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A focal epilepsy arising from an epileptic focus in the occipital lobe, characterized by visual hallucinations, ictal blindness, and abnormal eye movements. It accounts for 5–10% of all epilepsies, and clinical differentiation from migraine is important.

Diagnostic criteria, differential diagnosis, and treatment of occipital neuralgia (paroxysmal occipital pain derived from C2 and C3 nerves). From nerve blocks and pharmacotherapy to the latest hydrodissection.

A rare hereditary macular dystrophy characterized by progressive central vision loss despite normal fundus findings. Mutations in the RP1L1 gene are the main cause, also known as Miyake disease.

This article explains the principles and algorithms of optical coherence tomography angiography (OCTA), and its clinical significance in glaucoma diagnosis including vessel density assessment, microvascular dropout, longitudinal progression assessment, and postoperative evaluation.

OCT angiography (OCTA) is a non-invasive imaging technique that three-dimensionally visualizes fine retinal and choroidal blood vessels without the use of contrast agents. This article explains the principles, indications, clinical findings, and limitations of OCTA in the field of neuro-ophthalmology.

Immune-related adverse events in the eye and orbit caused by immune checkpoint inhibitors (ICIs) used in cancer immunotherapy. They present with various conditions such as dry eye, uveitis, orbital myositis, and retinal vasculitis.

Ocular bee injuries are eye injuries caused by stings from honeybees or hornets, which can lead to complications such as toxic keratopathy, optic neuritis, glaucoma, and cataracts. Removal of the stinger, steroid treatment, and close follow-up are important.

This article explains the classification of ocular burns caused by high-temperature substances (first to third degree), the Kinoshita classification for evaluating corneoconjunctival damage, and treatment from acute-phase cooling to ocular surface reconstruction.

An intraocular infection associated with candidemia, presenting a variety of clinical manifestations from chorioretinitis to endophthalmitis. Early diagnosis and treatment can lead to good visual prognosis, while advanced cases may result in severe visual impairment.

This section explains ocular changes such as optic disc edema, choroidal folds, and RNFL thickening observed in head-down tilt bed rest (HDTBR), a ground-based analog model of spaceflight-associated neuro-ocular syndrome (SANS).

Explains eye diseases associated with atopic dermatitis. Characteristic star-shaped opacity of atopic cataract, risk of retinal detachment and keratoconus, prevention of eye scratching, and importance of collaboration with dermatology.

An ophthalmology specialist explains the symptoms, diagnosis, and treatment of ocular complications (neuroretinitis, Parinaud syndrome, etc.) caused by cat scratch disease (Bartonella henselae infection).

An ophthalmology specialist explains the symptoms, diagnosis, and treatment of ocular complications (such as uveitis, keratitis, and optic neuropathy) caused by Chikungunya virus (CHIKV) infection.

This article explains the symptoms, diagnosis, and treatment of ocular complications in epidermolysis bullosa (EB), including corneal erosion, ectropion, and symblepharon. It covers the relationship between the four major disease types and ocular findings.

This article explains ocular complications associated with neurofibromatosis type 1 (NF1 / von Recklinghausen disease). Major findings include iris Lisch nodules, optic glioma, glaucoma, and eyelid/orbital neurofibromas. Regular ophthalmic examinations from childhood and long-term management are necessary.

This article explains ocular complications associated with neurofibromatosis type 1 (NF1/von Recklinghausen disease). Major findings include iris Lisch nodules, optic pathway glioma, glaucoma, and eyelid/orbital neurofibromas. Regular ophthalmic examinations from childhood and long-term management are necessary.

This article explains the types, frequency, diagnosis, and treatment of ophthalmic complications associated with Down syndrome (trisomy 21). Patients present with various ocular findings such as strabismus, refractive errors, keratoconus, and cataracts, making regular pediatric ophthalmologic screening important.

Ocular corticosteroid therapy includes five routes: eye drops, subconjunctival, sub-Tenon's, intracameral, and intravitreal. It is the first-line treatment for uveitis and postoperative inflammation, but caution is needed for steroid-induced glaucoma and cataracts, and it should be avoided in infectious inflammation. This article systematically explains the drugs, doses, indications, and side effects for each route.

An infectious disease caused by the larval stage of Taenia solium parasitizing the eye or orbit. It is a preventable cause of blindness in endemic areas. Diagnosis relies on imaging (ultrasound, CT, MRI) and treatment primarily involves albendazole.

A rare complication primarily involving retinal hemorrhage that occurs after intervention associated with rapid intraocular pressure reduction. Often asymptomatic and resolves spontaneously.

This article explains the indications, surgical technique, postoperative care, and comparison with enucleation for evisceration. It is a procedure that preserves the scleral shell and extraocular muscles while removing only the contents of the eye, and it offers advantages for prosthetic eye movement and appearance.

Leptospirosis is a zoonotic infection caused by a Gram-negative bacterium of the spirochete group, presenting various ocular findings such as non-granulomatous uveitis with hypopyon and panuveitis.

Multiple endocrine neoplasia (MEN) is a group of rare hereditary disorders in which neoplasms develop in two or more endocrine glands. In MEN type 2B, marked thickening of corneal nerves, neuromas of the conjunctiva and eyelids, and dry eye are characteristic ocular findings. In MEN type 1, visual field defects due to pituitary tumors may occur.

Explanation of ocular complications caused by Rift Valley fever virus (RVFV). It is a mosquito-borne zoonotic disease, with macular and perimacular retinitis as characteristic ocular findings. Permanent vision loss occurs in 40–50% of cases with retinal complications.

Systemic capillary leak syndrome (Clarkson disease) is a rare disorder characterized by sudden leakage of fluid and protein from capillaries into tissues, causing various ocular complications such as conjunctival edema, choroidal effusion, acute angle closure, and NAION.

