Pathologic myopia (PM) is defined as high myopia with a refractive error of -6.0 D or more or an axial length of 26.5 mm or more, accompanied by degenerative fundus changes. According to the META-PM (Meta-Analysis for Pathologic Myopia) classification, eyes with diffuse atrophy or more severe atrophic changes in the fundus, or with posterior staphyloma, are diagnosed as pathologic myopia.
Pathologic myopia accounts for 13% of visual impairment with corrected visual acuity of 0.1 or less, and is the second leading cause of blindness after glaucoma. The global prevalence is reported to be 0.2–3.8%, with particularly high prevalence in East Asia.
Myopic maculopathy is a general term for posterior pole fundus lesions including myopic chorioretinal atrophic lesions and three independent lesions (plus lesions). Plus lesions consist of lacquer cracks, myopic MNV (myopic neovascularization; formerly called choroidal neovascularization/CNV), and Fuchs spot. The term MNV is internationally transitioning from CNV. 1)
The ATN classification is also used to describe fundus lesions. A stands for Atrophy (atrophic changes), T for Tractional (tractional changes), and N for Neovascular (myopic MNV). Combining the META-PM and ATN classifications allows comprehensive evaluation of the type, severity, and activity of lesions. 5)
Staphyloma is a localized bulging of the sclera due to axial elongation and is an important finding characterizing pathologic myopia. Age, axial length, and posterior pole morphology are emphasized in assessing the onset and progression of pathologic myopia. 7)
Myopic MNV occurs in 5–11% of highly myopic eyes and is the leading cause of CNV in individuals aged 50 years or younger. Over an 8-year follow-up, approximately 6% of pathologic myopia patients without a history of MNV develop it, and in cases with unilateral history, about 35% develop it in the fellow eye.
Myopic traction maculopathy (MTM) is observed in 9–34% of highly myopic eyes with posterior scleral staphyloma. It was first described by Phillips in 1958 as “posterior pole retinal detachment without macular hole in high myopia.” In 1999, Takano and Kishi reported its detection by OCT, and Panozzo proposed the term “MTM.”
The following risk increases per 1 D increase in myopia highlight the importance of slowing progression. 8)
| Complication | Risk increase per 1 D increase |
|---|---|
| Macular degeneration | 58% increase |
| Open-angle glaucoma | 20% increase |
| Cataract | 21% increase |
| Retinal detachment | 30% increase |
High myopia refers to a refractive error of -6D or more, or an axial length of 26.5 mm or more. Pathologic myopia additionally involves degenerative fundus changes (such as atrophy, staphyloma, lacquer cracks, etc.) and is defined by the META-PM classification as “eyes with diffuse atrophy or more severe atrophic changes, or posterior staphyloma.” Pathologic myopia has a poor visual prognosis and leads to serious complications such as MNV and MTM.
The main fundus findings based on the META-PM classification are shown below.
Early to Intermediate Stage
Tessellated fundus: Typical finding where choroidal vessels are visible. Corresponds to Category 1–2.
Peripapillary atrophy (PPA): Thinning of the choroid and RPE around the optic disc. Present from early stages.
Lacquer cracks: Linear breaks in Bruch’s membrane. Odds ratio for CNV development: 2.56. 6)
Advanced Stage
Diffuse atrophy: Widespread thinning and atrophy of the RPE and choroid. Progresses in 57% over the long term. 6)
Focal atrophy / Macular atrophy: Well-defined yellowish patchy atrophic lesions. Bruch’s membrane disappears in a planar fashion, and the choriocapillaris is completely occluded. 81% of focal atrophy progresses, and if it involves the fovea, severe visual impairment occurs. 6)
Staphyloma: Bulging of the sclera at the posterior pole. Confirm morphology with fundus photography and OCT.
Stage-specific findings of myopic MNV (Plus lesion):
OCT findings and staging of myopic traction maculopathy (MTM):
OCT shows inner retinal layer separation and bridging structures across the retinal gap. Severity is graded from S0 to S4. 20)
| Stage | Extent of separation | Characteristics |
|---|---|---|
| S0 | None | No separation |
| S1 | Only extrafoveal | Parafoveal separation |
| S2 | Involving fovea | Foveal separation present |
| S3 | Involving fovea but not entire macula | Partial macular separation |
| S4 | Entire macula | Most likely to progress, requires greatest caution |
Some cases present with multiple perifoveal retinal detachments; attention should be paid to the coexistence of shallow foveal detachment, lamellar/full-thickness macular hole, and epiretinal membrane. 18)
Unlike age-related macular degeneration, myopic MNV can develop from the teenage years. It is the most common cause of CNV in individuals aged 50 years or younger, and early onset is characteristic. After onset in one eye, the fellow eye also develops MNV in about 35% of cases, so regular bilateral eye examinations are important.
