Accommodative excess | |
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Accommodation | |
Specialty | Ophthalmology |
Symptoms | asthenopia, blurring of vision |
In ophthalmology, accommodative excess (also known as excessive accommodation or accommodation excess) occurs when an individual uses more than normal accommodation (focusing on close objects) for performing certain near work. Accommodative excess has traditionally been defined as accommodation that is persistently higher than expected for the patient's age. Modern definitions simply regard it as an inability to relax accommodation readily.[1] Excessive accommodation is seen in association with excessive convergence also.[2]
Accommodative excess may be seen in the following conditions:[3]
Use of systemic drugs like Morphine, Digitalis, Sulfonamides, Carbonic anhydrase inhibitors may cause accommodative excess.[4]
Accommodative excess may occur secondary to convergence insufficiency also. In convergence insufficiency near point of convergence will recede, and positive fusional vergence (PFV) will reduce. So, the patient uses excessive accommodation to stimulate accommodative convergence to overcome reduced PFV.[5]
A large amount of near work is the main precipitating factor of accommodative excess.[3]
Pseudomyopia also known as artificial myopia [6] refers to an intermittent and temporary shift in refractive error of the eye towards myopia. It may occur due to excessive accommodation or spasm of accommodation.[7]
Parinaud's syndrome, which can mimic some aspects of spasm of the near reflex, such as excessive accommodation and convergence; however, pupillary near-light dissociation, not miosis, is a feature of Parinaud's syndrome.[8]