This is due to the fact that the anatomy of the right main bronchus is wider and steeper than that of the left main bronchus, allowing objects to enter more easily than the left side. Unlike adults, there is only a slight propensity towards objects lodging in the right bronchus in children. This is likely due to the bilateral bronchial angles being symmetric until about 15 years of age when the aortic knob fully develops and displaces the left main bronchus.Signs and symptoms of foreign body aspiration in adults may also mimic other lung disorders such as asthma, COPD, and lung cancer. {

Causes
Most cases of foreign body aspiration are in children ages 6 months to 3 years due to the tendency for children to place small objects in the mouth and nose. Children of this age usually lack molars and cannot grind up food into small pieces for proper swallowing. Small, round objects including nuts, hard candy, popcorn kernels, beans, and berries are common causes of foreign body aspiration. Latex balloons are also a serious choking hazard in children that can result in death. A latex balloon will conform to the shape of the trachea, blocking the airway and making it difficult to expel with the Heimlich maneuver. In addition, if the foreign body is able to absorb water, such as a bean, seed, or corn, among other things, it may swell over time leading to a more severe obstruction.
So, the patient uses excessive accommodation to stimulate accommodative convergence to overcome reduced PFV. Risk factors
A large amount of near work is the main precipitating factor of accommodative excess. Pseudomyopia
Pseudomyopia also known as artificial myopia  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. Diagnosis
Differential diagnosis
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. Treatment
Optical: Cycloplegic refraction, and correction of Refractive errors if any 
Vision therapy
General: Relax from near work

See also
Spasm of accommodation
Convergence excess


== References ==