Hereditary hemorrhagic telangiectasia (HHT, Osler-Weber-Rendu disease) is an autosomal dominant vascular malformation disorder that presents with various ocular findings, including conjunctival and retinal telangiectasias and orbital arteriovenous malformations.

Mucopolysaccharidosis (MPS) is a group of diseases caused by genetic deficiencies of lysosomal enzymes, leading to accumulation of glycosaminoglycans in ocular tissues. Main ocular findings include corneal opacity, glaucoma, retinopathy, and optic disc abnormalities, with different characteristics depending on the type.

Ocular graft versus host disease (oGVHD) develops after allogeneic hematopoietic stem cell transplantation and causes severe dry eye, corneal ulcers, and conjunctival scarring. This article explains the latest findings including tear biomarkers and mesenchymal stem cell therapy.

Definition of ocular hypertension, risk stratification based on OHTS/EGPS, predictors of progression to POAG, central corneal thickness and corneal hysteresis, thresholds for follow-up and treatment initiation, SLT, preservative-free formulations, and management of secondary ocular hypertension.

Ocular symptoms of a systemic vascular disease that threatens vision, caused by ocular hypoperfusion due to severe carotid artery stenosis or occlusion. Characterized by iris rubeosis and retinal artery narrowing, and can be a precursor to cerebral infarction.

Comprehensive overview of various ocular complications associated with HIV infection. Covers the pathology, diagnosis, and treatment of HIV retinopathy, cytomegalovirus retinitis, opportunistic infections, malignancies, and immune recovery uveitis (IRU) that appear according to CD4-positive T lymphocyte count.

This article provides an overview of ocular manifestations associated with mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS). It focuses on the diagnosis and management of various ocular findings, including pigmentary retinopathy, optic atrophy, and progressive external ophthalmoplegia.

Alkaptonuria (AKU) is a rare autosomal recessive disorder caused by accumulation of homogentisic acid, presenting with characteristic bluish-black pigmentation (ochronosis) of the sclera, conjunctiva, and cornea. Treatment advances including nitisinone are discussed.

Coccidioidomycosis (Valley fever) is a systemic fungal infection caused by the dimorphic fungus Coccidioides. Ocular manifestations are rare but can cause severe intraocular inflammation when disseminated. It is endemic in the southwestern United States. Evaluation of extraocular symptoms and antifungal therapy are the mainstays of treatment.

Cutaneous T-cell lymphoma (CTCL) is a non-Hodgkin lymphoma in which malignant T cells infiltrate the skin, and can cause ocular symptoms such as seborrheic blepharoconjunctivitis, cicatricial ectropion, and madarosis of the eyelids and conjunctiva.

Various ocular manifestations associated with DiGeorge syndrome caused by 22q11.2 microdeletion. It presents a wide range of ocular complications including retinal vascular tortuosity, posterior embryotoxon, eyelid abnormalities, and microphthalmia.

Overview of ocular complications associated with familial Mediterranean fever (FMF). This article describes the various ocular symptoms reported in FMF, including episcleritis, uveitis, retinal vasculitis, and amyloid-related eye diseases, as well as their management.

Classification, clinical findings, diagnosis, and treatment of ocular manifestations associated with HLH. Retinal hemorrhage is the most common, and various ocular complications have been reported.

Multiple myeloma (MM) is a hematologic malignancy caused by the proliferation of malignant plasma cells, leading to symptoms in multiple ocular sites including the orbit, retina, cornea, and optic nerve. The pathophysiology is broadly divided into two categories: direct infiltration of tumor cells and hyperviscosity due to hyperimmunoglobulinemia.

Osteogenesis imperfecta (OI) is an inherited connective tissue disorder caused by mutations in type I collagen genes. It presents with various ocular complications such as blue sclera, glaucoma, and retinal detachment, making regular ophthalmologic follow-up important.

This article explains the symptoms, diagnosis, and treatment of ocular complications associated with psoriasis (dry eye, blepharitis, uveitis, cataracts, etc.). Approximately 10% of psoriasis patients develop ocular symptoms, and immune abnormalities via the IL-23/Th17 pathway serve as a common pathological basis.

Ocular involvement in an autoimmune disease characterized by recurrent inflammation of cartilage. Mainly scleritis, episcleritis, anterior uveitis, and peripheral corneal ulcers. Differentiation from Behçet's disease is important.

An infectious disease of ocular tissues caused by Treponema pallidum. It presents with various ocular signs such as uveitis, retinitis, and optic neuritis, and is known as the "great imitator," requiring differentiation from other diseases.

Systemic lupus erythematosus (SLE) is an autoimmune disease that causes chronic inflammation in multiple organs, with ocular symptoms occurring in approximately 30–50% of patients. It presents with various ocular lesions such as dry keratoconjunctivitis and lupus retinopathy, and in severe cases can lead to visual impairment.

Explanation of ocular manifestations associated with tuberous sclerosis complex (TSC). Comprehensive description of retinal astrocytic hamartomas, optic nerve hamartomas, anterior segment findings, and neuro-ophthalmic complications.

Xeroderma pigmentosum (XP) is an autosomal recessive genetic disorder caused by a defect in DNA repair, and ophthalmic abnormalities are seen in 93% of patients. It causes a wide range of ocular manifestations, from photophobia and corneal opacity to conjunctival squamous cell carcinoma, and UV protection and early tumor detection are central to management.

Ocular motility testing is a series of tests used to evaluate eye movement range, eye position, and double vision. It explains the visual inspection of eye movements, recording eye movement disorders with a Hess chart (Hess red-green test), the principles, procedure, and interpretation of gaze field testing, and typical findings in common diseases.

A neuro-ophthalmic disorder in which voluntary eye movements (especially saccades) cannot be initiated intentionally. It is broadly classified into congenital (Cogan type) and acquired forms, often associated with hereditary ataxias and neurodegenerative diseases.

