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Macular corneal dystrophy (MCD) is an autosomal recessive corneal dystrophy caused by mutations in the CHST6 gene, leading to diffuse accumulation of glycosaminoglycans (keratan sulfate) in the corneal stroma. Bilateral vision loss occurs from around 10 to 30 years of age. Treatment includes deep anterior lamellar keratoplasty (DALK) or penetrating keratoplasty (PKP).

A macular hole (MH) is a full-thickness defect of the retina at the fovea, causing decreased central vision and metamorphopsia. With vitrectomy, internal limiting membrane peeling, and gas tamponade, 91–98% of cases achieve closure, and visual improvement persists for up to 3 years postoperatively.

Explains the principles, measurement parameters (GCC, GCIPL), diagnostic ability, progression detection, floor effect limitations, and OCTA prospects of macular OCT (optical coherence tomography) in glaucoma diagnosis. Includes the importance of comprehensive evaluation by combining with RNFL analysis.

A rare secondary angle-closure glaucoma in which aqueous humor is misdirected posteriorly, causing forward displacement of the iris-lens diaphragm, angle closure, and elevated intraocular pressure. It often occurs after filtration surgery.

A malignant tumor arising from melanocytes in the eyelid skin. It is rare, accounting for less than 1% of all cutaneous melanomas, but pigmented lesions with a diameter of 7 mm or more require referral to a specialist. Prognosis depends largely on tumor thickness and stage.

An autosomal dominant connective tissue disorder caused by mutations in the FBN1 gene. Ocular manifestations frequently include ectopia lentis, with increased risk of glaucoma, cataract, and retinal detachment.

A recurrent inflammatory disease characterized by sterile infiltration and ulceration in the peripheral cornea due to a type III allergic reaction to antigens of staphylococci that normally reside on the eyelids. It is frequently associated with blepharitis.

Explanation of symptoms, diagnosis, and treatment for fractures of the medial orbital wall (lamina papyracea of the ethmoid bone). The medial wall, being the thinnest of the orbital walls, is prone to fracture from blunt trauma, causing diplopia and enophthalmos.

This article explains the medical expense subsidy system for designated intractable diseases in the field of ophthalmology, including target diseases, application procedures, maximum out-of-pocket amounts, and renewal of the recipient certificate.

This article explains a rare intraocular tumor arising from the nonpigmented ciliary epithelium, including its clinical features in children, differentiation from retinoblastoma, and treatment strategies.

An autosomal dominant corneal dystrophy characterized by multiple microcysts within the corneal epithelium due to mutations in the KRT3 or KRT12 genes. Onset occurs early in life, but symptoms are usually mild and may include recurrent corneal erosions.

A chronic, diffuse abnormality of the meibomian glands characterized by terminal duct obstruction and/or qualitative or quantitative changes in gland secretion. It is the most common cause of evaporative dry eye, affecting 10–30% of people aged 50 years or older in Japan.

A general term for conjunctivitis in which a membrane composed of fibrin and inflammatory exudate forms on the conjunctival surface. True membranes embed into the conjunctival epithelium and bleed upon removal, whereas pseudomembranes adhere to the surface and can be easily removed. Adenoviral conjunctivitis is the most common cause.

A rare and highly malignant neuroendocrine tumor derived from Merkel cells. It commonly occurs in the head and neck region, with 5–10% arising on the eyelid. It grows rapidly and tends to metastasize via the lymphatic system.

Metabolic syndrome (visceral obesity + hyperglycemia, hypertension, dyslipidemia) increases the risk of various eye diseases such as diabetic retinopathy, age-related macular degeneration, retinal vein occlusion, glaucoma, and central serous chorioretinopathy. Improving lifestyle habits also contributes to better ophthalmic prognosis.

A rare condition in which systemic malignant tumors metastasize hematogenously to the extraocular muscles. Primary tumors include breast cancer, lung cancer, and cutaneous melanoma, causing restricted eye movement and diplopia. Prognosis is poor, and treatment is mainly palliative.

A condition in which systemic malignant tumors, such as lung cancer and breast cancer, metastasize hematogenously to the choroid. It is characterized by yellowish-white flat lesions and marked serous retinal detachment, with radiation therapy and systemic chemotherapy being the main treatment options.

The most widely used immunomodulatory drug for non-infectious uveitis. It is an antimetabolite with antifolate activity, used globally as a first-line steroid-sparing agent.

Microspherophakia is a congenital malformation characterized by a decreased equatorial diameter and increased anteroposterior diameter of the lens. Lenticonus is a congenital anomaly in which a conical protrusion occurs on the anterior or posterior surface of the lens. Both are caused by abnormalities of the zonules or lens capsule development and are often complicated by secondary glaucoma, high myopia, and cataracts.

