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Visual Field: Field Protocol Date of SC final approval About the Measure Domain: Ocular (included in Survey & Supplemental Information) Measure: Visual Field: Field Protocol (included in Survey & Supplemental Information) Definition: (included in Survey & Supplemental Information) Purpose: Measurement of an individual's vision field (central and peripheral vision) will be tested with Frequency Doubling Technology (FDT) using the Humphrey Matrix perimetry instrument. Visual field testing is used to detect defects in the visual pathway which extends from the tear film that coats the cornea to the occipital cortex. About the Protocol Description of Protocol: (included in Survey & Supplemental Information) Selection Rationale: Specific Instructions: Protocol text: (included in Survey & Supplemental Information) Visual field testing is performed on each eye of the participant using the FullThreshold N-30 (N-30-F) and the 24-2 Threshold procedures on the Humphrey Matrix Frequency Doubling Technology (FDT) visual field instrument (Carl Zeiss Meditec, Inc., Dublin, CA). The Frequency Doubling Technology (FDT) instrument uses a frequency doubled stimulus designed to specifically target a subset of retinal ganglion cells called M-cells but defects in other parts of the visual pathway will also yield abnormalities on this test. The FDT instrument is a table top instrument weighing only 19 lbs that requires little patient set-up, no eye patch or special trial lens for testing. Its ability to screen for glaucoma in the ophthalmology clinic setting is well documented. The FDT instrument costs considerably less than the Humphrey Automated Field Analyzer (HVFA) ($6,500 versus $29,000 in February 2010) but the instrument itself does not store raw data that is generated which must either be downloaded to another computer as a .PDF file or to hard copy. The FDT instrument is a desirable, inexpensive and less technicianintensive alternative instrument for assessing the visual field that may be suitable for some purposes, especially for glaucoma screening in a non-ophthalmic setting. None Subjects will have two Frequency Doubling Technology (FDT) tests using the Humphrey Matrix, the Full-Threshold N-30 (N-30-F) and the 24-2 Threshold procedures performed on each eye. To perform both the N-30-F and 24-2 tests, it is essential that you have a Humphrey Matrix and not an original FDT instrument. The tests should be administered using the Subject’s normal distance correction (glasses or contact lenses). Eyeglasses with bifocal corrections can be used. ENTERING SUBJECT DATA Version 9 – 8/10/09 Visual Field: Field Protocol Date of SC final approval 1. The MAIN MENU can be accessed by pressing the F1 button located at the upper right corner of the Humphrey Matrix Screen. 2. From the MAIN MENU of the HUMPHREY MATRIX, select N-30-F FDT Threshold or 24-2 FDT Threshold under the Threshold menu by pressing this location on the screen. 3. After this selection, you will be taken to the “View Patients” screen. Select “Add New Patient” by pressing this button at the top left portion of the screen and enter in the subject ID and date of birth, other information. After this select “Add Patient” by pressing the button in the lower right portion of the screen. 4. Enter the Pupil Diameter, Visual Acuity, and Rx as described in the table below. FDT Screen: Pupil Diameter Information Entered: RE: e.g., 4 mm LE: Visual Acuity RE: e,g,, 20/20 LE: Rx Used RE: 1(+ or -) _.__ DS (+ or -) _.__DC X ___DEG LE: (+ or -) _.__ DS (+ or -) _.__DC X ___DEG 1 Enter 3 digits for each, 0.00 for plano. “Rx Used” is the correction that is used for performing visual field testing. 5. The Operator LCD Display will indicate if there is too much ambient light to perform a reliable test. Lower the room lighting or change the test location until suitable test conditions are achieved. Also, if the subject response button is not connected or the subject visor is in the wrong eye position, this will be indicated on the operator LCD display. PREPARING THE SUBJECT For the eye being tested, if the brow is heavy or the upper lid is drooping, tape it accordingly. When in doubt, tape the upper lid. Slide the subject visor to the study eye test position and ask the Subject to place their forehead on the forehead rest and look into the subject eyepiece at the video screen. Adjust the height of the chair or table (or both) to obtain a comfortable position for the Subject. Confirm that the Subject can see the entire lit video screen, including all four corners in the subject eyepiece, establish that they can see the black dot in the middle of the screen and that their eye is centered on the video screen. Make sure that the