Anisometropia

Highly different visual defects as well as on the right and the left eye, e.g. right -2,00 dpt and left -6,00 dpt.

The differentiation between the refractive- and the axial anisometropia:

At the refractive anisometropia the visual defect is different because of the refractive balance of the cornea and the eye lens. At the axial anisometropia the different length of the eyes are the cause.

The differentiation between all around-anisometropia and the meridian anisometropia:

At the all around-anisometropia the difference value between the both eyes is almost identical in all meridians. If there is an astigmatism (corneal irregularity) with different axis positions, so the difference value between the both eyes is additional in all meridians uneven big = meridian anisometropia.

At the correction of an anisometropia with glasses, many more or less heavy shape factors or diminution of the glasses arise because of the variable values.
This leads to variedly big pictures on the retina. From about 3% difference in size (aniseikonia) a double image could appear or an eye could be repressed (suppression).
Furthermore, the variedly sturdy shape factors resp. Diminution of the glasses leads to a varying look of both eyes for the contemplator.
Moreover, at a correction of an anisometropia with glasses variedly big visual fields arise, varied eye movements has to be done in order to view binocular easy, without moving the head. At the view onto nearby objects, different amplitudes of accommodations have to be brought up and in addition different convergence angles of the right and the left eye are required in order to view easily in near distance. These phenomena disappear in a great measure when you change from glasses to contacts. In the case of a refractive anisometropia the contacts have advantage over the glasses. In the case of an axial anisometropia glasses are preferential. Often the contacts have also advantage over the glasses if an axial anisometropia has been diagnosed. On a partial aphakia (absence of the eye lens) there is a refractive ametropia. In that case contacts are very advisable.