Search results
Results From The WOW.Com Content Network
Taking visual field test using a Goldmann perimeter. ICD-9-CM: 95.05: MeSH: MedlinePlus: LOINC: 28629-4: A visual field test is an eye examination that can detect ...
The visual field index (VFI) reflects retinal ganglion cell loss and function, as a percentage, with central points weighted more. [21] It is expressed as a percentage of visual function; with 100% being a perfect age-adjusted visual field and 0% represents a perimetrically blind field.
Goldmann applanation tonometry (GAT) is considered to be the gold standard IOP test and is the most widely accepted method. [4] [5] A special disinfected prism is mounted on the tonometer head and then placed against the cornea. The examiner then uses a cobalt blue filter to view two green semicircles.
Testing the visual fields consists of confrontation field testing in which each eye is tested separately to assess the extent of the peripheral field. Normal visual field of a right eye. To perform the test, the individual occludes one eye while fixated on the examiner's eye with the non-occluded eye.
Theoretically, average corneal rigidity (taken as 520 μm for GAT) and the capillary attraction of the tear meniscus cancel each other out when the flattened area has the 3.06 mm diameter contact surface of the Goldmann prism, which is applied to the cornea using the Goldmann tonometer with a measurable amount of force from which the IOP is ...
The visual field is "that portion of space in which objects are visible at the same moment during steady fixation of the gaze in one direction"; [1] in ophthalmology and neurology the emphasis is mostly on the structure inside the visual field and it is then considered “the field of functional capacity obtained and recorded by means of perimetry”.
Ocular hypertension (OHT) is defined by intraocular pressure being higher than normal, in the absence of optic nerve damage or visual field loss. [13] [14] Ocular hypotension, hypotony, or ocular hypotony, is typically defined as intraocular pressure equal to or less than 5 mmHg.
The meridian of the visual field has been found to influence the folding of the cerebral cortex. In both the V1 and V2 areas of macaques and humans the vertical meridian of their visual field tends to be represented on the cerebral cortex's convex gyri folds whereas the horizontal meridian is tends to be represented in their concave sulci folds ...