Ocular mucous membrane pemphigoid (ocular cicatricial pemphigoid, OCP) is an autoimmune disease in which autoantibodies against adhesion components of the conjunctival basement membrane cause chronic progressive scarring. Disease progression is assessed using the Foster classification stages I to IV, and early systemic immunosuppressive therapy determines visual prognosis.

This article explains the diagnosis and treatment of ocular myasthenia gravis, a form of myasthenia gravis (an autoimmune disease of the neuromuscular junction) that is limited to extraocular muscle symptoms such as ptosis and diplopia. It is characterized by diurnal fluctuation and easy fatigability, and early treatment is important to prevent progression to the generalized form.

A rare ocular motor disorder characterized by intermittent tonic spasms of the extraocular muscles. It causes paroxysmal diplopia and often occurs after intracranial radiation therapy.

Chronic pain that persists despite minimal organic findings in the cornea or ocular surface. It is classified into peripheral and central types, differentiated by proparacaine test and IVCM. Stepwise topical and systemic treatment is performed.

A rare condition involving recurrent laryngeal nerve compression (hoarseness) due to large-vessel vasculitis (e.g., giant cell arteritis) accompanied by ocular ischemia. There is a risk of blindness, and prompt steroid treatment is required if suspected.

An autoimmune disease in which autoantibodies against the conjunctival basement membrane cause chronic conjunctivitis and progressive scarring. Without treatment, it leads to symblepharon, corneal opacity, and blindness.

A rare zoonotic infection caused by larvae of the Pentastomida class parasitizing the eye. Infection occurs through ingestion of snake meat in endemic areas of Africa and Southeast Asia, and the larvae invade the anterior chamber, vitreous body, or subretinal space, causing severe visual impairment.

Ocular rosacea is the ocular form of rosacea, causing chronic blepharitis, meibomian gland dysfunction, and keratitis. It is managed with stepwise eyelid hygiene and medication, but if left untreated, it can lead to corneal scarring and perforation.

This article explains ocular side effects of anticancer drugs (5-FU, taxanes, etc.), molecular targeted drugs (MEK inhibitors, EGFR inhibitors, etc.), immune checkpoint inhibitors, hormone therapy (tamoxifen), and immunomodulators (HCQ, interferon) by drug category.

Explains symptoms, causes, diagnosis, and treatment of ocular siderosis caused by retained iron-containing intraocular foreign bodies. Includes data on severity assessment by ERG and surgical outcomes.

This article provides an overview of ocular signs caused by systemic autoimmune diseases, focusing on optic neuritis, ischemic optic neuropathy, retinal vasculitis, orbital inflammatory syndrome, occlusive retinal vasculopathy, and amaurosis fugax.

This article explains the diagnosis and management of ocular signs such as lagophthalmos, dry eye, visual impairment, and intracranial hypertension associated with anorexia nervosa, bulimia nervosa, and binge eating disorder.

Heparin-induced thrombocytopenia (HIT) is an immune-mediated reaction to heparin administration that causes thrombosis and bleeding, leading to ocular complications such as retinal vascular occlusion, orbital hemorrhage, and homonymous hemianopia. It is characterized by a paradoxical increase in thrombosis despite a decrease in platelet count.

This article explains the characteristics, differential diagnosis, and treatment of ocular symptoms associated with migraine (such as scintillating scotoma, photophobia, and retinal migraine). Patients with visual aura should also be aware of the risk of stroke.

Thrombotic thrombocytopenic purpura (TTP) is a rare hematologic disorder characterized by microangiopathic hemolytic anemia and thrombocytopenia, with ocular signs such as retinal hemorrhage, vascular occlusion, and serous retinal detachment occurring in 14–20% of cases.

Antibody-drug conjugates (ADCs) are a new generation of anticancer drugs, but they can cause ocular surface adverse events such as microcystic epithelial changes (MECs), conjunctivitis, and limbal stem cell dysfunction. Management involves regular ophthalmic examinations and dose adjustments.

This article explains the pathophysiology, prevalence, diagnosis, and management strategies for ocular surface disease (dry eye, superficial punctate keratitis, meibomian gland dysfunction) caused by glaucoma medications (especially those containing BAK).

The ocular surface microbiome is a community of bacteria, fungi, and viruses that reside on the conjunctiva and cornea, involved in maintaining homeostasis and immune regulation. Dysbiosis is associated with many ocular diseases such as dry eye, keratitis, and meibomian gland dysfunction.

This article explains the indications, surgical techniques (CLAu, SLET, CLET, COMET), pathophysiology, and latest research on ocular surface reconstruction for limbal stem cell deficiency (LSCD).

A general term for dysplasia to malignant tumors arising from squamous epithelial cells of the ocular surface. It ranges from mild intraepithelial neoplasia to invasive squamous cell carcinoma, with risk factors including UV exposure, HIV, and HPV infection.

Sick House Syndrome often causes eye symptoms such as eye strain, dry-eye-like symptoms, and conjunctival redness due to volatile organic compounds (VOCs) such as formaldehyde. Avoiding exposure to the causative substances is the most important treatment and prevention measure.

This article explains ocular changes in the retina, optic nerve, lens, and tears associated with Alzheimer's disease (AD) and their potential as biomarkers through non-invasive retinal imaging.

A systemic zoonotic infection caused by Brucella species that spreads to the eye, causing uveitis, chorioretinitis, optic neuritis, and other conditions. Early diagnosis in endemic areas and appropriate antibiotic treatment are key to preserving vision.

This article explains ocular complications associated with facioscapulohumeral muscular dystrophy (FSHD), including retinal vasculopathy, Coats-like disease, and lagophthalmos.

