STEEPLECHASE - Special Senses EAR Flashcards
Otodectes cynotis
Otodectes cynotis
Demodex canis
Demodex canis / cati
Sarcoptes scabiei var. canis - mites found on deep skin scrapes - burrowing mite
Sarcoptes scabiei var. canis - mites found on deep skin scrapes - burrowing mite
Foreign body
Acute atopy
Acute atopy
Chronic atopy
Chronic atopy
Cutaneous adverse food reaction (CAFR)
Contact hypersensitivity - erythema often seen dorsally and ventrally to external acoustic meatus (where medication is common in contact w/ skin of ear)
Keratinisation disorders - endocrine disease (hypothyroidism, hyperadrenocorticism, sex hormone dermatoses); sebaceous adenitis; primary idiopathic seborrhoea
Feline ceruminous cystomatosis
Feline nasopharyngeal (inflammatory) polyp - non-neoplastic feline ear mass
Feline nasopharyngeal (inflammatory) polyp - non-neoplastic feline ear mass
Canine juvenile sterile granulomatous dermatitis and lymphadenitis (puppy strangles)
Canine juvenile sterile granulomatous dermatitis and lymphadenitis (puppy strangles)
Multifocal lesion of erythema, plaques + patches of alopecia due to dermatophytosis
Erythematous macules due to canine distemper virus
Aural haematoma - dog bites, pruritus, blunt trauma
Aural haematoma
Squamous cell carcinoma - due to actinic dermatitis
Bacterial cocci
Streptococcus spp.
Biofilm
Biofilm cytology
Malassezia dermatitis
Roughened mucosa due to Malassezia dermatitis
Progressive pathologic change
Progressive pathologic change - epithelial folds = fibrosis + creates niche for microbes
Progressive pathologic change
Equine aural plaques (ear pinna papilloma) - perpetuating factor of otitis externa/media
Normal hairy ear canal of labradoodle - confirmation predisposition to otitis
Aural haematoma - serosanguinous fluid formed haemorrhage distends the pinna and creates a cavity between the skin and cartilage of pinna
External ear
Ear canal - covered by squamous epithelium
Middle ear
Give the (single word) morphologic diagnosis for this image of a dog. The radiograph is from the same animal. What is going on here?
Anotia - absence of an ear
Microtia - growth disorder, ear has not formed properly and is small compared to what would be considered normal for the individual/species
Polyotia - growth disorder, too many (poly-) ears/pinnae
Tick infestation - covering pinnae of dog
Aural plaques/papillomas on ear of horse - also known as…
[Equine ear papillomas
Papillary acanthoma
Hyperplastic dermatitis of the ear
Ear fungus]
Aural haematoma
Dermatophilus congolensis in a kid, bacterial infection (rain scald)
Dermatophilus congolensis, ‘rain scald’
Squamous cell carcinoma + also has secondary pinnal necrosis as well as a consequence of neoplastic process
This image shows cells collected from an FNA in a cat’s ear. What would your diagnosis be based on the morphology of the cells?
SCC - these cells are polygonal, closely associated with each other with a large cytoplasm. Some have large nuclei with prominent nucleoli. As a result, we can conclude they are a malignant population of epithelial cells; in this case SCC.
Mast cell tumour
Erythema - due to otitis externa
Bilateral suppurative otitis externa (Cow)
Aural inflammatory polyp
Polyp
Aural melanoma
Canine leproid granuloma
Granulomatous response of canine leproid granuloma
The morphological diagnosis for these two animals is dermal alopecia (multifocal to coalescing areas of dermatitis with some crusting and scaling). What is the likely cause?
Dermatophytosis
Dentigerous cyst / temporal odontomas in a horse
Fistulous tract of dentigerous cyst
Skin flaking and alopecia (likely secondary otitis externa) of dentigerous cyst
Alopecia and crusting (likely secondary) of dentigerous cyst
Swelling (‘tumour’) of dentigerous cyst
Morphological diagnosis
Proliferative necrotising otitis externa
Proliferative necrotising otitis externa
Feline ceruminous cystomatosis
Cat’s middle ear
Mammonongamus auris (ear-worm)
Aural necrosis
External ear - pinna
Middle ear
Feline nasopharyngeal polyp - no drainage of eustachian tubes
Choroid plexus carcinoma - tumour originating from the fourth ventricle
Lesions resulting in loss of inhibitory influence of cerebrum, cause paradoxical contralateral postural deficits, still a form of central vestibular diseases
Choroid plexus tumour w/ cyst associated
Bilateral vestibular disease - thiamine deficiency (vit B1, energy cofactor metabolism in brain)
Erythema of ear pinna in allergic dog
Severe exudative otitis externa
Ceruminous otitis, dog w/ hypothyroidism
Pemphigus foliaceus on pinna
Staphylococcal infection
Narrowing of external ear w/ early glandular hyperplasia
Ulcerated canal and ruptured tympanic mem in chronic case of Pseudomonas infection
Hairy ear canal - dog
Partial occlusion of canal by ceruminous gland adenoma
Ceruminous gland hyperplasia in chronic otitis
Severe ceruminous gland hyperplasia, not amendable w/ medical therapy
Infection in middle ear, can ascend through a ruptured tympanic membrane to perpetuate otitis externa
Many neutrophils w/ hypersegmented nuclei, phagocytosed bacteria with some neutrophils (cocci), sometimes in pairs + tetrads, possibly staphylococcus spp. but chain seen so could be Streptococcus spp.
