Optical/Surgical Device

Question 1

Slit Lamp

Answer 1

• biomicroscope
• examine external & anterior segments of eye (cornea, lens, fluids & membranes)
• also hold lens in front of eye to view posterior segment

Question 2

tonometer

Answer 2

• device to measure IOP

- diagnose glaucoma

Question 3

curette

Answer 3

• used for scrapping or debriding tissue

Question 4

hemostat

Answer 4

• clamp

Question 5

chalazion clamp

Answer 5

• two sided; one oval and other open ring

Question 6

lacrimal dilator

Answer 6

• small rod with pointed ends

- inserted into punctum to enlarge it

Question 7

lacrimal probe

Answer 7

• double ended

- inserted into punctum and through to nasolacrimal duct

Question 8

cannulas

Answer 8

• needle-like tube with blunt end
• fits on end of syringe
• inserted into punctum

Question 9

amsler grid

Answer 9

• black grid lines on white background (card #1)
• 7 different grids
• evaluates 10 degrees surrounding the centre of visual field (diameter of 20 degrees)

Question 10

Fundus Autofluorescence (FAF)

Answer 10

• lighting up of tissues when stimulated by a cobalt blue (UV) light
• no dye injected
• may see chemical byproducts of some disease processes ie) lipofuscin (fatty substance in retinal pigment epithelium)
• shows health of retina at cellular level

Question 11

Fluorescein Angiography (FA)

Answer 11

• inject fluorescein sodium (NaFI) to reveal blood flow in retinal vasculature
• uses blue exciter filter; green barrier filter

Question 12

Indocyanine Green Angiography

Answer 12

• injection of indocyanine green dye

- reveals blood flow in choroidal & retinal vasculature

Question 13

echography
ultrasonography
ophthalmic ultrasound

Answer 13

• visualize eye & orbit, tissue characteristics
• use high freq and short wavelength
• low energy (no harm to structures)
• A-scan, B-scan and optical biometry (most common)

Question 14

optical coherence tomography (OCT)

Answer 14

• uses nearinfrared light
• creates high-resolution cross-section imaging of retina
• 1) spectral domain - collects signals from 2mm depths of tissues simultaneously
• 2) time-domain - collects signals from 6 mm depths (iris and structures behind); less resolution
• most common: Heidelberg retina tomograph

Question 15

confocal scanning laser ophthalmoscopy (SLO)

Answer 15

• analyzes retinal nerve fibre layer & cupping of optic disc
• confirms glaucoma

Question 16

Humphrey Field Analyzer

Answer 16

• bowl shaped automated perimeter
• use full threshold, SITA std (swedish interactive thresholding algorithm), SITA fast to do statistical averages to evaluate visual field
• white target light briefly presented randomly in a range of 24 degrees central
• 24-2 SITA for glaucoma

Question 17

perimeter

Answer 17

• plots central or peripheral field of vision

Question 18

phoropter

Answer 18

• refraction device incorporating lenses, prism, occluders, pinholes to determine eye’s optical correction

Question 19

corneal topography

Answer 19

• analyze front surface of cornea or both front and back of cornea for thickness info
• displays blue for flattest curvature and red for steepest; green is “normal/average”
• for thickness, blue is thick and red is thin (red indicates pathology or previous surgery)

Question 20

optical biometry
(laser interference biometry)

Answer 20

• most common IOL Master and Lenstar
• measure corneal curvature, anterior chamber depth, lens thickness & axial length of eye
• need corneal stability prior to test

Question 21

Heidelberg retina tomograph (HRT)

Answer 21

• measures cup-to-disc ratio and compares to normal data
• used mainly for glaucoma
• as nerves die, the size of cup increases