Imaging in myopia

Advances in ocular imaging devices including optical coherence tomography, ultrasound, and magnetic resonance imaging have enabled the visualization of pathological myopia characterized by the excessive elongation of the eye, thereby identifying microscopic changes ranging from the posterior segment (sclera, choroid, retina, and/or the optic nerve) to the anterior segment. Imaging-derived measures or imaging biomarkers are thus potentially useful in assessing degenerative changes occurring in the myopic fundus, in evaluating the early changes preceding myopic macular degeneration, and in providing objective measures of ocular structures to aid in detecting staphyloma formation and progression, myopic macular degeneration-tilted disc syndrome, and glaucoma in high myopes. However, imaging the highly myopic eye is not straightforward and is associated with challenges such as optics-related aberrations, focusing ability of current devices, and morphological alterations of the myopic fundus and optic nerve. Finally, the strengths and weaknesses of each of these imaging modalities in relation to high myopia have been discussed. An understanding of the imaging of microstructural changes associated with pathological myopia, challenges associated with imaging devices, and potential usefulness and limitations of imaging devices will better inform clinicians of its future potential in the diagnosis and management of vision-threatening complications associated with pathological myopia.