| general | professional | clinics |



EYE ADVICE: Professional Papers


C. Eye Preference and Meridional Accommodation

When the visual system is under some strain to maintain optimal vision through both eyes, I have found that there is a tendency for preferential use of one eye. This eye is the one that is best suited to provide optimal vision for the required work.

(i) 1° PMA and Eye Preference

In cases of significant WTR corneal toricity, one may find that more 1° PMA is exerted in the preferred eye if there is an associated finding of significant spherical anisometropia or a difference in the corneal toricities. The preferred eye is usually the one which has less corneal toricity and less spherical ametropia. The difference in the subjective cylinder between the two eyes is usually greater than the difference in corneal toricity. Assuming equal amounts of intra-ocular astigmatism other that that due to MA (see section E below), this would imply that 1° PMA is more effective in the preferred eye in overcoming the corneal toricity. It also implies that Hering's law of equal innervation is not strictly obeyed.

Fick (1889) from his paper "On Unequal Accommodation", came to conclude that "one eye can act independently...within certain limits". (Quoted by Fletcher).






Paper 1 - Meridional (Astigmatic) Accommodation  Abstract

Physiology of Meridional Accommodation (A) Ciliary Muscle Action and Innervations
(B) Corneal Changes due to Ciliary Muscle Action
(C) Theory of Initiation of Meridional Accommodation

Clinical Implications of Meridional Accommodation


(A) Astigmatic Changes Related to WTR Corneal Toricity (i) Latent Astigmatism
(ii) Primary Accommodative Astigmatism (PAA)       (B) Reflex or 2°PMA and Induced ATR Astigmatic Changes
(C) Eye Preference and Meridional Accommodation (i) 1° PMA and Eye Preference
(ii) 2° PMA and Eye Preference (D) Proactive Prescribing for Presbyopia (i) Phakic Presbyopes
(ii) Pseudophakes and ATR Corneal Changes (E) Refractive Techniques and MA (i) Balancing Meridional Accommodation
(ii) Binocular Test of Cylinder Power (F) Further Clinical Subject Areas and Meridional Accommodation (i) Preventing Induced Oblique Astigmatism in Children
(ii) Low Vision
(iii) Keratoconus
(iv) Hard Contact Lenses
(v) PRK and PARK (Photorefractive Astigmatic Keratectomy)



Paper 2 - Common Chronic (Infective) Conjunctivitis and Nasal Rinsing

Paper 3 - Primary Open-Angle Glaucoma

general | professional | clinics


(C) 1997-2011, Kon Zagoritis