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showed that PDT resulted in fewer retreatments with stabilization or improvement in vision in 76% of eyes up to 12 months, beyond which reading ability starts to deteriorate largely due to the progressive chorioretinal atrophy surrounding the involuted mCNV. Intravitreal injections with anti-VEGF agents, such as ranibizumab and bevacizumab, result in a rapid return of vision with resolution of the hemorrhages and involution of the mCNV. It also potentially causes less damage to the surrounding choroid and retinal pigment epithelium. The SNEC experience is that whilst there is faster visual recovery compared to treatment with PDT with better visual outcome at 12 months (Fig. 4). With PDT, there is initial visual improvement but after 6 months, the visual outcome tends towards that of natural history, probably due to the inevitable development of chorioretinal atrophy.

Currently, it is possible to result in involution of the mCNV. The real challenge in the management of mCNV is to halt the progressive chorioretinal atrophy, which at this point in time is not possible.

Myopic Foveoschisis

As a consequence of the ectasia secondary to the posterior staphyloma, highly myopic individuals can develop foveoschisis. This is the splitting of the retinal layers in the macula (Fig. 5), which can cause blurring of vision

Figure 5. There is splitting of the retinal layers of the macula in the presence of myopic foveoschisis as seen on this OCT scan.

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and metamorphopsia. It can then progress on to a myopic macular hole formation that may be associated with a retinal detachment.

Surgical intervention may be necessary to restore the anatomy and visual function. The surgical procedures that have been performed include vitrectomy with gas tamponade and macular buckling.

Myopic macular hole detachments

Macular holes can develop in highly myopic eyes. This usually occurs as a consequence of tractional forces from the vitreoretinal interface (Fig. 6). Often, a localized detachment arises within the macula, which over time, can extend peripherally (Fig. 7).

Surgery would be warranted for re-establishment of anatomy, and this would involve a vitrectomy with clearance of the posterior cortical vitreous and peeling of the internal limiting membrane with internal gas tamponade and face down posturing postoperation. The surgery is challenging, as the retina is usually thin and atrophic, while the retinal pigment epithelium is also very thin, and not uncommonly, there is only bare sclera. Hence, other adjunctive measures have been proposed such as the macula buckle and cryopexy or photocoagulation of the edge of the

Figure 6. Myopic macular hole.

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As the margin of lattice degeneration is associated with vitreous adhesions, posterior vitreous detachments can result in a tractional retinal tear along the edges of the lesion. Despite the risk of developing retinal tears and retinal detachments, prophylactic laser of lattice degeneration as a means to prevent retinal detachment is not universally accepted. This is usually recommended if there is a symptomatic retinal tear or a history of retinal detachment in the fellow eye.

Retinal tears and detachments

Retinal detachments (Fig. 8) occur in about one in 10,000 of the population.11 This increases with increasing degrees of myopia. 67 percent of detachments occur in eyes with myopia. The myopic eyes that develop retinal detachments tend to be younger than those whose detachments occur as a consequence of posterior vitreous detachment. It is also not infrequent that these individuals are found to have bilateral retinal detachments, which may be asymptomatic.

Figure 8. Peripheral lattice degeneration with pigmentation and an atrophic round hole within.