Subject is properly aligned with the instrument by asking him/her to look to each of the four corners of the display to make sure that the display is not obscured. Select the “Freeze” button to freeze the live image of the eye to measure the Subject’s pupil diameter. Measure the Subject’s pupils to the nearest 0.5 mm. If they are less than 3 mm in diameter, dilate them with 2.5% phenylephrine drops, unless contraindicated. If this is ineffective, dilate with a cycloplegic agent and wait a full 20 minutes before beginning the test. If a Subject’s pupil is < 3 mm with cycloplegia, he/she is ineligible for visual field testing and cannot be enrolled in the study. After measuring the Subject’s pupil diameter, press the “Unfreeze” button to return to a live video of the Subject’s eye. Version 9 – 8/10/09 Visual Field: Field Protocol Date of SC final approval FDT N-30-F and 24-2 SUBJECT INSTRUCTIONS Read the Subject the following instructions: “A demonstration of the test is running now. Can you see the black square (dot) in the center and the entire lit video screen? You need to stare at the black dot in the center of the screen during the entire test.” “From time to time, you will see patterns of flickering black and white vertical bars that will briefly appear in different areas of the screen. The pattern will sometimes be very faint and at other times be very distinct. You are not expected to see the bar patterns at all times. Each time you see something flickering, press the response button once. Can you see these patterns in the demonstration running now? You may practice now by pressing the button to respond to the patterns.” “It is OK to blink, a good time to blink is when you press the response button. If you need to rest or ask questions during the test, you can pause the test at any time by pressing and holding down the response button. Do you have any questions? Do you understand how to take the test?” “I will now start the test. There will be a few brief flashes and then the test will begin. Press the response button once each time you see something flickering. Please remember to stare at the black square (dot) in the center of the screen during the entire test.” During the test, you will see the Subject’s pupil in the black box below. Keep an eye on the Subject’s pupil to make sure that they are maintaining fixation on the black dot in the center of the screen and that the pupil is inside the circle in the black box. Notes concerning the test can be added to the “Notes” box. Participant: SAVING & PRINTING THE FDT RESULTS Save a CSV and PDF version of the Subject’s data. Print out the test results at the completion of each test. Adults ≥ 18 years (included in Survey & Supplemental Information) Source: (included in Survey & Supplemental Information) Language of Source: Visual Field Reading Center, Department of Ophthalmology & Visual Science, University of Iowa Hospitals & Clinics Standard Automated Perimetry (SAP), Humphrey Matrix & Frequency Doubling Technology (FTD) Visual Field Guidelines, Version date 9/9/09. English Version 9 – 8/10/09 Visual Field: Field Protocol Personnel and Training Required: Date of SC final approval Trained ophthalmic technician or ophthalmologist (included in Supplemental Information) Equipment Needs: (included in Supplemental Information) Humphrey Matrix Frequency Doubling Technology (FDT) visual field instrument. (Carl Zeiss Meditec, Inc., Dublin, CA) Note: This protocol for visual field uses the Humphrey Matrix Frequency Doubling Technology (FDT) visual field instrument. If other instruments are used, the reproducibility of the measurements should be comparable to those acquired with this protocol. In addition, when other instruments are used to collect these measurements, the manufacturer and model of equipment should be recorded. These other devices may require some different steps than are described in this protocol. Investigators should follow the equipment manufacturer’s instructions to ensure quality control. Protocol Type: Clinical measurement Requirements: Common Data Element (CDE): General References: Requirements Category Required Major equipment Yes Specialized training Yes Specialized requirements for biospecimen No collection Average time of greater than 15 minutes in an No unaffected individual To be completed later None (included in Supplemental Information) Protocol ID: To be completed later Additional Information About the Measure Essential Data: None Version 9 – 8/10/09 Visual Field: Field Protocol Related PhenX Measures: None Derived Variables: None Keywords / Related Concepts: Ocular, Eye, Visual field, Peripheral vision Collections / Used By: To be completed later Measure ID: To be completed later Date of SC final approval Version 9 – 8/10/09