Ocular complications associated with hemorrhagic fever with renal syndrome or hantavirus pulmonary syndrome caused by hantavirus. Various ocular findings such as myopic shift, intraocular pressure changes, and subconjunctival hemorrhage may occur, but most are transient and resolve spontaneously.

A specialized explanation of ocular complications (uveitis, scleritis, keratitis, dry eye) associated with hidradenitis suppurativa (HS), including symptoms, diagnosis, and treatment. The effectiveness of anti-TNF-α therapy and the importance of regular ophthalmologic screening are also introduced.

This article explains the clinical findings, pathophysiology, and potential as biomarkers of eye movement disorders (saccadic abnormalities, pursuit deficits, fixation abnormalities) and retinal thinning associated with Huntington's disease.

This article explains the symptoms, diagnosis, and treatment of ocular complications (ectropion, exposure keratopathy, MGD, fleck corneal dystrophy) associated with ichthyosis (vulgaris, X-linked, lamellar, harlequin). It introduces differences in ocular findings among types and key management points.

This article explains ocular side effects of isotretinoin (13-cis-RA) including dry eye, meibomian gland dysfunction, blepharitis, corneal abnormalities, and retinal disorders. It covers dose relationship, diagnosis, treatment, and prevention.

Kawasaki disease (mucocutaneous lymph node syndrome) is an acute vasculitis primarily affecting children, presenting characteristic ocular findings such as bilateral bulbar conjunctival injection and anterior uveitis. Early recognition of ocular symptoms prevents diagnostic delay and directly contributes to the prevention of coronary artery complications.

Moyamoya disease (MMD) is a chronic cerebrovascular disorder characterized by progressive stenosis of the terminal portion of the internal carotid artery, and may present with ocular symptoms such as transient monocular vision loss, central retinal artery occlusion, ocular ischemic syndrome, and morning glory syndrome.

Mucolipidosis (ML I–IV) is a group of inherited storage disorders caused by defects in lysosomal enzyme transport or function, with varying ocular manifestations depending on the subtype. ML I is characterized by a macular cherry-red spot, while ML IV features early corneal opacities and progressive retinal dystrophy.

Description of ocular symptoms associated with myotonic dystrophy (DM). This article describes a wide range of ophthalmic complications and their management, including cataracts, ptosis, ocular motility disorders, ocular hypotension, and Fuchs endothelial corneal dystrophy.

Osteopetrosis is a hereditary bone sclerosing disease caused by dysfunction of osteoclasts, leading to ocular symptoms such as compressive optic neuropathy due to optic canal stenosis, proptosis, and cranial nerve palsy.

Paraneoplastic syndrome (PNS) is a group of diseases caused by an immune response to tumor antigens that cross-react with normal retina and optic nerve, without direct invasion by the malignant tumor. Representative conditions include cancer-associated retinopathy (CAR) and melanoma-associated retinopathy (MAR), and ocular symptoms often precede the diagnosis of cancer.

A group of inherited metabolic disorders caused by abnormalities in peroxisome (organelle) formation, leading to systemic symptoms. Includes several types such as Zellweger syndrome and Refsum disease, and causes various ocular complications including retinitis pigmentosa, cataracts, and corneal opacity.

Ocular complications in phakomatoses (neurocutaneous syndromes) are explained by disease. Covers ocular findings, diagnosis, and treatment of neurofibromatosis, tuberous sclerosis, Sturge-Weber syndrome, von Hippel-Lindau disease, and ataxia telangiectasia.

Ocular complications caused by malabsorption due to small intestinal bacterial overgrowth (SIBO). The main condition is nutritional deficiency optic neuropathy mediated by deficiencies of vitamins B₁₂ and B₁. Early diagnosis and treatment are important for recovery of visual function.

This article explains a vascular disease in which proximal stenosis or occlusion of the subclavian artery causes reversal of vertebral artery blood flow, leading to hypoperfusion of the vertebrobasilar system and various ocular symptoms including visual disturbances and ocular ischemia.

Ocular symptoms associated with scurvy caused by severe deficiency of vitamin C (ascorbic acid). Subconjunctival hemorrhage, retinal hemorrhage, and dry keratoconjunctivitis may occur, which improve with appropriate supplementation.

An extremely rare non-hereditary congenital neurocutaneous disease that causes arteriovenous malformations (AVMs) in the retina, brain, and orbit. It can lead to ocular complications such as vision loss and vitreous hemorrhage.

This article explains the causes, diagnosis, and treatment of abnormal head posture (ocular torticollis) that occurs as a compensatory mechanism for ocular abnormalities.

A parasitic uveitis caused by the invasion of larvae of the dog roundworm (Toxocara canis) or cat roundworm (Toxocara cati) into the eye. It primarily occurs in children and is characterized by unilateral vision loss and retinal granulomas.

Rare but serious eye injuries caused by cosmetic laser procedures such as hair removal, tattoo removal, and facial resurfacing. They can cause a variety of disorders from the anterior to the posterior segment of the eye.

This article explains the epidemiology, diagnosis, treatment, and prevention of ocular and orbital trauma caused by firearms (handguns, rifles, airsoft guns, etc.).

This article explains the epidemiology, symptoms, diagnosis, treatment, and prognosis of ocular trauma caused by flying debris (fragments) from fireworks or explosions. Blunt trauma, burns, and chemical injuries occur in combination, and severe cases can lead to globe rupture or permanent vision loss.

This article explains the initial assessment and management of ocular trauma, including triage, emergency treatment, and criteria for ophthalmology referral that non-ophthalmologists should perform.

Approaches to orbital tumor excision (anterior, lateral, transcranial, and transsinus) and surgery plans by disease. For benign tumors, complete excision without breaking the capsule is the rule. For malignant lymphoma, treatment after biopsy; for adenocarcinoma and adenoid cystic carcinoma, orbital exenteration is chosen. Radiation therapy, carbon ion therapy, and chemotherapy are combined as supportive treatment.

