Use of a mucosal advancement flap for the treatment of nasopharyngeal stenosis in a cat

Investigation of a retroesophagoscopic approach to nasopharyngoscopy as an alternative to the conventional retroflexed endoscopic approach for selected indications in feline cadavers and client-owned cats

OBJECTIVE

To describe a retroesophagoscopic approach (ROSA) to nasopharyngoscopy and compare it with the conventional retroflexed endoscopic approach (REA).

ANIMALS

36 feline cadavers and 2 client-owned cats with nasopharyngeal disorders.

PROCEDURES

36 veterinarians participated in the experimental portion of the study involving feline cadavers. Each veterinarian performed the ROSA and REA to nasopharyngoscopy on a feline cadaver once, attempting to identify and biopsy 2 landmarks (soft palate and choanae) with each approach while time was recorded. Numeric scales were used to measure perceived ease of use and image quality for both techniques. Data were compared between approaches by an independent statistician. The ROSA approach was also used as part of the diagnostic workup for the 2 client-owned cats.

RESULTS

35 of the 36 (97%) veterinarians were able to identify and biopsy both landmarks using the ROSA, whereas 21 (58%) veterinarians were able to visualize both landmarks using the REA and 19 (53%) successfully biopsied the landmarks. Image quality for the soft palate was scored higher with the ROSA (median score, 7.5/10) than with the REA (4.5/10). The ROSA was fast and easy to perform. This approach was also successfully performed in the 2 client-owned cats with nasopharyngeal disorders, with no complications reported.

CONCLUSIONS AND CLINICAL RELEVANCE

The ROSA was found to be a fast, effective, and easy alternative endoscopic technique for assessment of the nasopharynx in cats. This approach may allow use of various instruments that could be relevant for interventional procedures. However, the ROSA was also invasive and should be considered for diagnostic and therapeutic purposes for selected indications only when REA is unsuccessful.

Fluoroscopic evaluation of laryngopharyngeal anatomic variations attributable to head posture in dogs

OBJECTIVE

To fluoroscopically evaluate the effects of head posture and sedation on the laryngopharyngeal anatomic structures in dogs.

ANIMALS

6 clinically normal Beagles (mean age, 6.2 years; mean weight, 10.4 kg).

PROCEDURES

Each dog was sedated and placed in right lateral recumbency, and fluoroscopic examinations were performed with flexed, neutral, and extended head postures (FHP, NHP, and EHP, respectively). During 3 respiratory cycles, the angle between the basisphenoid bone and nasopharyngeal dorsal border (ABN), thickness of the soft palate, diameter of the nasopharyngeal lumen (DNL), overlapping length between the epiglottis and soft palate, and distance between the epiglottis and tympanic bulla (DET) were measured and percentage difference in the DNL (PDNLD) during a respiratory cycle was calculated.

RESULTS

For the FHP, NHP, and EHP, median ABN was 91.50° (interquartile range [IQR], 86.75° to 95.00°), 125.00° (IQR, 124.50° to 125.50°), and 160.00° (IQR, 160.00° to 163.50°), respectively, with no significant differences between ABN and posture angle. For the FHP, median DNL and DET significantly decreased, compared with values for the NHP, and median thickness of the soft palette significantly increased. For the EHP, the minimal DNL and DET significantly increased, and the median overlapping length between the epiglottis and soft palate significantly decreased, compared with values for the NHP. The PDNLD significantly increased and decreased with FHP and EHP, respectively, compared with the PDNLD with NHP. Sedation did not affect upper airway structure changes.

CONCLUSIONS AND CLINICAL RELEVANCE

Results indicated that head posture significantly affected the laryngopharyngeal structures in dogs. Fluoroscopic examination of the upper respiratory tract of a dog should be performed with an NHP to minimize posture-induced changes in measurements.

Extended palatoplasty as surgical treatment for nasopharyngeal stenosis in six cats

OBJECTIVE

To describe the use of extended palatoplasty as treatment of caudal nasopharyngeal stenosis in cats.

MATERIALS AND METHODS

CT was used to confirm the diagnosis in cats with clinical signs consistent with nasopharyngeal stenosis. Extended palatoplasty rostral to the tonsils using monopolar electrocautery allowed simultaneous removal of the caudal soft palate together with the stenotic area. Cats were re-evaluated 2 weeks postoperatively. Telephone interview was used to obtain long-term follow-up.

