A canine case of otitis media examined and cured using a video otoscope

Otitis media of the left ear was diagnosed by video otoscopic examination in a 7-year-old, intact male Shih-tzu dog (weight, 5.1 kg), that also had three complex ceruminous adenomas and a Pseudomonas aeruginosa infection in the left ear canal. In such cases, total ear canal ablation is usually required. However, a complete cure was achieved in the present case without total ear canal ablation. The complex ceruminous adenomas were excised using a diode laser, and repeated cleansing of the tympanic cavity and ear canal was implemented using a video otoscope. As a result, the ear canal was closed in a U-form, and the otitis media was cured.     

A retrospective study of 29 cases of otitis media/interna in dairy calves

Epidemiological data, clinical findings, laboratory data, medical imaging, and outcomes were reviewed in 29 dairy calves with otitis media/interna. Age at admission ranged from 1 to 24 wk. The majority of calves were referred during winter. Clinical signs included drooping ear, ptosis, head tilt, abnormal nystagmus, strabismus, dysphagia, regurgitation, stiff neck, opisthotonos, facial hyperesthesia, and purulent aural discharge. Intranasal endoscopic examination of 5 animals revealed nasopharyngeal collapse in 4. Cerebrospinal fluid (CSF) was abnormal in all of 7 cases. Mycoplasma bovis was cultured from all but 1 case with external ear or tympanic bullae samples (n = 12), and Mycoplasma arginini was cultured from the remaining ear sample. Radiographs of the tympanic bullae were performed in 24 calves, tomodensitometry (CT) in 3 calves and ultrasound in 4 calves. According to medical imaging techniques or necropsy, 69% of the cases were classified as chronic. Mean duration of treatment was 23.3 d. The rate of clinical recovery was 75%.     

Bulla curettage for chronic otitis media and interna in dogs.

In a series of 10 clinically affected and 6 clinically normal dogs, the technique of bulla curettage via the external ear canal, after lateral ear resection, was evaluated. In 5 of the 10 dogs with chronic otitis media and interna, the head carriage became normal 2 to 8 weeks after surgery and remained so for at least 18 months; 4 other dogs improved, but the improvement was either temporary or incomplete. In the clinically normal dogs, postsurgical complications were minimal; the tympanic membrane healed completely in 4 of the 6 dogs.     

The method of application and short term results of tympanostomy tubes for the treatment of primary secretory otitis media in three Cavalier King Charles Spaniel dogs

Primary secretory otitis media is an uncommon disease affecting predominantly Cavalier King Charles Spaniel dogs. Current treatment recommendations include repeated manual removal of the mucoid effusion from the tympanic cavity through a myringotomy incision and topical or systemic corticosteroids. The aim of this study was to assess the efficacy of tympanostomy tubes to provide continual tympanic cavity ventilation and drainage for the treatment of primary secretory otitis media in three dogs. Tympanostomy tubes were placed within a myringotomy incision in the pars tensa with the aid of an operating microscope. Clinical signs resolved rapidly in all cases following the procedure and all cases were asymptomatic at the time of follow-up, 8, 6 and 4 months later. Results of this study indicate that tympanostomy tubes provide continual tympanic cavity ventilation and drainage and may be an acceptable alternative to repeated myringotomy for the treatment of primary secretory otitis media.     

Inflammatory middle ear disease of the dog: the pathology of otitis media

Inflammation within the middle ear cavity was recognised in 62 of the ears of 42 dogs with chronic otitis externa and otitis media, after biopsy or necropsy of the middle ear. The pathological changes in the middle ear resembled those reported in other species or after the experimental induction of otitis media in dogs. Perforations in the tympanic membrane were rarely found; on the contrary, the membrane was often thickened. However, the question of whether a perforation in the tympanic membrane must occur before otitis externa can extend to otitis media was not resolved.     

MAGNETIC RESONANCE IMAGING OF OTITIS MEDIA IN A DOG

Otitis media/interna was diagnosed in a 20-month-old German shepherd with the assistance of magnetic resonance (MR) imaging. The MR images were acquired primarily to exclude a brain lesion responsible for vestibular signs. No brain lesion was detected, but obvious signs of chronic changes in the left bulla and external ear canal were confirmed. Thickening of the epithelium and soft tissue surrounding the external ear canal and a laminated appearance of high and low T2 intensities in the tympanic bulla's mucosa were present. The hypointense lines were suspected to be fibrous tissue, indicating chronic changes. This report suggests that MR imaging may serve as a useful imaging tool for otitis media and that it supplies information not obtained with radiography or computed tomography.     

