Editorial Type: Respiratory Diseases
 | 
Online Publication Date: 01 Sept 2008

Nasopharyngeal Turbinates in Brachycephalic Dogs and Cats

DVM,
BVSc, MVSc, MS, PhD,
DVM, Diplomate ACVIM, and
DVM, PhD, Diplomate ACVP
Article Category: Other
Page Range: 243 – 249
DOI: 10.5326/0440243
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This retrospective study reports the presence and incidence of nasal turbinates in the nasopharynx (nasopharyngeal turbinates) in a population of brachycephalic dogs and cats exhibiting signs of upper respiratory disease. Medical records were reviewed for 53 brachycephalic dogs and 10 brachycephalic cats undergoing upper airway endoscopy. Nasopharyngeal turbinates were identified in 21% of brachycephalic animals, including 21% of dogs and 20% of cats. Pugs accounted for 32% of all dogs in the study population and 82% of dogs with nasopharyngeal turbinates. The presence of nasopharyngeal turbinates may play a role in upper airway obstruction in the brachycephalic airway syndrome.

Introduction

The brachycephalic airway syndrome (BAS) is a well-known cause of respiratory distress in brachycephalic breeds.1–3 Reported components of BAS include elongation of the soft palate, stenotic nares, everted laryngeal saccules, and hypoplastic trachea.1–7 Stenotic nares and elongation of the soft palate are congenital abnormalities that contribute to upper airway obstruction. Eversion of laryngeal saccules results from negative pressure in the upper airways, and once everted, these saccules may also contribute to the obstruction. Tracheal hypoplasia is a cause of increased airway resistance when present, and, unfortunately, it is not correctable. Chronic airway obstruction in brachycephalic breeds can lead to severe laryngeal edema and, in severe cases, laryngeal collapse.8

In addition to the established components of BAS outlined above, the authors have documented the presence of nasal turbinates protruding caudally from the choanae into the nasopharynx of dogs and cats. The purpose of this study is to report this anatomical finding and its incidence in a population of brachycephalic dogs and cats with signs of upper respiratory disease.

Materials and Methods

Medical records for all brachycephalic dogs and cats undergoing rhinoscopy, bronchoscopy, or laryngoscopy at Wheat Ridge Veterinary Specialists between January 1999 and May 2006 were reviewed. Canine breeds considered to be brachycephalic in this study included the pug, bulldog (English, French, and American), Boston terrier, Pekingese, shih tzu, Lhasa apso, and boxer. Feline breeds considered to be brachycephalic in this study included the Persian and Himalayan. Of the animals considered for the study, those lacking written or photographic evidence of the nasopharynx in the medical record were excluded.

Posterior rhinoscopy was performed under general anesthesia with one of three flexible endoscopes, depending upon the size of the animal.a,b,c Data collected from medical records included age, gender, breed, historical findings, physical examination findings, endoscopic findings, and any histopathology. Age data were compared between animals with and without nasopharyngeal turbinates, and statistical analysis between groups was performed with the use of computer software.d Data between groups were compared by use of a Mann-Whitney U test. For all comparisons, significance was set at a value of P<0.05.

Results

Sixty-three animals were included in this study, including 53 dogs and 10 cats. In the canine population, 32% (17/53) were pugs; 18% (10/53) were English bulldogs; 11% (6/53) were shih tzus; 9% (5/53) were boxers; 6% each (3/53) were American bulldogs, Boston terriers, unspecified bulldogs, and French bulldogs; and 3% each (2/53) were Lhasa apsos and Pekingese. In the feline population, 70% (7/10) were Persians, and 30% (3/10) were Himalayans.

Table 1 summarizes age and gender of the study population. Median age of dogs with nasopharyngeal turbinates was 3 years (range 5 months to 10 years), and median age of dogs without nasopharyngeal turbinates was 5.75 years (range 14 weeks to 16 years). Median age of cats with nasopharyngeal turbinates was 3 years (range 2 to 4 years), and median age of cats without nasopharyngeal turbinates was 11 years (range 6.5 to 16 years). Median ages were compared between dogs with and without nasopharyngeal turbinates. Median ages were not statistically significant between the two groups (P=0.11). Median ages for cats with and without nasopharyngeal turbinates could not be compared due to small sample size; however, the two cats with nasopharyngeal turbinates were 2 and 4 years of age, while the youngest cat without nasopharyngeal turbinates that presented for upper respiratory signs was 6.5 years old.

Forty-six percent (5/11) of dogs with nasopharyngeal turbinates were male (five neutered), and 54% (6/11) were female (three spayed). Forty-three percent (18/42) of dogs without nasopharyngeal turbinates were male (13 neutered), and 57% (24/42) were female (21 spayed). Zero percent of cats with nasopharyngeal turbinates were male, and 100% (2/2) were female (one spayed). Fifty percent (4/8) of cats without nasopharyngeal turbinates were male (all four neutered), and 50% (4/8) were female (three spayed). Statistical analysis was not performed for gender comparisons due to small sample size.

Historical findings were recorded in the medical record for 50 animals in the study population, and results are summarized in Table 2. Historical findings in the study population included nasal congestion or stertor, stridor, decreased airflow, snoring, nasal discharge, sneezing, reverse sneezing, coughing, exercise intolerance, choking, epistaxis, trouble eating, increased respiratory effort, wheezing, vomiting, gagging, and ocular discharge. Statistical comparisons were not attempted based on small sample size.

Physical examination findings were recorded in the medical record for 50 animals in the study population, and Table 3 summarizes these findings. Physical examination findings in the study population included nasal congestion or stertor, stridor, decreased airflow, nasal discharge, wheezing, tracheal sensitivity, sneezing, tracheal collapse, blepharospasm, reverse sneezing, coughing, gagging, obesity, pulmonary crackles, and respiratory distress. Statistical comparisons were not attempted based on small sample size.

