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the laser-induced scar enlarged obviously in the first three months, accompanied by decreased visual
[109]
acuity . Expansion of the laser-induced scar is another cause of visual loss, and it has been regarded as a
[109]
potential vision-threatening late complication .
PDT with verteporfin was a therapeutic modality to treat subfoveal CNV. Patients received an intravenous
injection of a photosensitizer named verteporfin and application of a specific wavelength of laser light to the
target lesion . Verteporfin can bind to endogenous lipoproteins overexpressed on neovascular endothelial
[110]
cells. After activation by laser, verteporfin leads to occlusion of the targeted CNV. Compared with laser
photocoagulation, PDT induces selective occlusion of the CNV without injuring the surrounding
neurosensory retina and RPE . The efficacy and safety of PDT in mCNV have been approved [103,112,113] , and
[111]
the recurrence rate after treatment is around 50% [114,115] . In a meta-analysis, anti-VEGF therapy gained better
[116]
vision in mCNV patients than photodynamic therapy (PDT) or laser photocoagulation . In the
RADIANCE study (Ranibizumab and PDT evaluation in myopic choroidal neovascularization) published in
2014 , the efficacy and safety were compared between ranibizumab 0.5 mg intravitreal injection and
[93]
verteporfin photodynamic therapy (vPDT). Patients with mCNV were randomly assigned to ranibizumab
treatment guided by visual acuity stabilization criteria (Group 1), ranibizumab treatment guided by disease
activity criteria (Group 2), and the vPDT group. Patients in the vPDT group could switch to ranibizumab
three months after the initial vPDT. Ranibizumab achieved a rapid improvement in BCVA in Groups 1 and
2 during the first three months and a stable improvement up to the endpoint. The vPDT group improved
lower BCVA compared to the ranibizumab group during the first three months. Then, 73% of participants
with lower BCVA change in the vPDT group switched to the ranibizumab group. At 12-month follow-up,
the mean BCVA improved 13.8 ± 11.42 letters in Group 1, 14.4 ± 10.2 letters in Group 2, and 9.3 letters in
the vPDT group. Replicated injections were requested in the ranibizumab group. The median number of
ranibizumab injections was four in Group 1 and two in Group 2. In addition to better visual outcomes in
the ranibizumab groups, the RADIANCE study also demonstrated that an individualized regimen could
achieve optimal visual outcomes.

Due to its advantages in terms of visual outcome and convenient intravitreal injection of drugs, anti-VEGF
[102]
therapy has become the major treatment of mCNV .

Surgical interventions to myopic maculopathy
Posterior scleral reinforcement
Axial elongation contributes to myopic maculopathy. The thin sclera, especially the posterior pole of the
globe, facilitates excessive ocular enlargement. Sclera is regarded as a prime target to stop the progression of
myopia. Currently, reinforcement of the posterior sclera by different surgical methods is the only available
way to managescleral ectasia.

Posterior scleral reinforcement (PSR) was first proposed by Shevelev in 1930, modified by Borley and
[117]
[118]
Snyder in 1958, and then simplified by Thompson in 1978. The surgical process has kept innovating in
[119]
the following decades. The main procedure of PSR is placing a strip (sclera from donor’s eye, fascia lata
[121]
strip or duramater from cadaver, or biomaterial patch) over the posterior pole to strengthen the
[120]
posterior sclera and halt axial elongation. In most of the reports on PSR, the results are favorable with stable
visual acuity as well as a lower increase in refractive error and AL [121-124] . According to Curtin’s grade of
[125]
posterior staphyloma, the most common staphyloma developed on the nasal side of optic nerve .
Therefore, Curtin pointed out that PSR did not protect against staphyloma, which is not located in the
macula . In fact, the purpose of PSR is to preserve central visual acuity. Staphyloma located outside
[126]
macula would not affect the visual outcome of PSR.