Otitis Flashcards
What is the number one cause of ear infections
allergies
T/F: inflammation cause otitis and not infection
True
What is the pathogenesis of otitis externa
1) Primary cause
2) Inflammation
3) then infection
when examining ears, you need to be
parallel to the ear canal
What is lowest point in the external ear canal
intertragic incisure
What is the goal of ear visualization
see the tympanic membrane
What do you do for aural hematomas
1 mg/kg pred PO q24h for 1-2 weeks
50% success rate with this strategy, without scarring
What is the starting point of otoscopic examination
intertragic incisure
How do you get around the transition between the horizontal canal and the vertical canal (luminal
pull the ear out towards you
How do you get proper visualization of ear canal
-Extend ear
-Head down and rostral
-Table top recommendended
-assistant hold
if ear pain, avoid the luminal fold
What might cause opaque tympanic membrane
ear inflammation
Do you pluck ear hairs?
no- do not pluck hair
causes inflammation
What are the different otoscopes
Operating scope
Pneumatic Scope
video otoscopy
T/F: if a patient has a dilated pars flaccida you dont have to be concerned
true
T/F: visible wax accumulation in ear is normal
False- sign of inflammation
What type of glands produce ear wax
modified apocrine glands
concretions of wax and debris that fill the horizontal canal, in front of the tympanum.
ceruminolith
What is the key to treatment, prevention, and control of otitis
inflammation
a single episode of otitis is likely a
flare of secondary infection resulting from ongoing primary inflammation, and is likely to recur
Acutely treating otitis will result in
temporary improvement, but further episodes in the future
What are the 4 causes of Otitis *
1) Allergy
2) Something in the ear (foreign body, mass, ectoparasite)
3) Endocrinology
4) Immune disease
T/F: conformation causes ear disease
False
T/F: hair causes otitis
False
T/F: swimming causes otitis
False
“It cant be allergies because otitis is unilateral”
False
Primary otitis inflammation is often complicated by
secondary infection (yeast/bacteria)
What does ear cytology tell you
1) Organism population- greater or fewer
2) Changing organisms? rods? cocci? yeast?
3) Dying organisms- yeast will break down or you can assess for yeast resistance
4) No organisms- drug reaction? inflammation
5) Pairing with culture
What are indications for otitis culture
1) Otitis media/interna (bc its 8-12 week tx)
2) Cant medicate topically (compliance)
3) Rods (Pseudomonas aerginosa)
4) Topical medications ineffection
-Breakpoints designed for systemic antibiotics
may not be accurate for topicals
5) Middle ear vs external ear canal sample?
6) Cytology usually sifficient for initial cases
What should do you prior to treating otitis media/interna
culture because the treatment is 8-12 weeks
If you see rods on ear cytology, what should you do?
culture! - likely Pseudomonas otitis
How does Pseudomonas otitis rupture the tympanum
they are ulcerative (produce proteolytic enzymes)
Why should you never empirically treat Pseudomonas otitis
because they are typically multi-drug resistant
Fluoroquinolones or aminoglycosides are empric choices
do cultures because it makes biofilms
any group of microorganisms in which cells stick to each other and often these cells adhere to a surface
biofilm
How long does Claro last
4 weeks
make sure to flush debris prior and then put claro in it
T/F: there is no reliable treatment for otitis biofilms
True- hard to break up
1ml of ear medication is about ______ drops
20 drops
What can a ruptured tympanic membrane cause
harder for the ear to clean itself
might need to flush more often
T/F: most prescription commercial topicals will resolve acute cases of otitis
True
What medication has no effect for ear inflammation
NSAIDs (steroids work better)
What medications are commonly implicated to cause ototoxicity
Gentamicin, chlorhexidine
but it is idiosyncratic- fast and irreversible
Is cochlear or vestibular ototoxicity more common?