Axial elongation is the fundamental cause of pathologic myopia. As the axial length increases, the retina, choroid, and sclera are stretched, leading to thinning, atrophy, and cracks. Axial elongation continues even in adults, progressing at about 0.1 mm per year between ages 18 and 25, and about 0.05 mm per year after age 25. 15)
In the Hisayama Study (reported in 2012, targeting residents aged 40 years or older), the prevalence of diffuse atrophy was 1.7%, and that of patchy atrophy and macular atrophy was 0.4% each. The odds ratio was 3.29 for women, 1.12 per year of age, and 4.20 per 1 mm increase in axial length.
MNV risk factors:
MTM risk factors:
Risk factors for progression of myopic maculopathy: Peripapillary diffuse atrophy, female sex, rapid axial elongation, long axial length, and older age, in descending order of odds ratio. Progression rate is 47.0 per 1,000 eye-years (follow-up over 10 years). Type IX (septal) staphyloma shows a progression rate of 86% (OR 29.3). 6)
Each 1 diopter increase in myopia significantly increases the risk of macular degeneration, glaucoma, cataract, and retinal detachment. 8) The number needed to treat (NNT) for myopia progression control is estimated at 4.1–6.8, indicating that slowing progression directly prevents future complications. 8)
The META-PM classification and ATN classification are combined to systematically evaluate the type, severity, and activity of the lesion. 1, 5) The presence of staphyloma is an important diagnostic indicator with a positive predictive value of 89.8% for pathologic myopia. 7)
| Differential Disease | Key Points for Differentiation |
|---|---|
| Simple Macular Hemorrhage | No fluorescein leakage on FA. Spontaneous absorption in 2–3 months. OCT shows hyperreflectivity along the Henle fiber layer. |
| Age-Related Macular Degeneration | Accompanied by drusen and RPE detachment. Exudative changes are prominent. |
| Punctate inner choroidopathy (PIC) | Young women with moderate myopia. Small yellowish-white lesions (≤500 μm) confined to the posterior pole. Choroidal thickening associated with inflammation. |
| Multifocal choroiditis (MFC) | Related disease to PIC. Choroidal inflammation is involved. |
| Dome-shaped macula | Characteristic inward convex protrusion on OCT. May be associated with MNV. |
| Tilted disc syndrome | MNV can occur at the edge of inferior staphyloma. |
Simple macular hemorrhage is bleeding due to choroidal capillary damage during lacquer crack formation, often resolving spontaneously within 2–3 months without treatment. Myopic MNV is bleeding associated with MNV (neovascularization) and shows fluorescein leakage on FA. If differentiation by OCT alone is difficult, FA examination is essential. 1)
Currently, there is no effective treatment for myopic chorioretinal atrophic lesions (diffuse atrophy, patchy atrophy, macular atrophy). Regular follow-up with OCT, fundus examination, and FAF is the standard.
Intravitreal injection of anti-VEGF drugs is the first-line treatment, with efficacy proven in multicenter prospective RCTs. 1)
Approved drugs (Japan):
Dosing regimen: One initial injection followed by additional injections as needed (1+PRN) is the standard regimen. 1, 2, 5)
Key RCTs:
Follow-up: Monthly follow-up for active MNV. After MNV stabilization, the injection interval can be extended up to 3 months. 5) Early detection and treatment are important to intervene before MNV enlargement or scar formation. 1)
Other treatments:
Vitrectomy is the basic treatment.
Vitrectomy
Pars plana vitrectomy (PPV) with internal limiting membrane peeling: Releases anterior traction and removes the scaffold for cell proliferation.
Inverted ILM flap technique: Compared to ILM peeling alone, it has higher retinal reattachment rate (97.8% vs 82%) and macular hole closure rate (93.5% vs 38.5%). 17)
Fovea-sparing internal limiting membrane peeling: A technique to reduce the risk of iatrogenic macular hole. 20)
Macular Buckle
Macular buckle surgery: A procedure in which scleral buckle material is placed at the posterior pole to push up the staphyloma from the outside. It directly addresses the structural cause of staphyloma.
Advantages: Avoidance of cataract formation and iatrogenic macular hole. Higher anatomical success rate and better functional outcomes have been reported compared to vitrectomy alone. 17)
Precautions: Attention should be paid to vortex vein compression, traumatic optic neuropathy, and hyperopic shift.
