Ear and Eye (ENT 2) Flashcards
What are the four categories of dizziness?
Vertigo
Presyncope
Disequilibrium
Light headedness
What is vertgio? How may this be described?
Imbalance of tonic vestibular signal
False sense of motion / spinning sensation
What is disequilibirum?
Symmetric vestibular loss, proprioceptive loss, cerebellar damage
Off balance / wobbly
what is presyncope?
Diffusely diminished blood flow / blood
Feeling of losing consciousness / blacking out
What is psychogenic?
Abnormality in the integration of afferent signal by CNS
Vague sumptoms
Possibly feeling disconnected with the environment
What may cause disequilibrium?
Cerebellar damage
Basal ganglia lesion
Cerebellar damage
What may cause presyncope?
Orthostatic hypotension
Hypoglycaemia
Cardiac arrhythmia
List some peripheral causes of vertigo
Benign paroxsymal positional vertigo (BPPV) Vestibular neuritis Meniere disease Otoscleroris Lavrynthitis
List some central causes of vertigo
Vestibular migraine CV disease Cerebellopontine angle and posterior fossa meningiomas MS Acoustic neuroma
How does BPPV present?
Attacks of sudden rotational vertigo lasting >30s are provoked by head turning
Other otological symptoms rare
How is BPPV diagnosed?
Establish important negatives:
No persistent vertigo
No speech, visual, motor or sensory problems
No tinnitus, headache, ataxia, facial numbness, dysphagia
Hallpike test +ve
What is an acoustic neuroma?
Usually painless benign subarachnoid tumours that cause problems by local pressure, and then behave as SOL
Rare = 1 / 100,000 / year
Where do acoustic neuromas usually arise?
Superior vestibular Schwann cell layer
Sometimes called vestibular schwannoma
How do acoustic neuromas present?
Progressive ipsilatural tinnitus +/- sensorineural deafness (cochlear nerve vompression)
Disequilibrium common
Vertigo rare
Trigeminal compression above tumour may give numb face
What investigations are done for an acoustic neuroma?
MRI for all those with unilateral tinnitus / deafness
Key differential = meningioma
What is the management of an acoustic neuroma?
Surgery is difficult and not often needed eg if elderly
Methods of preserving hearing and facial nerve eg stereotactic radiosurgery
What is tinnitus?
Perception of sound in the ears or head where no external source of the sound exists
How can tinnitis be divided?
Objective (audible to examiner) - rare
Subjective (audible only to pt)
What can cause objective tinnitis?
1) Vascular disorders = Pulsatile vibratory sounds
AV malformations, glomus tumours
2) High output cardiac states = Pulsatile sounds
Pagets, hyperthyroid, anaemia
3) Myoclonus of palatal of stapedius / tensor tympani muscles = audible click
4) Patulous eustachian tube = prolonged opening, causing abnormal sound transmission to ear
What can cause subjective tinnitis?
Most commonly associated with disorders causing sensorineural hearing loss eg presbycusis, noise induced hearing loss, Menieres (unilateral)
Conductive deafness less common eg impacted wax, otosclerosis
Otitis media with effusion Thyroid dysfunction DM MS Acoustic neuroma Anxiety
List some ototoxic drugs?
Cause bilateral tinnitis with associated hearing loss
Cisplatin and aminoglycosides = permanent hearing loss
Aspirin, NSAIDs, quinine, macrolides and loop diuretics are associated with tinnitus and reversible hearing loss
List some aminoglycosides
Gentamicin Tobramycin Plazomicin Streptomycin Neomycin
What is the pathophysiology of tinnitis
Poorly understood
Spontaneous otoacoustic emissions
Altered or increased spontaneous activity of auditory nerve
Inappropriate feedback pathways in auditory-limbic system
What tests can be done for tinnitis?
Audiometry
Tympanogram
MRI for unilateral tinnitus to exclude acoustic neuroma
What is the treatment of tinnitus?
Treat any underlying cause
Explain - it common and usually improves with time via habituation
Hearing aids - if hearing loss >35db, improves perception of background noise and makes tinnitus less apparent
Psychological support eg sound therapy (radio / fan use to mask sound)
CBT
What is glaucoma?
