Evaluation of aural masses submitted as inflammatory polyps in 20 dogs (2000-2020).

BACKGROUND: Canine non-neoplastic aural polypoid masses (APMs) are uncommon, with few published studies. OBJECTIVES: The aim of this retrospective study was to characterise the clinical presentation, diagnostic imaging and histopathological results for APMs submitted as aural inflammatory polyps (AIPs). ANIMALS: Twenty dogs with APMs evaluated at a veterinary teaching hospital. MATERIALS AND METHODS: Cases were selected by searching computerised medical records from 2000 to 2020, using keywords 'canine', 'aural/otic polyp' and 'aural/otic inflammatory mass'. Histological samples and medical records were reviewed. RESULTS: In 14 of 20 dogs, external ear canal masses were characterised by keratinised squamous epithelium with or without adnexa. Tympanic bulla origin was confirmed in four of 20 dogs by the presence of cuboidal to ciliated columnar epithelium, with or without squamous epithelium. The site of origin could not be determined in two dogs. Diagnostic imaging (MRI or CT) confirmed APM presence in 14 of 20 dogs. Otitis media was diagnosed in four of four tympanic bulla APMs and seven of 13 ear canal APMs. In 18 of 20 dogs, debulking, traction avulsion, and total ear canal ablation and bulla osteotomy led to APM resolution in two of eight, four of six and four of four dogs, respectively. CONCLUSIONS AND CLINICAL RELEVANCE: Type of epithelium was a key feature in determining the APM origin, and interpretation in conjunction with video otoscopy and diagnostic imaging was crucial. Canine APMs more commonly arose from the ear canal. Tympanic bulla APMs and APMs of undetermined origin were comparable to feline AIPs. Regardless of APM origin site, debulking had the greatest likelihood of recurrence.

Retrospective study identifying risk factors for dacryocystitis in pet rabbits.

BACKGROUND: Dacryocystitis has been suggested to be a relatively common condition in pet rabbits and is often associated with concurrent disease. The aim of this study was to investigate potential risk factors associated with dacryocystitis in a pet rabbit population. METHODS: A retrospective review of medical records from all rabbit cases evaluated at a single first opinion/referral UK exotics clinic between 2015 and 2018 was performed. RESULTS: Dacryocystitis was identified in 55 of 821 rabbits (6.70%) examined over the study period. Of those rabbits with dacryocystitis, dental disease was found in 24 rabbits (45%), respiratory disease in 20 rabbits (38%), aural disease in seven rabbits (13%) and concurrent ocular disorders in 15 rabbits (23%). Breed status was found to be a significant risk factor, with Lionhead/Lionhead cross and Dwarf Lop/Dwarf Lop cross rabbits being more likely to have dacryocystitis. CONCLUSION: These results suggest that a breed predisposition for dacryocystitis may exist, particularly for the popular Lionhead and Dwarf Lop rabbits, and veterinarians should advise clients on this accordingly.

Surgical creation of multiple drainage holes versus local injection of corticosteroids for treatment of aural hematomas in dogs: 51 dogs with 71 aural hematomas (2000-2017).

OBJECTIVE: To investigate the outcome of surgical creation of multiple drainage holes (MDHs) versus local corticosteroid injection (LCI) for treatment of aural hematomas (AHs) in dogs and identify risk factors for recurrence and development of new AHs. ANIMALS: 51 dogs with 71 AHs. PROCEDURES: Medical records were reviewed, and information on signalment, clinical findings, and outcome was recorded. Recurrence was defined as development of an AH at the primary site after the first month of treatment. Development of a new AH was defined as an AH occurring at a site different from the treated site. RESULTS: The recurrence rate after the first month of treatment was significantly higher following the LCI procedure (17/48 AHs [33%]) than after the MDH procedure (1/24 AHs [4%]). The odds of recurrence increased as the numbers of LCI in the first month increased (OR, 2.414). Recurrent AHs after LCI resolved with additional LCIs; only 1 AH (2%) required a change to MDHs. No recurrence was observed after the eighth month, and the cosmetic results were good. Sixteen of 51 (31%) dogs had multiple or new AHs. The risk of new AHs was higher in Golden Retrievers and Labrador Retrievers and in dogs with allergic dermatitis. CONCLUSIONS AND CLINICAL RELEVANCE: Long-term outcomes suggested that both creation of MDHs and LCI can be therapeutic options for dogs with AHs. However, the risk of new AH development should be considered, especially in retriever breeds and dogs with allergic dermatitis.

