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What is Campimetry is used to measure: and explain in detail?
Campimetry (scotometry- it is useful to evaluate the central and paracentral area (30deg) of the visual field. For it, the Bjerrum's screen is used .(of either l metre or 2 metres square) Patient is seated at a distance of 1 metre for 1m Bjerrum Screen or 2 metres for 2m Bjerrum Screen The patient fixates at the central dot with one eye, the other being occluded. A white target (1-10 mm diameter) is brought in from the periphery towards the centre in various meridians. Initially the physiologic blind spot is chaed, any disooion / malalignment of blind spot from normal limits can be detected For instance ,Central/paracentral scotomas can be found in optic neuritis and open angle glaucoma.