Goldmann Visual Field. Humphrey Visual Field 4/25/2017. What s So Special About Special Testing?! Houston, we have a problem.

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Bridget Wilkerson
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What s So Special About Special Testing?! Why can t they get the schedule right? looneytunes.

We all assume that the other people in the office know what we do, how we do it, and what we need in order

Goldmann Visual Field (GVF) wikipedia.com killinglyeyecare.com Goldmann Visual Field Tech is the machine.

Kinetic (moving) is used to determine the boundaries of the visual field (isopters).

1 What s So Special About Special Testing?! Why can t they get the schedule right? looneytunes.com Houston, we have a problem. Communication is the key. We all assume that the other people in the office know what we do, how we do it, and what we need in order for us to do it. So, what is it we do when we do what we do? Humphrey Visual Field (HVF) vs. Goldmann Visual Field (GVF) wikipedia.com killinglyeyecare.com Goldmann Visual Field Tech is the machine. this perimeter allows us to perform kinetic as well as static perimetry. Kinetic (moving) is used to determine the boundaries of the visual field (isopters). Static (still) is used inside of a boundary to determine the sensitivity in a given area to a given stimulus (light). Humphrey Visual Field The perimeter performs static testing to determine the sensitivity of a stimulus in a given area. Humphrey visual fields are usually a shorter testing process that can determine the earliest visual field changes. It will adjust light thresholds and the size of the light depending on the patient responses. 1

With Goldmann, the tech draws what the patient sees or does not see.

It also analyzes and compares that information with past results. sciencedirect.

losses, pause test, re-instruct patient, ensure patch is on appropriately. Resume test.

IF another loss - consider discuss with MD if wish to continue!

Dilated: Maximum amount of visual field potential that a patient has VA, TA, DILATE, GVF = 1 ½ hrs VA, TA,

Undilated: How a patient sees normally VA, TA, GVF = 40 minutes VA, TA, HVF = 20 minutes Dilated or Undilated?

2 With Goldmann, the tech draws what the patient sees or does not see. With the HVF, the machine documents the degree (size & intensity) of the of the stimulation that the patient sees. It also analyzes and compares that information with past results. sciencedirect.com Technician Role During Test Monitor fixation Keep patient motivated IF there are more than (3) fixation losses, pause test, re-instruct patient, ensure patch is on appropriately. Resume test. If there is another fixation loss, pause test and change fixation parameter to I4e. Resume test. IF another loss - consider discuss with MD if wish to continue! Dilated Or Undilated: It s What Your Doctor Prefers! Dilated or Undilated: a. Dilated: Maximum amount of visual field potential that a patient has VA, TA, DILATE, GVF = 1 ½ hrs VA, TA, DILATE, HVF = 1 hour b. Undilated: How a patient sees normally VA, TA, GVF = 40 minutes VA, TA, HVF = 20 minutes Dilated or Undilated? Dilated : All patients get a added to their sphere of their correction regardless of age Undilated: Use the add for age chart added to their sphere Astigmatism: Use the astigmatism chart whether they are dilated or undilated 30 to to to to to and over Add For Age This add is added to the sphere of the Rx. Perimetry 2 nd edition Anderson 2

Cylinder bhryyxn Pachymetry Cylinder Visual Field Correction +0.25 none +0.50,+ 0.75 +0.25 added to sphere +1.

A central corneal thickness < than 555µm should be viewed as a risk factor for the development of glaucoma Intraocular Pressure may be UNDERESTIMATED

org Pachymetry in Diagnosis of Glaucoma Considerations Glaucoma Risk Thick cornea / Nl TA ------ Thick cornea / TA + Thin cornea / Nl TA +/- Thin

map of the cornea. Shades of blue and green represent flatter areas of the cornea, whereas reds and oranges represent steeper areas. doctor-hill.

3 Cylinder bhryyxn Pachymetry Cylinder Visual Field Correction none +0.50, added to sphere or more keep it all Perimetry 2nd edition Anderson Measures corneal thickness. A central corneal thickness < than 555µm should be viewed as a risk factor for the development of glaucoma Intraocular Pressure may be UNDERESTIMATED if you have thin corneas and it may be OVERESTIMATED if you have thicker corneas. medrounds.org Pachymetry in Diagnosis of Glaucoma Considerations Glaucoma Risk Thick cornea / Nl TA Thick cornea / TA + Thin cornea / Nl TA +/- Thin cornea / TA Average cornea / Nl TA Average cornea / TA ++ * Average cornea thickness 555 microns Topography Topography is a contour map of the cornea. Shades of blue and green represent flatter areas of the cornea, whereas reds and oranges represent steeper areas. doctor-hill.com Corneal Mapping or Videokeratography A virtual image of the cornea occurs due to 8,000 10,000 evaluation points that are plotted. Keratometers only measure the cornea s central 3-4 mm! Axial map: sagittal or power map. Shows variations in curvature. Projections and colors are represented in diopter power values. Axial Map 3

Tangential Map Axial maps determine the radius of curvature of the cornea at each measured point.