Group of eye diseases associated with acute or chronic destruction of the optic nerve with or without increased intraocular pressure (IOP)
Aqueous humor is produced by the ciliary body on the iris, flows from the posterior chamber through the pupil into the anterior chamber, and then drains back into the venous system via the trabecular meshwork in the angle of the anterior chamber.
- Any process that can disrupt the flow can lead to optic nerve damage
What are the two main types of glaucoma?
Open angle (90%) = slowly progressive, initially often asymptomatic, but leads to peripheral vision loss over time (peripheral to central)
Acute angle closure glaucoma
What is acute angle closure glaucoma?
Angle of anterior chamber narrows narrows acutely causing a sudden rise in IOP to >30mmHg (normal range is 15-20)
Pupil becomes fixed and dilated and axonal death occurs
What is primary vs secondary acute angle closure glaucoma?
Primary = anatomical predisposition Secondary = pathological processes eg traumatic haemorrhage pushing the posterior chamber forwards
What factors predispose acute angle closure glaucoma?
Hypermetropia (long-sightedness)
Pupillary dilatation
Lens growth associated with age (typically 40-60yr)
Asian
How does acute angle closure glaucoma present?
severe pain: may be ocular or headache
decreased visual acuity
symptoms worse with mydriasis (e.g. watching TV in a dark room)
hard, red-eye
haloes around lights
semi-dilated non-reacting pupil
corneal oedema results in dull or hazy cornea
systemic upset may be seen, such as nausea and vomiting and even abdominal pain
What is the management of acute angle closure glaucoma?
Urgent referral to opthalmologist for gonioscopy - angle between iris and cornea checked (drainage angle)
Triad of:
1) Beta blockers to suppress aqueous humour production eg timolol 0.5%
2) Pilocarpine 2-4% drops/2hrs - pupillary constriction opens trabecular mesh work and increases drainage
3) 500mg IV acetazolamide stat then 250mg/8hr PO/IV - reducing aqueous humour formation
Admit to monitor IOP
What is done once IOP is controlled in acute angle closure glaucoma?
Peripheral iridectomy - a piece of iris is removed (at ‘12 o clock’) in both eyes to allow aqueous to flow
What are some complications of acute angle closure glaucoma?
Visual loss
Central retinal artery or vein occlusions
Repeated episodes
What is the management of open angle glaucoma?
Prostaglandin eye drops eg latanoprost 50mcg/ML / travoplost
Laser trabeculopasty
Surgical trabeculectomy
What is a cataract?
Any opacity in the lens
Leading cause of blindness
How common are cataracts?
75% of >65yr
20% of 45-65yr
Occur earlier in DM
What should be investigated when a cataract is found?
Fasting plasma glucose
Steroid use
High myopia - nearsightedness
Dystrophia myotonica
What is noted on examination of cataracts?
Loss of red reflex
NB in immature cataracts it may still be present
How are cataracts classified?
Nuclear
Cortical
Posteriorsubcapsular
Describe nuclear cataracts
Affects centre of lens - affects the lens refractive index and can cause more myopia (nearsightedness) at first or temporarily improve reading
With time, lens turns more yellow / brown and clouds vision
Common in old age
Describe cortical cataracts
Affects the edges of the lens - wedge shaped opacities which have milder effects on vision
Describe posterior subcapsular cataracts
Progress faster and cause the classic glare from bright sunlight and lights whilst driving at night, even when visual acuity is only mildly affected
Small, opaque area area at the back of the lens
How do cataracts present?
Blurred vision
Unilateral = often unnoticed but loss of steropsis affects distance judgement
Bilateral = gradual painless loss of vision (frequent changes of glasses as refraction changes)
+/- dazzle esp in sunlight
+/- monocular diplopia (double vision resolves when affected eye covered)
Difficulty driving at night and haloes around street lights
How may cataracts present in children?
Squint
White pupil
Nystagmus / amblyopia
What is stereopsis?
