Imaging and Perimetry Society standards and guidelines.

PURPOSE: To provide readers with standards, recommendations, guidelines, and requirements for the application of perimetry to clinical ophthalmic practice and scientific study. METHODS: A working group of perimetry and visual field specialists from many parts of the world constructed a document that would allow current and future perimeters to be assessed by the same criteria. Because hardware and software technology, statistical procedures and clinical conditions are constantly changing, the characteristics in this paper emphasize general concepts rather than specific implementations employed by current devices. RESULTS: Critical aspects of perimetry included indications for perimetry, perimetric techniques, stimulus characteristics, test administration, patient preparation, data display, statistical analysis, interpretation of visual field findings, a glossary of terms and definitions, and standards for comparison of different perimetric tests. Each of these topics is discussed, along with their advantages and disadvantages. CONCLUSIONS: These guidelines serve as a basis for practitioners to evaluate their perimetric needs in relation to their clinical practice and patient population so that informed decisions can be made for visual field testing. In addition, these issues should be used as a cornerstone for future technological and practical improvements to the visual field diagnostic procedures.

Reaction test for competence in visual pathway lesions.

Performance in the visual environment was evaluated with a central fixation or a search target in 11 positions within 34 degrees on a CRT, superimposed on a landscape. Reaction times were recorded. We examined 24 patients aged 26-83, with lesions of the visual pathways and homonymous visual field defects, and 18 normal subjects aged 23-79. This simple test takes about 1 minute in normal subjects and four or more minutes in neurological patients. The test may be used to quantify saccadic adaptation to disability from homonymous field defects and to monitor the training effects of visual rehabilitation.

The visual performance test: indications for compensational visual rehabilitation training and first results.

The visual performance test (Dannheim & Verlohr, 2007) measures the time required to find an object within the visual field. Black icons of high contrast are superimposed on a scenic background of low contrast in one of 11 positions in random order. The subject's task is to find the search icon on the CRT screen as rapidly as possible. This test was administered binocularly in 38 patients with homonymous visual field defects. The aim of the test was to identify those patients who had not adapted themselves to their visual handicap, and to quantify the effect, in these patients, of training of compensational search saccades (Meienberg et al., 1981; Nelles et al., 2001; Trauzettel-Klosinski, 2004). The results show that the visual performance test reflects the practical abilities of these patients and that it may monitor the benefit of visual rehabilitation training in patients with functional restrictions in daily life.