nägemisväljade

Nägemisväljad (English: fields of view) refer to the visual area that an individual can see around their focus without turning the head or eyes. In a normal human eye, each side holds about 90° of the visual perceivable space, giving a total horizontal field of approximately 180°. The vertical field is about 60° upward and downwards. The combined binocular field includes overlap central vision (about 30°–40°) and a perifoveal region that provides peripheral awareness. Visual field measurements are essential in diagnosing and monitoring various ocular and neurological disorders, such as glaucoma, optic neuritis, cranial nerve damage, and brain lesions.

Clinically, visual field testing is performed using perimetry. Automated static perimeters (e.g., Humphrey Field Analyzer) chart sensitivity across a grid of test points to map areas of loss or depression in the field. Dynamic perimetry, by contrast, detects the minimum luminous intensity required for a moving target to be seen. Both methods are noninvasive and provide objective data about retinal sensitivity, optic nerve function, and cortical processing. In addition, infrared pupillometry and virtual reality perimetry are emerging technologies that offer higher resolution and patient comfort.

Preserving the integrity of the visual field is vital for everyday functioning. Loss in the peripheral field may impair motion detection, balance, and navigation, while central field deficits can cause difficulties with reading, face recognition, and precise hand movements. Rehabilitation strategies, such as compensatory eye movement training and visual aids, aim to mitigate the functional impact. Understanding and monitoring nägemisväljad, therefore, plays a crucial role in maintaining visual health and quality of life.