components is postulated to induce molecular
mimicry, resulting in auto-antibody formation
and subsequently post-COVID-19 myasthenia
gravis.[29] Isolated peripheral facial nerve palsy
has also been reported either during or at the
onset of the SARS-CoV-2 clinical course. In one
of the eight peripheral facial nerve palsy cases
reported by Lima et al, ipsilateral abducens palsy
was also present.[10] Facial diplegia has also
been reported as a parainfectious complication
of COVID-19 disease and was considered a rare
variant of Guillain-Barré syndrome in the setting of
concomitant albuminocytologic dissociation.[75]

Abnormal Ocular Movements and Nystagmus

Acquired nystagmus has been seen in
association with COVID-19,[76] and may be due
to various underlying etiologies including acute

labyrinthitis,[42] benign paroxysmal positional
vertigo,[43] rhombencephalitis,[44] and Bickerstaff
encephalitis.[45]

Several cases of OMAS have been described in
COVID-positive patients.[53–55] In all patients who
were tested, work-up with a paraneoplastic panel
was unrevealing for other causes of OMAS. A
variety of infections besides SARS-CoV-2 including
human immunodeficiency virus (HIV), West Nile
virus, Epstein Barr virus, and enterovirus have
also been associated with OMAS.[53] Treatments
used for COVID-associated OMAS include various
combinations of the following: IV immunoglobulin,
levetiracetam, sodium valproate, clonazepam, and
corticosteroids. All cases were associated with a
good therapeutic response and partial to complete
recovery. Emamikhah et al stated that the dramatic
effect of immunotherapy on recovery suggests an
immune-mediated parainfectious mechanism for
COVID-related OMAS.[54]

Neuro-Ophthalmic Presentation Due to
Secondary Mucormycosis

There is strong evidence that infection with
SARS-CoV-2 increases the risk of secondary
fungal infections, notably rhino-orbital-cerebral
mucormycosis (ROCM). The incidence of ROCM
increased to epidemic proportions during the
second wave of the COVID-19 pandemic in
India.[57] A retrospective, observational study was
conducted in India involving 2826 patients with
COVID-associated ROCM. The most common
primary signs included periocular/facial edema
(33%), loss of vision (21%), ptosis (12%), and
proptosis (11%). Ocular movement restriction and
diplopia were infrequent signs (3%). Most (87%) of
the patients had received systemic corticosteroids
prior to developing COVID-associated ROCM, and
it was the most common risk factor for the condition
followed by diabetes mellitus.

Neuro-Ophthalmic Complications of COVID-
19 Vaccines

There are several reports of neuro-
ophthalmic complications following COVID-19
vaccination.[77–79] These complications occurred
after all types of vaccines. They include acute
ischemic stroke, intracranial hemorrhages,
and cerebral venous sinus thrombosis.[78, 80]

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Other reported neuro-ophthalmic complications
include: bilateral arteritic anterior ischemic
optic neuropathy (AAION),[81] post-vaccination
cranial neuropathy, that is, third[73] and sixth[82–84]
nerve palsies, facial palsy,[84–87] multiple cranial
nerve palsies,[88] pupillary abnormalities such as
Horner’s syndrome, Holmes-Adie pupil, miosis
and mydriasis,[78] eight nerve involvement and
benign paroxysmal positional vertigo,[89] and
post-vaccination optic neuritis.[90–92] In multiple
sclerosis patients, BNT162b2 mRNA vaccine was
reported to be associated with a transient increase
of MS symptoms in 3.8% but none of them needed
treatment.[93]

SUMMARY

Coronavirus Disease 2019 and also all types of
vaccines that have been made against it can
affect the afferent and efferent visual pathways by
ischemic or inflammatory mechanisms. The optic
nerve may be the origin of transient or permanent
visual loss from papillophlebitis, idiopathic
intracranial hypertension, or optic neuritis.
Cerebrovascular strokes are not uncommon
and may lead to cortical visual impairment. The
pupillomotor pathways and cranial nerve including
the third, fourth, sixth, and seventh nerve may
also be involved. Early detection of the neuro-
ophthalmic features of COVID-19 disease/vaccine
will assist in preventing vision loss and oculomotor
deficits.

Financial Support and Sponsorship

This article is authors’ own work and has no
sources of support.

Conflicts of Interest

The authors have no financial interest in the subject
of this article.

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