RESULTS

Six domestic shorthair cats were diagnosed with nasopharyngeal stenosis, with clinical signs of snoring (n=4), stertor (n=4), nasal discharge (n=3) and sneezing (n=1). CT scan identified a soft-tissue stricture at the level of the caudal nasopharynx in all cats. Other abnormalities included bilateral rhinitis (n=3), retropharyngeal adenomegaly (n=2), unilateral sinusitis (n=1) and bilateral otitis externa with unilateral otitis media (n=1). Excision of the caudal soft palate and the entire stenotic soft-tissue membrane was successful in all six cats. No pre-, intra- or postoperative complications were observed. Short-term outcome revealed clinical improvement in all cases. Long-term outcome revealed no recurrence of clinical signs in four cats. In one cat, occasional sneezing was reported. One cat died 1 month postoperatively for reasons unrelated to the respiratory condition.

CLINICAL SIGNIFICANCE

Extended palatoplasty was an effective technique to treat caudal nasopharyngeal stenosis and provide improvement of clinical signs without postoperative complications in all cases.

Balloon dilation for the treatment of nasopharyngeal stenosis in seven cats

Objectives

The objective of this study was to evaluate the effectiveness of balloon dilation for the treatment of nasopharyngeal stenosis in cats.

Methods

The medical records of seven cats with nasopharyngeal stenosis treated with balloon dilation were reviewed. The most common presenting clinical signs included upper airway noise, sneezing, nasal and/or ocular discharge. All seven cats were confirmed to have nasopharyngeal stenosis via nasopharyngeal endoscopy and were treated with balloon dilation under endoscopic guidance.

Results

All seven cats had acceptable short-term control (median 14 days) of clinical signs after the procedure. Two of six cats had successful long-term control (median 34 days) of clinical signs after one balloon dilation and an additional 2/6 cats had acceptable long-term control of clinical signs after a second balloon dilation procedure. The most significant complication of balloon dilation was the recurrence of stenosis.

Conclusions and relevance

The findings of this study indicate that balloon dilation is a safe and effective treatment option for the relief of clinical signs associated with nasopharyngeal stenosis in cats. Multiple procedures may be necessary for the best chance of long-term success.

Signalment, clinical presentation, concurrent diseases, and diagnostic findings in 28 dogs with dynamic pharyngeal collapse (2008-2013)

Background

Most information about pharyngeal collapse in dogs is anecdotal and extrapolated from human medicine. A single case report describing dynamic pharyngeal collapse in a cat has been published, but there is no literature describing this disease process in dogs.

Objective

To describe the signalment, clinical presentation, concurrent disease processes, and imaging findings of a population of client‐owned dogs with pharyngeal collapse.

Animals

Twenty‐eight client‐owned dogs with pharyngeal collapse.

Methods

Radiology reports of dogs for which fluoroscopy of the respiratory system was performed were reviewed retrospectively. Patients with a fluoroscopic diagnosis of pharyngeal collapse were included in the study population. Data regarding clinical signs, diagnostic, and pathologic findings were evaluated.

Results

Twenty‐eight dogs met the inclusion criteria. The median age of affected patients was 6.6 years, whereas median body condition score was 7/9. The most common clinical signs were coughing (n = 20) and stertor (n = 5). In 27 of 28 cases, a concurrent or previously diagnosed cardiopulmonary disorder was detected. The most common concurrent disease processes were mainstem bronchi collapse (n = 18), tracheal collapse (n = 17), and brachycephalic airway syndrome (n = 8). Fluoroscopy identified complete pharyngeal collapse in 20 of 28 dogs.

Conclusions

Pharyngeal collapse is a complex disease process that likely is secondary to long‐term negative pressure gradients and anatomic and functional abnormalities. Based on the findings of this study, pharyngeal fluoroscopy may be useful diagnostic test in patients with suspected tracheal and mainstem bronchial collapse to identify concurrent pharyngeal collapse.

