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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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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

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.

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 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.

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.

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.

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

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.

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.

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.

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.

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.

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 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.

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.

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.

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.

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.

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.

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.