NBEO Clinical Optometry & Patient Care — Questions and Answers
Question 1: What is refraction in an eye examination?
- The process of determining the correct lens prescription to correct refractive errors like myopia, hyperopia, and astigmatism (Correct answer)
- Measuring intraocular pressure
- Examining the retina
- Testing color vision
Correct answer: The process of determining the correct lens prescription to correct refractive errors like myopia, hyperopia, and astigmatism
Refraction uses objective (retinoscopy, autorefraction) and subjective (phoropter) techniques to determine the precise lens power needed to focus light correctly on the retina, correcting blurry vision.
Question 2: What is myopia and how is it corrected?
- Nearsightedness where distant objects are blurry because light focuses in front of the retina, corrected with minus (concave) lenses (Correct answer)
- Farsightedness corrected with plus lenses
- Loss of near focus due to aging
- Distorted vision due to irregular cornea
Correct answer: Nearsightedness where distant objects are blurry because light focuses in front of the retina, corrected with minus (concave) lenses
In myopia, the eye is too long or the cornea too steep, causing light to focus before the retina. Minus lenses diverge light rays so they focus correctly on the retina.
Question 3: What is glaucoma and how is it detected?
- A group of diseases that damage the optic nerve, often associated with elevated IOP, detected through tonometry, optic nerve evaluation, and visual field testing (Correct answer)
- A clouding of the lens
- An infection of the eyelid
- A corneal scratch
Correct answer: A group of diseases that damage the optic nerve, often associated with elevated IOP, detected through tonometry, optic nerve evaluation, and visual field testing
Glaucoma causes progressive, irreversible optic nerve damage and visual field loss. Detection requires IOP measurement, optic disc evaluation (cupping), OCT nerve fiber analysis, and perimetry (visual field testing).
Question 4: What is a slit lamp examination?
- A biomicroscopic examination using a high-intensity light source and magnification to examine the anterior and posterior segments of the eye in detail (Correct answer)
- An examination using a penlight only
- A test of eye movement
- A measurement of visual acuity
Correct answer: A biomicroscopic examination using a high-intensity light source and magnification to examine the anterior and posterior segments of the eye in detail
The slit lamp biomicroscope projects a thin beam of light at various angles and widths while providing magnified stereoscopic views, allowing detailed examination of the lids, conjunctiva, cornea, iris, lens, and with accessories, the retina.
Question 5: What is diabetic retinopathy?
- Damage to retinal blood vessels caused by diabetes, progressing from microaneurysms to proliferative neovascularization that can cause blindness (Correct answer)
- A type of glaucoma
- A refractive error
- An eyelid infection
Correct answer: Damage to retinal blood vessels caused by diabetes, progressing from microaneurysms to proliferative neovascularization that can cause blindness
Diabetic retinopathy damages retinal capillaries, causing microaneurysms, hemorrhages, exudates, and in advanced stages, neovascularization that can lead to vitreous hemorrhage and tractional retinal detachment.
Question 6: What is age-related macular degeneration (AMD)?
- A progressive disease affecting the macula causing central vision loss, existing in dry (atrophic) and wet (neovascular) forms (Correct answer)
- A type of cataract
- An infection of the macula
- A congenital condition present at birth
Correct answer: A progressive disease affecting the macula causing central vision loss, existing in dry (atrophic) and wet (neovascular) forms
Dry AMD (85-90% of cases) involves drusen deposits and atrophy. Wet AMD involves abnormal blood vessel growth under the retina that leaks fluid and blood, causing rapid central vision loss. Anti-VEGF injections treat wet AMD.
NBEO Clinical Optometry & Patient Care
What is refraction in an eye examination?