Unit 3:
Alterations and Disorders of the Head, Eyes, Ears, Nose, and Throat
In general, children should achieve a visual acuity of 20/20 by the age of 5 to 6 years old. However, some children may reach
this level of acuity a bit earlier or later depending on their development.
As for when to refer a child to an ophthalmologist, here are some common guidelines from chapter 5 or similar clinical
references:
• Before age 3: If a child shows signs of abnormal eye movements, crossed eyes (strabismus), or a significant difference
in vision between the eyes, they should be referred.
• After age 3: If a child has not passed a standard vision screening or has persistent issues such as squinting, holding
objects very close to their face, difficulty with hand-eye coordination, or complains of headaches, a referral is
warranted.
• Any age: If there are concerns about color vision abnormalities, if the child’s vision has worsened, or if any systemic
conditions might be affecting eye health (like diabetes or other neurological conditions), referral is important.
What is a Snellen test used for? How is it administered
The Snellen test is used to assess visual acuity, particularly for detecting refractive errors like nearsightedness (myopia),
farsightedness (hyperopia), and astigmatism. It measures the clarity or sharpness of vision at a specific distance.
Administration of the Snellen Test:
• Setup:
• The patient is positioned 20 feet away from the Snellen chart (which has letters in progressively smaller
sizes).
• If the test is conducted at a closer distance (e.g., 10 feet), the results are adjusted to 20 feet equivalent.
• Procedure:
• The patient is asked to cover one eye (with a patch or by using their hand).
• The patient reads the smallest line of letters they can see clearly.
• The process is repeated for the other eye.
• Results are recorded in terms of 20/x, where "x" is the smallest line of letters the patient can read.
Interpretation:
• A result of 20/20 means the patient sees at 20 feet what a normal person would see at 20 feet.
• If the result is 20/40, the patient can see at 20 feet what a normal person would need to be 40 feet away to see.
This test helps identify individuals who may need corrective lenses or further eye examination.
What test checks for colorblindness
,Ishihara Color Test:
• Purpose: Detects color vision deficiencies, especially red-green blindness.
• Test Setup:
• The test consists of a series of plates containing colored dots arranged in a way that forms numbers or
patterns visible to those with normal color vision, but not to those with certain types of colorblindness.
• The plates typically use a mixture of colored dots (such as red and green) on a background of
contrasting dots.
Administration:
• The patient is shown a series of Ishihara plates and asked to identify the number or shape they see.
• If a person is unable to identify the number or pattern, it suggests a color vision deficiency.
Interpretation:
• Normal Vision: The patient can correctly identify all or most of the numbers/patterns on the plates.
• Colorblindness: The patient may fail to see certain numbers or patterns, indicating a red-green color vision
deficiency or, less commonly, blue-yellow deficiencies.
How do you test vision in an illiterate person
Tumbling E Chart:
• Purpose: Assesses visual acuity in individuals who cannot read letters.
• Test Setup:
• The chart features the letter "E" in various orientations (up, down, left, right) instead of standard
letters.
• The patient is asked to indicate the direction the "E" is pointing (using either their finger or a response
method such as verbally).
• Administration:
• The patient is asked to sit at a specific distance (usually 20 feet) from the chart.
• The patient covers one eye and is asked to identify the direction of the "E" on the chart. This process is
repeated for the other eye.
• Interpretation:
• The results are recorded similarly to the Snellen chart (e.g., 20/20, 20/40) based on the smallest
orientation the patient can identify clearly.
LEA Symbols Chart:
• Purpose: Assesses visual acuity in illiterate children or those who do not understand letters.
• Test Setup:
, • The chart uses familiar symbols, such as circles, squares, or pictures.
• The patient is asked to identify the symbols.
• Administration:
• Like the Tumbling E chart, the patient sits at a designated distance (usually 10 feet for children).
• The patient identifies the symbols, and results are recorded similarly.