Table 4 summarizes findings related to BAS from endoscopic reports. The following BAS-related lesions were identified: stenotic nares, elongated soft palate, everted laryngeal saccules, laryngeal edema, laryngeal collapse, hypoplastic trachea, and nasopharyngeal turbinates. Of the 63 animals in the study, 17% (11/63) had stenotic nares, 62% (39/63) had an elongated soft palate, 60% (38/63) had everted laryngeal saccules, 54% (34/63) had laryngeal edema, 8% (5/63) had laryngeal collapse, and 11% (7/63) had hypoplastic trachea [Table 4].

Twenty-one percent (11/53) of dogs and 20% (2/10) of cats in the study population were noted to have nasopharyngeal turbinates. Eighty-two percent (9/11) of dogs with nasopharyngeal turbinates were pugs. French bulldogs and Pekingese accounted for 9% (1/11) each of the remaining dogs with nasopharyngeal turbinates. In the feline population, 50% (1/2) of cats with nasopharyngeal turbinates were Persian, and 50% (1/2) were Himalayan. Figures 1A through 1D and 2A and 2B show the endoscopic appearance of nasopharyngeal turbinates in selected cases of brachycephalic dogs and brachycephalic cats, respectively. Table 5 summarizes the incidence of nasopharyngeal turbinates in the study population.

In the first dog in which nasopharyngeal turbinates were identified (a 5-year-old, spayed female pug at the time of rhinoscopy), the turbinates were biopsied and examined histologically. The evaluated section consisted of fragments of bone and respiratory epithelium, with a few lymphocytes, plasma cells, and neutrophils present. An excessive amount of dense bone was present within the turbinates, but the bone appeared otherwise histologically normal. The final diagnosis from this biopsy was mild lymphocytic rhinitis with excessive dense bone. Turbinate biopsies were not obtained in any of the other cases. Nasopharyngeal turbinates were not observed in any breeds other than the brachycephalic breeds mentioned above.

Discussion

The unique anatomy of the skull in brachycephalic breeds may provide an explanation for the development of these nasopharyngeal turbinates. The nasal turbinates, along with most other bones of the skull, are derived from the neural crest ectoderm, while other bones of the body are derived from mesoderm. Some bones that are derived from the neural crest, such as the nasal capsule (i.e., maxilla, incisive, palatine, and nasal bones), are formed by membranous ossification and tend to mold closely around the structures they enclose. In addition, these sheathing bones tend to ossify earlier during development (day 28).9 In contrast, the cartilage substrate of endochondral bones continues to grow and ossify beyond the gestational period. Thus, neural crest-derived bones formed by endochondral ossification are less plastic, tending to grow to their full extent. Nasal turbinates are formed by endochondral ossification, and they continue to grow beyond their surroundings.10,11 Therefore, in brachycephalic breeds, the ethmoid turbinate complex may tend to protrude into the nasopharynx because of the limited space in the already ossified nasal capsule.

A few explanations are possible for these structures not having been widely documented to date. The upper airway of a brachycephalic animal is routinely evaluated via direct visualization and without the aid of endoscopy. If a flexible endoscope is not used, the nasopharynx would not be fully evaluated, and, therefore, nasopharyngeal turbinates as a component of BAS would be routinely overlooked. A reasonable assumption would be that nasopharyngeal turbinates may contribute to upper airway obstructions and clinical signs of BAS. Whether specific clinical signs are attributable to nasopharyngeal turbinates is uncertain. As with tracheal hypoplasia, nasopharyngeal turbinates would likely add to the overall increased airway resistance, but surgical correction would be difficult. The authors therefore recommend that in order to fully understand a given animal’s airway lesions, the nasopharynx should be endoscopically examined in all brachycephalic animals undergoing an upper airway evaluation.

Nasopharyngeal turbinates were present in 21% of the authors’ cases during the study period, but the incidence of nasopharyngeal turbinates in the brachycephalic population at large cannot truly be determined from this study. The animals included in the study were those brachycephalic animals that had signs of BAS severe enough to warrant referral, general anesthesia, and endoscopy prior to surgical intervention. In order to ascertain the true incidence of this finding in the brachycephalic population, a prospective study is needed where both clinically normal brachycephalic animals and those affected by BAS would undergo rhinoscopy to screen for nasopharyngeal turbinates—perhaps through routine scoping of all brachycephalic animals undergoing anesthesia for any reason (e.g., airway disease, routine neuters, dental procedures, or other surgeries). In the authors’ experience, nasopharyngeal turbinates have never been noted in any nonbrachycephalic breed.

Interestingly, 82% of the canine cases with nasopharyngeal turbinates were pugs; this finding was similar to that recently reported from Germany.11 However, without a prospective study with a large number of all brachycephalic breeds in the study population, no conclusions can be drawn regarding breed prevalence for nasopharyngeal turbinates because of the small number of individuals representing each breed.