Treatment of acquired nasopharyngeal stenosis using a removable silicone stent

The aim of this prospective study was to characterise patient characteristics and the histories of cats with acquired nasopharyngeal stenosis (ANS), and to describe the use of a removable silicone stent for treatment. ANS was diagnosed in 15 cats with clinical signs present for a median of 4 months. Clinical signs included stertor and inspiratory difficulty, nasal discharge, sneezing, dysphagia, regurgitation, vomiting and anorexia. Radiographs revealed a dorsal deviation or deformation of the caudal part of the soft palate in 10 of the cats, a soft tissue density across the cranial nasopharynx in four and no abnormality in one. The stenosis was initially dilated with a Kelly forceps in 10 of the cats and by balloon dilatation in five. A segment of a 24 Fr silicone thoracic catheter was used for the stent in five cats; in the other 10 cats a segment of a 28 Fr catheter was used. The stent was removed after 3 weeks in 12 cats and after 4 weeks in the other three. Endoscopy revealed an adequate nasopharyngeal diameter in all of the cats. At both 3 and 10 months after surgery the response was considered to be satisfactory, with complete resolution of clinical signs in 14 cats and improvement in the remaining cat. The treatment of ANS by stenosis dilatation followed by temporary stenting with a silicone stent is a rapid, safe, economical and effective procedure.

Nasopharyngeal disease in cats: 2. Specific conditions and their management

PRACTICAL RELEVANCE

Nasopharyngeal disease is a common presenting problem in feline medicine.

CLINICAL CHALLENGES

The management of feline nasopharyngeal disease can be challenging at a number of levels. In many cases, a specific diagnosis may remain elusive. Some conditions may not be curable so owners need to understand the requirement for long-term management. In addition, treatment may be compromised by poor patient compliance.

AUDIENCE

This review, which is directed at any clinicians involved in the management of cats with nasopharyngeal disease, discusses acute rhinitis (cat 'flu) and a variety of conditions causing chronic rhinosinusitis/chronic nasopharyngeal disease. The intention is to assist treatment decision making by reviewing the most appropriate therapies from the options available for these patients.

EVIDENCE BASE

The information presented in this article is based on peer-reviewed publications and the clinical experience of the authors.

Bilateral choanal atresia in a cat

A 7-month-old female spayed domestic shorthair cat was presented for investigation of stertor, open mouth breathing without apparent distress, and chronic bilateral nasal discharge that was unresponsive to antibiotics. Complete bilateral bony choanal atresia was diagnosed with computed tomography and nasopharyngoscopy. Choanal atresia is an uncommon congenital condition where the choana (nasal passage into the nasopharynx) is blocked by abnormal bone or soft tissue uni- or bilaterally. The cat’s clinical signs improved dramatically immediately after trans-palatal surgical correction. Post-surgical complications included the development of nasopharyngeal scar tissue and subsequent stenosis, persistent right-sided nasal discharge, and permanent damage to the right eye (blindness and cataract formation). Nasopharyngeal stenosis was managed with repeated balloon dilatations and temporary stenting, and the owner reported an excellent quality of life at 8-month follow-up. Bilateral bony choanal atresia has not been previously reported in cats. Uni- or bilateral choanal atresia should be considered in young cats presenting with refractory stertor, chronic nasal discharge, and/or open mouth breathing.

Nasopharyngeal stenosis with concurrent hiatal hernia and megaesophagus in an 8-year-old cat

A case of nasopharyngeal stenosis with secondary hiatal hernia is described. An 8-year-old castrated male domestic shorthair cat was referred for a chronic upper respiratory problem and presumptive vomiting. Despite conservative management by the primary care veterinarian, the cat's condition progressed. The cat was presented to an emergency facility prior to referral to a specialty hospital. On presentation, inspiratory stridor was evident. Thoracic radiography revealed a hiatal hernia. Computed tomography indicated pharyngeal edema and probable nasopharyngeal stenosis. Endoscopy confirmed the presence of nasopharyngeal stenosis consistent with either stricture or choanal atresia. Balloon dilation of the choana was performed. The hiatal hernia regressed spontaneously post-resolution of the nasopharyngeal stenosis. The cat remained asymptomatic at recheck 3 months later.

