Chapter 10: Adjunctive Tests and Procedures

Question 1

4 Principle Categories of Testing

Answer 1

1) Assessments of potential visual acuity and functional vision in patients with Media Opacities
2) Tests for Corneal Structure and Disease
3) Photography of the external eye and fundus
4) Ultrasonography

Question 2

Ocular Media

Answer 2

The transparent optical structures that transmit light: cornea, aqueous, lens and vitreous.

Question 3

Media Opacities

Answer 3

The general term used to describe a variety of conditions that cloud, obscure, or otherwise affect the ocular media and, ultimately, may disrupt vision.
Most common are the ones that affect the lens (cataracts) and cornea (edema and scarring)

Question 4

Visual Potential Tests

Answer 4

1) Potential Acuity Meter
2) Occluder and Pinhole
3) Interferometer
4) Retinal Acuity Meter

Question 5

Potential Acuity Meter (PAM)

Answer 5

A device for determining visual acuity in the presence of media opacities. The device projects a brightly lit, miniature Snellen Chart through the least dense area of opacity.

Question 6

Occluder and Pinhole

Answer 6

Pinhole testing can help determine macular function. A dilated patient holds an opaque disc with holes at a near acuity chart

Question 7

Interferometer

Answer 7

A device that uses laser or other special light beams to determine visual acuity in the presence of an opacity

Question 8

Retinal Acuity Meter

Answer 8

A handheld, battery-powered device that consists of a brightly illuminated near card with Snelllen letters. This test measures the retinal acuity.

Question 9

Contrast-Sensitivity and Glare Tests

Answer 9

Part of the eye’s ability to see is the ability to perceive a difference between light and dark, which is called contrast sensitivity.

Question 10

Contrast-Sensitivity Test

Answer 10

A procedure for determining the ability to distinguish between light and dark areas
Can be useful for diagnosing a cataracts, optic neuropathies and retinal disease

Question 11

Glare

Answer 11

A scattering of a single bright light source upon a visual field that interferes with one’s sight and markedly reduces that quality of the image received by the retina

Question 12

Glare Testing

Answer 12

A procedure for assessing a patient’s vision in the presence of a bright light source to determine whether sensitivity to glare is contributing to visual symptoms

Question 13

Brightness Acuity Tester

Answer 13

A handheld instrument used to assess the disability that occurs when glare interferes with a patient’s visual acuity or quality of vision

Question 14

Assessment of Corneal Abnormalities

Answer 14

1) Pachymetry
2) Corneal Topography
3) Specular Microscopy/Photography 4)

Question 15

Pachymetry

Answer 15

The measurement of corneal thickness by the use of a pachymeter
Used for evaluation of glaucoma, keratoconus, cataract surgery, other corneal conditions

Question 16

Optical Pachymeter

Answer 16

A device for measuring the thickness of the cornea using an optical system

Question 17

Ultrasonic Pachymeter

Answer 17

An instrument that measures corneal thickness, the distance between corneal epithelium and endothelium by an ultrasonic probe

Question 18

Corneal Topography

Answer 18

A device that records the surface terrain of the cornea, used to detect aberrations of the contour, as well as regular and irregular astigmatism.
This measurement is used a lot in the evaluations of refractive surgeries (LASIK, PRK), as well as corneal disorders and cornea transplants.
EX: Pentacam

Question 19

Specular Microscopy/Photography

Answer 19

A method of microscopically photographing the cornea’s endothelial cells at great magnification and producing photographs on which the cells can be counted

Question 20

Ophthalmic Photography Types

Answer 20

1) External photography- aids in documenting abnormalities of the adnexa
2) Slit lamp photography- used in documenting abnormalities of cornea, angles, iris and lens
3) Fundus photography- used in documenting abnormalities of the fundus

Question 21

Fundus Camera

Answer 21

A large ophthalmoscope that can produce color images of the retina and optic nerve
EX: Fluorescein angiography

Question 22

Tomography

Answer 22

A detailed mapping of the contours of a tissue or organ

Question 23

Optical Coherence Tomography

Answer 23

A system used for analysis of the optic nerve head and retinal nerve fiber layers, as well as the macular tissue layers by producing topographic images
Machine includes a light source, a light detector, beam splitter, and a moveable mirror

Question 24

Ultrasonography

Answer 24

A method of examination that uses the reflection of high-frequency sounds waves to define the outline of ocular and orbital structures, measure the distance between structures, and identify abnormal tissues inside the eye or orbit
Also called Biometry
Sometimes used when OCT is not an option due to opacity within the eye (dense cataracts)

Question 25

A-scan Ultrasonography

Answer 25

A diagnostic procedure in which sound waves traveling in a straight line are used to reveal the position of, and distances between, structures within the eye and orbit.
Typically between 23 and 25 mm
Needed for Cataract Evaluation for lens choice (inaccuracy by 1mm can lead to a 3D difference in vision)

Question 26

Oscilloscope

Answer 26

An instrument box with a TV-like screen that displays the shape of an electric current or ultrasonic current wave as seen with ultrasonography

Question 27

B-scan Ultrasonography

Answer 27

A diagnostic procedure that provides 2D reconstruction of ocular and orbital tissues, using radiating sounds waves