Conclusion

This study has shown that nasopharyngeal turbinates are common in brachycephalic dogs and cats with signs of upper airway disease. The authors believe that because of the approximate 21% incidence of nasopharyngeal turbinates, it is important that the nasopharynx be evaluated for the presence of these structures in all brachycephalic animals undergoing upper airway endoscopy. Further characterization of nasopharyngeal turbinates is required, and the authors recommend more anatomical and histological studies. In addition, computed tomography and three-dimensional imaging studies may further characterize nasopharyngeal turbinates. Prospective studies evaluating incidence, breed prevalence, the contribution of these structures to increased airway resistance, and the clinical signs of BAS are warranted.

a

Storz Veterinary Specialty Fiberscope (60003VB1); Karl Storz Veterinary Endoscopy America, Goleta, CA 93117

b

Storz Canine Bronchoscope (60001VL1); Karl Storz Veterinary Endoscopy America, Goleta, CA 93117

c

Olympus Vet-XP20; Endoscopy Support Services, Inc., Brewster, NY 10509

d

GraphPad Prism, version 4; GraphPad Software, Inc., La Jolla, CA 92037

Table 1 General Characteristics of the Study Population
Table 1
Table 2 Historical Findings of Study Population
Table 2
Table 3 Physical Examination Findings of the Study Population
Table 3
Table 4 Summary of Upper Airway Endoscopic Findings
Table 4
Table 5 Incidence of Nasopharyngeal Turbinates in Brachycephalic Breeds at Wheat Ridge Veterinary Specialists Between 1999 and 2006
Table 5
Figures 1A–1D—. Figure 1A shows a normal nasopharynx in a brachycephalic dog. Figures 1B–1D show the nasopharynxes of brachycephalic dogs with nasopharyngeal turbinates protruding on each side of the vomer bone. In all figures, the image was obtained from retroflexion of an endoscope dorsally and cranially behind the soft palate. The vomer bone is seen dorsally; the soft palate is seen ventrally; and the nasopharynx is seen centrally. The nasopharyngeal turbinates that were encountered appeared either as a fused structure (Figures 1B, 1C) or separate, arising from either choanae (Figure 1D).Figures 1A–1D—. Figure 1A shows a normal nasopharynx in a brachycephalic dog. Figures 1B–1D show the nasopharynxes of brachycephalic dogs with nasopharyngeal turbinates protruding on each side of the vomer bone. In all figures, the image was obtained from retroflexion of an endoscope dorsally and cranially behind the soft palate. The vomer bone is seen dorsally; the soft palate is seen ventrally; and the nasopharynx is seen centrally. The nasopharyngeal turbinates that were encountered appeared either as a fused structure (Figures 1B, 1C) or separate, arising from either choanae (Figure 1D).Figures 1A–1D—. Figure 1A shows a normal nasopharynx in a brachycephalic dog. Figures 1B–1D show the nasopharynxes of brachycephalic dogs with nasopharyngeal turbinates protruding on each side of the vomer bone. In all figures, the image was obtained from retroflexion of an endoscope dorsally and cranially behind the soft palate. The vomer bone is seen dorsally; the soft palate is seen ventrally; and the nasopharynx is seen centrally. The nasopharyngeal turbinates that were encountered appeared either as a fused structure (Figures 1B, 1C) or separate, arising from either choanae (Figure 1D).Figures 1A–1D—. Figure 1A shows a normal nasopharynx in a brachycephalic dog. Figures 1B–1D show the nasopharynxes of brachycephalic dogs with nasopharyngeal turbinates protruding on each side of the vomer bone. In all figures, the image was obtained from retroflexion of an endoscope dorsally and cranially behind the soft palate. The vomer bone is seen dorsally; the soft palate is seen ventrally; and the nasopharynx is seen centrally. The nasopharyngeal turbinates that were encountered appeared either as a fused structure (Figures 1B, 1C) or separate, arising from either choanae (Figure 1D).Figures 1A–1D—. Figure 1A shows a normal nasopharynx in a brachycephalic dog. Figures 1B–1D show the nasopharynxes of brachycephalic dogs with nasopharyngeal turbinates protruding on each side of the vomer bone. In all figures, the image was obtained from retroflexion of an endoscope dorsally and cranially behind the soft palate. The vomer bone is seen dorsally; the soft palate is seen ventrally; and the nasopharynx is seen centrally. The nasopharyngeal turbinates that were encountered appeared either as a fused structure (Figures 1B, 1C) or separate, arising from either choanae (Figure 1D).Figures 1A–1D—. Figure 1A shows a normal nasopharynx in a brachycephalic dog. Figures 1B–1D show the nasopharynxes of brachycephalic dogs with nasopharyngeal turbinates protruding on each side of the vomer bone. In all figures, the image was obtained from retroflexion of an endoscope dorsally and cranially behind the soft palate. The vomer bone is seen dorsally; the soft palate is seen ventrally; and the nasopharynx is seen centrally. The nasopharyngeal turbinates that were encountered appeared either as a fused structure (Figures 1B, 1C) or separate, arising from either choanae (Figure 1D).Figures 1A–1D—. Figure 1A shows a normal nasopharynx in a brachycephalic dog. Figures 1B–1D show the nasopharynxes of brachycephalic dogs with nasopharyngeal turbinates protruding on each side of the vomer bone. In all figures, the image was obtained from retroflexion of an endoscope dorsally and cranially behind the soft palate. The vomer bone is seen dorsally; the soft palate is seen ventrally; and the nasopharynx is seen centrally. The nasopharyngeal turbinates that were encountered appeared either as a fused structure (Figures 1B, 1C) or separate, arising from either choanae (Figure 1D).Figures 1A–1D—. Figure 1A shows a normal nasopharynx in a brachycephalic dog. Figures 1B–1D show the nasopharynxes of brachycephalic dogs with nasopharyngeal turbinates protruding on each side of the vomer bone. In all figures, the image was obtained from retroflexion of an endoscope dorsally and cranially behind the soft palate. The vomer bone is seen dorsally; the soft palate is seen ventrally; and the nasopharynx is seen centrally. The nasopharyngeal turbinates that were encountered appeared either as a fused structure (Figures 1B, 1C) or separate, arising from either choanae (Figure 1D).Figures 1A–1D—. Figure 1A shows a normal nasopharynx in a brachycephalic dog. Figures 1B–1D show the nasopharynxes of brachycephalic dogs with nasopharyngeal turbinates protruding on each side of the vomer bone. In all figures, the image was obtained from retroflexion of an endoscope dorsally and cranially behind the soft palate. The vomer bone is seen dorsally; the soft palate is seen ventrally; and the nasopharynx is seen centrally. The nasopharyngeal turbinates that were encountered appeared either as a fused structure (Figures 1B, 1C) or separate, arising from either choanae (Figure 1D).Figures 1A–1D—. Figure 1A shows a normal nasopharynx in a brachycephalic dog. Figures 1B–1D show the nasopharynxes of brachycephalic dogs with nasopharyngeal turbinates protruding on each side of the vomer bone. In all figures, the image was obtained from retroflexion of an endoscope dorsally and cranially behind the soft palate. The vomer bone is seen dorsally; the soft palate is seen ventrally; and the nasopharynx is seen centrally. The nasopharyngeal turbinates that were encountered appeared either as a fused structure (Figures 1B, 1C) or separate, arising from either choanae (Figure 1D).Figures 1A–1D—. Figure 1A shows a normal nasopharynx in a brachycephalic dog. Figures 1B–1D show the nasopharynxes of brachycephalic dogs with nasopharyngeal turbinates protruding on each side of the vomer bone. In all figures, the image was obtained from retroflexion of an endoscope dorsally and cranially behind the soft palate. The vomer bone is seen dorsally; the soft palate is seen ventrally; and the nasopharynx is seen centrally. The nasopharyngeal turbinates that were encountered appeared either as a fused structure (Figures 1B, 1C) or separate, arising from either choanae (Figure 1D).Figures 1A–1D—. Figure 1A shows a normal nasopharynx in a brachycephalic dog. Figures 1B–1D show the nasopharynxes of brachycephalic dogs with nasopharyngeal turbinates protruding on each side of the vomer bone. In all figures, the image was obtained from retroflexion of an endoscope dorsally and cranially behind the soft palate. The vomer bone is seen dorsally; the soft palate is seen ventrally; and the nasopharynx is seen centrally. The nasopharyngeal turbinates that were encountered appeared either as a fused structure (Figures 1B, 1C) or separate, arising from either choanae (Figure 1D).