Cochlear (hearing loss) is more common by far
What products are safe for the ears
-Enrofloxacin:Dexamethason SP 1:3
-Miconazole:Dexamethasone SP 1:1
-Enrofloxacin:Miconazole: Dexamethasone SP 1:2:1
-Silver sulfadiazine:saline 1:9
-Cerumene
-Tris-EDTA
-DMSO-Flucinoline (Synotic)
-EpiOtic Advanced
What soften and dissolve cerument to facilitate cleaning
Ceruminolytics
What dries the ear canal surface, preventing maceration
astringents
What are routine ingredients in topical ear medications
1) Ceruminolytics: soften and dissolve cerumen to facilitate cleaning
2) Surfactants emulsify debris, breaking it up and keeping it in solution
3) Astringents dry the ear canal surface, preventing maceration
4) Anti-microbial and anti-inflammatories to control infection/inflammation
5) Non-irritants
good for mild infection or excessive wax accumulation
have little to no anti-inflammatory activity
a small, hammer-shaped bone in the middle ear that plays a key role in hearing
malleus
What makes the tympanic membrane rupture
1) Trauma (CTA, mass polyp) *
2) Pseudomonas (protelytic enzymes)
3) Chronic (proliferative) otitis
4) Otitis media
What is the most common cause of tympanic membrane rupture
Trauma (CTA, mass polyp)
How long does it take to grow a tympanum
30 days
How does the ear clean itself
lateral epithelial migration
moves the epidermal cells (exfoliation) and wav from the inside of the canal to the outside
might stop if masses, inflammation, infection
Accumulations of wax are an indicator of
primary pathology (inflammation, endocrine, etc)
What is an end-stage ear
ear that is refractory to treatment, has perpetuating factors
-Stenosis
-Calcinosis
-Otitis media
-physical obstruction of the canal
-hyperplasia
-fibrosis
swelling can be reverse with steroids but mineralization cannot be removed
How might you fix end-stage ears
1) Rescue medically- takes months and might not work
or
2) Surgically- expensive, invasive, complications
How do you open the ear in complicated ear infections
Steroids
-Oral: pred, dexamethasone, triamcinolone
-Topical (Synotic, dexamethasone SP)
-Injectable?
once daily typically suffices
but if it doesnt resolve in 2 weeks, might need to look at surgical options
Very potent steroids that can be used to open the ear canal in complicated otitis
Synotic
Deep ear cleanings
always recommended
must open the ear first
sedated doesnt work
remove debris (and masses)
better visualization
middle ear cultures
fancy equipment not needed
pressure is needed
CT? for middle and inner ear
biofilms
What is the only way to visualize the middle and inner ear
CT
How do you prevent against otitis
Dirty ears do not exist- find the underlying cause
-address primary cause and secondary infections
-control inflammation
-allergy medications?
-routine treatment with preemptive therapy
-steroids?
in many cases, otitis externa require weekly to monthly maintenance therapy to prevent recurrence
What kind of tissue is the middle ear
ciliated respiratory epithelium
why chronic respiratory disease causes otitis media- sterile fluid build up in the middle ear (bulla)
What are the clinical signs of otitis media
1) Unilateral Xeromycteria (parasympathetic)
2) Horner’s Syndrome (sympathetic)
3) Facial paresis, paralysis (no blink, lip drooping) from facial nerve
What are the clinical signs of otitis interna
-Head tilt
-asymmetrical ataxia
-circling to the side of the lesion
-torticollis
-horizontal or rotatory nystagmus- quick phase from the side of the lesion
-positional ventral strabismus
-deafness
What drugs reverse the signs of vestibular disease
steroids
anti-emetic
Meclizine
What causes otitis media/interna
1) ascending infection from otitis externa
2) abnormal drainage from auditory tube (brachycephalics, PSOM- cavaliers, chronic respiratory cats)
3) Ototoxicity (meds)
4) Neoplasia- adenomas/sarcomas most common, please biopsy
How do you treat otitis media/interna
-Systemic and topical therapy
-Culture (middle ear preferred)- Myringotomy
-Deep (anesthetized) ear cleaning
-8 weeks (deep pyoderma)
-Nerve damage may be permanent
-Vestibular (interna):
1 mg/kg prednislone
Meclizine
Maropitant
Antihistamines?