It shows variations in corneal curvature as projections and uses colors to represent dioptric

Warm colors such as red and orange show steeper areas; cool colors such as blue and green denote

True map does same as axial, but uses a different mathematical formula to determine the

Displays the cornea as a topographical picture, using colors to represent changes in dioptric

$This display is most useful in following trends in the postsurgical or pathologic eye Refractive$ $Map Uses dioptric power and Snell s law to determine the refractive power of the cornea.$ $A refractive map compensates for spherical aberrations as well as the aspheric contour of the$ This area overlies the pupil, so aberrations here may impact vision.

This area overlies the pupil, so aberrations here may impact vision.

4 Tangential Map Axial maps determine the radius of curvature of the cornea at each measured point. It gives the simplest of all the topographical displays. It shows variations in corneal curvature as projections and uses colors to represent dioptric values. Warm colors such as red and orange show steeper areas; cool colors such as blue and green denote the flatter areas. True map does same as axial, but uses a different mathematical formula to determine the peripheral cornea. Displays the cornea as a topographical picture, using colors to represent changes in dioptric value. It does not assume the eye is spherical. Tangential maps also offer a better visualization of the precise location of corneal defects. This display is most useful in following trends in the postsurgical or pathologic eye Refractive Map Uses dioptric power and Snell s law to determine the refractive power of the cornea. Central portion most important. Used mostly with post PRK or LASIK patients. A refractive map compensates for spherical aberrations as well as the aspheric contour of the cornea. The central portion of the refractive map is most important. This area overlies the pupil, so aberrations here may impact vision. Keratometer Also known as an ophthalmometer, is a diagnostic instrument for measuring the curvature of the anterior surface of the cornea x x x 180 anatomical astigmatism doctor-hill.com Considerations Ideally, patient should not have a procedure such as tonometry or gonioscopy performed on them prior to having the topography to ensure that the cornea is not disturbed. Photography: Slit Lamp Takes pictures of the lids, anterior chamber and front surface of the lens. No dilation needed. eyeworld.com eyerounds.org 4

both eyes as well as a part of the face.

5 Photography: External Photography: Fundus A facial camera shot of one or both eyes as well as a part of the face. Patient can be identified by this photo so be careful of HIPAA! Photography of the posterior part of the eye from the vitreous back to the optic nerve. Pupil must be dilated. firmoo.com meded.ucsd.edu bethesdaretina.com retinagallery.com Photography: Angiography Fluorescein dye is injected into the patient s arm, and then sequential fundus photography is performed using different camera filters. FUNDUS PHOTOGRAPHY! OCT (Ocular Coherent Tomography) Cystoid Macular Edema Normal Retina Anatomy eyetumour.co.uk crivereureka.com Normal Retinal Anatomy A thin, coherent beam of light shows two and three dimensional images of macula, fovea and retina areas. Also the optic nerve. High resolution of tissue cross section. eye-injections.com eyetumour.co.uk 5

posterior segment. It was introduced in 1993 specifically for ophthalmology and has now morphed to Dermatology and other areas of the body.

What that means is that it is very similar to Sound ultrasound technology in the theory of measuring the distance between reflections of either sound or

Light The OCT uses light waves whereas the A Scan uses sound waves (10 mgh) 0aGFuIHR Time Domain Time domain OCT (TD OCT): Uses an interferometer that

from the reference mirror at specific distances. The most widely used system is the Stratus OCT 3 (Carl Zeiss Meditec, Inc.). ophthalmologymanagement.

com Volume measurement covers a 6 mm diameter circle, but thickness data is only available from (6) evenly spaced radial lines in a circle.

Spectral Domain Spectral domain OCT: The reference mirror is stationary so the scanning process occurs quicker.