Figures 1A–1D—. Figure 1A shows a normal nasopharynx in a brachycephalic dog. Figures 1B–1D show the nasopharynxes of brachycephalic dogs with nasopharyngeal turbinates protruding on each side of the vomer bone. In all figures, the image was obtained from retroflexion of an endoscope dorsally and cranially behind the soft palate. The vomer bone is seen dorsally; the soft palate is seen ventrally; and the nasopharynx is seen centrally. The nasopharyngeal turbinates that were encountered appeared either as a fused structure (Figures 1B, 1C) or separate, arising from either choanae (Figure 1D).Figures 1A–1D—. Figure 1A shows a normal nasopharynx in a brachycephalic dog. Figures 1B–1D show the nasopharynxes of brachycephalic dogs with nasopharyngeal turbinates protruding on each side of the vomer bone. In all figures, the image was obtained from retroflexion of an endoscope dorsally and cranially behind the soft palate. The vomer bone is seen dorsally; the soft palate is seen ventrally; and the nasopharynx is seen centrally. The nasopharyngeal turbinates that were encountered appeared either as a fused structure (Figures 1B, 1C) or separate, arising from either choanae (Figure 1D).Figures 1A–1D—. Figure 1A shows a normal nasopharynx in a brachycephalic dog. Figures 1B–1D show the nasopharynxes of brachycephalic dogs with nasopharyngeal turbinates protruding on each side of the vomer bone. In all figures, the image was obtained from retroflexion of an endoscope dorsally and cranially behind the soft palate. The vomer bone is seen dorsally; the soft palate is seen ventrally; and the nasopharynx is seen centrally. The nasopharyngeal turbinates that were encountered appeared either as a fused structure (Figures 1B, 1C) or separate, arising from either choanae (Figure 1D).Figures 1A–1D—. Figure 1A shows a normal nasopharynx in a brachycephalic dog. Figures 1B–1D show the nasopharynxes of brachycephalic dogs with nasopharyngeal turbinates protruding on each side of the vomer bone. In all figures, the image was obtained from retroflexion of an endoscope dorsally and cranially behind the soft palate. The vomer bone is seen dorsally; the soft palate is seen ventrally; and the nasopharynx is seen centrally. The nasopharyngeal turbinates that were encountered appeared either as a fused structure (Figures 1B, 1C) or separate, arising from either choanae (Figure 1D).Figures 1A–1D—. Figure 1A shows a normal nasopharynx in a brachycephalic dog. Figures 1B–1D show the nasopharynxes of brachycephalic dogs with nasopharyngeal turbinates protruding on each side of the vomer bone. In all figures, the image was obtained from retroflexion of an endoscope dorsally and cranially behind the soft palate. The vomer bone is seen dorsally; the soft palate is seen ventrally; and the nasopharynx is seen centrally. The nasopharyngeal turbinates that were encountered appeared either as a fused structure (Figures 1B, 1C) or separate, arising from either choanae (Figure 1D).Figures 1A–1D—. Figure 1A shows a normal nasopharynx in a brachycephalic dog. Figures 1B–1D show the nasopharynxes of brachycephalic dogs with nasopharyngeal turbinates protruding on each side of the vomer bone. In all figures, the image was obtained from retroflexion of an endoscope dorsally and cranially behind the soft palate. The vomer bone is seen dorsally; the soft palate is seen ventrally; and the nasopharynx is seen centrally. The nasopharyngeal turbinates that were encountered appeared either as a fused structure (Figures 1B, 1C) or separate, arising from either choanae (Figure 1D).Figures 1A–1D—. Figure 1A shows a normal nasopharynx in a brachycephalic dog. Figures 1B–1D show the nasopharynxes of brachycephalic dogs with nasopharyngeal turbinates protruding on each side of the vomer bone. In all figures, the image was obtained from retroflexion of an endoscope dorsally and cranially behind the soft palate. The vomer bone is seen dorsally; the soft palate is seen ventrally; and the nasopharynx is seen centrally. The nasopharyngeal turbinates that were encountered appeared either as a fused structure (Figures 1B, 1C) or separate, arising from either choanae (Figure 1D).Figures 1A–1D—. Figure 1A shows a normal nasopharynx in a brachycephalic dog. Figures 1B–1D show the nasopharynxes of brachycephalic dogs with nasopharyngeal turbinates protruding on each side of the vomer bone. In all figures, the image was obtained from retroflexion of an endoscope dorsally and cranially behind the soft palate. The vomer bone is seen dorsally; the soft palate is seen ventrally; and the nasopharynx is seen centrally. The nasopharyngeal turbinates that were encountered appeared either as a fused structure (Figures 1B, 1C) or separate, arising from either choanae (Figure 1D).Figures 1A–1D—. Figure 1A shows a normal nasopharynx in a brachycephalic dog. Figures 1B–1D show the nasopharynxes of brachycephalic dogs with nasopharyngeal turbinates protruding on each side of the vomer bone. In all figures, the image was obtained from retroflexion of an endoscope dorsally and cranially behind the soft palate. The vomer bone is seen dorsally; the soft palate is seen ventrally; and the nasopharynx is seen centrally. The nasopharyngeal turbinates that were encountered appeared either as a fused structure (Figures 1B, 1C) or separate, arising from either choanae (Figure 1D).Figures 1A–1D—. Figure 1A shows a normal nasopharynx in a brachycephalic dog. Figures 1B–1D show the nasopharynxes of brachycephalic dogs with nasopharyngeal turbinates protruding on each side of the vomer bone. In all figures, the image was obtained from retroflexion of an endoscope dorsally and cranially behind the soft palate. The vomer bone is seen dorsally; the soft palate is seen ventrally; and the nasopharynx is seen centrally. The nasopharyngeal turbinates that were encountered appeared either as a fused structure (Figures 1B, 1C) or separate, arising from either choanae (Figure 1D).Figures 1A–1D—. Figure 1A shows a normal nasopharynx in a brachycephalic dog. Figures 1B–1D show the nasopharynxes of brachycephalic dogs with nasopharyngeal turbinates protruding on each side of the vomer bone. In all figures, the image was obtained from retroflexion of an endoscope dorsally and cranially behind the soft palate. The vomer bone is seen dorsally; the soft palate is seen ventrally; and the nasopharynx is seen centrally. The nasopharyngeal turbinates that were encountered appeared either as a fused structure (Figures 1B, 1C) or separate, arising from either choanae (Figure 1D).Figures 1A–1D—. Figure 1A shows a normal nasopharynx in a brachycephalic dog. Figures 1B–1D show the nasopharynxes of brachycephalic dogs with nasopharyngeal turbinates protruding on each side of the vomer bone. In all figures, the image was obtained from retroflexion of an endoscope dorsally and cranially behind the soft palate. The vomer bone is seen dorsally; the soft palate is seen ventrally; and the nasopharynx is seen centrally. The nasopharyngeal turbinates that were encountered appeared either as a fused structure (Figures 1B, 1C) or separate, arising from either choanae (Figure 1D).