Microsporidia are obligate intracellular spore-forming fungi that cause ocular infections presenting as two clinical forms: keratoconjunctivitis and stromal keratitis. They affect not only immunocompromised individuals but also immunocompetent individuals, and are often misdiagnosed as herpetic keratitis. Special staining of corneal scrapings and confocal microscopy are useful for diagnosis.

Moebius syndrome is a rare congenital disorder characterized by horizontal gaze palsy and facial paralysis due to congenital dysfunction of the sixth and seventh cranial nerves. It is classified under congenital cranial dysinnervation disorders (CCDDs).

A central nervous system demyelinating disease caused by autoantibodies against myelin oligodendrocyte glycoprotein (MOG). Its main phenotypes are optic neuritis, ADEM, and myelitis. It is a disease concept independent of MS and AQP4-positive NMOSD. International diagnostic criteria were established in 2023.

An eye movement disorder in which one eye is limited in upward gaze in both adduction and abduction. It is often congenital and presents with hypotropia, ptosis, and abnormal head posture.

Explains the types, materials, optical designs, power calculation, surgical outcomes, and postoperative complications of monofocal intraocular lenses (IOLs), which are most commonly used in cataract surgery. Hydrophobic acrylic is the standard material, and there are various options such as aspheric design and toric design.

Monovision is a method to compensate for presbyopia by correcting one eye for distance and the other for near vision. This article details its application with contact lenses, LASIK, and cataract IOLs, dominant eye setting, effects on stereopsis, and the trial wear procedure.

Mooren's ulcer (rodent corneal ulcer) is an idiopathic autoimmune peripheral corneal ulcer that progresses along the corneal limbus. It is characterized by an arcuate ulcer with undermined edges, and the sclera is not involved. An autoimmune reaction against calgranulin C in the corneal stroma is thought to be involved in the pathogenesis.

A congenital optic disc anomaly characterized by funnel-shaped excavation of the optic disc, white glial tissue, and radial blood vessels. It is frequently associated with retinal detachment and is known to be related to transsphenoidal encephalocele.

A chronic bilateral disease presenting with multiple inflammatory lesions at the level of the retinal pigment epithelium and choriocapillaris. It is distinguished from punctate inner choroidopathy by the presence of anterior chamber and vitreous inflammation.

Multifocal (bifocal/progressive) contact lenses are contact lenses designed primarily for presbyopia correction, integrating multiple focal points for distance and near vision into a single lens. This article explains the differences in design (concentric, EDOF, HCL), actual prescription procedures, selection of candidates, and management of complications.

A comprehensive explanation of multifocal intraocular lenses (trifocal, EDOF, accommodating IOL) in cataract surgery, including classification, optical principles, selection criteria, visual outcomes, complication management, and mix-and-match strategies.

An acute inflammatory disease typically affecting one eye in young myopic women. Transient dysfunction of the outer retina and ellipsoid zone leads to gray-white spots that resolve spontaneously within weeks.

Multiple sclerosis (MS) is an immune-mediated demyelinating disease of the central nervous system that presents with various ocular symptoms such as optic neuritis and internuclear ophthalmoplegia. Diagnosis is based on the McDonald criteria, including MRI and cerebrospinal fluid analysis, and management involves steroid pulse therapy and disease-modifying therapies.

An antimetabolite immunosuppressant used for non-infectious uveitis. It selectively inhibits IMPDH to suppress lymphocyte proliferation and is positioned as a steroid-sparing agent with a favorable side effect profile.

Myopia is a refractive error in which the refractive power is excessive relative to the axial length, resulting in decreased distance vision. This article provides a comprehensive explanation from simple myopia to pathological myopia, including the latest evidence for myopia progression control treatment including low-concentration atropine eye drops (Rijusea® Mini 0.025%).

Childhood myopia is a refractive error that develops during school age, primarily caused by axial elongation. Multiple progression control therapies, including low-dose atropine eye drops, myopia management spectacles, multifocal contact lenses, and orthokeratology, have accumulated evidence.

Orthokeratology (OK) is a treatment that uses specially designed hard contact lenses worn overnight to reshape the cornea, restoring uncorrected visual acuity and slowing myopia progression in children. This article explains indications, prescribing procedures, safety management, and combination with low-concentration atropine.

Choroidal neovascularization (MNV) that occurs in the fundus of pathologic myopia. It occurs in 5–11% of high myopia eyes and is the leading cause of MNV in individuals aged 50 years or younger. Intravitreal injection of anti-VEGF drugs is the first-line treatment.