Diagnostic Testing and Equipment Flashcards
6 cards from real Vision and Ophthalmology practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 Diagnostic Testing and Equipment flashcards as text
Optical coherence tomography (OCT) uses which type of light to generate cross-sectional retinal images?
Answer: Near-infrared light
OCT uses near-infrared light interferometry to generate high-resolution cross-sectional images of retinal layers with micrometer-level resolution.
The Goldmann applanation tonometer measures IOP by:
Answer: Flattening a known area of the cornea (3.06 mm diameter)
Goldmann applanation tonometry measures the force required to flatten a standardized area (3.06 mm diameter) of the cornea, which correlates with IOP by the Imbert-Fick principle.
Fluorescein angiography (FA) is primarily used to evaluate:
Answer: Retinal and choroidal vasculature
Fluorescein angiography involves IV injection of fluorescein dye to visualize retinal and choroidal circulation, detecting leakage, blockage, and neovascularization.
Which visual field defect is associated with a pituitary adenoma compressing the optic chiasm?
Answer: Bitemporal hemianopia
Pituitary adenomas compress the crossing nasal fibers at the optic chiasm, causing bitemporal hemianopia (loss of both temporal fields).
A-scan ultrasonography in ophthalmology is primarily used for:
Answer: Measuring axial length for IOL calculations
A-scan ultrasonography measures the axial length of the eye, which is essential for calculating intraocular lens (IOL) power before cataract surgery.
Corneal topography measures which property of the cornea?
Answer: Curvature across the corneal surface
Corneal topography (videokeratography) maps the curvature of the anterior corneal surface using Placido disc reflection patterns or Scheimpflug imaging.