Surgical management of bilateral ear pinna lesions associated with traumatic aural hematoma in a 3-day-old goat kid.

Background: Aural hematomas are not uncommon in ruminants' clinical practice; however, there is a lack of information regarding their management in newborn ruminants, especially for complicated cases with rupture of the hematoma and secondary ear pinna necrosis. Case Description: A 3-day-old orphan goat kid was admitted due to swelling on the left ear pinna and trauma on the right pina caused by biting by other goats. The swelling on the left ear which was located at the convex surface was soft, painless, and fluid-filled, suggestive of aural hematoma located at the convex surface. The right pinna was swollen, bleeding, and extremely painful at palpation. The skin was necrotized at the distal 2/3rd of the convex surface and the 1/2 of the concave surface. Underneath the necrotized skin of the convex surface, blood, and blood clots were trapped, and there was a pocket between the remaining normal skin and the cartilage indicating possible rupture of aural hematoma. The kid was surgically treated under general anesthesia with xylazine and ketamine. The aural hematoma was drained by the convex surface using a Penrose tube after flushing the cavity with 2 mg dexamethasone. The trauma of the right pinna was left to heal by secondary intention after resection of all necrotized, edematous tissues, and blood clots. Post-surgery, the animal was treated with parenteral antibiotic administration and daily application of a topical antiseptic solution. The Penrose tube was removed after 5 days, and the animal recovered uneventfully. Conclusions: The present case indicates that aural hematoma can occur in newborn goat kids secondary to ear pinna biting and might evolve to pinna necrosis. In addition, tube drainage after flushing the cavity with corticosteroids appears to be an effective treatment approach without requiring bandaging post-operatively.

Reporting the epidemiology of aural haematoma in dogs and proposing a novel aetiopathogenetic pathway.

To evaluate the incidence and risk factors for aural haematoma in dogs under primary veterinary care in the UK. A cohort study design. Dogs diagnosed with aural haematoma during 2016 were identified from the VetCompass database. Univariable and multivariable logistic regression modelling were used for risk factor analysis. There were 2,249/905,554 dogs diagnosed with aural haematoma during 2016. The estimated one-year incidence risk for aural haematoma was 0.25% (95% confidence interval 0.24-0.26). After accounting for confounding factors, 14 breeds showed increased odds and 20 breeds showed reduced odds of aural haematoma compared with crossbred dogs. Breeds with the highest odds included Bull Terrier (OR 7.42, 95% confidence interval 4.39-12.54), Saint Bernard (OR 7.28, 95% confidence interval 3.58-14.81) and French Bulldog (OR 6.95, 95% confidence interval 5.55-8.70). Increasing age, increasing bodyweight and breeds with V-shaped drop and semi-erect ear carriage also showed increased odds of aural haematoma. Associations between ear carriage within breeds and the risk of aural haematoma suggest that trauma along the line of cartilage folding within V-shaped and semi-erect ears may trigger aural haematoma. New knowledge of key breed predispositions will contribute to improved breed health control strategies.

Clinical features, treatment, and outcome of aural hematomas in horses: 7 cases (2008-2019).

OBJECTIVE: To characterize the clinical features, treatment, and outcome of aural hematomas in horses. ANIMALS: 7 horses with 1 or 2 aural hematomas (8 ears in total) treated at a veterinary teaching hospital in 2008 through 2019. PROCEDURES: Data retrieved from medical records included signalment, pertinent historical information, clinical signs, diagnostic procedures (including dermatologic assessment), and treatments. Case outcome was determined from documentation in the medical record or via telephone communication with owners or referring veterinarians. RESULTS: 3 horses were presented after recurrence of aural hematoma following treatment by the referring veterinarian. Four horses had a history of allergic skin disease prior to aural hematoma development. Most (6/7) horses were unilaterally affected. Diagnostic assessments included otoscopic evaluation (3 horses), ultrasonography (3 horses), cytologic examination of ear canal swab samples (3 horses), and histologic examination of a pinnal biopsy specimen (1 horse). Of the 8 pinnae, 2 were treated by nonsurgical needle drainage (1 with concurrent corticosteroid injection) and the remaining 6 underwent surgical incision and placement of compressive sutures. Follow-up information was available for 6 horses, and all affected pinnae were fibrotic with 4 horses having permanent drooping of the pinna. One horse developed a hematoma in the contralateral pinna 1 year after hospital discharge. CONCLUSIONS AND CLINICAL RELEVANCE: Equine aural hematoma is a rare condition. The main principle of treatment is drainage, and treatment options commonly used in small animal practice can be successfully applied in horses. Permanent changes in the cosmetic appearance of the pinna are likely to develop owing to secondary fibrosis.

