Pathologic myopia.

Pathologic myopia (PM) represents a predominant cause of irreversible visual loss worldwide, characterised by progressive axial elongation and profound structural alterations in the posterior segment, notably posterior staphyloma. Posterior staphyloma is a cardinal feature of PM and must be differentiated from physiological myopia, as it indicates localised scleral thinning and ectasia directly impacting the macula and optic nerve. Vision-threatening complications such as myopic traction maculopathy (MTM), frequently driven by vitreoretinal traction on retinal vasculature, and macular atrophy secondary to myopic macular neovascularisation (MNV) are prevalent in PM, often culminating in severe visual impairment. The sclera serves a critical biomechanical role in maintaining ocular structural integrity; hence, targeted interventions aimed at reinforcing the posterior sclera may decelerate disease progression. Although three-dimensional magnetic resonance imaging (3D MRI) has been extensively utilised to visualise the entire shape of the eye, recent advancements such as ultra-widefield optical coherence tomography (UWF-OCT) permit more detailed, practical assessment of posterior segment alterations. Furthermore, polarisation-sensitive OCT (PS-OCT) offers non-invasive in vivo evaluation of scleral collagen fibre orientation and birefringence, deepening our understanding of staphyloma pathogenesis. Early detection of structural changes within the sclera and vitreoretinal interface is paramount for timely intervention to prevent irreversible neuroretinal damage.