H&N: Eye and Throat. Weird Flashcards
What structures are present in the apex of the orbital cavity?
- Superior orbital fissure
- Inferior orbital fissure
- Optic canal
What protect the eye ball from injury?
Tough orbital rim
What are the important anatomical reactions of the orbit?
- Paranasal air sinuses
- Nasal air cavity
- Anterior cranial fossae
What are the implications of the anatomical relation of the orbit?
- Orbital trauma
- Spread of infection
What are the weakest parts of the orbital cavity?
- Medial wall
- Floor of the orbit
What are symptoms of an orbital blow out fracture?
- History of trauma to the eye
- Painful periorbital swelling
- Double vision
- Impaired vision
- Anasthesia over affected cheek on affected side
How does an orbital blow-out fracture occur?
-Sudden increase in intra-orbital pressure fractures floor of the orbit
What are the effects of an orbital blow out fracture?
- Orbital contents and blood can prolapse into maxillary sinus
- Structures can be trapped at the fracture site such as extra orbital muscle near floor or orbit
What separates the eyelid fat and orbicularis oculi muscle?
Orbital septum
What is the function of the orbital septum?
Acts as a barrier against infection spreading from the pre-septal space to post-septal
What is peri-orbital cellulitis?
- Cellulitis of orbital structures.
- Can be pre-septal or post-septal
- Increasing degrees of severity
What are the precursors to periorbital cellulitis?
- Bites
- Periorbital trauma
- Sinuses (fronto-ethmoidal)
What are the complication of periorbital cellulitis?
- Abscess formation
- Spread of infection intracranially
- Cavernous sinus thrombosis
Which veins can infection of the orbit spread through?
- Opthalmic veins (most likely)
- Pterygoid venous plexus
- Facial vein
What is a meibomian cyst?
- Blockage of a meibomian gland.
- Prevention of evaporation of tear film and spillage is affected
What is a stye?
-Infection of the eyelash follicles
Is the cornea covered by the conjunctivae?
No. The conjunctivae extends to the limbus which is the edge of the cornea and reflected on the inner surface of upper and lower eyelid.
What is conjunctivitis?
When the conjunctiva become inflamed, blood vessels dilate and eye appears red.
What is a subconjuctival haemorrhage?
-Haemorrhage from blood vessels in conjunctiva that is readily visible
Where does the blind spot lie on the opthalmascope?
Medially on optic disc. Where the optic nerve is transmitted
What is glaucoma?
-Drainage of aqueous humour from anterior chamber can be blocked. Can lead to irreversible damage and death of the optic nerve
What is an open angle glaucoma?
- Deterioration of trabecular meshwork
- Aqueous humour cannot drain to the canal of Schlemm
- Present with visual field loss and cupping of the optic disc
-Chronic (age)
What is a closed angle glaucoma?
- Narrowing of iridocorneal angle
- Rapid rise in the intra-ocular pressure
- Presents with sudden onset of painful red eye, blurred vision, fixed or sluggish semi dilated oval shaped pupil, nausea, vomiting
- Acute
What is the effect of the glaucoma?
- Rise in intra-ocular pressure and damage to optic nerve
- Optic disc cupping occurs
- Sight threatening
What is the accommodation reflex?
- Light rays from near-objects are more divergent and require greater refraction to being them into focus on retina
- Autonomic constriction of the pupil
- Eyes converge
- Lens becomes more biconcave due to contraction of the ciliary muscle
Which extra-ocular muscles are not supplied by the oculomotor nerve?
- Lateral rectus by the abducens nerve
- Superior oblique by Trochlear
How do we isolate the action of superior oblique?
- Move the eyeball to a medial position
- Move the eyeball down
How do we isolate inferior rectus?
- Move the eyeball into the lateral position
- Move the eyeball down
How do we isolate the action of inferior oblique?
- Move the eyeball into the medial position
- Move the eyeball up
How do we isolate the action of superior rectus?
- Move the eyeball into the lateral portion
- Move the eyeball up
What is sialolithiasis?
- Salivary stones.
- Most are located in the submandibular glands
- Leads to dehydration and reduced salivary low
What are the symptoms of sialolithiasis?
- Pain in gland
- Swelling
- Infection
What is used to investigate salivary stones?
Sialogram
What are the symptoms of tonsillitis?
- Fever
- Sore throat
- Pain/difficulty swallowing
- Cervical lymph nodes
- Bad breath
How do peritonislar abscesses form?
- Can follow on from tonsillitis
- Can arise on its own
What are the symptoms of peritonsillar abscess?
- Severe throat pain
- Fever
- Bad breath
- Drooling
- Difficulty opening mouth
What is found in the oropharynx?
Palatine tonsils between Palatoglossus and Palatopharyngeal
What is found in the laryngopharynx?
Piriform fossa
What is Killian’s dehiscence?
Weakness found between the thyropharyngeal and cricopharyngeal muscle. These 2 are parts the inferior constrictor muscle
What is a pharyngeal pouch?