Depth perception due to the slightly different perspectives that each individual eye has
What is amblyopia?
aka lazy eye
Decreased visual acuity
What is the management of cataracts?
Mydriatic drops (dilate pupils) / sunglasses can help
Surgery if large effect on ADL or cannot read number plate from 20m (and a driver)
Treat congenital cataracts surgically ASAP to prevent amblyopia - must be corrected within latent period of visual development (1st 6 weeks of life)
What surgery is offered for cataracts?
Day case using LA with small incision
Lens removed by phacoemulsion - broken up by US then aspirated into a cannula
Incision enlarged and an artificial lens (eg perspex, acrylic or silicon) implanted
Abx and anti-inflammatory drops used 3-6wks post op
2% get serious complications
How can cataracts be prevented?
Sunglasses
Decrease oxidative stress eg with antioxidants
Stop smoking / alcohol
What are some causes of cataracts?
Congenital <1% eg TORCH esp rubella
Acquired 99% eg age, DM, renal insufficiency, wilson’s, drugs induced eg glucocorticoids or anticholinesterases, sunlight, infections
What is keratitis?
Corneal inflammation
Identified by a white area on the cornea indicating a collection of white cells in corneal tissue
Keratoconjunctivitis = conjunctivitis with associated corneal involvemet
What is a corneal abrasion? How may it present?
An epithelial breach
Causing pain, photophobia +/- decreased vision
Non infective corneal ulcers eg accidental scratches / contact lenses
Infective
What are some infective causes of corneal abrasion?
Bacterial (beware pseudomonas - may progress rapidly) Herpetic Fungal - candida, aspergillus Protozoal = acanthamoeba Basculitis eg in RA
How can a corneal lesion be identified?
Use fluorescein drops and blue light on a slit lamp
Corneal lesions stain green - drops are orange and become yellow on contact with eye
Always invert the eye lid to look for FB
How can a simple corneal abrasion be managed (non infective)?
Chlorampenicol ointment
+/- cycloplegia (relax ciliary muscle relieving pain)
What is a corneal abrasion vs an ulcer?
How is corneal ulcer managed?
Abrasion = scratch to epithelium but does not go through the Bowman’s layer underneath (an ulcer does)
Refer to specialist
Remove contact lenses
Diagnostic smear / gram stain and scrape
What causes dendritic corneal ulcers?
HSV type 1
How do dendritic ulcers present?
Pain
Photophobia
Watering
What is the management of dendritic ulcers?
Aciclovir 3% eye ointment 5 x daily
Corneal transplants for those with significant visual impairment due to scarring
What is the management of corneal ulcers?
Until cultures known, alternative chloramphenicol drops (for gram +ve) with ofloxacin (or gram -ve) drops
or
0.3% cefuroxime drops with gentamicin drops
admit in DM, immunosuppressed or pt won’t manage drops
Steroid drops can be added once recovery has begun
How are ofloxacin drops given?
Up to one drop every 15min
What are some risks of steroid eye drops?
Associated with increasing IOP (which can be risky in glaucoma pt) and cataract formation
Can potentially prolong the course of viral conjunctivitis by increasing the latency of adenovirus
Careful not to miss corneal ulcer as steroids can propagate the ulcer causing corneal melt and blindness
What is a stye?
General term for inflammatory lid swelling, could be:
Hordeolum externum
Hordeolum internum
Chalazion
Meibomian cyst
What is a hordeolum externum?
Abscess or infection, usually staph, in a lash follicle
These can also involve the glands of Moll (sweat glands) and of Zeis (sebum glands attached directly to lash follicles)
Can cause much inflammation
How is hordeolum externum treated?
Apply hot compress for 5-10 mins several times each day until the stye resolves
What is a hordeolum internum?
An abscess of the Meibomiam glands
Open onto conjunctiva and cause less local reaction but leave a residual swelling = chalazion or a meibomiam cyst when they subside
Which styes point inwards and outwards?
Hordeolum externum = ‘outwards’
Hordeolum internum = ‘inwards’
What may cause vision to decrease in hordeolum externum?