Otitis media in a llama

A 7-month-old female llama was examined because of chronic otitis media and externa of 7 months' duration. Radiographically, the tympanic bullae appeared thicker than normal, and the ventral borders were poorly defined; the left external acoustic meatus (ear canal) appeared to be narrower than the right. The llama was treated with penicillin, and the ear canals were lavaged daily. Contrast radiography was performed on day 15 to determine the shape and size of the ear canals and evaluate the integrity of the tympanic membranes. Contrast medium was visible radiographically in the left tympanic bulla, indicating that the left tympanic membrane was ruptured, but the right tympanic membrane appeared to be intact. The left ear canal was narrower than the right, and the bony ear canals had a well-defined sigmoid shape. The right ear improved with medial treatment alone, but the left ear did not. Therefore, lateral ear canal resection was performed. After surgery, however, exudate was still evident in the left ear canal, and the llama became more lethargic and more reluctant to eat. Lateral bulla osteotomy was attempted, but no purulent material was obtained, and curettage of the bulla resulted in hemorrhage. Because of this and because of the llama's poor physical condition, a decision was made to euthanatize the llama. The sigmoid shape of the bony ear canal and the multicompartmental nature of the tympanic bulla make surgical treatment of otitis media and externa in llamas difficult. Further study of surgical treatments for otitis media in llamas is needed.     

Haemophilus somnus-induced Otitis and Meningitis in a Heifer

The purpose of this report is to describe the lesions of otitis and meningitis associated with Haemophilus somnus infection in a heifer.

The animal was found dead in its pen. At necropsy, there was a severe fibrinopurulent meningitis and suppurative otitis media and interna. The external ear canal contained inspissated debris. Haemophilus somnus was recovered in pure culture from the meningeal exudate. The identity of the organism was confirmed by fluorescent antibody and agar gel immunodiffusion tests. Possible pathogenetic mechanisms are discussed.

     

Otoscopic evaluation of the ear canal.

Otoscopic evaluation of the external ear canal and tympanic membrane is the first diagnostic procedure that should be performed in animals presented with otitis externa. It is important to become familiar with the normal structures of the ear to identify any abnormalities. The video otoscope greatly enhances visualization of these structures as well as aiding in retrieval of foreign bodies, biopsy of masses, and performance of a myringotomy. In some cases, a complete otoscopic examination is not possible on the first visit, and the animal may require anti-inflammatory medications or otic flushing to visualize the entire ear canal as well as the tympanic membrane. The purpose of the otoscopic examination is to address the otitis by evaluating the condition of the ear, looking for any masses or foreign bodies; noting the presence, consistency, and color of any exudate; and evaluating the patency of the tympanic membrane. Once a complete otic evaluation has been performed, additional diagnostics as well as a treatment plan can be formulated.     

Total ear canal ablation combining bulla osteotomy and curettage in dogs with chronic otitis externa and media

Ear canal ablation combining bulla osteotomy and curettage was performed on 44 dogs (n = 72 ears). Indications for the procedure included one or more of the following: chronic nonresponsive otitis externa and/or media (n = 71), tumor in the horizontal portion of the ear canal (n = 1), failed lateral ear resection (n = 11), ossified auricular cartilages secondary to chronic otitis externa (n = 22), failed previous total ear canal ablation (n = 1), and otitis interna (n = 1). In 40 dogs, the surgery was successful in alleviating all clinical signs of otitis externa and media. During the immediate postoperative period, 2 dogs died of causes unrelated to otitis. Complications related to the surgery developed in 9 of the surviving 42 dogs. Ultimately, 95% (40 of the surviving 42) of the dogs were cured by use of this procedure. Surgery successfully resolved the original problems in 97% (66 of 68) of the surgically treated ears of these dogs.     

Chronic Otitis Externa and Otitis Media Treated by Total Ear Canal Ablation and Ventral Bulla Osteotomy in Thirteen Dogs

Ventral bulla osteotomy was combined with total ear canal ablation for the treatment of chronic otitis externa and otitis media in 13 dogs (14 ears) that had been refractory to medical and surgical treatments. Resolution of disease occurred in 11 dogs (12 ears). One dog with unilateral disease underwent a second operation before achieving a good result. One dog was euthanatized for persistent unilateral disease after three surgical procedures. The recurrence of disease in these two dogs (15%) was associated with remnants of ear canal integument within the osseous horizontal canal or tympanic bulla. Facial paralysis occurred in four dogs (31%) and there were no complications in eight dogs (62%). This technique shows no advantage over lateral bulla osteotomy combined with total ear canal ablation for the treatment of chronic otitis externa and otitis media.     

