Eye Diagnostic Tests Overview

EYES - Diagnostic Tests

• Visual Acuity: Snellen chart used; person stands 20 ft away, reads lines until able to identify letters. 20/20 vision means someone can see at 20 ft what most people see at 20 ft.

• Refractive Exam: Determines refractive error. Anticholinergics are used to dilate pupils, providing better view of internal structures. Phoropter measures the need for glasses; different lenses are shown, and the person identifies the clearest view.

• Ophthalmoscopic Exam: Examiner looks through pupils to view the retina/internal structures using an ophthalmoscope.

• Slit Lamp: Microscope directing light onto the cornea to view the conjunctiva, cornea, anterior chamber, iris, lens, and anterior vitreous.

• Tonometer: Measures intraocular pressure (IOP). A small cone touches the numbed cornea to measure the force to flatten it.

• Refractive Errors (Table 80-1):

• Myopia: Light focuses in front of the retina; distant vision blurred.

• Hyperopia: Light focuses behind the retina; close vision blurred.

• Astigmatism: Light focuses at two different points on the retina; distorted vision.

• Presbyopia: Light focuses behind the retina; decreased close vision.

• Correction of Refractive Errors: Glasses or contacts.

• Types of Glasses: Bifocals (two lenses), Trifocals (three lenses).

• Contact Lenses: Fit directly on the cornea, float on tears.

EYES - Inflammatory/Infectious

• Conjunctivitis ("Pink Eye"): Inflammation of the conjunctiva; caused by bacteria, viruses, or allergies. Symptoms: pain, redness, swelling, itching, sometimes discharge. Treatments: antibiotic/antiviral eyedrops/ointments. Key teaching point: prevent eye rubbing, and do not touch dropper to eye.

• Hordeolum ("Stye"): Acute inflammation of eyelid oil/sweat gland. Caused by clogged gland. Symptoms: red, raised, swollen, painful, with pus. Treatment: warm compresses, topical antibiotic ointment. Severe cases need incision and drainage.

EYES - Structural Disorders

• Ectropion vs. Entropion: Ectropion - eyelid turns out; Entropion - eyelid turns in. Common in older adults due to aging.

• Ptosis: Drooping eyelid.

• Glaucoma: Increased fluid pressure within the eye.

• Open-Angle Glaucoma: Most common type; inadequate drainage of aqueous humor through trabecular meshwork. Symptoms may be unnoticeable until late stages (IOP fluctuation, visual field deficits, central field vision loss). Treatment: hypotensive agents (beta-blockers, miotics, carbonic anhydrase inhibitors).

• Angle-Closure Glaucoma: Aqueous humor blocked by iris bulge. Risk factors: diabetes, cardiovascular disease, hypertension, steroid use. Treatment: eye drops or oral medication (e.g., acetazolamide).

• Medications for Glaucoma:

• Acetazolamide (Diamox): Decreases aqueous humor production.

• Timolol maleate (Timoptic): Beta-blocker to lower IOP.

• Travoprost (Travatan Z): Increases aqueous outflow.

• Pilocarpine: Suppresses aqueous humor inflow.

• Cataracts: Opacity/cloudiness of the lens. Early symptom: seeing halos around lights. Other symptoms: diplopia, halos. Causes: age-related chemical changes in lens proteins. traumatic (foreign objects). Treatment: surgery (extracapsular cataract extraction/ultrasonic fragmentation).

• Macular Degeneration: Degeneration of the central retina.

• Age-related Macular Degeneration (AMD): Most common form, typically in those older than 60.

• Causes: Formation of drusen (yellow cellular deposits/debris). Other risk factors: smoking, aging, family history, hypertension, cholesterol, obesity, female gender. Symptoms: blurred vision, trouble seeing faces/colors, distorted vision, decreased visual acuity, presence of drusen.

• Dry vs. Wet AMD: Dry progresses slowly, no cure. Wet involves fragile blood vessels behind the macula that leak.

EYES - Trauma

• Contusion/Hematoma: Blunt eye injury causing swelling and bleeding around the orbit. Caused by blunt force trauma. Treatment: cold packs, then warm packs after 48 hours.

• Foreign Bodies:

• External: On corneal/conjunctival surface. Treatment: topical anesthetic.

• Internal: Penetrate cornea/sclera, inside the eye. Treatment: surgery.