Figures 1A–1D—. Figure 1A shows a normal nasopharynx in a brachycephalic dog. Figures 1B–1D show the nasopharynxes of brachycephalic dogs with nasopharyngeal turbinates protruding on each side of the vomer bone. In all figures, the image was obtained from retroflexion of an endoscope dorsally and cranially behind the soft palate. The vomer bone is seen dorsally; the soft palate is seen ventrally; and the nasopharynx is seen centrally. The nasopharyngeal turbinates that were encountered appeared either as a fused structure (Figures 1B, 1C) or separate, arising from either choanae (Figure 1D).Figures 1A–1D—. Figure 1A shows a normal nasopharynx in a brachycephalic dog. Figures 1B–1D show the nasopharynxes of brachycephalic dogs with nasopharyngeal turbinates protruding on each side of the vomer bone. In all figures, the image was obtained from retroflexion of an endoscope dorsally and cranially behind the soft palate. The vomer bone is seen dorsally; the soft palate is seen ventrally; and the nasopharynx is seen centrally. The nasopharyngeal turbinates that were encountered appeared either as a fused structure (Figures 1B, 1C) or separate, arising from either choanae (Figure 1D).Figures 1A–1D—. Figure 1A shows a normal nasopharynx in a brachycephalic dog. Figures 1B–1D show the nasopharynxes of brachycephalic dogs with nasopharyngeal turbinates protruding on each side of the vomer bone. In all figures, the image was obtained from retroflexion of an endoscope dorsally and cranially behind the soft palate. The vomer bone is seen dorsally; the soft palate is seen ventrally; and the nasopharynx is seen centrally. The nasopharyngeal turbinates that were encountered appeared either as a fused structure (Figures 1B, 1C) or separate, arising from either choanae (Figure 1D).Figures 1A–1D—. Figure 1A shows a normal nasopharynx in a brachycephalic dog. Figures 1B–1D show the nasopharynxes of brachycephalic dogs with nasopharyngeal turbinates protruding on each side of the vomer bone. In all figures, the image was obtained from retroflexion of an endoscope dorsally and cranially behind the soft palate. The vomer bone is seen dorsally; the soft palate is seen ventrally; and the nasopharynx is seen centrally. The nasopharyngeal turbinates that were encountered appeared either as a fused structure (Figures 1B, 1C) or separate, arising from either choanae (Figure 1D).Figures 1A–1D—. Figure 1A shows a normal nasopharynx in a brachycephalic dog. Figures 1B–1D show the nasopharynxes of brachycephalic dogs with nasopharyngeal turbinates protruding on each side of the vomer bone. In all figures, the image was obtained from retroflexion of an endoscope dorsally and cranially behind the soft palate. The vomer bone is seen dorsally; the soft palate is seen ventrally; and the nasopharynx is seen centrally. The nasopharyngeal turbinates that were encountered appeared either as a fused structure (Figures 1B, 1C) or separate, arising from either choanae (Figure 1D).Figures 1A–1D—. Figure 1A shows a normal nasopharynx in a brachycephalic dog. Figures 1B–1D show the nasopharynxes of brachycephalic dogs with nasopharyngeal turbinates protruding on each side of the vomer bone. In all figures, the image was obtained from retroflexion of an endoscope dorsally and cranially behind the soft palate. The vomer bone is seen dorsally; the soft palate is seen ventrally; and the nasopharynx is seen centrally. The nasopharyngeal turbinates that were encountered appeared either as a fused structure (Figures 1B, 1C) or separate, arising from either choanae (Figure 1D).Figures 1A–1D—. Figure 1A shows a normal nasopharynx in a brachycephalic dog. Figures 1B–1D show the nasopharynxes of brachycephalic dogs with nasopharyngeal turbinates protruding on each side of the vomer bone. In all figures, the image was obtained from retroflexion of an endoscope dorsally and cranially behind the soft palate. The vomer bone is seen dorsally; the soft palate is seen ventrally; and the nasopharynx is seen centrally. The nasopharyngeal turbinates that were encountered appeared either as a fused structure (Figures 1B, 1C) or separate, arising from either choanae (Figure 1D).Figures 1A–1D—. Figure 1A shows a normal nasopharynx in a brachycephalic dog. Figures 1B–1D show the nasopharynxes of brachycephalic dogs with nasopharyngeal turbinates protruding on each side of the vomer bone. In all figures, the image was obtained from retroflexion of an endoscope dorsally and cranially behind the soft palate. The vomer bone is seen dorsally; the soft palate is seen ventrally; and the nasopharynx is seen centrally. The nasopharyngeal turbinates that were encountered appeared either as a fused structure (Figures 1B, 1C) or separate, arising from either choanae (Figure 1D).Figures 1A–1D—. Figure 1A shows a normal nasopharynx in a brachycephalic dog. Figures 1B–1D show the nasopharynxes of brachycephalic dogs with nasopharyngeal turbinates protruding on each side of the vomer bone. In all figures, the image was obtained from retroflexion of an endoscope dorsally and cranially behind the soft palate. The vomer bone is seen dorsally; the soft palate is seen ventrally; and the nasopharynx is seen centrally. The nasopharyngeal turbinates that were encountered appeared either as a fused structure (Figures 1B, 1C) or separate, arising from either choanae (Figure 1D).Figures 1A–1D—. Figure 1A shows a normal nasopharynx in a brachycephalic dog. Figures 1B–1D show the nasopharynxes of brachycephalic dogs with nasopharyngeal turbinates protruding on each side of the vomer bone. In all figures, the image was obtained from retroflexion of an endoscope dorsally and cranially behind the soft palate. The vomer bone is seen dorsally; the soft palate is seen ventrally; and the nasopharynx is seen centrally. The nasopharyngeal turbinates that were encountered appeared either as a fused structure (Figures 1B, 1C) or separate, arising from either choanae (Figure 1D).Figures 1A–1D—. Figure 1A shows a normal nasopharynx in a brachycephalic dog. Figures 1B–1D show the nasopharynxes of brachycephalic dogs with nasopharyngeal turbinates protruding on each side of the vomer bone. In all figures, the image was obtained from retroflexion of an endoscope dorsally and cranially behind the soft palate. The vomer bone is seen dorsally; the soft palate is seen ventrally; and the nasopharynx is seen centrally. The nasopharyngeal turbinates that were encountered appeared either as a fused structure (Figures 1B, 1C) or separate, arising from either choanae (Figure 1D).Figures 1A–1D—. Figure 1A shows a normal nasopharynx in a brachycephalic dog. Figures 1B–1D show the nasopharynxes of brachycephalic dogs with nasopharyngeal turbinates protruding on each side of the vomer bone. In all figures, the image was obtained from retroflexion of an endoscope dorsally and cranially behind the soft palate. The vomer bone is seen dorsally; the soft palate is seen ventrally; and the nasopharynx is seen centrally. The nasopharyngeal turbinates that were encountered appeared either as a fused structure (Figures 1B, 1C) or separate, arising from either choanae (Figure 1D).