Unipolar budding yeast, most common yeast in dogs = Malassezia pachydermatis, some are free and others are associated with keratinocytes
Small no. neutrophils w/ hypersegmented nuclei at the periphery, phagocytosis not seen, predominance of rod-shaped bacteria, could be Pseudomonas, Proteus, E. coli, Klebsiella, some cocci present (top middle)
Mild erythema of pinna and ear canal entrance, dark brown coffee ground-like ceruminous discharge visible, white specks visible within cerumen, ear mites (Otodectes cynotis)
Purulent discharge present at external auditory meatus and horizontal canal, small ulcerations visible on the concave pinna (near external auditory meatus and horizontal canal)
Tumour present on the cranial lateral pinna covered in crust, doesn’t appear to be occluding ear canal entrance
Cobblestone appearance to ear canal entrance, may represent ceruminous gland hyperplasia.
Tympanic mem - inflamed and abnormal, opaque and difficult to distinguish the pars tensa from pars intermedia
Head of malleus cannot be seen
Cytology - squames + numerous rod bacteria
Ceruminous otitis, ear canal is erythematous. oedema of ear canal and ceruminous gland hyperplasia (cobblestone appearance), ear canal very narrowed distally, making assessment of tympanic mem impossible
Cytology - numerous yeast likely to be Malassezia pachydermatis + squame (yeasts adhered to), further cytology of unstained wax to assess for Otodectes mites, cultures not necessary as yeast already identified + further investigations for cutaneous adverse food reaction if other evidence atopic disease
Alopecic left pinna, hyperpigmented + linear ulceration covered w/ crust running from an eroded pinnal edge along medial pinna surface, right pinna eroded (more extensively than left), alopecia of right pinna mild + a lot of crusting but no ulceration visible, biopsy - CS/history suggestive of vasculitis/vasculopathy - alopecia and erosions along pinnal margin secondary to ischaemic damage to ear tip skin (lack of collateral blood supply)
Identify the pars flaccida, why is the pars flaccida dilated?
Increased pressure in the middle ear can cause the pars flaccida to bulge into horizontal ear canal
Epithelial fold formation, stenosis, ceruminous gland hyperplasia, ulceration (bleeding)
Erythema and mild ulceration of horizontal canal, abnormal opaque tympanic mem, hole in tympanic mem is from myringotomy during ear flush procedure using ear canal
Opaque tympanic mem, erythema and ulceration, purulent discharge
Erythema, stenosis (unable to assess tympanic mem), ulceration, macerated epithelium (white areas), purulent discharge
Erythema, stenosis, ulceration, sebaceous gland hyperplasia (small white spots)
Severe stenosis
Ceruminolith
Brown ceruminous discharge, Malassezia pachydermatis
Purulent discharge, thicker on left than right, due to bacterial infection e.g. Staphylococcus pseudintermedius, Pseudomonas
Macerated epithelium
What is the predisposing factor present?
Hirsuitism - excessive hair present, miniature poodle
Cotton fibre from an ear bud
Why are there air bubbles seen at the bottom of the ear canal during the ear flush?
Tympanic membrane is ruptured and air from the middle ear is bubbling into the external ear canal
Very stenotic ear canal, 2mm diameter catheter
Flushing mucopurulent discharge from middle ear
Profuse slimy purulent discharge in dog’s ear due to biofilm production
Gram-negative bacteria - pseudomonas aeruginosa, Klebsiella, E. coli, Proteus
Glue ear / 1^y secretory otitis media, changes to tympanic mem, bulging + large, mucoid fluid accumulation within middle ear, loss of ability of eustachian tube to drain mucus -> degree of hearing loss + balance issues
