Association of magnetic resonance imaging findings and histologic diagnosis in dogs with nasal disease: 78 cases (2001-2004)

OBJECTIVE-To determine whether magnetic resonance imaging (MRI) features correlated with histologic diagnosis in dogs with nasal disease. DESIGN-Retrospective case series. ANIMALS-78 Dogs undergoing MRI for evaluation of nasal disease. PROCEDURES-Medical records and MRI reports of dogs were reviewed to identify MRI features associated with histologic diagnosis. Features evaluated were presence of a mass effect, frontal sinus involvement, sphenoid sinus involvement, maxillary recess involvement, nasopharyngeal infiltration by soft tissue, nasal turbinate destruction, vomer bone lysis, paranasal bone destruction, cribriform plate erosion, and lesion extent (ie, unilateral vs bilateral). RESULTS-33 Dogs had neoplastic disease, 38 had inflammatory rhinitis, and 7 had fungal rhinitis. Lesion extent was not significantly associated with histologic diagnosis. Absence of a mass effect was significantly associated with inflammatory disease. However, presence of a mass was not specific for neoplasia. In dogs with evidence of a mass on magnetic resonance (MR) images, nasal turbinate destruction, frontal sinus invasion, and maxillary recess invasion were not useful in distinguishing neoplastic from nonneoplastic disease, but cribriform plate erosion, vomer bone lysis, paranasal bone destruction, sphenoid sinus invasion, and nasopharyngeal invasion were. CONCLUSIONS AND CLINICAL RELEVANCE-Results suggested that in dogs with nasal disease, the lack of a mass effect on MR images was significantly associated with inflammatory disease. In dogs with a mass effect on MR images, vomer bone lysis, cribriform plate erosion, paranasal bone destruction, sphenoid sinus invasion by a mass, and nasopharyngeal invasion by a mass were significantly associated with a diagnosis of neoplasia.     

Intranasal hemangiosarcoma in a dog

Magnetic resonance (MR) was conducted for an 8-year-old, intact male Spitz with sneezing, serous discharge and epistaxis from the left nasal cavity. MR imaging showed a nasal cavity-occupied mass of iso-intensity on T1WI , high-intensity on T2WI and markedly enhanced on contrast-enhanced T1WI at parts of rostal to medial ocular angle in the left cavity. After Surgery and intraoperative radiation, the mass was diagnosed intranasal hemangiosarcoma by histopathology. Although the dog showed the finding, which suggested recurrence after the treatment ending, about 30 months later, it maintained good conditions without evidence of metastasis.     

COMBINATION OF COMPUTED TOMOGRAPHIC IMAGING CHARACTERISTICS OF MEDIAL RETROPHARYNGEAL LYMPH NODES AND NASAL PASSAGES AIDS DISCRIMINATION BETWEEN RHINITIS AND NEOPLASIA IN CATS

Feline nasal diseases are a diagnostic challenge. The objective of this retrospective, cross‐sectional study was to determine whether computed tomography (CT) imaging characteristics of the medial retropharyngeal lymph nodes (MRPLN), alone or in combination with CT imaging characteristics of the nasal passages, could aid in differentiation between rhinitis and nasal neoplasia. Cats were recruited from record archives at two veterinary facilities during the period of 2008–2012. Selection criteria were presentation for chronic nasal discharge, contrast‐enhanced CT of the head that included the MRPLN, and rhinoscopic nasal biopsy resulting in diagnosis of rhinitis or neoplasia. For each CT scan, two board‐certified veterinary radiologists recorded MRPLN size, attenuation, heterogeneity, contrast‐medium enhancement, margination, shape, presence of a lymph node hilus, perinodal fat, turbinate lysis, paranasal bone lysis, and nasal mass. Both readers were unaware of patient information at the time of CT interpretation. Thirty‐four cats with rhinitis and 22 cats with neoplasia were included. Computed tomographic characteristics significantly associated with neoplasia included abnormal MRPLN hilus (OR 5.1), paranasal bone lysis (OR 5.6), turbinate lysis (5.6), mass (OR 26.1), MRPLN height asymmetry (OR 4.5), and decreased MRPLN precontrast heterogeneity (OR 7.0). The combined features predictive of neoplasia were a nasal mass with abnormal hilus (OR 47.7); lysis of turbinates/paranasal bones with abnormal MRPLN hilus (OR 16.2). Findings supported the hypothesis that combining CT features of the nasal passages and MRPLN aided in differentiating rhinitis from neoplasia in cats.     