Virtual otoscopy for evaluating the inner ear with a fluid-filled tympanic cavity in dogs

The feasibility of virtual otoscopy (VO) imaging was evaluated in five dogs with experimentally induced otitis media, two control dogs, and two canine patients with otitis media. VO images of the tympanic cavity and ossicles were generated with commercially available software using raw computed tomography (CT) data. Eight out of 10 ears inoculated with pathogen exhibited obvious clinical signs associated with otitis externa. CT images revealed soft tissue density material occupying the tympanic bulla compatible with otitis media in three dogs with experimentally induced otitis media and two patients. No remarkable features were observed on the radiographs. Four different VO views (ear canal, tympanic bulla, eustachian tube, and ossicular chain) were created. Promontory, cochlea window, tympanic, and septum bulla as well as ossicles were easily and clearly distinguished except for the incus and stapes of the clinical patients. VO images were not more suitable than images created with conventional CT for accurately diagnosing otitis media in this study. However, it appears that VO could be more feasible for assessing the complex structure of the inner ear in dogs with fluid-filled tympanic cavities since fluid accumulation within the tympanic bulla did not affect the evaluation of bony tissue in the middle ear on VO images.     

Evaluation of outcome of otitis media after lavage of the tympanic bulla and long-term antimicrobial drug treatment in dogs: 44 cases (1998-2002)

OBJECTIVE: To evaluate the outcome of otitis media in dogs after video-otoscopic lavage of the tympanic bulla and long-term antimicrobial drug treatment. DESIGN: Retrospective study. ANIMALS: 44 dogs with otitis media treated in an academic referral practice. PROCEDURE: Medical records were reviewed for signalment, duration of ear canal disease, previous medical treatments, dermatologic diagnosis, results of cytologic examination and microbial culture of ear canal exudate, findings during video-otoscopy, medical treatment, days to resolution, and maintenance treatments prescribed. Four independent variables (age, duration of ear canal disease prior to referral, use of corticosteroids in treatment regimens, and infection with Pseudomonas aeruginosa) were evaluated statistically for potential influence on time to resolution. RESULTS: Mean +/- SD (range) duration of ear canal disease prior to referral was 24.9 +/- 21.6 (3 to 84) months. Otitis media in 36 dogs resolved after lavage of the tympanic bulla and medical management; mean +/- SD (range) time to resolution was 117 +/- 86.7 (30 to 360) days. Time to resolution was not significantly influenced by any variable evaluated. Three dogs were lost to follow-up, and 4 dogs eventually required surgical intervention. Seven of 36 dogs in which otitis had resolved relapsed; 4 required additional lavage procedures. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicate that lavage of the tympanic bulla combined with medical management is an effective and viable option for treatment of otitis media in dogs.     

Surgical Management of Rabbit Ear Disease

Clinical signs associated with otic disease in rabbits (Oryctolagus cuniculus) are very similar to those demonstrated in dogs and cats. The surgical treatment options to resolve diseases involving the rabbit ear are also comparable with those used for canine and feline species. However, there are key anatomic and physiologic differences that must be accounted for to perform proper surgical treatment on a rabbit that has been diagnosed with ear disease. This article describes the diagnostic and treatment options for otitis externa, otitis media, and otitis interna, with an emphasis on surgical procedures and the important distinctive otic features of the rabbit patient. The ventral bulla osteotomy procedure is recommended for management of otitis media in rabbits without otitis externa. In rabbits with pathology in the external ear canal and the middle ear, total ear canal ablation and lateral bulla osteotomy should be performed. This combined procedure will allow the surgeon to address pathology in both sites, with the ultimate goal of resolution of the underlying disease etiology. Lateral ear canal resection is only appropriate in rabbits with otitis externa without otitis media; however, this surgical procedure may not resolve the otitis externa. If this is a concern, a total ear canal ablation should be done because it offers a greater chance of success.     

A pathologic and bacteriologic study on otitis media in swine.

A pathologic and bacteriologic study on otitis media in swine was performed on 237 swine, ranging in age from 1 day to 1 year. These 237 swine from eight selected farms were slaughtered due to unfavorable prognosis associated with clinical signs of illness. One hundred sixty-three (68.8%) of the 237 swine were found to be affected with otitis, though only a few swine showed clinical signs characteristic of the disease. One hundred fifty-one (63.7%), 53 (22.4%), and 39 (16.5%) had lesions in the middle, external, and internal ear, respectively. Of the 151 cases with otitis media, bilateral and unilateral infection accounted for 114 (75.5%) and 37 (24.5%), respectively. Only 5/53 swine with otitis externa and 6/39 swine with otitis interna failed to show otitis media. All swine with infection in the tympanic cavity had inflammatory lesions in the auditory tube. Examination of the swine grouped by age revealed that, regardless of age, incidence of otitis media was 50-70%. In swine younger than 1 month old, otitis media tended to center on the auditory tube, where a mild infiltration of neutrophils into the mucous membrane was frequent. Thereafter, otitis media increased in degree and extent with age. Forty (26.5%) of the 151 swine affected with otitis media were accompanied by a substantial amount of inflammatory exudate in the tympanic cavity and bulla. Purulent exudate was found in 20/40 (50%) swine. Severe otitis media prevailed in swine between 1 and 4 months of age, showing inspissation of a suppurative exudate in the tympanic cavity and lysis of the underlying osseous wall of the tympanic bulla with subsequent fibrosis.(ABSTRACT TRUNCATED AT 250 WORDS)     

Peripheral vestibular disease associated with cryptococcosis in three cats.

