Can a doctor detect strabismus in less than a minute? The answer is a resounding yes. Here are the methods that doctors use to quickly diagnose strabismus. Diagnosis of strabismus 1. Corneal light reflection method Let the examined person look at the light 33cm in front of him/her, if the corneal reflection point is located in the center of the pupil of both eyes, then the eye is orthotropic, i.e. no strabismus. If the corneal light reflection appears in the center of the pupil of one eye, but the other eye is at the pupil margin, the skew is about 10-15 degrees; at the corneal margin, the skew is about 45 degrees. 2, alternate masking method Let the examined person gaze at the light of 33cm, and then use the palm of the hand to repeatedly alternate between the left and right eyes to block the line of sight. Observe whether there is any rotation of the uncovered eye at the moment of alternate covering. This method is very sensitive and can detect occult strabismus or strabismus of 2 degrees or more. 3. Extraocular muscle function check method Let the examined person look at the light of 33cm, and the light move to the left, right, upper left, upper right, lower left, lower right directions respectively, and determine whether there is a problem with a certain muscle of one eye by observing whether the movement of both eyes is uncoordinated. Therefore, for a well-trained and skilled ophthalmologist, the basic skill of detecting strabismus within one minute has long been practiced in years of work. The above three examinations can detect the following conditions 1. the presence of strabismus 2. whether it is occult or dominant strabismus 4. the approximate degree of strabismus 4. whether the movement of both eyes is uncoordinated 5. which of the 12 extraocular muscles in both eyes are paralyzed or restricted as a direct result of the uncoordinated eye movement 6. which muscle movement abnormalities are primary and which movement abnormalities are secondary