This product was developed by Jeffrey Cooper, MS, OD, FAAO, Clinical Professor, SUNY State College of Optometry; evaluated and standardized by Sherry J. Bass, MS, OD, FAAO, Distinguished Teaching Professor, SUNY State College of Optometry."
The ACV instrument is a compact, black, rectangular instrument with a 1.0-mm red light-emitting diodes (LED) at each of its four corners and a fixation hole at the center. The device presents automated, randomized patterns of lit LEDs and the patient is asked to identify the number of lights seen. The eye care professional views the tested eye though the device to ensure fixation on the center and is able to validate the patient's response with the four indicators on the rear panel while the patient identifies the presentations of the random LED pattern on the front.
A controlled study that examined visual field testing methods at SUNY State College of Optometry indicated that the device has a greater sensitivity and is more accurate in the detection of moderate visual field loss than finger counting confrontation visual field tests. The study reported that screening with the ACV uncovered visual field loss by being able to detect smaller scotomas, which were missed in patients tested with finger counting confrontation. The study noted that other studies, which have utilized small red objects such as the LEDs used in the ACV, are more sensitive for the detection of both neurologic and glaucomatous field loss than finger or hand methods.
The ACV tester consists of a black unit measuring 12 cm by 17 cm. Four 1.0-mm red LEDs are positioned 11.25 cm apart, which results in an angular separation of 15° when the device is 60 cm from the patient. The tester is powered by an easily obtainable, 2 standard AA batteries. Reference: Bass, SJ, Cooper J, Feldman J, Horn D. Comparison of an automated confrontation-testing device vs. finger counting in the detection of field loss. Click here to read the study abstract