08 Jun Near-Sightedness (Myopia) causes Vitreous Floaters
Floaters arise from the vitreous body, the gel that fills the center of the eye. Myopia is the clinical term for near-sightedness that is due to abnormal elongation of the eye. A common reason to perform vitrectomy (surgery to remove the gel in the center of the eye) in patients with Vision Degrading Myodesopsia (clinically significant vitreous floaters) is myopic vitreopathy (abnormalities in vitreous related to near-sightedness). Yet, little was known about the relationship between myopia, vitreous structure, and visual function, until now.
A recent study (https://doi.org/10.1016/j.ajo.2020.09.017) correlated length of the eye with vitreous density, as quantified with ultrasound (https://doi.org/10.1167/iovs.14-15414), and contrast sensitivity function (https://doi:10.1007/s00417-018-3957-1 and https://doi.org/10.1167/iovs.14-15414). The results showed that the longer the eye, the greater the vitreous echodensity and the worse the vision. This explains dissatisfaction with vision that is often expressed by myopic patients. Given the impending global explosion of myopia (https://doi.org/10.1016/j.ophtha.2016.01.006), Vision Degrading Myodesopsia induced by myopic vitreopathy may become a significant international health issue. Although vitrectomy is safe and effective (https://doi:10.1016/j.oret.2018.03.011), the magnitude of the burgeoning global epidemic of myopia makes a surgical approach untenable on a broad scale, and less invasive/costly treatments are needed.
- Axial myopia has increased vitreous echodensity and decreased contrast sensitivity.
- PVD further increases vitreous density and degrades contrast sensitivity in myopia.
- Limited vitrectomy normalizes contrast sensitivity function in myopic vitreopathy.
Read about the study here: https://www.ajo.com/article/S0002-9394(20)30511-0/fulltext