The use of near infrared fluorescence imaging with indocyanine green for vascular visualization in caudal auricular flaps in two cats.

OBJECTIVES: To describe the use of near infrared fluorescence (NIRF) imaging with indocyanine green (ICG) for vascular visualization in two caudal auricular axial pattern flaps (APF). ANIMALS: Two client-owned cats with upper eyelid masses. STUDY DESIGN: Clinical case report. METHODS: Wide surgical excision with enucleation was performed by using a caudal auricular APF for closure. Flap margins and perforating artery location were approximated with anatomical landmarks. The caudal auricular artery origin was then visualized percutaneously by using an exoscope with NIRF camera and light source after a single 2.5-mg dose of IV ICG. Margins were adjusted as required. The flaps were routinely elevated with continued intraoperative visualization of the artery and rotated to complete closure. RESULTS: After IV ICG administration, fluorescence was initially visualized after 15 to 18 seconds and remained visible for up to 26 minutes. The achieved visualization led to flap margin adjustments in cat 1. Both cats recovered with minimal flap congestion, excellent hair regrowth, and no long-term complications (>186 days). Cat 1 experienced 100% flap survival. Cat 2 experienced 10% partial thickness flap necrosis, but revision was not required, and the flap was healed at recheck 85 days postoperatively. CONCLUSION: The use of ICG for APF vessel visualization prior to and during flap elevation resulted in transcutaneous visualization of the perforating vessel and improved awareness of vessel location intraoperatively. These two cats experienced excellent flap survival without major complications. This report highlights the potential benefits of ICG NIRF in APF for animals undergoing reconstructive surgery.

On the nature of canine aural haematoma and its treatment with continuous vacuum drainage.

OBJECTIVES: To evaluate continuous vacuum drainage from the convex side of the pinna for surgical treatment of aural haematoma in dogs. To investigate aural haematoma fluid and cartilage samples harvested during surgery in an attempt to elucidate the etiopathogenesis of the lesion. MATERIALS AND METHODS: Ten client-owned dogs with aural haematoma were treated by convex-side vacuum drainage using different types of vacuum drains and containers and were followed-up for at least 6 months. Systemic blood samples and aural haematoma fluids were analysed for biochemical, haematologic and electrophoretic content. Cartilage samples were examined histologically. RESULTS: Nine of the 10 dogs were successfully treated without recurrence at 6 months postoperatively and with excellent cosmetic results. In one case, infection required early drain removal and delayed healing was associated with wrinkling of the pinna. Fluid sample analysis suggested that "aural haematoma" contains a transudate that accumulates within a cartilage-lined cavity. Histologic examination of the tissue samples revealed clefts of the pinna cartilage, with the luminal surface often lined with granulation tissue. Fluids and cartilage lacked evidence of inflammation. CLINICAL SIGNIFICANCE: This technique was characterised by patient comfort, tolerance of drains, absence of dressings and good cosmetic outcome. The results of fluid analysis suggest that the term "aural seroma" would be more appropriate for this condition.

EAR MITES, OTODECTES CYNOTIS, ON WILD FOXES (PSEUDALOPEX SPP.) IN CHILE.