6 What Is It? Optical Coherence Tomography Is a 3D, non invasive imaging system using a beam of low coherence light to evaluate the health of the optic nerve and posterior segment. It was introduced in 1993 specifically for ophthalmology and has now morphed to Dermatology and other areas of the body. It is based on "white light interferometry which provides excellent depth resolution. What that means is that it is very similar to Sound ultrasound technology in the theory of measuring the distance between reflections of either sound or light. Light The OCT uses light waves whereas the A Scan uses sound waves (10 mgh) 0aGFuIHR Time Domain Time domain OCT (TD OCT): Uses an interferometer that measures the time it takes for light to be reflected back from retinal structures and then compares it to the time it takes for light to be reflected back from the reference mirror at specific distances. The most widely used system is the Stratus OCT 3 (Carl Zeiss Meditec, Inc.). ophthalmologymanagement.com Interpolated data: when you are doing a retinal map analysis, interpolation constructs new data points from a set of known data. rethinkhr.com Volume measurement covers a 6 mm diameter circle, but thickness data is only available from (6) evenly spaced radial lines in a circle. This means the space between the lines is interpolated : not real data but estimated on what might be there if there were a number actually assigned there! Spectral Domain Spectral domain OCT: The reference mirror is stationary so the scanning process occurs quicker. Interprets the whole coherent wavelength of the various layers of tissue enabling us to see layer thicknesses using 3D axial slices. ophthalmologymanagement.com *SD-OCT images a larger area of the retina faster than time domain, so eye movement is less of an issue and the retinal map is more accurate to determine treatment response *Gives a larger set of actual data points allowing for accurate spatial correlations and mapping of individual retinal layers over a larger area in a shorter period of time. Cirrus OCT (Carl Zeiss Meditec, Inc.) and Spectralis HRA+OCT (Heidelberg Engineering, Inc) are some examples. retinavitreous.com 6

A-scan: IOLMASTER Laser beam is used to determine the axial length. Non contact ability gives the most accurate axial length reading because the cornea is not indented.

Amplitudes, height of the spike echos B-Scan: (2) dimensional.

sound beam to travel it is possible to calculate distance sound has traveled doctor-hill.com A-Scan Biometry Must measure on axis in order to obtain correct measurement.

7 A-scan: IOLMASTER Laser beam is used to determine the axial length. Non contact ability gives the most accurate axial length reading because the cornea is not indented. Patients may be dilated for this exam. Keratometry will also be performed. A-Scan Biometry Echography: uses high frequency sound waves (10 MHz) A-Scan: (1) dimensional. Amplitudes, height of the spike echos B-Scan: (2) dimensional. Shows topography Biometry measures the distance between structures Axial Length: What is length of average eye, myopic eye, hyperopic eye Knowing the sound velocity and the time required for the sound beam to travel it is possible to calculate distance sound has traveled doctor-hill.com A-Scan Biometry Must measure on axis in order to obtain correct measurement. Be careful not to compress the cornea! Will it make length shorter or longer? What do the spikes mean? a. initial spike (probe tip at contact) b. anterior lens c. posterior lens d. retina spike e. sclera f. orbital fat A-Scan Biometry Color Vision Testing Contact Method (Applanation ): Probe touches cornea. Careful with indentation! Gives mm shorter reading! Non-Contact Method: A. Sleeve filled with methylcellulose or saline & placed on the eye. Probe immersed in fluid. B. IOLMASTER: laser Physiology of Color : red cones (erythrolabe) are long, green cones (chlorolabe) are medium, blue cones (cyanolabe) are short. anopia = inability to detect color anomaly = decrease in ability to detect a particular color * Protanomaly: poor red/green with red appearing dim * Deuteranomaly: poor red/green with red appearing normal * Tritanomaly: poor blue/green and blue/yellow Spikes different in all (3) methods! revophth.com 7

Color Vision Testing: Inherited Color Defects Trichromats have normal color vision. All (3) cones pigments.

The test consists of a number of colored plates containing a circle of dots randomized in color and size within the randomized pattern are

vision defect. The full test consists of thirty-eight plates, but the existence of a deficiency is usually clear after a few plates.

