Hearing Impairment

Adopted and edited from:

Conditions Which Have a Significant Association of Visual Problems or Visual Impairment.

Compiled by Tanni L. Anthony, Ed.S. – June 1993

Background Information

It is estimated that 60% of children who are hearing impaired have some form of a visual problem.  The most common problems are refractive conditions and/or strabismus.  There is also a low incidence of congenital cataracts and glaucoma.  Specific high risk populations include children with rubella, Usher syndrome, CMV, or post-meningitis.

Functional Vision Implications

Children who have congenital rubella often have visual loss associated with congenital cataracts.  The presence or formation of a cataract will result in a loss of visual acuity and visual field constriction.

Symptoms of uncontrolled infantile glaucoma include excessive tearing, photophobia, eye ball enlargement and blepharospasms (spasms of the eyelids).  Surgical intervention is the treatment of choice in many cases of infantile glaucoma.  Because the human eye is only stretchable until the age of three, the on set of glaucoma after this age does not result in buphthalmus, but follows the typical course of adult glaucoma.

In the early stages of adult glaucoma, functional signs of visual impairment may not be demonstrated.  In advanced glaucoma, several symptoms such as poor night vision, photophobia, lens opacity and visual field loss are typical.  Decrease in visual acuity is dependent on the amount of tissue damage in late stage glaucoma.  Decreased visual acuity may also cause difficulty with reading.

In rare instances, a child may experience an acute glaucoma attack.  Common symptoms are nausea, redness of the eye, hazy cornea, headache and extreme pain.  Permanent visual loss, tissue damage or blindness can result in a few days without early medical treatment.

Key characteristics of retinitis pigmentosa, the eye condition associated with Ushers Syndrome, are due to the degeneration of the rods which may result in loss of peripheral vision and night blindness.  The child with advanced retinitis pigmentosa may exhibit difficulty with mobility and in adapting to different lighting situations, (e.g., moving from outdoor to indoor lighting).  With retinitis pigmentosa, the child’s visual acuity is generally within normal ranges unless other complications occur affecting the macula area.  Some children may have inverse or atypical retinitis pigmentosa with macular or central retinal involvement, resulting in ring-like or “donut” shaped fields of view.  This macular involvement also affects reading ability and color discrimination.