1500 unit 3

SENSORY PERCEPTION: Aging of the Ear and Presbycusis

Overview of Aging and Hearing Loss

Aging can lead to significant changes in the ear and sensory perception. Notably, it causes the cerumen (earwax) to harden and increase the likeliness of impaction due to a higher keratin content. Key terms and concepts include:

Presbycusis
  • Definition: Progressive hearing loss associated with aging.
  • Characteristics: It is characterized by degeneration of the organ of Corti and difficulty perceiving high-frequency sounds.
  • Aging Effects:
    • After the age of 60, noticeable damage to hair cells in the organ of Corti occurs, as these damaged cells cannot be replaced, leading to a preference for softer tones.
    • Commonly lost sounds include high frequencies like /f/, /s/, /k/, and /sh/.
Behavioral Indicators
  • Individuals may exhibit difficulty in hearing high-frequency sounds, prefer quieter environments, or physically turn their heads during conversations to better read lips and context for understanding.
  • Recommendations: Pull individuals into a quieter room to facilitate conversation.

Cerumen and Its Management

  • Nature of Cerumen: Naturally produced substance in the ear that traps pathogens and has antimicrobial properties. Can appear in various colors such as gold, brown, or light yellow.
  • Excess Cerumen: Can be removed gently by irrigation (using warm water) or professional cleaning. Available OTC earwax removal kits involve:
    • Preparing by lying down, applying prescribed drops, and using cotton balls to manage drainage.
    • Seeking professional assistance if OTC methods fail.

Types of Hearing Loss

1. Conductive Hearing Loss
  • Definition: Involves mechanical interference of sound conduction through the external auditory canal, eardrum, or middle ear, such as cerumen impaction.
2. Sensorineural Hearing Loss
  • Definition: Results from issues with hair cells, nerve endings, or blood supply in the inner ear, preventing the brain from interpreting sounds, even if they can be heard.
  • Causes: Can be congenital, or acquired due to hereditary factors, viral infections, disease, or trauma.
  • Example: Presbycusis where the organ of Corti degenerates.
3. Neural Hearing Loss
  • Definition: Originates in the auditory nerve or brainstem.

Hearing Loss Tests and Instruments

Rinne Test
  • Purpose: Compares air conduction (AC) to bone conduction (BC) using a tuning fork to identify conductive vs. sensorineural hearing loss.
  • Procedure:
    1. Strike the tuning fork and position it 2 inches from the mastoid process.
    2. Ask when they no longer hear the sound, then move the fork in front of the ear.
  • Results Interpretation:
    • Normal: AC is twice as long as BC (AC > BC).
    • Conductive Hearing Loss: BC is greater than AC.
    • Sensorineural: AC is heard longer than BC but less than double the time.
Weber Test
  • Purpose: Tests sound lateralization.
  • Procedure: uses a tuning fork placed at the center of the forehead.
  • Results Interpretation:
    • Sound heard in the affected ear indicates conductive loss (blockage).
    • Sound heard in the unaffected ear indicates sensorineural loss.

Pediatric Indicators of Hearing Loss

Signs in Infants
  • Lack of a startle reflex to loud noises or failure to turn towards sounds.
Signs in Toddlers and Preschoolers
  • Lack of speech, use of gestures for communication, or unintelligible speech.
Signs in School-aged Children
  • Declining academic performance and limited social interactions.

Types of Hearing Loss in Pediatrics

Conductive Hearing Loss
  • Caused by tympanic membranes that cannot vibrate properly due to cerumen buildup, otitis media, or foreign bodies.
Sensorineural Hearing Loss
  • Damage to the auditory nerve or cochlea; can be congenital (example: Rubella) or acquired due to toxic exposures.
Combined Hearing Loss
  • A mix of conductive and sensorineural, with normal tone perception being equal in both ears.
Hearing Tests
  • Whisper Voice Test: Assesses hearing by whispering two-syllable words at a distance while occluding one ear.
  • Romberg Test: Evaluates vestibular function/balance by determining if the subject can maintain posture when eyes are closed.

