Special Senses Medical Conditions

Visual Acuity

Sharpness of vision

Snellen Eye Chart

Used to test visual acuity; where patient reads letters of various sizes from a distance of 20 ft

Colored Vision Test

Multicolored charts assess ability to recognize different colors

Tonometry

Measures interocular pressure

Tuning Fork Tests

Used to test for hearing loss and can help distinguish between perceptive and conductive hearing loss

Rinne Test and Result

Where a tuning fork is struck and then held on the mastoid process until the patient is unable to hear sound, then held outside the ear; a patient with healthy hearing will be able to hear sound again as air conduction of sound is faster than bone conduction of sound

Types of Hearing Loss

Conductive and Sensorineural

Conductive Hearing Loss

Occurs when sound cannot travel to the inner ear caused by external or middle ear dysfunction

Causes of Conductive Hearing Loss

Obstruction by cerumen or a mass, fluid in the middle ear, otosclerosis, or separation of ossicles in the middle ear

Sensorineural Hearing Loss

Deterioration of the cochlea

Causes of Sensorineural Hearing Loss

Aging, persistent exposure to loud noise, head trauma, or other systemic diseases

Presbycusis

Hearing loss as a result of aging

Hearing Amplification Tools Use and Examples

Used to treat patients with hearing loss that cannot be treated medically; ex. Hearing aids, cochlear implants

Cochlear Implants

Small electronic devices surgically implanted to stimulate the cochlea with sounds detected on a receiver

Acute Otitis Media

Bacterial infection of the middle ear

Eustachian Tube

Connects the middle middle ear to the throat

Acute Otitis Media Cause

When the eustachian tube is obstructed, causing fluid and mucus build up in the middle ear that is then infected with bacteria

Acute Otitis Media Symptoms

Otalgia, increased pressure in the ear, decreased hearing, and fever, decreased movement and erythematous tympanic membrane

Acute Otitis Media Complications

If left untreated, the tympanic membrane can rupture and chronic otitis media may develop

Acute Otitis Media Treatment

Tympanocentesis may be necessary for persistent infections to perform a C&S test and to relieve pressure behind the TM; may require surgical drainage via myringotomy

Vertigo

Sensation of movement when there is no motion or an exaggerated sense of movement in response to motion

Vertigo Cause

Disturbance in the inner ear from injury, infection, inflammation, or positioning, or labyrinthitis

Ménière’s Syndrome

Condition where patients experience episodic vertigo, hearing loss, tinnitus, and pressure in one ear

Labyrinthitis

Inflammation of the inner ear

Benign Paroxysmal Positioning Vertigo

Condition of vertigo that is associated with changes in the position of the head

Cataracts

Opacities of the lens of the eye and leading cause of blindness as patients age; can be genetic or result of systemic disease

Cataracts Symptoms

Painless but cause progressive blurry vision

Cataracts Treatment

Surgical removal of the lens and placement of an intraocular lens implant or phacolysis or phacoemulsification

Pacolysis, Phacoemulsification

Where the cataract is dissolved with ultrasound and then removed, and a lens implant is put in place

Conjunctivitis

Inflammation of the conjunctiva, pinkeye

Conjunctivitis Cause

Bacterial or viral infection, allergens, chemical irritants, and/or trauma

Conjunctivitis Symptoms

Redness of the eye, increased tearing, thick discharge from the eye that crusts while sleeping, itchy and burning eyes, blurry vision, or increased sensitivity to light

Conjunctivitis Discharge

watery when viral, purulent (pus) drainage when bacterial

Conjunctivitis Prognosis

Viral is self-limiting and will resolve within 14 days; Bacterial requires antibiotic eyedrops and resolves with 10-14 days

Glaucoma

Condition of increased intraocular pressure secondary to a backup of fluid in the eye

Glaucoma Complications

Increased pressure can damage the optic nerve and the cells of the retina, resulting in decreased vision or blindness

Aqueous Humor

Fluid that fills the anterior chamber of the eye, produced in the posterior chamber and passes through the pupil into the anterior chamber

Trabecular Meshwork

Exit of the anterior chamber of they eye

Canal of Schlemn

Leads to vascular system

Cause of Intraocular Pressure

When the flow of aqueous humor is slowed or blocked

Types of Glaucoma

Acute angle-closure glaucoma and chronic glaucoma

Acute Angle-Closure Glaucoma

Occurs when the acute angle of the anterior chamber is blocked completely, and the aqueous humor cannot flow out of the eye

Acute Angle-Closure Glaucoma Symptoms and Severity

Severe eye pain and blurry vision; medical emergency

Chronic Glaucoma

Occurs when the flow of aqueous humor in the eye is slowed through the trabecular meshwork

Chronic Glaucoma Symptoms

Discovered during routine eye examination as elevated intraocular pressure

Acute Angle-Closure Glaucoma Treatment

Reduce intraocular pressure with IV and topical medications, may be followed by surgical or laser iridectomy to prevent another closure

Chronic Glaucoma Treatment

Reduce intraocular pressure with topical medication and a trabeculoplasty