A rare but highly fatal intraoperative complication in which air enters the systemic venous circulation from the suprachoroidal space due to cannula dislodgement during air infusion in vitreous surgery.

The oculocardiac reflex (OCR) is a trigeminal-vagal reflex in which heart rate decreases by 20% or more due to stimulation of the extraocular muscles or eyeball. It occurs frequently during strabismus surgery and orbital trauma. This article explains its pathophysiology, diagnosis, management, and prevention.

A group of genetic disorders characterized by reduced melanin production, leading to pigment deficiency in the eyes and skin. The three main symptoms are nystagmus, photophobia, and reduced visual acuity, accompanied by foveal hypoplasia. There is no curative treatment; management focuses on refractive correction, tinted lenses, and low vision care.

A group of hereditary disorders characterized by reduced melanin production, leading to pigment deficiency in the eyes and skin. The three main symptoms are nystagmus, photophobia, and reduced visual acuity, accompanied by foveal hypoplasia. There is no curative treatment; management focuses on refractive correction, tinted lenses, and low vision care.

A benign dermal melanocytosis characterized by bluish-gray to brown pigmentation of the skin, sclera, and uvea in the distribution of the trigeminal nerve V1/V2 branches. There is a risk of glaucoma and uveal melanoma, making regular ophthalmic examinations important.

An acute dystonic reaction triggered by medications such as antipsychotics and antiemetics. Involuntary upward deviation of both eyes due to spasm and hypertonicity of the extraocular muscles, lasting from minutes to hours.

A specific neuro-ophthalmologic sign of Whipple disease (Tropheryma whipplei infection). It is characterized by slow pendular convergence-divergence nystagmus with simultaneous rhythmic contraction of the masticatory muscles, accompanied by supranuclear vertical gaze palsy.

A disorder caused by damage to the oculomotor nerve (cranial nerve III), leading to ptosis, impaired eye movement, and pupillary dilation. Main causes include aneurysm, ischemia, trauma, and tumors. If pupillary dilation is present, urgent imaging is required.

A condition in which, after injury to the oculomotor nerve (third cranial nerve), axons regenerate to the wrong muscle, causing simultaneous contraction of muscles that are normally not co-activated. It presents with ptosis, diplopia, and pupillary abnormalities, and occurs in about 15% of acquired oculomotor nerve palsy cases.

An acquired syndrome that appears late after brainstem or cerebellar lesions. It involves rhythmic movements of the soft palate and pendular nystagmus, with hypertrophic degeneration of the inferior olive as the core pathology.

Explains the mechanism of action, indications, surgical technique, comparison with mitomycin C, and outcomes of Ologen, used as an adjunct in glaucoma filtration surgery.

Explains the mechanism of action, clinical trials (AYAME, PEONY, RENGE, FUJI), side effects, and differences from conventional PGAs of omidenepag isopropyl (Eybelis®). Covers the dual intraocular pressure-lowering mechanism via EP2 receptors and the advantage of no prostaglandin-associated periorbitopathy (PAP).

A filarial infection caused by the nematode Onchocerca volvulus. Transmitted by black flies, it can cause keratitis, uveitis, and chorioretinitis, leading to blindness. It is the second leading cause of blindness due to infection worldwide.

This article explains the symptoms, diagnosis, pathological features, and treatment of benign oncocytoma (oncocytoma) arising in the ocular adnexa. It most often occurs in the caruncle, and the prognosis after complete excision is extremely good.

A horizontal eye movement disorder caused by a pontine lesion. It combines ipsilateral horizontal gaze palsy ("1") with ipsilateral internuclear ophthalmoplegia ("0.5"), resulting in a characteristic syndrome where only abduction of the contralateral eye is preserved.

This article explains the types of anesthesia used in ophthalmic surgery (such as topical anesthesia, sub-Tenon's anesthesia, retrobulbar anesthesia, and general anesthesia), the drugs used, complications, and the latest trends.

A rare vascular lesion in which a false lumen forms in the ophthalmic artery due to trauma or postoperative complications. It is characterized by a pulsatile orbital mass, and endovascular coil embolization is the first-line treatment.

Representative ophthalmic complications of corticosteroid administration include posterior subcapsular cataract and steroid-induced glaucoma. There is a risk of development regardless of route, dose, or duration of administration, and regular ophthalmic monitoring is necessary.

Ophthalmic delusional parasitosis is a rare psychiatric disorder characterized by a fixed false belief that the eyes are infested with parasites. This article explains its diagnosis, differential diagnosis, and treatment.

Explains emergency symptoms that require immediate ophthalmology consultation, such as sudden vision loss, severe eye pain, or chemical exposure, categorized by urgency. Describes first aid and where to seek care for conditions like central retinal artery occlusion, acute angle-closure glaucoma attack, retinal detachment, chemical injury, and orbital cellulitis.

This article explains the characteristics of visual impairment caused by craniopharyngioma, the mechanism of optic chiasm compression, and diagnosis and treatment.

Ocular complications associated with tick-borne viral hemorrhagic fever caused by Kyasanur Forest disease virus (KFDV). Ocular findings may include conjunctival injection, retinal hemorrhage, vitreous hemorrhage, and papilledema.

This article describes the epidemiology, symptoms, diagnosis, treatment, and pathophysiology of ophthalmic and neuro-ophthalmic complications associated with Nipah virus infection, including cranial nerve palsy, Horner syndrome, and branch retinal artery occlusion.

Explanation of ocular complications caused by Rift Valley fever virus (RVFV). Posterior segment lesions, primarily macular retinitis, are characteristic, with ocular symptoms occurring in 0.5–15% of infected individuals, and severe cases leading to permanent vision loss.