• Hyphema: Hemorrhage into the anterior chamber of the eye. Cause: blunt trauma. Dangerous because it can lead to glaucoma/vision loss.

• Mydriatic vs. Miotic Meds: Mydriatic dilates; miotic constricts.

• Corneal Abrasions: Outer layer of cornea damaged. Caused by branches, fingernails, paper, contact lens injuries. Diagnostics: not explicitly stated. Treatment: antibiotic eye drops/ointment, pressure patching.

• Detached Retina: Separation of the retina from choroid. Causes: trauma, myopia, degeneration, surgery, tumors, retinopathy, extreme hypertension. Vision loss occurs after blood supply is cut off from the layers above it. Symptoms: blurry, no vision. No pain (reason not explicitly stated.)

EYES - Eye Surgery

• Pre-op Education: Steps of surgery, client's role, whether procedure is awake/asleep. Post-operative care review.
• Post-op Education: Avoid sudden movements, pressing on the eye, bending.
• Nursing Interventions: Client and family teaching emphasizing documentation and clarity for all clients especially older/confused clients.
• Major Post-op Complication: Report of any facial paralysis/ptosis immediately.

EARS - Diagnostic Tests

• Otoscopic Examination: Uses a lens and light to examine the external ear canal, tympanic membrane, and ear features.

• Audiometry (Pure Tone): Hearing test involving headphones connected to a machine used to diagnose conductive and sensorioneural loss.

EARS - Ear Irrigation

• Purpose: Rinse drainage, meds, remove wax/foreign bodies.
• Steps: Warm solution to body temperature, drape client, straighten ear canal, expel syringe air, insert syringe into meatus, irrigate, lie client on side, dry canal and ear.

EARS - Hearing Loss

• Conductive Hearing Loss: Disrupts sound waves to hearing organs. Most common cause: problems in auditory canal, eardrum, or ossicles.
• Sensorineural Hearing Loss: Disturbance of inner ear organs/transmitting nerve.
• Sensory - cochlear.
• Neural - 8th cranial nerve.

EARS - Hearing Loss Prevention

• Avoid excessive noise, keep volume down, wear protection. Protect ears, use ear plugs for swimming and in dusty environments. Do not place foreign objects in ears, dry ears after water exposure or swimming. Do not pick/pull ears or excessively clean them. Treat infections promptly. Get ear piercing from a professional.

EARS - External Ear

• Impacted Earwax: Often caused by pushing wax further in with foreign objects. Can lead to injury or infection. Treatment: irrigation. Education: do not attempt removal with objects like Q-tips.

• Foreign Bodies: Most common in children. Food becomes problematic due to moisture causing swelling and pain. Insects can sometimes be removed with a light or a small amount of ethanol.

• External Otitis (Otitis Externa): Inflammation of the external ear often due to chronic external ear inflammation. Treatment: antibiotics. Prevention: use earplugs in water activities.

• Punctured Tympanic Membrane: Could be caused by gunshot sounds or drastic pressure changes. Concern for the middle ear (eardrum).

EARS - Middle Ear

• Otitis Media: Middle ear inflammation. Cause: Fluid buildup in the middle ear. Children susceptible due to shorter/smaller auditory tubes. Common symptoms: crackling, fullness, hearing loss. Tools: otoscope. Treatments: antibiotic use or myringotomy. Recurring OM: tympanoplasty. Medications: (pain/fever) antipyretics; (infection) antibacterials.

EARS - Inner Ear

• Ototoxicity: Hearing and balance problems from medications. Medications include aminoglycoside antibiotics, macrolide antibiotics, loop diuretics, antimalarials.

• Ménière Disease: Inner ear's semicircular canals disrupted. Function: balance. Causes: (not clear, theories about herpes simplex). Symptoms: vertigo, nausea/vomiting, tinnitus. Treatment: antivirals, anti-vertigo medications. Medication classes: antiviral (e.g., acyclovir); anti-vertigo (e.g., meniett). Client Education: avoid sudden movements/loud noises, bright lights.

This quiz explores various diagnostic tests used in ophthalmology, including visual acuity tests, refractive exams, and methods for assessing intraocular pressure. Participants will learn about the purpose and procedure of each test, as well as common refractive errors. Perfect for students in the field of eye care or anyone interested in understanding eye examinations.