Search results
Results from the WOW.Com Content Network
Nyctalopia (/ ˌ n ɪ k t ə ˈ l oʊ p i ə /; from Ancient Greek νύκτ-(núkt-) 'night' ἀλαός (alaós) 'blind, invisible' and ὄψ (óps) 'eye'), [1] also called night-blindness, is a condition making it difficult or impossible to see in relatively low light. It is a symptom of several eye diseases.
Some mental control can be exerted over these closed-eye visualizations, but it usually requires a bit of relaxation and concentration to achieve. [1] [2] When properly relaxed, it is possible to cause regions of intense black, bright white or even colors such as yellow, green, or pink to appear in the noise. These regions can span the entire ...
In a left esotropia, the left eye 'squints', and in a right esotropia the right eye 'squints'. In an alternating esotropia, the patient is able to alternate fixation between their right and left eye so that at one moment the right eye fixates and the left eye turns inward, and at the next the left eye fixates and the right turns inward. This ...
One example of a pressure phosphene is demonstrated by gently pressing the side of one's eye and observing a colored ring of light on the opposite side, as detailed by Isaac Newton. [ 7 ] [ 8 ] [ 9 ] Another common phosphene is "seeing stars" from a sneeze , laughter, a heavy and deep cough, blowing of the nose , a blow on the head or low blood ...
In a sixth nerve palsy one would expect that, over the 6 month observation period, most patients would show the following pattern of changes to their ocular muscle actions: firstly, an overaction of the medial rectus of the affected eye, then an overaction of the medial rectus of the contraletral eye and, finally, an underaction of the lateral ...
Intraocular pressure varies throughout the night and day. The diurnal variation for normal eyes is between 3 and 6 mmHg and the variation may increase in glaucomatous eyes. During the night, intraocular pressure may not decrease [ 17 ] despite the slower production of aqueous humour. [ 18 ]
Visual acuity with eye chart at Near 15.7 inches (400 mm) and without (sc: Latin sine correctore) correctors (spectacles); Ncc is with (cc: Latin cum correctore) correctors. See Visual_acuity#Legal_definitions: VA OS Left visual acuity VA OD Right visual acuity VDU Visual display unit VF Visual field VPS Variable prism stereoscope WD
This is the reverse of a redout, or a reddening of the vision, which is the result of negative g-forces caused by performing an outside loop, that is by pushing the nose of the aircraft down. Redouts are potentially dangerous and can cause retinal damage and hemorrhagic stroke .