Conclusion:
• Both tests are designed to measure visual acuity without relying on reading skills, making them ideal for
illiterate individuals or those who cannot recognize letters. The tests assess the clarity of vision and can be used
in both adults and children.
What are some of the most common kind of eye pathologies
1. Myopia (Nearsightedness):
• Pathophysiology: The eye is elongated, causing light to focus in front of the retina, leading to difficulty seeing distant
objects clearly.
• Symptoms: Blurry vision when looking at distant objects.
• Correction: Concave lenses (glasses or contact lenses) to spread the light rays.
2. Hyperopia (Farsightedness):
• Pathophysiology: The eye is too short, causing light to focus behind the retina, making close objects appear blurry.
• Symptoms: Difficulty focusing on near objects, eye strain, and headaches when reading.
• Correction: Convex lenses to converge light rays.
3. Astigmatism:
• Pathophysiology: Irregular curvature of the cornea or lens causes light to focus on multiple points, leading to blurred
vision.
• Symptoms: Blurred or distorted vision at all distances.
• Correction: Cylindrical lenses to correct for the uneven curvature.
4. Presbyopia:
• Pathophysiology: Age-related loss of lens elasticity, resulting in difficulty focusing on near objects.
• Symptoms: Difficulty reading small print or seeing close-up objects clearly, especially after the age of 40.
• Correction: Reading glasses or bifocals to assist in near vision.
5. Cataracts:
• Pathophysiology: Clouding of the eye's natural lens, usually due to aging, leading to blurry or dimmed vision.
• Symptoms: Blurred vision, glare, halos around lights, and difficulty seeing at night.
, • Treatment: Surgical removal of the cataract and lens replacement.
6. Glaucoma:
• Pathophysiology: Increased intraocular pressure (IOP) that damages the optic nerve, leading to peripheral vision loss.
• Types:
• Open-angle glaucoma (chronic, gradual loss of vision)
• Angle-closure glaucoma (acute, sudden increase in IOP)
• Symptoms: Often asymptomatic in the early stages, but may include peripheral vision loss and tunnel vision.
• Treatment: Medications (e.g., beta-blockers, prostaglandin analogs), laser therapy, or surgery to lower IOP.
7. Age-Related Macular Degeneration (AMD):
• Pathophysiology: Degeneration of the macula (the central part of the retina) leads to loss of central vision.
• Symptoms: Blurry vision or blind spots in the central visual field, difficulty reading or recognizing faces.
• Types:
• Dry AMD (gradual deterioration of retinal cells)
• Wet AMD (growth of abnormal blood vessels under the retina, causing leakage and damage).
• Treatment: Anti-VEGF injections (for wet AMD), dietary supplements (for dry AMD).
8. Diabetic Retinopathy:
• Pathophysiology: Damage to the blood vessels of the retina due to prolonged high blood sugar levels, leading to
leakage, hemorrhage, and vision problems.
• Symptoms: Blurred vision, floaters, and potential vision loss if untreated.
• Treatment: Tight glucose control, laser treatment, and anti-VEGF therapy.
9. Conjunctivitis (Pink Eye):
• Pathophysiology: Inflammation of the conjunctiva caused by infection (bacterial, viral) or allergies.
• Symptoms: Redness, itching, tearing, discharge, and sometimes swelling.
• Treatment: Antibiotics (for bacterial), supportive care (for viral), or antihistamines (for allergic).
10. Retinal Detachment:
• Pathophysiology: Separation of the retina from the underlying tissue, disrupting its function.
• Symptoms: Sudden onset of floaters, flashes of light, or a curtain-like shadow over the visual field.
• Treatment: Urgent surgical intervention (laser therapy or vitrectomy) to reattach the retina.
What are conditions that are associated with Increased Cranial Pressure (ICP)?
1. Myopia (Nearsightedness):
• Pathophysiology: The eye is elongated, causing light to focus in front of the retina, leading to difficulty seeing distant
objects clearly.