Neuro-ophthalmic signs appearing in hereditary prion disease, fatal familial insomnia (FFI), caused by the D178N mutation in the PRNP gene. Saccadic intrusions and fluctuating diplopia present as early symptoms, reflecting selective thalamic degeneration.

This article explains the pathophysiology, diagnosis, and treatment of ophthalmic signs associated with Chiari malformation, including nystagmus, optic disc edema, cranial nerve palsy, and strabismus.

Creutzfeldt-Jakob disease (CJD) is a rare prion disease, and the Heidenhain variant (HVCJD) may present with visual symptoms as the initial manifestation. This article discusses the ophthalmic signs, diagnosis, and management of CJD.

This article explains the various ocular symptoms that occur with epileptic seizures. It provides an overview of ophthalmic signs such as visual hallucinations, visual field defects, eye deviation, and nystagmus, which vary depending on the location of the epileptic focus.

This article explains the pathophysiology, diagnosis, and management of ophthalmic diseases associated with obstructive sleep apnea (OSA), including floppy eyelid syndrome, glaucoma, NAION, papilledema, keratoconus, and central serous chorioretinopathy.

Spinocerebellar ataxia (SCA) is a group of hereditary neurodegenerative disorders that present with various ophthalmic signs such as nystagmus, ophthalmoplegia, and retinal degeneration. Ophthalmic findings differ depending on the type of SCA, and ophthalmologic evaluation plays an important role in diagnosis and management.

A comprehensive explanation of various staining agents used in ophthalmology, including fluorescein, lissamine green, rose bengal, trypan blue, and ICG, covering their types, principles, clinical applications, and side effects.

This article explains the principles, techniques, indications, and interpretation of A-mode, B-mode, and UBM (ultrasound biomicroscopy) used in ophthalmology. It is an essential imaging diagnostic method for evaluating intraocular lesions and when the ocular media are opaque.

Ophthalmic viscosurgical devices (OVDs) are surgical aids used in intraocular surgeries such as cataract surgery. They are essential surgical instruments that play various roles, including maintaining anterior chamber space, protecting corneal endothelium, separating tissues, and assisting IOL insertion.

This article explains the various ophthalmological abnormalities associated with lissencephaly (a disorder of neuronal migration in the brain), categorized by type 1 (classic) and type 2 (cobblestone) lissencephaly.

A disease in which fly larvae (maggots) infest the eye. It is classified into external and internal types, with Oestrus ovis (sheep botfly) being the most common causative species. It is more common in rural areas and among livestock workers, but also occurs in urban areas.

A rare autoimmune neurological syndrome characterized by multidirectional involuntary eye movements without saccadic intervals (opsoclonus), myoclonus, and cerebellar ataxia. It is primarily paraneoplastic or post-infectious in etiology, and immunomodulatory therapy is the mainstay of treatment.

A type of optic neuritis involving inflammation of the optic chiasm. Characterized by bitemporal hemianopia, it can be caused by various conditions such as multiple sclerosis, NMO, MOGAD, infections, and autoimmune diseases. Steroid pulse therapy is the first-line treatment.

A congenital condition characterized by a depression or defect in the optic disc due to incomplete closure of the posterior part of the embryonic fissure (optic cup fissure). Visual acuity depends on the degree of involvement of the papillomacular bundle. It can be complicated by serous retinal detachment or rhegmatogenous retinal detachment. It is important to screen for systemic associations such as CHARGE syndrome and renal coloboma syndrome.

Calcified deposits within the optic nerve head. There are superficial and buried types; buried type requires differentiation from papilledema. Prevalence is 0.41–2.0%, usually asymptomatic, but visual field abnormalities are found in over 70% of cases, requiring management as a chronic progressive optic nerve disease.

Definition, epidemiology, mechanical and vascular hypotheses, association with glaucoma, diagnosis, and prognosis of optic disc hemorrhage (Drance hemorrhage). Based on evidence from major trials such as OHTS, CNTGS, and EMGT.

A benign tumor with heavy pigmentation arising from the optic disc. Most cases are asymptomatic, but visual symptoms may occur due to vascular occlusion or necrosis. OCT-A microvascular assessment is useful for differential diagnosis.

A congenital depression (pit) in the optic disc that is associated with serous macular detachment (optic disc pit maculopathy) in 25–75% of cases, leading to vision loss.

This article explains the definition, imaging diagnosis, chemotherapy (carboplatin + vincristine), association with NF1, and prognosis of optic pathway glioma.

A rare severe injury in which the optic nerve is separated from the eye at the level of the lamina cribrosa due to trauma. Complete avulsion results in no light perception, and there is no established effective treatment. Early diagnosis and avoidance of unnecessary treatment are important.

This article provides an overview, diagnosis, and treatment of congenital optic disc excavation anomalies, including optic disc coloboma, morning glory syndrome, peripapillary staphyloma, and optic disc pit.

Optic nerve head avulsion (optic nerve head avulsion) is a rare condition in which trauma separates the optic nerve from the eyeball at the level of the lamina cribrosa. It causes severe visual impairment, and there is no established treatment.

Definition and classification (superficial and buried types) of optic nerve head drusen (ONHD), differentiation from pseudopapilledema, diagnostic methods (ultrasound, OCT, autofluorescence), visual field defects, and association with glaucoma.

Optic nerve hypoplasia (ONH) is the most common congenital optic nerve anomaly, characterized by a reduced number of optic nerve axons. This article explains its association with septo-optic dysplasia (SOD), diagnostic imaging, endocrine screening, and multidisciplinary management.

A surgical procedure that creates a window in the optic nerve sheath to drain cerebrospinal fluid, preventing vision loss due to elevated intracranial pressure. Idiopathic intracranial hypertension (IIH) is the most common indication.

A benign tumor arising from the meninges of the optic nerve, characterized by slowly progressive unilateral vision loss. MRI shows a characteristic tram-track sign, and the first-line treatment is radiotherapy.