Surgical indications: Cases with visual impairment, concern for progression to macular hole or tractional retinal detachment, or progression of foveal detachment. 20)
Surgical prognosis:
The standard regimen for anti-VEGF for myopic MNV is one injection plus pro re nata (1+PRN). 1) The average number of injections is 1.8 over 12 months, which tends to be fewer than for age-related macular degeneration. 9) However, long-term follow-up for recurrence and enlargement of atrophy is essential, and early retreatment is recommended.
As axial elongation progresses, the sclera at the posterior pole becomes thin and stretched, forming a localized bulge (staphyloma). The formation of staphyloma increases physical tension on the retina, choroid, and RPE.
Axial elongation → choroidal atrophy → reduction of elastic fibers in Bruch’s membrane → mechanical rupture of Bruch’s membrane (lacquer cracks). When lacquer cracks form, the choriocapillaris is also damaged, often accompanied by simple macular hemorrhage.
The fissures caused by lacquer cracks serve as a scaffold for connective tissue associated with MNV to proliferate beneath the RPE or subretinally. In addition to the wound healing response using mechanical breaks as a scaffold, circulatory disturbances due to loss of the choriocapillaris and choroidal vessels are thought to promote VEGF production, leading to the formation of abnormal vascular networks.
As the source vessels for myopic MNV, short posterior ciliary arteries penetrating the sclera near the myopic MNV were confirmed in 75.0% of cases, with perfusion observed in 100% of active, 87.9% of scar, and 73.8% of atrophic stages.
In a long-term follow-up study of 1228 European eyes (mean 11.5 years), 57% of diffuse atrophy and 81% of focal atrophy progressed during follow-up. 6) In the untreated natural course of myopic MNV, 89% at 5 years and 96% at 10 years had decimal visual acuity of 0.1 or worse.
The pathogenesis of MTM is multifactorial, involving three main traction mechanisms.
Müller cell dysfunction (impaired regulation of intracellular fluid and metabolic water) leads to increased fluid inflow, contributing to cavity formation. 19) Additionally, choroidal perfusion impairment reduces retinal adhesion to the RPE, making detachment more likely even with minimal traction. 18)
The combination of MTM and MNV is rare but has important clinical significance. The subretinal fluid of MNV may disrupt the centripetal and centrifugal traction balance, potentially promoting the progression of MTM. 10) Cases have been reported where mechanical elevation due to MNV exudation applied stress to the weakened foveal Müller cells, leading to full-thickness macular holes. 12)
Pathological myopia is accompanied by severe thinning of the choroid, so sympathetic ophthalmia rarely occurs after ocular surgery or trauma. Severe cases with complete disappearance of the choroid have been reported, 13) and special caution is required for intraocular surgery in eyes with pathological myopia.
Carlà et al. (2025) analyzed the natural history of myopic maculopathy in a European cohort of 1228 eyes with a mean follow-up of 11.5 years. 6) 57% showed progression of myopic maculopathy lesions during follow-up. 81% of localized atrophy progressed, of which 47% reached macular atrophy (OR 4.21). Active MNV developed in 15% of eyes at a mean of 4.5 years, and MNV development was significantly correlated with visual acuity decline (p=0.001) and progression to macular atrophy (OR 5.81). In type IX (septal) staphyloma, the progression rate reached 86%.
Although good visual improvement is achieved in the short term, long-term outcomes over 5 years are inferior to short-term results. Even after MNV regression, macular atrophy expands year by year, and suppressing the progression of atrophy remains a future challenge.
Bullimore et al. (2021) estimated that suppressing myopia progression by 1D significantly reduces the risk of macular degeneration, glaucoma, cataract, and retinal detachment. 8)
The NNT for myopia-related visual impairment was calculated to be 4.1 to 6.8. It is predicted that 50% of the world population will have myopia by 2050, and the public health significance of progression control is substantial. 8)
Low-concentration atropine eye drops, orthokeratology, multifocal soft contact lenses, and red light therapy are being studied as main methods for myopia progression control, but verification of their long-term preventive effects on fundus lesions is ongoing.
OCT-A Angio-B mode may be able to detect early MNV that is difficult to detect with structural OCT or fluorescein angiography. 11) High-precision evaluation of staphyloma using wide-field OCTA is also advancing. 14)
Research is progressing on collagen crosslinking of the sclera to suppress axial elongation. Methods using riboflavin-UVA irradiation and chemical crosslinking agents are being investigated, but safety and efficacy have not yet been established.
Slowing myopia progression in childhood reduces the risk of future complications. It has been shown that each 1D increase in myopia increases the risk of macular degeneration, glaucoma, cataracts, and retinal detachment. 8) Regular eye examinations, ensuring outdoor activity, and considering progression control therapies such as low-dose atropine eye drops or orthokeratology as needed are recommended.