Figures 1A–1D—. Figure 1A shows a normal nasopharynx in a brachycephalic dog. Figures 1B–1D show the nasopharynxes of brachycephalic dogs with nasopharyngeal turbinates protruding on each side of the vomer bone. In all figures, the image was obtained from retroflexion of an endoscope dorsally and cranially behind the soft palate. The vomer bone is seen dorsally; the soft palate is seen ventrally; and the nasopharynx is seen centrally. The nasopharyngeal turbinates that were encountered appeared either as a fused structure (Figures 1B, 1C) or separate, arising from either choanae (Figure 1D).Figures 1A–1D—. Figure 1A shows a normal nasopharynx in a brachycephalic dog. Figures 1B–1D show the nasopharynxes of brachycephalic dogs with nasopharyngeal turbinates protruding on each side of the vomer bone. In all figures, the image was obtained from retroflexion of an endoscope dorsally and cranially behind the soft palate. The vomer bone is seen dorsally; the soft palate is seen ventrally; and the nasopharynx is seen centrally. The nasopharyngeal turbinates that were encountered appeared either as a fused structure (Figures 1B, 1C) or separate, arising from either choanae (Figure 1D).Figures 1A–1D—. Figure 1A shows a normal nasopharynx in a brachycephalic dog. Figures 1B–1D show the nasopharynxes of brachycephalic dogs with nasopharyngeal turbinates protruding on each side of the vomer bone. In all figures, the image was obtained from retroflexion of an endoscope dorsally and cranially behind the soft palate. The vomer bone is seen dorsally; the soft palate is seen ventrally; and the nasopharynx is seen centrally. The nasopharyngeal turbinates that were encountered appeared either as a fused structure (Figures 1B, 1C) or separate, arising from either choanae (Figure 1D).Figures 1A–1D—. Figure 1A shows a normal nasopharynx in a brachycephalic dog. Figures 1B–1D show the nasopharynxes of brachycephalic dogs with nasopharyngeal turbinates protruding on each side of the vomer bone. In all figures, the image was obtained from retroflexion of an endoscope dorsally and cranially behind the soft palate. The vomer bone is seen dorsally; the soft palate is seen ventrally; and the nasopharynx is seen centrally. The nasopharyngeal turbinates that were encountered appeared either as a fused structure (Figures 1B, 1C) or separate, arising from either choanae (Figure 1D).Figures 1A–1D—. Figure 1A shows a normal nasopharynx in a brachycephalic dog. Figures 1B–1D show the nasopharynxes of brachycephalic dogs with nasopharyngeal turbinates protruding on each side of the vomer bone. In all figures, the image was obtained from retroflexion of an endoscope dorsally and cranially behind the soft palate. The vomer bone is seen dorsally; the soft palate is seen ventrally; and the nasopharynx is seen centrally. The nasopharyngeal turbinates that were encountered appeared either as a fused structure (Figures 1B, 1C) or separate, arising from either choanae (Figure 1D).Figures 1A–1D—. Figure 1A shows a normal nasopharynx in a brachycephalic dog. Figures 1B–1D show the nasopharynxes of brachycephalic dogs with nasopharyngeal turbinates protruding on each side of the vomer bone. In all figures, the image was obtained from retroflexion of an endoscope dorsally and cranially behind the soft palate. The vomer bone is seen dorsally; the soft palate is seen ventrally; and the nasopharynx is seen centrally. The nasopharyngeal turbinates that were encountered appeared either as a fused structure (Figures 1B, 1C) or separate, arising from either choanae (Figure 1D).Figures 1A–1D—. Figure 1A shows a normal nasopharynx in a brachycephalic dog. Figures 1B–1D show the nasopharynxes of brachycephalic dogs with nasopharyngeal turbinates protruding on each side of the vomer bone. In all figures, the image was obtained from retroflexion of an endoscope dorsally and cranially behind the soft palate. The vomer bone is seen dorsally; the soft palate is seen ventrally; and the nasopharynx is seen centrally. The nasopharyngeal turbinates that were encountered appeared either as a fused structure (Figures 1B, 1C) or separate, arising from either choanae (Figure 1D).Figures 1A–1D—. Figure 1A shows a normal nasopharynx in a brachycephalic dog. Figures 1B–1D show the nasopharynxes of brachycephalic dogs with nasopharyngeal turbinates protruding on each side of the vomer bone. In all figures, the image was obtained from retroflexion of an endoscope dorsally and cranially behind the soft palate. The vomer bone is seen dorsally; the soft palate is seen ventrally; and the nasopharynx is seen centrally. The nasopharyngeal turbinates that were encountered appeared either as a fused structure (Figures 1B, 1C) or separate, arising from either choanae (Figure 1D).Figures 1A–1D—. Figure 1A shows a normal nasopharynx in a brachycephalic dog. Figures 1B–1D show the nasopharynxes of brachycephalic dogs with nasopharyngeal turbinates protruding on each side of the vomer bone. In all figures, the image was obtained from retroflexion of an endoscope dorsally and cranially behind the soft palate. The vomer bone is seen dorsally; the soft palate is seen ventrally; and the nasopharynx is seen centrally. The nasopharyngeal turbinates that were encountered appeared either as a fused structure (Figures 1B, 1C) or separate, arising from either choanae (Figure 1D).Figures 1A–1D—. Figure 1A shows a normal nasopharynx in a brachycephalic dog. Figures 1B–1D show the nasopharynxes of brachycephalic dogs with nasopharyngeal turbinates protruding on each side of the vomer bone. In all figures, the image was obtained from retroflexion of an endoscope dorsally and cranially behind the soft palate. The vomer bone is seen dorsally; the soft palate is seen ventrally; and the nasopharynx is seen centrally. The nasopharyngeal turbinates that were encountered appeared either as a fused structure (Figures 1B, 1C) or separate, arising from either choanae (Figure 1D).Figures 1A–1D—. Figure 1A shows a normal nasopharynx in a brachycephalic dog. Figures 1B–1D show the nasopharynxes of brachycephalic dogs with nasopharyngeal turbinates protruding on each side of the vomer bone. In all figures, the image was obtained from retroflexion of an endoscope dorsally and cranially behind the soft palate. The vomer bone is seen dorsally; the soft palate is seen ventrally; and the nasopharynx is seen centrally. The nasopharyngeal turbinates that were encountered appeared either as a fused structure (Figures 1B, 1C) or separate, arising from either choanae (Figure 1D).Figures 1A–1D—. Figure 1A shows a normal nasopharynx in a brachycephalic dog. Figures 1B–1D show the nasopharynxes of brachycephalic dogs with nasopharyngeal turbinates protruding on each side of the vomer bone. In all figures, the image was obtained from retroflexion of an endoscope dorsally and cranially behind the soft palate. The vomer bone is seen dorsally; the soft palate is seen ventrally; and the nasopharynx is seen centrally. The nasopharyngeal turbinates that were encountered appeared either as a fused structure (Figures 1B, 1C) or separate, arising from either choanae (Figure 1D).
Figures 1A–1D — Figure 1A shows a normal nasopharynx in a brachycephalic dog. Figures 1B–1D show the nasopharynxes of brachycephalic dogs with nasopharyngeal turbinates protruding on each side of the vomer bone. In all figures, the image was obtained from retroflexion of an endoscope dorsally and cranially behind the soft palate. The vomer bone is seen dorsally; the soft palate is seen ventrally; and the nasopharynx is seen centrally. The nasopharyngeal turbinates that were encountered appeared either as a fused structure (Figures 1B, 1C) or separate, arising from either choanae (Figure 1D).

