OPTO 2nd Sem Midterm

• At birth, the eyes are not associated with each other but act as two independent sense organs
• In newborns, the first sign of the development of fixation reflex appears when the eyes follow light
• At the age of two months, the eyes follow large objects
• The foveas are not fully formed until the third month of life
• At three months, they hold objects
• At six months, fixates at an object for one to two minutes
• At birth, vision is no greater than 5/200 (subnormal VA), the eye is normally hyperopic because the ciliary muscles are not yet fully developed
• By one year old VA is 20/70, and at three years old, it is 20/20
• Fusional mechanism becomes fully developed from one to one and a half years of life
• Accommodation develops with sharpening of visual acuity at the age of three
• Parallel incident light is focused in front of the retina in myopia
• Parallel incident light is focused behind the retina in hyperopia
• Refractive ametropia is due to incorrect power of the cornea and/or the crystalline lens
• Axial ametropia is due to incorrect axial length of the eyeball
• Combined ametropia is a combination of both refractive and axial ametropias
• Myopia can occur with or without astigmatism
• Hyperopia can occur with or without astigmatism
• Astigmatism is a type of ametropia
• Presbyopia is an age-related condition
• Eye growth is most rapid during the first two years of life
• The powers of the eye's refracting components adjust to compensate for growth
• Emmetropization is the process of reducing refractive error between birth and six years of age
• Changes in emmetropization are both spherical and astigmatic
• Increased axial length is compensated for by corneal and lens curvature changes
• Astigmatism shows a significant decrease during the first two years of life
• The refractive status of premature babies ranges from -1.30 D to +1.00 D
• The refractive status of full-term babies ranges from +0.60 D to +2.60 D
• At 6 years old, the refractive status ranges from -0.50 D to +3.00 D
• Hyperopic individuals become less hyperopic as they age
• At birth, the eyes are not associated with each other but act as two independent sense organs
• In newborns, the first sign of the development of fixation reflex appears when the eyes follow light
• At two months of age, the eyes follow large objects
• The foveas are not fully formed until the third month of life
• At three months, infants can hold objects
• At six months of age, an infant can fixate at an object for one to two minutes
• At birth, vision is no greater than 5/200 (subnormal VA) and the eye is normally hyperopic because the ciliary muscles are not yet fully developed
• By one year old, visual acuity (VA) is 20/70, and at three years old, it is 20/20
• The fusional mechanism becomes fully developed from one to one and a half years of life
• Accommodation develops with sharpening of visual acuity at the age of three
• Emmetropia: Parallel incident light is focused on the retina