Page 165 - July-August 2020

MYOPIA PROGRESSION

AND CONTROL

M yopia is the state of LAG OF ACCOMMODATION

refraction in which parallel
THEORY
rays of light from an
object at infinity are brought to It is thought that high lag of
focus in front of the retina when accommodation occurs during near
1
accommodation is at rest. The high work in myopic eyes which cause
Prof Monica Chaudhry myopia increases the risk for vision foveal hyperopic retinal blur (fig 1).
Director Sushant School of Health threatening complications like This foveal hyperopic retinal blur
Sciences, Ansal retinal and vitreous detachments, acts as a stimulus for elongation
University, Gurugram cataracts, glaucoma, and myopic of eyeball leading to increase in
6
CO-AUTHORS macular degenerations by many myopia. This is supported by the fact
folds. Myopia develops mostly that myopic children have reduced
2
in early childhood which tends to accommodative response compared
progress in later life. However, the to Emmetropes, a debatable fact
exact mechanism involved behind at present. Bifocals and progressive
progression of myopia is unclear additional lens used for control of
although several theories have been myopia are based on this theory.
put forward which include: MECHANICAL TENSION
1. Lag of accommodation theory THEORY
2. Mechanical tension theory This theory is based on the finding
3. Peripheral hyperopic defocus that the eye responds to the transient
Kamal Thakur theory changes in axial length following
M.OPTOM, Ansal University,
Gurugram

Sushant Shah
MSc Optometry, Ansal University,
Gurugram FIG 1: FOVEAL HYPEROPIC DEFOCUS DUE TO REDUCE ACCOMMODATIVE RESPONSE

JULY-AUG 2020 | 161 Myopia