Generally, not good for acquired. Normal result is at least 11 of 14 plates correct. One eye at time, with correction.

org D-15 Color Vision Test (subset of Farnsworth 100) The Farnsworth D-15 Color Vision Test is designed to correctly identify all (congenital

8 Color Vision Testing: Inherited Color Defects Trichromats have normal color vision. All (3) cones pigments. Dichromats have only (2) functioning pigments. Monochromats have (1) pigment Color Vision A test for red-green color defects. The test consists of a number of colored plates containing a circle of dots randomized in color and size within the randomized pattern are dots which form a number visible to those with normal color vision and invisible, or difficult to see, for those with a red-green color vision defect. The full test consists of thirty-eight plates, but the existence of a deficiency is usually clear after a few plates. psychology.ucalgary.ca Color Vision Testing: Ishihara Plates Pseudoisochromatic plates Tests for red-green congenital defects. Generally, not good for acquired. Normal result is at least 11 of 14 plates correct. One eye at time, with correction. One eye at a time Best corrected vision Record which plates the patient misses Do not touch the book with your fingers! en.wikipedia.org D-15 Color Vision Test (subset of Farnsworth 100) The Farnsworth D-15 Color Vision Test is designed to correctly identify all (congenital and acquired) color deficiencies, no matter how slight. A score sheet is enclosed to represent the order of the patient s arrangement of the caps, with respect to their correct sequence around the color circle. Arranges caps by HUE. good-lite.com 8

Vertex Distance Vertex Distance Rule of thumb: Anyone : +4.00 or more

00 or more to maintain the effective power of the lens opticianshandbook.

This allows you to test the vision without interference from a cataract. For the Super Pinhole, the patient looks at a special chart through a disc with tiny holes.

The Potential Acuity Meter (PAM) focuses a single beam of light in the pupil and a letter chart onto the retina.

Assess acuity in a cataract, or other opacity, as the beams provide an estimate of the visual acuity.

9 Vertex Distance Vertex Distance Rule of thumb: Anyone : or more or or more!!! Distance in millimeters from the back surface of the lens to the front surface of the cornea measured with a distometer Used in Rx of +/ or more to maintain the effective power of the lens opticianshandbook.com PAM (Potential Acuity Meter) The PAM projects the eye chart directly on the retina and bypasses a cataract. This allows you to test the vision without interference from a cataract. For the Super Pinhole, the patient looks at a special chart through a disc with tiny holes. This allows the patient to isolate clear spots in the cataract. The Potential Acuity Meter (PAM) focuses a single beam of light in the pupil and a letter chart onto the retina. Interferometer Designed to measure visual acuity by using narrow beams of light focused within the pupil. Assess acuity in a cataract, or other opacity, as the beams provide an estimate of the visual acuity. Example: Lotmar Visometer which is referred to as a clinical interferometer. Penetrates dense cataracts better than a PAM. BAT (Glare Testing ) The BAT (Brightness Acuity Tester) can simulate three bright light conditions: 1) High (direct overhead sunlight) 2) Medium (partly cloudy day) 3) Low (bright overhead commercial lighting) To Perform Make sure the BAT is turned OFF before you begin. Using the BAT with the switch set to OFF, measure the patient s vision in the standard manner with the best correction Turn the BAT to the LOW position. Test and record the visual acuity at this level. Repeat MEDIUM and HIGH. Do not perform the test through a phoropter!!!! thecartoonpapers.com 9

Amsler Grid Schirmer Tests A test of the central 20 degrees of the visual field.

Patient is asked to assess any distortion of lines, blank spots, etc.

Schirmer s Test I: uses the filter strip (3mm x 20mm) to measure the reflex tearing.

Schirmer s Test II uses topical anesthetic to measure baseline function and usually results in showing

10 Amsler Grid Schirmer Tests A test of the central 20 degrees of the visual field. Useful to monitor macular disease. Done one eye at a time with correction. Patient is asked to assess any distortion of lines, blank spots, etc. Boxes are 5mm in size and subtend an angle of 1 at 30 cm. Schirmer s Test I: uses the filter strip (3mm x 20mm) to measure the reflex tearing. No anesthetic is used, strip in eye x 5 minutes. Normal is 10 mm or more. Schirmer s Test II uses topical anesthetic to measure baseline function and usually results in showing less of the strip wetting. Other Tear Assessment Tests WAHOO!!!!!!!!!! BUT Test TBUT of less than 10 is significant for dry eye Schirmer Test 1.Normal 15 mm after Mild 14-9 mm after Moderate 8-4 mm after Severe <4 mm after 5. revoptom.com dgraves@stpauleye.com 10

Technicians & Nurses Program

ASCRS ASOA Symposium & Congress Technicians & Nurses Program May 6-10, 2016 New Orleans ADVANCED BIOMETRY AND IOL CALCULATIONS Financial Disclosures No relevant disclosures Karen Bachman, COMT, ROUB The