This article explains the definition, imaging diagnosis (tram-track sign), and management including stereotactic radiotherapy of optic nerve sheath meningioma (ONSM).

Optic neuritis associated with multiple sclerosis (MS) is characterized by acute unilateral painful vision loss and may be the initial symptom of MS. Diagnosis is made using MRI and cerebrospinal fluid analysis based on the McDonald criteria, and management includes steroid pulse therapy and disease-modifying therapies. Differentiation from MOGAD and NMOSD is important.

An inflammatory and demyelinating disease of the optic nerve that occurs or relapses during pregnancy or postpartum. The incidence increases after delivery due to immune rebound, with acute vision loss and eye movement pain as main symptoms.

A hub article for differentiating optic neuropathies based on acute/chronic, unilateral/bilateral, presence of pain, and optic disc findings. Includes GCA emergency response flow, interpretation of RAPD/OCT/visual fields, and cause-specific one-liners.

Optic neuropathy occurring after SARS-CoV-2 infection. Two types have been reported: ischemic optic neuropathy (ION) and optic neuritis (ON). Inflammation, hypercoagulability, and autoimmune reactions are involved in its pathogenesis.

Optic neuropathy occurring as an immune-related adverse event of immune checkpoint inhibitors (ICIs) used in immunotherapy for malignant tumors. Steroid treatment and decisions regarding continuation or discontinuation of ICIs are important.

Optic neuropathy caused by fibrous dysplasia of the skull compressing the optic canal in McCune-Albright syndrome (MAS). Early diagnosis and appropriate timing of surgical intervention determine visual prognosis.

An orbital inflammatory disease in which inflammation is confined to the optic nerve sheath. It presents with eye pain and various visual symptoms. MRI findings of tram-track sign and doughnut sign are key to diagnosis. It responds rapidly to steroid therapy, but caution is needed for recurrence during dose reduction.

Explains the principle of optical biometry, SS-OCT devices (IOLMaster 700, ARGOS), measurement parameters, comparison with ultrasound, and application to IOL power calculation. It is an essential test before cataract surgery and is also used for myopia progression monitoring.

A non-invasive imaging technique that captures cross-sectional images of the retina. It is an essential tool for diagnosing and monitoring many eye diseases such as macular diseases, diabetic retinopathy, and glaucoma.

An imaging diagnostic technique that uses the interference phenomenon of near-infrared light to non-invasively obtain cross-sectional images of the retina and optic nerve. It is essential for diagnosis and follow-up in a wide range of conditions including macular diseases, diabetic retinopathy, glaucoma, and neuro-ophthalmic disorders. This article comprehensively explains imaging modes, normal layer structure, representative findings, glaucoma analysis, and neuro-ophthalmic applications.

Optical coherence tomography (OCT) is a non-invasive imaging technique that provides high-resolution cross-sectional images of the retina and optic nerve. It is widely used for diagnosis and monitoring of neuro-ophthalmic diseases such as optic neuritis, multiple sclerosis, and compressive optic neuropathy.

A non-invasive imaging diagnostic technique that three-dimensionally visualizes retinal and choroidal vascular structures without the need for contrast agents. It comprehensively explains the principles, procedures, findings, and clinical applications of vascular assessment in diabetic retinopathy, age-related macular degeneration, retinal vein occlusion, and glaucoma.

A non-invasive fundus angiography technique that three-dimensionally visualizes retinal and choroidal vascular networks without the use of contrast agents. It is widely applied in the diagnosis and follow-up of diabetic retinopathy, age-related macular degeneration, retinal vein occlusion, and other conditions.

Collateral vessels on the optic disc connecting the retinal and choroidal circulations. They form in association with CRVO or optic nerve sheath meningioma and do not require treatment themselves, but are an important finding for diagnosing the underlying disease.

Explains the anatomical structure of the ora serrata, its association with ora serrata tears and peripheral retinal detachment, and its importance in vitreous surgery.

A syndrome presenting with optic neuropathy and multiple cranial nerve palsies due to lesions at the orbital apex. Etiologies include inflammatory, infectious, and neoplastic causes. Early diagnosis and treatment based on the underlying cause are important.

Orbital blowout fracture is a condition in which the orbital floor or medial wall is fractured due to blunt trauma to the eye, with main symptoms of diplopia, enophthalmos, and restricted eye movement. In closed fractures with entrapment of extraocular muscles, emergency surgery within 24 hours is required.

This article explains the definition, imaging diagnosis, and surgical treatment of cavernous hemangioma, a representative benign orbital tumor in adults. It is an encapsulated vascular mass commonly found within the muscle cone, with characteristic delayed enhancement on dynamic MRI. The standard surgical procedure is complete en bloc excision via a lateral orbitotomy, and the prognosis after complete resection is favorable.

An infection of the soft tissues within the orbit posterior to the orbital septum. Most commonly spreads from sinusitis and frequently occurs in children. It presents with proptosis, ophthalmoplegia, and vision loss, requiring prompt antibiotic therapy and, if necessary, surgical drainage.

An infection of the soft tissues within the orbit posterior to the orbital septum. Most commonly spreads from sinusitis and frequently occurs in children. It presents with proptosis, ophthalmoplegia, and vision loss, requiring prompt antibiotic therapy and, if necessary, surgical drainage.

An orbital dermoid cyst (dermoid cyst) is a congenital choristoma that develops along a bony suture because embryonic ectoderm becomes trapped. It accounts for 46% of pediatric orbital neoplasms and most often occurs just outside the eyebrow. Imaging with CT/MRI and complete removal without rupturing the cyst wall are key to treatment.