Corneal flattening (rare)
How are residual swellings managed in hordeolum internum?
Incision and curettage under LA
What is lid inflammation called?
Blepharitis
What can cause blepharitis?
Staph infection
Seborrhoeic dermatitis
Rosacea
How does blepharitis present?
Burning feeling Itching red margins Crusting = staph infection Gunking = secretions from Meibomian glands Loss of eyelashes Frothy tears
What is the management of blepharitis?
Good eyelid hygiene - use a cotton bud and baby shampoo diluted 1:10 with warm water and clean along the lid margins twice a day
In children with blepharokeratitis, consider oral erythromycin too
What is an entropion?
Lid inturning
What commonly causes an entropion?
Degeneration of lower (rarely upper) lid fascial attachments and their muscles
Rare <40yr
Inturned eyelashes irritate the cornea
What is the management of entropion?
Taping the lower eyelids to the cheek or botulum toxin injection to lower lid gives temporary relief
More lasting relief = surgery
What is an ectropion?
Lower lid eversion causing eye irritation, watering +/- exposure keratitis
What is ectropion associated with?
Older age
Facial palsy
What is the management of an ectropion?
Plastic surgery may correct deformity
If facial palsy is the cause, consider surgical correction with an implant in upper lid to aid closure
What can cause a red eye?
Subconjunctival haemorrhage Inflammation of the sclera - Scleritis and episcleritis Uveitis Anterior uveitis Acute angle closure glaucoma Conjunctivitis
Describe episcleritis vs scleritis
Episcleritis = common, freq self limiting, usually benign
Scleritis = rare, very painful, sight threatening sequelae, strong association to systemic disease
Who commonly gets episcleritis?
70% women
What is the cause of episcleritis?
Mostly idiopathic
Minority of cases associated with underlying disease eg RA
Can be bacterial / viral infections or drug reaction (eg bisphosphonates)
How does episcleritis present?
Acute onset Mild eye pain / irritation Watering Eye redness Unilateral in 70%
NO VISION LOSS
What are the two types of episcleritis?
Simple / diffuse = most common
Nodular / focal = occurs in those with underlying systemic disease, prolonged irritation
How can episcleritis and scleritis be distinguished on examination?
Vasoconstricting eye drops eg phenylephrine 2.5% or 10%
Test whether blood vessels blanch, if they do = superficial vessels meaning episcleritis
If they do not, vessels are deeper = slceritis
What is the management of episcleritis?
Symptomatic - cold compresses, eye lubrication
If persistent - NSAIDS / topical steroids
Treat underlying conditions
What is the prognosis of episcleritis?
Usually spontaneous regression after 1-2 weeks
Can recur every 1-3 months
Rarely progresses to reduce visual acuity - important to rule out other causes that do need treatment eg scleritis, keratitis
What is scleritis?
Generalised inflammation of the sclera itself with oedema to the conjunctiva, sclera thinning and vasculitic changes
Describe the sclera in relation to the cornea
Cornea covers the iris and front of the eye is continuous with the sclera
What is the cause of scleritis?
60% associated with underlying disorders: RA SLE Granulomatosis with polyangitis Polymyositis Gout
What are the different types of scleritis?
Anterior (90%)
Posterior
Necrotising - can cause perforation of sclera
How does scleritis present?
Constant severe dull ache which ‘bores’ into the eye
Ocular movements painful as the muscles insert onto the sclera
Eye redness
Headache
Photophobia +/- vision loss
How is scleritis investigated?
US for posterior scleritis Orbital CT / MRI Systemic disease work up: - RF = RA - ANA = SLE - ANCA = AI vasculitis - HLA typing
How is scleritis managed?
Depends on subtype
Non necrotising anterior = oral NSAIDS +/- PO high dose prednisolone
Posterior scleritis or any evidence of necrotising = systemic steroids
If no response to steroids = systemic immunosuppressives eg azathioprine or methotrexate
Scleral transplantation if impending perforation
What complications are associated with scleritis?
Cataracts
Corneal changes
Glaucoma
Permanent loss of vision