Citation: Journal of the American Animal Hospital Association 44, 5; 10.5326/0440243

Figures 2A, 2B—. The nasopharynxes of two brachycephalic cats are shown, with nasopharyngeal turbinates protruding on each side of the vomer bone. The images were obtained in the same manner as the images in Figures 1A–1D.Figures 2A, 2B—. The nasopharynxes of two brachycephalic cats are shown, with nasopharyngeal turbinates protruding on each side of the vomer bone. The images were obtained in the same manner as the images in Figures 1A–1D.Figures 2A, 2B—. The nasopharynxes of two brachycephalic cats are shown, with nasopharyngeal turbinates protruding on each side of the vomer bone. The images were obtained in the same manner as the images in Figures 1A–1D.Figures 2A, 2B—. The nasopharynxes of two brachycephalic cats are shown, with nasopharyngeal turbinates protruding on each side of the vomer bone. The images were obtained in the same manner as the images in Figures 1A–1D.Figures 2A, 2B—. The nasopharynxes of two brachycephalic cats are shown, with nasopharyngeal turbinates protruding on each side of the vomer bone. The images were obtained in the same manner as the images in Figures 1A–1D.Figures 2A, 2B—. The nasopharynxes of two brachycephalic cats are shown, with nasopharyngeal turbinates protruding on each side of the vomer bone. The images were obtained in the same manner as the images in Figures 1A–1D.
Figures 2A, 2B—. The nasopharynxes of two brachycephalic cats are shown, with nasopharyngeal turbinates protruding on each side of the vomer bone. The images were obtained in the same manner as the images in Figures 1A–1D.Figures 2A, 2B—. The nasopharynxes of two brachycephalic cats are shown, with nasopharyngeal turbinates protruding on each side of the vomer bone. The images were obtained in the same manner as the images in Figures 1A–1D.Figures 2A, 2B—. The nasopharynxes of two brachycephalic cats are shown, with nasopharyngeal turbinates protruding on each side of the vomer bone. The images were obtained in the same manner as the images in Figures 1A–1D.Figures 2A, 2B—. The nasopharynxes of two brachycephalic cats are shown, with nasopharyngeal turbinates protruding on each side of the vomer bone. The images were obtained in the same manner as the images in Figures 1A–1D.Figures 2A, 2B—. The nasopharynxes of two brachycephalic cats are shown, with nasopharyngeal turbinates protruding on each side of the vomer bone. The images were obtained in the same manner as the images in Figures 1A–1D.Figures 2A, 2B—. The nasopharynxes of two brachycephalic cats are shown, with nasopharyngeal turbinates protruding on each side of the vomer bone. The images were obtained in the same manner as the images in Figures 1A–1D.
Figures 2A, 2B — The nasopharynxes of two brachycephalic cats are shown, with nasopharyngeal turbinates protruding on each side of the vomer bone. The images were obtained in the same manner as the images in Figures 1A–1D.

