**Conflict of interest**

*Intraocular Lens*

As above mentioned, when complications due to high myopia occur, we talk about pathologic myopia. Many complications can develop, and their treatment can count mainly on surgery and anti-VEGF therapy. When treatment is not possible or after this in order to boost and maximize the visual recovery, ophthalmologist can recur to visual rehabilitation strategies. These can count into two main categories of tools: visual stimulation and visual aids. Acoustic biofeedback is one of the most effective techniques in order to stimulate visual system. First of all, it is mandatory to analyze the characteristics of the visual field defects that are affecting the patient. Two types of defects can occur in such patients: central scotomas (of various shape, size, and depth) and peripheral defects. The two can also occur simultaneously in various combinations. Then, in case of a central defect, after analyzing patient's retinal sensitivity and fixation stability with a microperimetry, if the patient has already developed a preferred retinal locus (PRL or pseudofovea) by itself, it is possible to stimulate this one if it is in a favorable position in order to boost fixation stability or to choose a new point to relocate the PRL in a position that the physician considers more favorable for the patient because of a better residual retinal sensitivity. A PRL is a point that the patient with a central scotoma uses to fixate object, as a "substitute" of the natural impaired fovea. This point is chosen considering patient's expectations, attitudes, activities and the residual sensitivity microperimetric map of the patient and the distance that the point candidate to be stimulated from the natural fovea. It means that for a better outcome it would be better to choose a point with the best residual retinal sensitivity not too far from the natural fovea if possible. Acoustic biofeedback is a technique that trains the patient relocating the PRL to a more useful position; when a point to become the new PRL is chosen by the examiner, during the acoustic biofeedback session, a beep is produced by the machine (microperimeter), and it becomes more continuous as the point to be stimulated gets closer to the center of the fixation target on the machine, hence training the patient to use the point set by the ophthalmologist. This one guides the patient during the whole session, giving him instructions where to move his gaze to match the trained PRL and the center of the fixation point of the machine. A typical acoustic biofeedback rehabilitation protocol is composed of 10 sessions of 10 min each, typically one session per week. However, it can be repeated if necessary. In case of a peripheral defect alone, acoustic biofeedback can be useful if an unstable fixation is present in order to stimulate the fixation point and make it more stable. Visual aid use can also benefit of a more stable fixation; they are available for distance and intermediate-near vision. For distance vision, the most popular devices are telescopes, Galilean, and Keplerian ones. They ideally "approach" far items to the observer by magnifying them. They can be monocular or binocular, clip-on, spectacle mounted, and handheld. For near vision, microscopic systems are available; they are high dioptric positive power lens that work by reducing focal length. There are many solutions that use this technology: handheld magnifiers, bar magnifiers, positive overcorrection of near prescription, visolettes, and prismatic hypercorrective are available in various spherical powers and so in various magnification power. Electronic aids for near vision are available, with portable and fixed CCTV being the mainstay of the category. Other solutions are also available such as braille systems (displays, printers, note takers), household, personal and other independent living products (for example, braille and talking watches, talking blood pressure and glucose meters, etc.), OCR systems, and audiobooks. Many recent apps for aided mobility, OCR, etc., have been placed on the market. In patients with peripheral visual field defects, field enhancement systems are very useful. Reversed telescopes and field expanding channel lens

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represent the mainstay of this category.

Enzo Maria Vingolo, Giuseppe Napolitano, and Lorenzo Casillo declare that they have no conflict of interest.