Alterations and Disorders of the Head, Eyes, Ears, Nose, and Throat
In general, children should achieve a visual acuity of 20/20 by the age of 5 to 6 years old. However, some children may reach
this level of acuity a bit earlier or later depending on their development.
As for when to refer a child to an ophthalmologist, here are some common guidelines from chapter 5 or similar clinical
references:
• Before age 3: If a child shows signs of abnormal eye movements, crossed eyes (strabismus), or a significant difference
in vision between the eyes, they should be referred.
• After age 3: If a child has not passed a standard vision screening or has persistent issues such as squinting, holding
objects very close to their face, difficulty with hand-eye coordination, or complains of headaches, a referral is
warranted.
• Any age: If there are concerns about color vision abnormalities, if the child’s vision has worsened, or if any systemic
conditions might be affecting eye health (like diabetes or other neurological conditions), referral is important.
What is a Snellen test used for? How is it administered
The Snellen test is used to assess visual acuity, particularly for detecting refractive errors like nearsightedness (myopia),
farsightedness (hyperopia), and astigmatism. It measures the clarity or sharpness of vision at a specific distance.
Administration of the Snellen Test:
• Setup:
• The patient is positioned 20 feet away from the Snellen chart (which has letters in progressively smaller
sizes).
• If the test is conducted at a closer distance (e.g., 10 feet), the results are adjusted to 20 feet equivalent.
• Procedure:
• The patient is asked to cover one eye (with a patch or by using their hand).
• The patient reads the smallest line of letters they can see clearly.
• The process is repeated for the other eye.
• Results are recorded in terms of 20/x, where "x" is the smallest line of letters the patient can read.
Interpretation:
• A result of 20/20 means the patient sees at 20 feet what a normal person would see at 20 feet.
• If the result is 20/40, the patient can see at 20 feet what a normal person would need to be 40 feet away to see.
This test helps identify individuals who may need corrective lenses or further eye examination.
What test checks for colorblindness
,Ishihara Color Test:
• Purpose: Detects color vision deficiencies, especially red-green blindness.
• Test Setup:
• The test consists of a series of plates containing colored dots arranged in a way that forms numbers or
patterns visible to those with normal color vision, but not to those with certain types of colorblindness.
• The plates typically use a mixture of colored dots (such as red and green) on a background of
contrasting dots.
Administration:
• The patient is shown a series of Ishihara plates and asked to identify the number or shape they see.
• If a person is unable to identify the number or pattern, it suggests a color vision deficiency.
Interpretation:
• Normal Vision: The patient can correctly identify all or most of the numbers/patterns on the plates.
• Colorblindness: The patient may fail to see certain numbers or patterns, indicating a red-green color vision
deficiency or, less commonly, blue-yellow deficiencies.
How do you test vision in an illiterate person
Tumbling E Chart:
• Purpose: Assesses visual acuity in individuals who cannot read letters.
• Test Setup:
• The chart features the letter "E" in various orientations (up, down, left, right) instead of standard
letters.
• The patient is asked to indicate the direction the "E" is pointing (using either their finger or a response
method such as verbally).
• Administration:
• The patient is asked to sit at a specific distance (usually 20 feet) from the chart.
• The patient covers one eye and is asked to identify the direction of the "E" on the chart. This process is
repeated for the other eye.
• Interpretation:
• The results are recorded similarly to the Snellen chart (e.g., 20/20, 20/40) based on the smallest
orientation the patient can identify clearly.
LEA Symbols Chart:
• Purpose: Assesses visual acuity in illiterate children or those who do not understand letters.
• Test Setup:
, • The chart uses familiar symbols, such as circles, squares, or pictures.
• The patient is asked to identify the symbols.
• Administration:
• Like the Tumbling E chart, the patient sits at a designated distance (usually 10 feet for children).
• The patient identifies the symbols, and results are recorded similarly.