A posteriomedial (false) diverticulum. Could be due to
- Failure of the upper oesophageal sphincter to relax
- Abnormal timing of swallowing
- Essentially there is higher pressure in laryngo pharynx
- Weakness between muscle belly of the inferior constrictor muscle produces out pouching of pharyngeal mucosa
What are the symptoms of pharyngeal pouches?
- Dysphagia
- Bad breath
- Regurgitation of food
- Occasional choking on fluids
- General difficulty swallowing
What are the symptoms of pharyngeal pouches related to?
Food material collecting in pouch or disruption of swallow
What are some causes of dysphagia?
Stroke
Progressive neurological disease
COPD
Dementia
What are signs and symptoms of dysphagia?
- Coughing and choking
- Sialorrhoea
- Recurrent pneumonia
- Change in voice/speecj
- Nasal regurgitation
What are the 3 layers of the eye?
- Sclera (fibrous and tough)
- Chorioid (Vascular and muscular)
- Retina (rods and connes)
What connects the choroid and iris?
-Ciliary body which is vascular and muscular
What is uveitis?
- Inflammation of the choroid layer
- Presents with a red and painful eye which is worse when focusing or attempting to look at bright lights
- Autoimmune associated (AS, IBS)
What is the purpose of pigment layer and where does it lie?
- Between the choroid and retina
- Cells contain melanin
- Plays a role in helping absorb scattered light that has passed into the eye.
- Reduces reflection and allow us to focus images appropriately on the retina
How is vision affected in people with albinism?
- Lack of melanin in pigmented layer
- Wear glasses to prevent the scattering of light
What is the macula?
- Concentration of cone cells
- Cone cells have high visual acuity
- Centre of the macula is the fovea and has a rich density of only cones
What is retinal detachment?
- Pigmented epithelial cell layer can detach from neurosensory cell layer in certain layer
- Photoreceptors at the site of detachment are no longer able to function resulting in visual disturbance (lack of blood supply)
What is the purpose of the rods?
- Vision in low light
- Doesn’t discern colours.
- Abundant in the periphery
Where is the anterior chamber?
-Space between cornea and Iris
Filled with aqueous humour
Where is the posterior chamber?
-Space between the Iris and lens
Filled by aqueous humour and ciliary body and processes found in this chamber
What are cataracts?
Degradation of proteins in the lens which can cause it to become clouded and less transparent. Occur gradually
Which two muscles are found in the iris and what is their purpose?
- Sphincter pupillae and dilator pupillae
- Acts to control the size of the pupil and are controlled by the autonomic nervous system
What is presbyopia?
As we age
- Lens becomes dense, less elastic and more difficult to change shape
- Thus, the ability to accommodate and focus on near-objects becomes impaired as well get older
What is the hole on the medial side of the lower eyelid and its purpose?
- Puncta
- Collects tears
What are the steps to take clinical examination of the eye?
IVA FROM
I - Inspection of the eye
VA - Visual acuity tested using Snellen Chart
(V)F - Tested using Confrontation
R - Test te reflex. Direct and consensual reflex and accommodation reflex.
O - Use of an ophthalmoscope to visualise back of the eye.
M - Test the eye movements
What are the borders of the oral cavity?
Anterior: Oral fissure
Posterior: Oropharyngeal isthmus
Lateral and medial wall: Anterior and posterior pillars of faucet formed by the palatoglossus anteriorly and the palatopharyngeal posteriorly
What are the innervations of the extrinsic muscles of the tongue?
Hypoglossal nerve
- Genioglosus
- Styloglossus
- Hyoglossus
Vagus nerve
-Palatoglossus
Where are the parts of the pharynx located?
Nasopharynx - C1
Oropharynx - C2-C3
Laryngopharynx - C3-C6
What is located externally on the walls of the pharynx?
- Superior constrictors
- Middle constrictors
- Inferior constrictors
What innervates the constrictors of the pharynx and what is their action?
Vagus nerve
Relax and contrat to propel bolus into the oesophagus
Which parts of the pharynx and soft palate are supplied by the vagus nerve?
-All the muscles of the pharynx except stylopharyngeus
What is the sensory innervation of parts of the pharynx?
Nasopharynx - Maxillary Nerve
Oropharynx and Eustachian tube - Glossopharyngeal Nerve
Laryngopharynx - Vagus Nerve
What happens to the pharyngeal tonsils in adulthood?
They atrophy after puberty
What is a potential site for foreign bodies in the larygngopharynx?
- Piriform fossa is a potential site
- Also a site for cancer
What are the extrinsic longitudinal muscles muscles of the pharynx?
- Stylopharygeus (glossopharyngeal)
- Palatopharyngeus (vagus)
- Salpingopharyngeus (vagus)
What is the function of the extrinsic longitudinal muscles of the pharynx?
- Elevation of the larynx
- Widen and shorten the pharynx