An ophthalmic emergency in which a rapid increase in intraorbital pressure compromises blood flow to the optic nerve and retina, leading to irreversible blindness if urgent decompression is not performed. Immediate decompression via lateral canthotomy and inferior cantholysis is the mainstay of treatment.

Orbital decompression is a surgery that removes orbital walls to expand orbital volume for proptosis and compressive optic neuropathy associated with thyroid eye disease. Techniques range from 1-wall to 3-wall plus fat decompression, with greater reduction in proptosis as the number of walls increases. During the inflammatory phase, steroid pulse therapy is prioritized; decompression is performed in cases unresponsive to medication or in emergencies.

Orbital dermolipoma is a type of congenital choristoma containing adipose tissue, typically a benign mass occurring in the subconjunctival space of the superotemporal quadrant. This article explains its diagnosis, treatment, and associated syndromes.

A condition caused by abnormal accumulation of air within the orbit. The most common cause is nose blowing after an orbital wall fracture. In most cases, it resolves spontaneously within 7–10 days, but severe cases can lead to orbital compartment syndrome and potential blindness.

An orbital floor fracture (blowout fracture) is a fracture caused by blunt trauma to the eye area, with double vision, sunken eye, and impaired eye movement as the main symptoms. Treatment ranges from urgent surgery to observation depending on whether tissue is trapped and on the fracture type.

A fracture of the orbital floor caused by blunt trauma to the eye, with main symptoms of diplopia, enophthalmos, and impaired eye movement. Closed fractures with entrapment of extraocular muscles are common in children and require emergency surgery. Surgery reconstructs the orbital floor using titanium mesh or absorbable plates.

This article explains the definition, classification, diagnosis, treatment, and prognosis of orbital foreign bodies, including imaging diagnosis centered on CT and management strategies based on material type.

Orbital fracture repair is a surgery to reduce incarcerated tissue and reconstruct the bony wall for fractures of the orbital floor and medial wall caused by blunt ocular trauma. Closed (trapdoor) fractures are common in children and require emergency surgery due to extraocular muscle entrapment. Selection of reconstruction materials such as titanium mesh, absorbable plates, and autologous bone is important.

A rare benign soft tissue tumor in the orbit that arises from Schwann cells. It often develops in the extraocular muscles, especially the inferior rectus, and can cause proptosis and diplopia. Complete removal is the first-choice treatment.

A vascular malformation of the orbit (lymphatic malformation) that is common in childhood. It can present suddenly with eye bulging and eye pain because of bleeding within the mass (chocolate cyst). On MRI, a multilocular mass with fluid-fluid levels is a diagnostic finding. Conservative observation is the basic approach, but in severe cases, debulking surgery and sclerotherapy may be considered. The rebleeding rate is about 70%, so long-term follow-up is necessary.

This article explains the pathology, diagnosis, and treatment of lymphoma occurring in the orbit. It covers the characteristics and treatment strategies for each histological type, from the most common MALT lymphoma to high-grade DLBCL.

Orbital melanoma is a malignant tumor derived from melanocytes that occurs within the orbit. It is classified into primary and secondary types. Primary orbital melanoma is extremely rare, accounting for less than 1% of all orbital tumors. Standard treatment involves surgery and adjuvant radiation therapy.

A rapidly progressive, fatal fungal infection caused by Mucorales fungi that spreads from the paranasal sinuses to the orbit and brain. It commonly occurs in patients with diabetes or immunodeficiency, and without treatment, the mortality rate reaches 79%. The mainstay of treatment is a combination of liposomal amphotericin B antifungal therapy and surgical debridement.

Orbital rhabdomyosarcoma is the most common orbital malignant tumor in children. It is characterized by rapidly progressive proptosis. Standard treatment is a combination of surgery, chemotherapy (VAC regimen), and radiation therapy (proton beam therapy has been covered by insurance since 2016). The 5-year survival rate for primary orbital cases is over 90%.

Orbital roof fracture is a relatively rare orbital fracture caused by trauma to the forehead. In adults, it is often associated with high-energy trauma and severe head injury. Multidisciplinary collaboration with neurosurgery and otolaryngology is necessary.

Orbital schwannoma is a rare benign tumor derived from Schwann cells, accounting for 1-2% of all orbital tumors. The main symptom is slowly progressive proptosis, and complete surgical excision is the standard treatment.

A comprehensive overview of the classification, symptoms, diagnosis, and treatment of orbital masses. It covers a wide range of etiologies from benign lymphoproliferative disorders to life-threatening malignant tumors, and describes a diagnostic approach centered on imaging and pathological examination.

An orthoptist (ORT) is a nationally licensed medical professional who performs orthoptic training for binocular vision and ophthalmic examinations under the direction of a physician. This article explains their scope of practice, legal status, education system, and work settings.

Outer retinal tubulation (ORT) is a form of photoreceptor reorganization that occurs in chronic degenerative retinal diseases. This article explains the characteristic OCT findings, differential diagnosis, and clinical significance.

A review of glaucoma eye drops by drug class, covering mechanisms of action, intraocular pressure-lowering effects, and side effects. Includes prostaglandin analogs, beta-blockers, alpha agonists, carbonic anhydrase inhibitors, ROCK inhibitors, miotics, and combination drugs.

This article explains the mechanism of action, clinical trials, administration, and real-world clinical data of Oxervate (cenegermin-bkbj 0.002%), the first FDA-approved treatment for neurotrophic keratitis (NK).

Oxidative stress, an imbalance between reactive oxygen species (ROS) and antioxidant defense systems, is a central pathological mechanism involved in the onset and progression of over 100 ophthalmic diseases, including glaucoma, age-related macular degeneration, diabetic retinopathy, cataracts, and retinitis pigmentosa.

This article explains the mechanism of action, dosage, clinical trials, and side effects of oxymetazoline 0.1% ophthalmic solution (Upneeq), the first FDA-approved drug for acquired blepharoptosis.