Citation: Journal of the American Animal Hospital Association 44, 5; 10.5326/0440243

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Copyright: Copyright 2008 by The American Animal Hospital Association 2008
<bold> <italic toggle="yes">Figures 1A–1D</italic> </bold> —
Figures 1A–1D —

Figure 1A shows a normal nasopharynx in a brachycephalic dog. Figures 1B–1D show the nasopharynxes of brachycephalic dogs with nasopharyngeal turbinates protruding on each side of the vomer bone. In all figures, the image was obtained from retroflexion of an endoscope dorsally and cranially behind the soft palate. The vomer bone is seen dorsally; the soft palate is seen ventrally; and the nasopharynx is seen centrally. The nasopharyngeal turbinates that were encountered appeared either as a fused structure (Figures 1B, 1C) or separate, arising from either choanae (Figure 1D).

<bold> <italic toggle="yes">Figures 2A, 2B</italic> </bold> —
Figures 2A, 2B —

The nasopharynxes of two brachycephalic cats are shown, with nasopharyngeal turbinates protruding on each side of the vomer bone. The images were obtained in the same manner as the images in Figures 1A–1D.

Contributor Notes

Address all correspondence to Dr. McKiernan, Southern Oregon Veterinary Specialty Center, 3265 Biddle Road, Medford, Oregon 97504.
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