Benzodiazepines?
How do you treat the vestibular issues with otitis interna
1 mg/kg prednislone
Meclizine
Maropitant
Antihistamines?
Benzodiazepines?
a surgical procedure that involves making an incision in the eardrum to access the middle ear
myringotomy
how do you sample the middle ear
myringotomy
use 5Fr tomcat catheter and sample through the caudal ventral aspect of tensa
push until you hit bone (bulla)
good for biopsy/culture
requires anestesia
How long does it take for the myringotomy perforation to heal
2-4 weeks
non-neoplastic inflammatory, pedunculated masses that arise from the auditory tube or middle ear in cats
feline inflammatory polyps
What is the most common external ear canal mass in the feline patient
Feline inflammatory polyps
the cats middle ear is split into
ventromedial and dorsolateral compartments
dorsolateral connects to the auditory canal
The dorsolateral compartments connects to the _________ which connects to the ________
The dorsolateral compartments connects to the auditory canal which connects to the nasopharynx
Feline inflammatory polyps have what appearance on histopathology
-stratified squamous to ciliated, columnar epithelium
-fibrovascular tissue
-mixed inflammation
What causes Feline inflammatory polyps
Unknown
1) Infectious
-Viral: calicivirus, herpesvirus-1
-Bacterial: mycoplasam, chlamydophilis felis, bartonella
2) Chronic inflammation - persistence of epithelial hypertrophy and submucosal proliferation following inflmmation
3) Congenital/Anatomic: aberrant growths from remnants of branchial arches
What is the typical signalment of Feline inflammatory polyps
no breed or sex predilection
-abyssinian?
any age can be presented but typically <2years
What is the clinical presentation of Feline inflammatory polyps
Variable depending on path of growth
1) Pharyngeal: nasal discharge, sneezing, dyspnea, stridor, dysphagia, stertorous, breathing, phonation change ; possible: cyanosis, syncope
2) Aural: otitis interna, media, externa
interna: head tilt (persistent), nystagmus, ataxia hearing loss
media: horner’s syndrome, facial nerve paralysis
externa: otorrhea, headshaking
secondary infection
What are the signs of Feline inflammatory polyps with growth into the nasopharynx
nasal discharge, sneezing, dyspnea, stridor, dysphagia, stertorous, breathing, phonation change ; possible: cyanosis, syncope
What are the signs of Feline inflammatory polyps with growth into otitis media
Horner’s syndrome
facial nerve paralysis
What are the signs of Feline inflammatory polyps with growth into otitis externa
otorrhea
head shaking
What are differentials for Feline inflammatory polyps
-Upper respiratory tract infections (can be ascending)
-Foreign body
-Neoplasia (adenomas, carcinomas, lymphomas)
-Mycotic disease (cryptococcus)
-Cysts
How do you diagnose Feline inflammatory polyps
1) Visual examination
-Otoscopy
-Endoscopy
-Spay hook retraction
2) Imaging
-Radiography
-CT
-MR
3) Biopsy (otic masses look similar)
T/F: rads are good for diagnosing Feline inflammatory polyps
False
How do you treat Feline inflammatory polyps
1) Surgery -removes all affected tissues
Ventral Bulla Osteotomy (VBO)
-Total ear canal ablation (TECA)
-Lateral ear canal resection
2) Traction-Avulsion/Excision
3) Medical
Antibiotics
Glucocorticoids
What are complications of surgery for Feline inflammatory polyps
Horner’s syndrome (most common)
facial nerve paralysis
hypoglossal nerve damage
ataxia
hearing loss
Ventral Bulla Osteotomy (VBO) is recommended in all cases of
middle ear involvement
What should you do after traction/avulsion
steroids- has recurrence rates similar to VBO (95% success)