We found the ear mite parasite (Otodectes cynotis; Acari: Psoroptidae) in two distant insular endangered fox populations in Chile. We identified O. cynotis in both the Darwin's fox (Pseudalopex fulvipes) from Chiloé and the Fuegian culpeo (Pseudalopex culpaeus lycoides) in Tierra del Fuego. These populations are approximately 2,000 km apart. Infestation rates were high for both endemic foxes: 76% (19/25) of Darwin's foxes were affected, and 73% (11/15) of Fuegian culpeos had ear mites. Two Darwin's foxes had abundant ear discharge, and one of these also exhibited secondary infections of Morganella morganii and Geotrichum sp. fungi. Mites were characterized molecularly as Otodectes spp. for the Fuegian culpeo samples. Genetic analyses of two mites found the O. cynotis genotype I, as well as what appeared to be a new allele sequence for O. cynotis. These results confirmed the hypothesis of a worldwide distribution species of ear mite. Introduced chilla foxes (Pseudalopex griseus; n=11) on Tierra del Fuego Island and domestic dogs (Canis lupus familiaris; n=379) from both islands were also sampled, but they showed no signs of infection. Our findings provided insight into the genetic diversity, the origins, and the possible impact of this globally distributed mite on endemic free-ranging populations of foxes.

Otoscopy and aural cytological findings in a population of rescue cats and cases in a referral small animal hospital in England and Wales.

OBJECTIVES: Otitis externa is seen clinically in cats, although studies investigating this condition within the UK are lacking. The objective of this study was to investigate the prevalence of Otodectes cynotis mites and microbial infection in the ear canals of cats in various rescue centres and a referral hospital. METHODS: Otoscopy was performed in 332 cats. Otoscopic findings were noted, including the gross visualisation of Otodectes species. A sample of cerumen was collected for cytological evaluation and a cerumen smear for detection of Otodectes mites if there was a large amount of aural exudate present. RESULTS: O cynotis infestation was noted in 3/341 cats (0.9%, 95% confidence interval [CI] 0.3-2.6). A total of 129/341 (37.8%; 95% CI 32.7-43.0) cats were found to have Malassezia species within one or both ears. Bacteria were found unilaterally in 9/341 (2.6%; 95% CI 1.4-4.9) cats. Analysis of the cytological findings showed an increased likelihood for Malassezia species to be present as age increased (n = 293; Pearson r = 0.204, P <0.001). There was also an increased likelihood of finding Malassezia species in both ears if found within one ear (n = 327; r = 0.499, P <0.001). There was a positive correlation between the number of Malassezia organisms and the quantity of aural exudate (n = 338; r = 0.778, P <0.001). Cats in which Otodectes species infestation were noted (n = 3) had moderate or large quantities of cerumen. CONCLUSIONS AND RELEVANCE: This study shows that there was a low prevalence of O cynotis in this cohort of cats. In normal cats it was not unusual to find Malassezia microorganisms upon aural cytology, bacteria were noted far less frequently and in two cats this was associated with underlying anatomical pathology.

Lop-eared rabbits have more aural and dental problems than erect-eared rabbits: a rescue population study.

This research aimed to assess whether rabbits having lop ears, an artificially selected conformation, compromises welfare. We investigated the occurrence of aural and dental pathology in lop-eared compared with erect-eared rabbits. Thirty rabbits (15 lop-eared and 15 erect-eared) from a rabbit-only rescue shelter were examined. An otoscope was used to visualise the ear canals and mouth. Samples were taken from each ear to examine for mites, bacteria and yeast. Medical records were also examined. Lop-eared rabbits showed statistically significantly more frequent ear canal stenosis, higher scores of cerumen and erythema and more frequent potential pain response during ear examination, compared with erect-eared rabbits. We also found statistically significantly more frequent incisor pathology, molar overgrowth, molar sharpness, molar spurs and history of veterinary dental treatment in lop-eared compared with erect-eared rabbits. The effect sizes were often large. Age was not statistically significant between the lop-eared and erect-eared rabbit groups. Thus, lop-eared rabbits were at an increased risk of aural and dental pathology in this study. This brings into debate the ethics of breeding and buying lop-eared rabbits, as they are more likely to suffer conditions that negatively impact welfare, such as pain, and potentially deafness and difficulty eating.

Comparison of complications and outcome following unilateral, staged bilateral, and single-stage bilateral ventral bulla osteotomy in cats.