Peripheral vestibular disease referable to otitis media/interna was the main reason for presentation in three cats with cryptococcosis. In two cats, Cryptococcus neoformans var neoformans was isolated from the tympanic bulla. In the remaining cat, otitis media/interna was considered to be secondary to occlusion of the auditory tube by a nasopharyngeal granuloma associated with a C neoformans var gattii infection. This report emphasises the importance of maintaining an index of suspicion for a fungal aetiology in cats with signs of otitis media/interna, particularly in countries with a high prevalence of cryptococcosis. The presence of C neoformans may be overlooked with potentially fatal consequences where only standard methods for bacterial isolation are used to examine samples obtained from the middle ear.     

Chronic otitis externa/media with total ear canal ablation and bulla curettage in a North American bison (Bison bison).

An adult female North American bison (Bison bison) with a chronic otitis externa/media of the right ear was examined because of a 4-mo history of intermittent anorexia, apparent painful behavior, and auricular discharge from the right ear. Computerized tomography (CT) demonstrated osteolysis of the tympanic, petrous, and squamous aspects of the temporal bone with soft tissue replacement and sclerosis of the right bulla. A total ear canal ablation with bulla curettage was performed, and cefazolin-impregnated polymethacrylate beads were left within the right bulla and the remnant temporal bone. Six months after the surgery, the bison had no clinical signs of otitis media.     

Clinical Techniques: When and how to do a myringotomy – a practical guide

A myringotomy is a surgical incision made in the tympanic membrane (TM). This gives access to the middle ear for sampling, flushing and instilling topical therapy. It should be considered whenever the TM is intact and there is clinical evidence of otitis media, abnormal TMs and/or abnormal diagnostic imaging. Samples should be collected for cytological investigation and culture, and then the external ear should be cleaned and dried (if required). Myringotomies should be performed under general anaesthesia and, wherever possible, using a video otoscope; the enhanced view and instrument ports facilitate the technique and reduce the risk of complications. The myringotomy incision should be made in the caudoventral quadrant of the TM using an appropriately sized urinary catheter to collect samples and flush the middle ear cavity. A thorough understanding of the anatomy, technique and potential ototoxicity of topical therapy is needed to minimize the risk of neurological and other complications. The TM usually heals within 35 days if kept free of infection.     

Nasopharyngeal polyps in cats

Nasopharyngeal polyps are non-neoplastic, inflammatory growths that arise from the middle ear or the eustachian tube and extend into the pharynx. The exact etiology of nasopharyngeal polyps is unclear; proposed etiologies include a response to chronic upper respiratory tract infection, chronic otitis media, ascending infection from the nasopharynx, or a congenital origin. Clinical signs usually relate to obstruction of the nasopharynx, with Horner's syndrome and head tilt being consistent with otitis media and otitis interna, respectively. Diagnostic tools include digital or visual examination above the soft palate, flexible fiberoptic caudal rhinoscopy, radiography, computed tomography, and magnetic resonance imaging. Ventral bulla osteotomy combined with traction removal of the polyp is the recommended treatment, although traction only followed by prednisolone therapy can be considered in some cases, especially when there is no evidence of otitis media.     

Ear cleaning: the UK and US perspective

Ear cleaning helps maintain the normal otic environment and is important in the treatment of otitis. Over cleaning, however, may trigger otitis through maceration of the epidermal lining. Simple manual cleaning is useful for routine cleansing but doesn't remove tightly adherent debris. Bulb syringes are more vigorous but may damage the ear in inexperienced hands. Devices using mains water pressure or dental machines are also available. Thorough cleaning of the ear canals and middle ear cavity can only be achieved by retrograde flushing using specially adapted catheters, feeding tubes or video otoscopes under anaesthesia. Myringotomy, inspection and cleaning of the middle should be performed if the tympanic membrane appears abnormal. There are a wide variety of cleaning fluids available. Ceruminolytics soften and dissolve cerumen to facilitate cleaning. Surfactants emulsify debris, breaking it up and keeping it in solution. Astringents dry the ear canal surface, preventing maceration. Maintaining a low pH and incorporating antimicrobial agents can inhibit microbial proliferation and glucocorticoids can be used to reduce inflammation. Adverse effects and contraindications following ear cleaning can include maceration, contact reactions, otitis media, ear canal avulsion, vestibular syndrome, Horner's syndrome, facial nerve paralysis and deafness. Care should be exercised in selecting cleaning fluids if the tympanic membranes are ruptured.