Conclusion:
• Both tests are designed to measure visual acuity without relying on reading skills, making them ideal for
illiterate individuals or those who cannot recognize letters. The tests assess the clarity of vision and can be used
in both adults and children.
What are some of the most common kind of eye pathologies
1. Myopia (Nearsightedness):
• Pathophysiology: The eye is elongated, causing light to focus in front of the retina, leading to difficulty seeing distant
objects clearly.
• Symptoms: Blurry vision when looking at distant objects.
• Correction: Concave lenses (glasses or contact lenses) to spread the light rays.
2. Hyperopia (Farsightedness):
• Pathophysiology: The eye is too short, causing light to focus behind the retina, making close objects appear blurry.
• Symptoms: Difficulty focusing on near objects, eye strain, and headaches when reading.
• Correction: Convex lenses to converge light rays.
3. Astigmatism:
• Pathophysiology: Irregular curvature of the cornea or lens causes light to focus on multiple points, leading to blurred
vision.
• Symptoms: Blurred or distorted vision at all distances.
• Correction: Cylindrical lenses to correct for the uneven curvature.
4. Presbyopia:
• Pathophysiology: Age-related loss of lens elasticity, resulting in difficulty focusing on near objects.
• Symptoms: Difficulty reading small print or seeing close-up objects clearly, especially after the age of 40.
• Correction: Reading glasses or bifocals to assist in near vision.
5. Cataracts:
• Pathophysiology: Clouding of the eye's natural lens, usually due to aging, leading to blurry or dimmed vision.
• Symptoms: Blurred vision, glare, halos around lights, and difficulty seeing at night.
, • Treatment: Surgical removal of the cataract and lens replacement.
6. Glaucoma:
• Pathophysiology: Increased intraocular pressure (IOP) that damages the optic nerve, leading to peripheral vision loss.
• Types:
• Open-angle glaucoma (chronic, gradual loss of vision)
• Angle-closure glaucoma (acute, sudden increase in IOP)
• Symptoms: Often asymptomatic in the early stages, but may include peripheral vision loss and tunnel vision.
• Treatment: Medications (e.g., beta-blockers, prostaglandin analogs), laser therapy, or surgery to lower IOP.
7. Age-Related Macular Degeneration (AMD):
• Pathophysiology: Degeneration of the macula (the central part of the retina) leads to loss of central vision.
• Symptoms: Blurry vision or blind spots in the central visual field, difficulty reading or recognizing faces.
• Types:
• Dry AMD (gradual deterioration of retinal cells)
• Wet AMD (growth of abnormal blood vessels under the retina, causing leakage and damage).
• Treatment: Anti-VEGF injections (for wet AMD), dietary supplements (for dry AMD).
8. Diabetic Retinopathy:
• Pathophysiology: Damage to the blood vessels of the retina due to prolonged high blood sugar levels, leading to
leakage, hemorrhage, and vision problems.
• Symptoms: Blurred vision, floaters, and potential vision loss if untreated.
• Treatment: Tight glucose control, laser treatment, and anti-VEGF therapy.
9. Conjunctivitis (Pink Eye):
• Pathophysiology: Inflammation of the conjunctiva caused by infection (bacterial, viral) or allergies.
• Symptoms: Redness, itching, tearing, discharge, and sometimes swelling.
• Treatment: Antibiotics (for bacterial), supportive care (for viral), or antihistamines (for allergic).
10. Retinal Detachment:
• Pathophysiology: Separation of the retina from the underlying tissue, disrupting its function.
• Symptoms: Sudden onset of floaters, flashes of light, or a curtain-like shadow over the visual field.
• Treatment: Urgent surgical intervention (laser therapy or vitrectomy) to reattach the retina.
What are conditions that are associated with Increased Cranial Pressure (ICP)?
1. Myopia (Nearsightedness):
• Pathophysiology: The eye is elongated, causing light to focus in front of the retina, leading to difficulty seeing distant
objects clearly.