OBJECTIVE: To compare complications and outcome following unilateral, staged bilateral, and single-stage bilateral ventral bulla osteotomy (VBO) in cats. ANIMALS: 282 client-owned cats treated by VBO at 25 veterinary referral and academic hospitals from 2005 through 2016. PROCEDURES: Medical records of cats were reviewed to collect information on signalment, clinical signs, diagnostic test results, surgical and postoperative management details, complications (anesthetic, surgical, and postoperative), and outcome. Associations were evaluated among selected variables. RESULTS: Unilateral, staged bilateral, and single-stage bilateral VBO was performed in 211, 7, and 64 cats, respectively, representing 289 separate procedures. Eighteen (9%), 2 (29%), and 30 (47%) of these cats, respectively, had postoperative respiratory complications. Cats treated with single-stage bilateral VBO were significantly more likely to have severe respiratory complications and surgery-related death than cats treated with other VBO procedures. Overall, 68.2% (n = 197) of the 289 procedures were associated with Horner syndrome (19.4% permanently), 30.1% (87) with head tilt (22.1% permanently), 13.5% (39) with facial nerve paralysis (8.0% permanently), and 6.2% (18) with local disease recurrence. Cats with (vs without) Horner syndrome, head tilt, and facial nerve paralysis before VBO had 2.6, 3.3, and 5.6 times the odds, respectively, of having these conditions permanently. CONCLUSIONS AND CLINICAL RELEVANCE: Findings suggested that staged bilateral VBO should be recommended over single-stage bilateral VBO for cats with bilateral middle ear disease. Cats with Horner syndrome, head tilt, and facial nerve paralysis before surgery were more likely to have these conditions permanently following surgery than were cats without these conditions.

Computed tomographic grading of middle ear disease in domestic rabbits (Oryctolagus cuniculi).

Ear disease, involving the middle and external ear, is commonly reported in pet rabbits, with lop-eared breeds predisposed. CT is the most reliable imaging modality for identifying otitis media (OM) in rabbits. This study aimed to develop a CT-based grading scale to classify the severity of CT changes in rabbits with presumed OM. Three observers independently reviewed CT images of 36 rabbits with OM. For both OM and material within the external ear canal, a grade of I to IV was used, (I=mild, IV=severe disease) and the level of agreement between reviewers was statistically evaluated. The study demonstrated that grades from the three reviewers showed a strong level of interobserver agreement. Comparisons between clinical signs and CT grade were also evaluated. Rabbits with grade IV OM had a high grade of material in the external ear canal. A high proportion of rabbits (83 per cent) underwent CT scanning conscious, demonstrating that diagnostic quality CT images are achievable without the need for anaesthetic intervention, minimising patient risk. This novel CT-based grading scale provides a methodology to correlate grade of disease with clinical signs, ear canal cytology, predisposing factors, treatment options and outcomes for rabbits with ear disease.

In vitro antimicrobial activity of topical otological antimicrobials and Tris-EDTA against resistant Staphylococcus pseudintermedius and Pseudomonas aeruginosa isolates from dogs.

BACKGROUND: The value of susceptibility tests for the selection of topical otological antimicrobial agents is unclear. Laboratories test antibiotic concentrations substantially lower than concentrations supplied in topical formulations. Additionally, microbiological consensus statements are not available for topical antimicrobials. HYPOTHESIS/OBJECTIVES: The primary aim of this study was to measure the minimum inhibitory and bactericidal concentrations of enrofloxacin, gentamicin, marbofloxacin, neomycin, orbifloxacin, polymyxin B and silver sulfadiazine from concentrations available in otological formulations (COF) to 1:59,000 dilution. The secondary aim was to evaluate the effect of Tris-EDTA in conjunction with these antimicrobial agents. METHODS AND MATERIALS: Twenty resistant clinical isolates [Staphylococcus pseudintermedius (n = 10) and Pseudomonas aeruginosa (n = 10)] were tested by broth microdilution using a concentrated inoculum (3.75 × 107 cfu/mL). RESULTS: Concentrations available in otological formulations were at least 26× greater than the MICs for S. pseudintermedius and P. aeruginosa. COFs of polymyxin B and SSD were 27× greater than the MBCs for P. aeruginosa, whereas all other antimicrobial COFs were equal to or less than the MBCs for both organisms. Tris-EDTA significantly reduced the MICs of all antimicrobials, except with SSD for P. aeruginosa, and it significantly increased the MIC of SSD for S. pseudintermedius. CONCLUSIONS AND CLINICAL IMPORTANCE: Further studies are warranted to validate the present results in vivo. COFs are inhibitory and less likely bactericidal, with few exceptions, against resistant strains of these organisms. Tris-EDTA may be advantageous for P. aeruginosa whereas no additional benefit is afforded against S. pseudintermedius. Susceptibility tests may not be useful for the selection of topical otological antimicrobial agents.

