Indian Journal of Ophthalmology

: 1991  |  Volume : 39  |  Issue : 4  |  Page : 170--173

Effect of aniseikonia on fusion

Pradeep Sharma, Prem Prakash 
 Dr. Rajendra Prasad Centre for Ophthalmic Sciences, AIIMS, New Delhi 110 029, India

Correspondence Address:
Prem Prakash
Dr. R.P Centre for Ophthalmic Sciences. AIIMS New Delhi - 110029

Physiological aniseikonia is the basis of stereopsis but beyond certain limits it becomes an obstacle to fusion. It is not well established as to how much aniseikonia can be tolerated by the fusional mechanism. Different tests under different testing conditions have given a wide range of variation. On the synoptophore we had observed tolerance upto 35% aniseikonia in some cases. Under more physiological conditions on a polaroid dissociation stereoprojector we observed lesser baseline fusional vergences but tolerance in about 70% of the cases upto 30% aniseikonia while 25% could tolerate even 35% aniseikonia. However we realise that these indicate the maximal potential and not the symptom free tolerable limits.

How to cite this article:
Sharma P, Prakash P. Effect of aniseikonia on fusion.Indian J Ophthalmol 1991;39:170-173

How to cite this URL:
Sharma P, Prakash P. Effect of aniseikonia on fusion. Indian J Ophthalmol [serial online] 1991 [cited 2023 Jun 7 ];39:170-173
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