Sensory System Disorders: Ear and Eye

TL;DR

This unit covers common disorders of the ear and eye, focusing on their pathophysiology, differences, and management. You'll learn about ear conditions like otitis media, Meniere's disease, and deafness, along with eye conditions such as refractive errors, cataracts, and glaucoma. Understanding these topics is key for adult health nursing.

1. The Mental Model

Think of the ear and eye as complex sensory organs, each with specific structures vulnerable to various conditions. Many disorders stem from infection, inflammation, or structural changes, impacting a person's ability to hear or see.

2. The Core Material

Ear Disorders

Otitis Media

This is an inflammation or infection of the middle ear.
* Pathophysiology: Often caused by Eustachian tube dysfunction, leading to fluid accumulation behind the eardrum, which can then become infected by bacteria or viruses.
* Difference between CSOM and ASOM:
* ASOM (Acute Suppurative Otitis Media): Sudden onset, short duration, usually associated with an upper respiratory infection. Symptoms include ear pain, fever, and hearing loss.
* CSOM (Chronic Suppurative Otitis Media): Persistent, recurring infection with a perforated tympanic membrane and discharge, lasting longer than 3 months.
* Tubotympanic and Atticoantral Difference (Types of CSOM):
* Tubotympanic (Safe Type): Affects the pars tensa (lower part of the eardrum), usually with a central perforation. Less aggressive, often associated with mucous discharge, generally good prognosis.
* Atticoantral (Unsafe Type): Affects the pars flaccida (upper part of the eardrum) and bony structures, often with a marginal or attic perforation. More dangerous, can involve cholesteatoma (skin cyst), leading to bone erosion and complications like hearing loss, vertigo, or even brain abscesses.

Meniere's Disease

A disorder of the inner ear that causes episodes of vertigo, tinnitus, hearing loss, and a feeling of fullness in the ear. It's thought to be due to an excess of endolymphatic fluid.

Epistaxis

This is a nosebleed. While technically a nasal disorder, it's often grouped with ENT topics due to anatomical proximity. It can be anterior (most common, from Kiesselbach's plexus) or posterior (less common, more severe bleeding).

Foreign Bodies in External Ear

Objects lodged in the ear canal. Symptoms include pain, buzzing, discharge, and hear