Comparison of two techniques for transpharyngeal endoscopic auditory tube diverticulotomy in the horse.

Auditory tube diverticula, also known as guttural pouches, are naturally occurring dilations of the auditory tube in horses that communicate with the nasopharynx through a small ostium. Infection and select other conditions can result in inflammation and narrowing of the nasopharyngeal ostium, which prevents drainage of fluid or egress of air and can lead to persistent infection or guttural pouch tympany. Auditory tube diverticulotomy allows continuous egress from the auditory tube diverticula and is a feature of disease treatment in horses, in which medical treatment alone is not successful. Transpharyngeal endoscopic auditory tube diverticulotomy was performed using a diode laser either at a single dorsal pharyngeal recess location or bilaterally caudal to the nasopharyngeal ostium in 10 horse head specimens. Both methods resulted in clear communication between the nasopharynx and auditory tube diverticula. Diverticulotomy performed in the dorsal pharyngeal recess required less laser energy and activation time and had a shorter surgical duration than diverticulotomy performed caudal to the nasopharyngeal ostium. Further study related to the clinical application of both techniques is warranted.

Quantifying parasite presence in relation to biological parameters of harbour porpoises Phocoena phocoena stranded on the Dutch coast.

Harbour porpoises are often found to be infected by endoparasites in several organs including the lungs and stomach as well as the heart, liver and ears. Nevertheless there is still little knowledge about the impact, ecology, transmission, and virulence of these parasitic infections. Here, we profile the presence of parasites in 4 frequently infected organs (lungs, stomach, liver and ears) in relation to biological parameters of harbour porpoises stranded along the Dutch coastline between December 2008 and December 2013. We found that parasites were common, with prevalence of 68% in lungs, 74.4% in ears, 26% in stomach and 23.5% in liver. We used generalised linear models to further quantify parasite presence in relation to biological data gathered during necropsy (sex, body length and nutritive condition). Body length (used as a proxy for age) was significant in explaining parasite presence for all organs with increasing probability of having the parasite with increasing body length. For the parasitic infections in the ears and stomach the nutritive condition was an additional significant factor, with a higher probability of parasite presence in porpoises in a poorer nutritive condition. The results of this study can be used as a baseline for assessing parasite presence in harbour porpoises and are a first step towards linking parasite infections to basic biological data gathered during necropsy.

RECURRENT EAR MITE (OTODECTES CYNOTIS) INFESTATION IN THREE RELATED GROUPS OF PATAGONIAN CAVIES (DOLICHOTIS PATAGONUM).

: Two of three groups of Patagonian cavies ( Dolichotis patagonum ) contracted Otodectes cynotis infestations after exposure to mite-infested feral cats. Otodectes cynotis infestations were initially identified in 9 of 10 cavies in group 1. Multiple feral cats with O. cynotis infestations were observed in the vicinity of the Patagonian cavies and were subsequently removed. The Patagonian cavies were initially treated with ivermectin (0.4 mg/kg s.q.) every 2 wk, but ivermectin was discontinued after the third treatment due to injury to one of the Patagonian cavies during capture. Sixteen months after initial treatment, clinical signs of scratching the pinnae, hemorrhagic lesions on the ear margins, head shaking, and O. cynotis mites in the auricular canal were again noted in all Patagonian cavies in group 1. Repeated administration of ivermectin (0.4 mg/kg s.q. every 2 wk for three treatments) failed to eliminate the mites in two of the Patagonian cavies. Selamectin administered (20 mg/kg, topically between the shoulder blades) to all Patagonian cavies eliminated the mite infestation after a single application. The Patagonian cavies remained O. cynotis mite free for 2 yr, until males (group 2) and females (group 3) were separated for population control. Three months after separation, 8 of the 12 females in group 3 again were infestated with O. cynotis mites. Feral cats with O. cynotis infestations were again noted in the vicinity of group 3. A single dose of selamectin applied topically eliminated all mites in all treated Patagonian cavies. Group 2 was not exposed to feral cats and remained mite free.