Convergence Insufficiency

Updated: Jul 25, 2018
  • Author: Eric R Eggenberger, DO, MS, FAAN; Chief Editor: Hampton Roy, Sr, MD  more...
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Convergence insufficiency is a common condition that is characterized by the inability to maintain proper binocular eye alignment on near objects. [1, 2] Patients with symptomatic convergence insufficiency report difficulty with near work, including blur at near, eye strain, or frank diplopia. Abnormalities on examination include exophoria or exotropia at near, reduced fusional vergence amplitudes, and an increased near point of convergence. [3] Convergence insufficiency is a common disorder in young and aging adults and may be isolated and idiopathic or associated with other neurologic disease.

Convergence is the disconjugate adduction of the eyes for vision of near targets. Appropriate convergence is necessary for clear binocular vision at near, and binocular foveation is essential for stereopsis. Convergence is a component of the near-response triad, along with accommodation of the lens and miosis. The primary stimulus for the near response is positional disparity of an image on the retina, with a smaller contribution from blurring of objects at near. These can be objectively measured by measuring the convergence response to accommodative stimuli (accommodative convergence to accommodation ratio [AC/A]) and the accommodative response to convergence stimuli (convergence accommodation to convergence ratio [CA/C]). Small imprecisions in this system can be compensated for by a cortical process called sensory fusion. [4] However, when convergence responses to near are sufficiently reduced, convergence insufficiency results.



Convergence insufficiency is a supranuclear disorder of ocular motility. In the cerebral cortex, the primary and secondary visual cortices respond to binocular disparity and depth. The secondary visual cortex can generate reflexive vergence eye movements. The right parietal lobe directs visual attention, and the frontal eye fields generate the signal for voluntary shifts from far to near targets, as well as tracking of approaching objects. Additional structures in the midbrain and pons are involved in these pathways and coordinating convergence eye movements with versions. Regions of the cerebellum contribute to near response and to smooth vergence tracking. The supraoculomotor area in the midbrain, adjacent to the oculomotor nuclei, is the final common pathway for convergence eye movements prior to the oculomotor nucleus. [4] Considering this distributed network, convergence insufficiency is typically poorly localizing and, as an isolated finding, is much more likely to result from an inherent imbalance within this system or decompensation secondary to multifocal cerebral dysfunction. This imbalance may be provoked by a reduction in the accommodative stimulus for vergence, as in presbyopic patients with new correction for near acuity.

Considering the interactions between the vergence and accommodative responses to similar stimuli, it is not surprising that both vergence and accommodation may be affected. [5]




United States

In children, the prevalence of convergence insufficiency is estimated at 4.2%-6%. In adults, the annual incidence is 8.4 per 100,000 population. By the ninth decade of life, approximately 70% of individuals may be affected. [6] The incidence increases with additional near work demand.

Convergence insufficiency is reported to be rare in children younger than 10 years. However, the increased visual demands of schoolwork and prolonged periods of reading exacerbate symptoms in older children. [7]


The prevalence of convergence insufficiency is the same in all industrial societies.


The morbidity of convergence insufficiency relates to the near point visual demands of the patient's activities. Eye strain, fatigue, frequent loss of place while reading, and frank binocular diplopia associated with near point tasks are among the reported symptoms of convergence insufficiency.


Convergence insufficiency has no racial predilection.


Convergence insufficiency has no sexual predilection.


The frequency of convergence insufficiency symptoms may increase with age as patients' ability to compensate for their relative divergent binocular alignment decreases with time.



The prognosis of convergence insufficiency is excellent in most patients, as conservative therapies can be quite effective. However, approximately one quarter of patients have significant increases in the near exodeviation 20 years from diagnosis. A small percentage of patients may require surgery or resort to monocular occlusion at near. [6]


Patient Education

Patients should be made aware that convergence insufficiency is a fairly common condition and that treatment is generally effective.