Cochlear Implants and Therapeutic Measures

Cochlear implants serve as therapeutic measures for hearing loss. Other measures include hearing aids, assistive devices like flashing lights or vibrating alerts (for smoke alarms), and trained hearing service dogs.

Childhood Ear Disorders and Otitis Media

Common Childhood Ear Issues
  • Impaction of cerumen and foreign bodies.
  • Otitis Media: A viral/bacterial infection that causes inflammation and fluid buildup behind the tympanic membrane.
    • Common Causes: Eustachian tube dysfunction allows for inflammatory fluid/pus buildup—most common illness in children aged 6-36 months.
    • Pathogens: Common organisms include Moraxella Catarrhalis, Haemophilus Influenzae, and Streptococcus Pneumoniae.
    • Types of Otitis Media:
      • With Effusion: Fluid/pus present.
      • Without Effusion: Inflammation present without fluid or pus.
Treatment for Otitis Media
  • Viral Infections: No specific treatment.
  • Bacterial Infections: Treated with oral antibiotics or tympanostomy tubes (Myringotomy) to relieve pressure.

Anatomy and Disorders of the Ear

External Ear Disorders

  • Common issues include cerumen impaction, foreign bodies, and external otitis (swimmer's ear).
  • Conditions also include sebaceous cysts, keloids, and exostoses/osteomas (bony growths).

Middle Ear Disorders

  • Otitis Media: Subjects to trauma and infections.
  • Serous Otitis: Fluid in the middle ear without infection.
  • Otosclerosis: A condition of abnormal bone growth causing stapes fixation, often necessitating surgery (stapedectomy).
Symptoms of Ear Disorders
  • Symptoms can include irritability, ear pulling, fever, earache, and systemic symptoms like diarrhea from infection response.
  • Physical signs include a red, bulging, non-mobile tympanic membrane due to infection.
Treatments for Middle Ear Disorders
  • Bacterial infections require antibiotics, while tympanostomy tubes help relieve pressure.

Issues of the Ear

Infections
  • External Otitis can result in pain, drainage, swelling, and itching.
  • Cerumen Impacted: The ear usually cleans itself; however, older adults are at increased risk for hardening keratin and associated hearing loss.
External Trauma and Complications
  • Hematomas, avulsions, and cartilage trauma can lead to swelling and damage, requiring careful management if untreated.

Inner Ear Disorders

  • Ménière’s Disease: A balance disorder characterized by a triad of symptoms: vertigo, hearing loss, and tinnitus due to fluid disturbance in the inner ear.
  • Labyrinthitis: An inflammation/infection that can cause acute problems, resulting in vertigo, sensorineural hearing loss, and pain.
  • Acoustic Neuroma: A benign tumor of the 8th cranial nerve leading to unilateral sensorineural hearing loss and associated symptoms.
Diagnosing Inner Ear Disorders
  • Diagnostic procedures involve CBC lab tests, audiometric tests, and physical examinations to evaluate symptoms.
Treatment for Inner Ear Disorders
  • Management may include surgical removal of tumors, antibiotics for infections, and supportive care.

Otosclerosis

  • Involves hardening due to new bone formation, leading to conductive hearing loss.
  • Treatment options include hearing aids, ossiculoplasty, and stapedectomy to improve sound transmission to the inner ear.
Post-Operative Care for Ear Surgeries
  • Patients should maintain specific positions, avoid strenuous activities, and can experience nausea or dizziness that may require analgesics or anti-nausea.

Age-Related Vision Changes

Aging typically leads to numerous vision changes characterized by issues such as presbyopia, deterioration of peripheral vision, reduced tear production, sensitivity to glare, problems with depth perception, and a yellowish ring around the iris.

  • Vitamin A deficiency: Associated with corneal damage and night blindness. Foods high in Vitamin A include a range of vegetables and fruits.

Data Collection for Eye Examination

  • Begins with taking a subjective health history, followed by objective tests.
  • Family history is essential, focusing on conditions like diabetes, hypertension, and cataracts. Comprehensive eye exams are thus recommended.
  • Diagnostic Tests include Snellen Chart testing, confrontation testing