Comparison of central and peripheral visual field properties in the optic neuritis treatment trial.

PURPOSE: To compare the results of peripheral kinetic visual field testing and central static perimetry for patients enrolled in the Optic Neuritis Treatment Trial to determine (1) whether loss and recovery of visual field sensitivity in the far periphery was different from that observed in the central visual field and (2) whether the far peripheral visual field provided additional useful information that was not available in the central visual field results. METHODS: Both affected and fellow eyes of 448 patients with optic neuritis in the Optic Neuritis Treatment Trial were evaluated according to the trial protocol during the patients' first 3 years in the study. Central static visual field tests were performed with program 30-2 on the Humphrey Field Analyzer, and peripheral kinetic testing consisted of plotting the I3e and II4e isopters on the Goldmann perimeter. Both test procedures were conducted according to the trial protocols, and quality control assessments and clinical evaluations were performed on all the visual fields. RESULTS: For both affected and fellow eyes at all 11 visits, there was a greater number of abnormal visual fields in the central static perimetry results than in the peripheral kinetic data. Only 2.9% of affected eyes had an abnormal peripheral visual field with a normal Humphrey mean deviation during year 1. At baseline, 97.1% of affected eyes had an abnormal Humphrey mean deviation on central static testing, whereas only 69.9% had abnormal peripheral kinetic visual fields. Approximately 80% of the I3e and II4e isopters for affected eyes that were abnormal at baseline were within normal limits at 30 days, but it took until week 19 for even 70% of the Humphrey mean deviations to return to normal. In addition, the II4e isopters (more peripheral than the I3e isopters) that were abnormal at baseline showed a somewhat greater percentage of improvement from baseline through day 30 than the abnormal I3e isopters. Although this difference is statistically significant, it is probably not clinically significant. For visits after week 19, approximately 25% to 30% of affected eyes had an abnormal Humphrey mean deviation, whereas only 10% to 15% of peripheral kinetic fields were abnormal. CONCLUSIONS: For the affected eye in optic neuritis, the central visual field shows greater abnormalities than the far peripheral visual field. When the results obtained through Humphrey automated central static visual fields and Goldmann peripheral kinetic isopters are compared, the far periphery appears to recover more rapidly and more completely than the central field, at least in more severe cases of optic neuritis. In most cases, recovery in optic neuritis can probably be monitored effectively with automated perimetry of the central visual field alone. However, in cases of severe loss of the central visual field, a peripheral kinetic visual field obtained with a Goldmann perimeter may provide additional information about the patient's vision in the far periphery.

Visual field profile of optic neuritis. One-year follow-up in the Optic Neuritis Treatment Trial.

PURPOSE: The purpose of this present study was to evaluate longitudinal visual field information for 448 patients over their first year of follow-up in the Optic Neuritis Treatment Trial. METHODS: We reviewed 6536 automated static visual fields performed on a visual field analyzer (Humphrey Visual Field Analyzer) at nine visits within the 1-year period for each of the patients. RESULTS: The median values of the mean deviations for affected eyes were as follows: -22.88 dB at baseline, -1.94 dB at 6 months, and -1.62 dB at 1 year. At 6 months, 51% of affected eye visual fields were normal, and at 1 year 55.9% were normal. Approximately two thirds (68.8%) of the fellow eyes were classified as abnormal at baseline, although the defects were generally slight. One third (33.2%) were abnormal at 6 months, and approximately one third were still abnormal at 1 year. More than 87% of those abnormal at 6 months and at 1 year had been abnormal at baseline. Binocular analysis revealed that 13.2% of patients showed a chiasmal or retrochiasmal type of field defect at least once during the year (5.1% bitemporal; 8.9% homonymous). Of the patients who showed a retrochiasmal visual field defect, 75.7% had an abnormal magnetic resonance imaging scan at baseline compared with 46% of the rest of the patients in the Optic Neuritis Treatment Trial (chi 2 = 10.73, df = 1, P < .002). CONCLUSION: Over the first year of follow-up, the majority of patients with visual field defects from acute optic neuritis returned to normal, as measured by automated static perimetry. Many fields showed variation in the pattern and location of the sensitivity loss. Chiasmal and retrochiasmal defects occurred more commonly than previously reported.

Quality control functions of the Visual Field Reading Center (VFRC) for the Optic Neuritis Treatment Trial (ONTT).

The Visual Field Reading Center (VFRC) was established to assess visual field testing in the Optic Neuritis Treatment Trial (ONTT), to train and certify ONTT technicians, and to monitor the quality of the visual fields through evaluation of the technical aspects of the visual field testing. We describe the functions of the VFRC personnel and the standardized test protocols developed by the VFRC for Humphrey and Goldmann perimetry. We also describe the VFRC procedures for training and certifying visual field technicians, double-checking the eligibility of ONTT patients, assessing the quality of the visual field data, and processing visual field data. In addition, we describe the principles applied by the director and associate director of the VFRC in their clinical classification of the various localized and diffuse visual field defects observed in the Humphrey and Goldmann visual fields. The VFRC has processed more than 14,000 Humphrey and Goldmann visual field tests. The visual field quality control procedures and visual field defect classification process have been shown to be quite reproducible. Through quality control assessment procedures, we have been able to pinpoint a variety of problems at an early stage and promptly implement corrective measures. The standardized test protocols, technician training and certification procedures, and quality control assessment techniques used by the VFRC for the ONTT may serve as a model for future clinical trials employing visual field data as an outcome measure. These procedures can also be used to enhance visual field reliability in ophthalmological practices.

Baseline visual field profile of optic neuritis. The experience of the optic neuritis treatment trial. Optic Neuritis Study Group.

The purpose of the present study was to determine the baseline visual field characteristics in 448 patients with acute optic neuritis who were entered into the Optic Neuritis Treatment Trial. The severity and pattern of visual field loss in both the affected and fellow eyes were classified. For affected eyes, diffuse visual field loss was present in 48.2% of eyes, central or centrocecal scotoma was present in 8.3% of eyes, altitudinal or other nerve-fiber bundle-type defects were present in 20.1% of eyes, and a variety of other defects were present in 23.4% of eyes. Visual field involvement was present in the fellow eye at baseline in 308 (68.8%) of the 448 patients. Evidence of a chiasmal or retrochiasmal visual field defect was present in 2.9% of the patients. Since a wide variety of visual field defects can occur with an acute attack of optic neuritis, the pattern of visual field loss is of limited utility in distinguishing optic neuritis from ischemic optic neuropathy and other optic nerve disorders. Asymptomatic visual field defects in the fellow eye are common.