Introduction to the shadowscope

Normal value
If the pupil reflex moves in the same direction as the ophthalmoscope rotates, it is called along movement, which is the positive image seen by the fundus image; If the two move in opposite directions for the reverse, that is, the fundus image to see for the inverse image; If the pupil reflex does not show obvious movement, it is called immobility.
Clinical significance
Abnormal results: (1) Scissor saw two light bands in the pupil area, one moving forward and the other moving backward like scissors opening and closing, due to lens tilt, corneal scar or irregular astigmatism in the examined eye. (2) Spherical difference and negative spherical difference (caused by keratoconus). People who need to be checked: patients with myopia or farsightedness and astigmatism.
Matters needing attention
Unsuitable population: Patients with inflammation of other eye diseases. Contraindication before examination: in particular, attention should be paid to the presence of corneal turbidity, vitreous turbidity, nystagmus, strabismus and amblyopia. Inspection requirements: the viewing distance and the inspected person are only the direction.