Amelioration of acquired nasopharyngeal stenosis, with bilateral Z-pharyngoplasty

Nasopharyngeal stenosis as a postoperative complication following pharyngeal surgery (tonsillectomy/adenoidectomy) is rare and may be difficult to treat. All patients with severe nasopharyngeal stenosis treated at UCLA with a bilateral Z-pharyngoplasty procedure from 1999 to 2006 were studied (n = 6). Degree of pharyngeal stenosis preoperatively and following a bilateral Z-pharyngoplasty was graded 0-4 based on (1) symptomatology (snoring, hyponasal speech, difficulty with nasal breathing, difficulty breathing during exercise, obstructive sleep apnea, daytime fatigue, anosmia, rhinorrea, dysphagia, or difficulty in blowing nose) and (2) measurement of stricture at the time of direct nasolaryngoscopy. Nasopharyngeal stenosis after pharyngeal surgery (adenotonsillectomy--67%, uvuloplasty--17%, pharyngoplasty--17%) failed to be alleviated by a mean of 2.3 procedures (kenalog injection or scar excision) and required corrective bilateral Z-pharyngoplasty a mean of 9.2 months after the original surgery. Symptomatic grading of the nasopharyngeal stenosis improved from a mean score of 3.3 (severe stenosis) preoperatively to a score of 0.2 (minimal to no stenosis) in follow-up. Endoscopic stricture measurement improved from 6.1 x 6.3 mm preoperatively to 28.1 x 39.3 mm in follow-up. Bilateral Z-pharyngoplasty was effective in alleviating severe postsurgical nasopharyngeal stenosis.

Stenotic nasopharyngeal dysgenesis in the dachshund: seven cases (2002-2004)

Medical records of seven dachshunds with congenital nasopharyngeal stenosis from abnormally thickened palatopharyngeal muscles were reviewed. The intrapharyngeal ostium in all cases consisted of only a narrow slit. Dogs were presented with various clinical signs--the most common being dyspnea, expiratory cheek puff, salivation, pharyngeal dysphagia, oral dysphagia (to a lesser extent), and macroglossia. Diagnostic procedures included direct pharyngeal inspection, pharyngeal and thoracic radiography, fluoroscopy, lingual ultrasonography, biopsies in two dogs, and a postmortem examination in one dog. Diagnoses were readily made with radiographs and visual examinations. Macroglossia was confirmed with transcutaneous ultrasonography or a transmandibular finger test.

Investigation of nasal disease in the cat--a retrospective study of 77 cases

A retrospective study was undertaken to determine the prevalence of different diseases in cats referred for investigation of chronic nasal disease, to identify historical, clinical and diagnostic features which may assist in making a diagnosis, and to provide information pertaining to outcome in these cats. Diagnoses included neoplasia (30 cases), chronic rhinitis (27), foreign body (8), nasopharyngeal stenosis (5), Actinomyces infection (2), nasal polyps (2), stenotic nares (2), and rhinitis subsequent to trauma (1). The most common neoplasia was lymphosarcoma (21 cases), with a median survival of 98 days for cats treated with multiagent chemotherapy. Cats with neoplasia were older on average than the other cats, and were more likely to be dyspnoeic and have a haemorrhagic and/or unilateral nasal discharge than cats with chronic rhinitis. Cats with neoplasia were more likely to have radiographic evidence of nasal turbinate destruction, septal changes, or severe increases in soft tissue density than cats with chronic rhinitis. It was unusual for cats with diseases other than neoplasia to be euthanased as a result of their nasal disease.

Balloon dilatation of nasopharyngeal stenosis in a cat

A cat was diagnosed with nasopharyngeal stenosis on the basis of clinical signs, survey and contrast radiography, endoscopy and magnetic resonance imaging. The condition was successfully managed with repeated balloon dilatation.

Balloon dilation for the treatment of chronic recurrent nasopharyngeal stenosis in a cat

Balloon dilation was used for the treatment of a recurrent nasopharyngeal stenosis in a cat with chronic stertorous breathing. The procedure was performed on three occasions at intervals of three and four months using a 15 mm valvuloplasty balloon dilation catheter. After the first dilation, clinical signs reappeared within two weeks due to re-stenosis. After the second dilation, all signs of nasopharyngeal disease disappeared, and did not recur. Endoscopic re-evaluation after four months revealed a markedly enlarged nasopharyngeal opening with some degree of stenosis, and a third balloon dilation was performed. Five months later, the cat remained without clinical signs, although some recurrence of the stenosis was visible endoscopically. Complications occurred after the first dilation, and included mild conchal necrosis and transient mucopurulent discharge. Balloon dilation is a minimally invasive technique and can be a successful procedure for treating nasopharyngeal stenosis in cats.