3.1.5 Flashcards
What is the primary purpose of visual field testing?
Diagnosing and managing ocular and neurological conditions
Visual field testing is essential for detecting conditions like glaucoma, neurological disorders, and retinal diseases.
What visual field defects are commonly associated with glaucoma?
Nasal steps and arcuate scotomas
These defects may progress to tunnel vision if untreated.
Which types of neurological conditions can be identified through visual field defects?
Strokes, brain tumors, multiple sclerosis, trauma
Each can lead to specific visual field defects based on the area affected.
What visual field defect can occur with a stroke affecting the occipital lobe?
Homonymous hemianopia
What visual field defect can a pituitary tumor cause?
Bitemporal hemianopia
Name a condition that causes progressive peripheral field loss.
Retinitis pigmentosa
What is the effect of hydroxychloroquine toxicity on visual fields?
Central and paracentral scotomas
Fill in the blank: Visual field tests can reveal functional _______ or organic causes of vision loss.
non-organic
What is the most commonly used method of visual field assessment?
Automated Perimetry (Static Perimetry)
What is the Humphrey Field Analyzer (HFA) primarily used for?
Detecting and monitoring visual field defects
What testing strategies does the Humphrey Field Analyzer offer?
- 24-2
- 30-2
- 10-2
- SITA Standard
- SITA Fast
What is the purpose of Kinetic Perimetry?
Mapping large field defects
What is Goldmann Perimetry best suited for?
Patients with low vision and irregular field loss
Which visual field test is used for macular disease screening?
Amsler Grid
What component is crucial to monitor during visual field testing?
Fixation monitoring
True or False: High fixation losses indicate reliable results.
False
What does a total deviation plot highlight in visual field testing?
Areas where sensitivity is reduced compared to age-matched normals
What type of visual field defect is associated with optic nerve lesions?
Monocular defects
What visual field defect is characteristic of optic chiasm lesions?
Bitemporal hemianopia
What does inferior quadrantanopia indicate?
Parietal lobe lesions
What is the significance of the Henson 9000 Perimeter?
Designed for glaucoma screening and monitoring
What is the ZATA strategy in the Henson 9000?
Zippy Adaptive Threshold Algorithm for efficient testing
What is the focus of the 26-Point Suprathreshold Test?
Detecting early glaucomatous damage
Fill in the blank: The Henson 9000 perimeter is ideal for _______ clinics.
high-volume
Which test is particularly useful for conditions affecting the macula?
10-2 Testing
What adjustments should be made for patients with reduced visual acuity?
- Increase stimulus size
- Adjust fixation targets
- Use appropriate refractive correction
What is the difference between threshold tests and suprathreshold tests?
Threshold tests take longer and require concentration; suprathreshold tests are faster and simpler.
What is the most likely diagnosis for a patient with an arcuate scotoma on a 24-2 test?
Primary open-angle glaucoma (POAG)
Arcuate scotomas are commonly seen in early glaucoma and follow the shape of the optic nerve fibers.
Why is a 10-2 test more appropriate for a patient on hydroxychloroquine?
It provides dense central testing in the 10-degree central visual field where central visual defects commonly occur
Hydroxychloroquine toxicity can cause paracentral scotomas or bull’s eye maculopathy.
What should be the next step after a 26-Point Suprathreshold Test shows defects?
Perform a full threshold test to confirm the nature of the defect and quantify its severity
A ZATA Standard 24-2 test would be appropriate.
What factors could cause a false visual field defect?
Factors include:
* Poor fixation
* Refractive errors
* Media opacities
* Inattention or fatigue
* Neurological factors
Each factor has specific solutions to address them.
Where is the likely location of the lesion in a patient with homonymous hemianopia?
Optic tract or optic radiations
This indicates a lesion beyond the optic chiasm, often due to stroke, tumor, or traumatic brain injury.
What does a central scotoma on a 10-2 test indicate?
Loss of vision in the very center of the visual field
This may suggest conditions like macular degeneration or hydroxychloroquine toxicity.
How does the ZATA Fast test differ from the ZATA Standard test?
ZATA Fast is a quick screening test, while ZATA Standard is a detailed adaptive threshold test
ZATA Fast is used for initial screenings; ZATA Standard is used for confirming diagnosis and monitoring.
How would you interpret a visual field with bitemporal hemianopia?
Loss of vision in the outer half of the visual field in both eyes
This is often associated with lesions at the optic chiasm, commonly caused by a pituitary tumor.
Which part of RNFL is damaged in superior arcuate defect
Inferior RNFL (which corresponds to to upper visual field due to inverted projection of the retina onto the visual cortex)