Computed tomography as an aid in the diagnosis of chronic nasal disease in dogs

OBJECTIVES: To assess the use of computed tomography (CT) in the diagnosis of chronic nasal disease in dogs. METHODS: A retrospective study of 85 dogs with chronic nasal discharge due to primary nasal disease, which had undergone nasal CT and biopsy, was carried out. Medical records were reviewed for signalment, clinical signs, CT findings, endoscopic findings and histopathology. The results obtained via CT were correlated with nasal histopathology and gross anatomical observations were recorded at the time of rhinoscopy. RESULTS: Neoplasia was diagnosed in 37 dogs for which CT typically revealed a soft tissue density associated with extensive turbinate destruction. Inflammatory rhinitis was diagnosed in 40 dogs. CT disclosed either normal turbinate structures or mild to moderate turbinate destruction, with or without the presence of soft tissue densities (mucopus) within the nasal passages. Fungal rhinitis was diagnosed in seven dogs for which CT disclosed extensive turbinate destruction with hyperlucency of the nasal passages. One dog had normal CT and histopathology findings. CLINICAL SIGNIFICANCE: CT greatly enhanced the ability to diagnose chronic nasal disease in dogs, providing detailed Information regarding the extent of the disease, accurate discrimination of neoplastic versus non-neoplastic diseases, and identification of areas of the nose to examine rhinoscopically and suspicious regions to target for biopsy.     

EFFECTS OF FLUID AND COMPUTED TOMOGRAPHIC TECHNICAL FACTORS ON CONSPICUITY OF CANINE AND FELINE NASAL TURBINATES

Turbinate destruction is an important diagnostic criterion in canine and feline nasal computed tomography (CT). However decreased turbinate visibility may also be caused by technical CT settings and nasal fluid. The purpose of this experimental, crossover study was to determine whether fluid reduces conspicuity of canine and feline nasal turbinates in CT and if so, whether CT settings can maximize conspicuity. Three canine and three feline cadaver heads were used. Nasal slabs were CT‐scanned before and after submerging them in a water bath; using sequential, helical, and ultrahigh resolution modes; with images in low, medium, and high frequency image reconstruction kernels; and with application of additional posterior fossa optimization and high contrast enhancing filters. Visible turbinate length was measured by a single observer using manual tracing. Nasal density heterogeneity was measured using the standard deviation (SD) of mean nasal density from a region of interest in each nasal cavity. Linear mixed‐effect models using the R package ‘nlme’, multivariable models and standard post hoc Tukey pair‐wise comparisons were performed to investigate the effect of several variables (nasal content, scanning mode, image reconstruction kernel, application of post reconstruction filters) on measured visible total turbinate length and SD of mean nasal density. All canine and feline water‐filled nasal slabs showed significantly decreased visibility of nasal turbinates (P < 0.001). High frequency kernels provided the best turbinate visibility and highest SD of aerated nasal slabs, whereas medium frequency kernels were optimal for water‐filled nasal slabs. Scanning mode and filter application had no effect on turbinate visibility.     

Usefulness of MRI compared with CT for diagnosis of mesenteric lymphoma in a dog

We evaluated the usefulness of MRI and compared it with CT for diagnosis of mesenteric lymphoma in a dog. The results in the plain CT, dynamic CT and plain MR (T1WI and T2WI) images suggested that the mass was a large single nodular lesion with abundant blood perfusion. On enhanced MRI(T1WI) , the mass was depicted as a tumor with adhesion to the gut wall. Exploratory laparotomy confirmed the mass was consistent with the findings on enhanced MRI. We think that MRI might be a useful imaging tool for diagnosis of canine mesenteric lymphoma.     

Radiographic, magnetic resonance imaging, computed tomographic, and rhinoscopic features of nasal aspergillosis in dogs

OBJECTIVE: To determine radiographic, magnetic resonance imaging (MRI), computed tomography (CT), and rhinoscopic features of nasal aspergillosis in dogs. DESIGN: Prospective study. ANIMALS: 15 client-owned dogs. PROCEDURE: All dogs had clinical signs of chronic nasal disease; the diagnosis of nasal aspergillosis was made on the basis of positive results for at least 2 diagnostic tests (serology, cytology, histology, or fungal culture) and detection of typical intrasinusal and intranasal fungal colonies and turbinate destruction via rhinoscopy. Radiography, MRI, and CT were performed under general anesthesia. Rhinoscopy was repeated to evaluate lesions and initiate treatment. Findings of radiography, MRI, CT, and rhinoscopy were compared. RESULTS: MRI and CT revealed lesions suggestive of nasal aspergillosis more frequently than did radiography. Computed tomography was the best technique for detection of cortical bone lesions; the nature of abnormal soft tissue, however, could not be identified. Magnetic resonance imaging allowed evaluation of lesions of the frontal bone and was especially useful for differentiating between a thickened mucosa and secretions or fungal colonies; however, fungal colonies could not be differentiated from secretions. Rhinoscopy allowed identification of the nature of intranasal and intrasinusal soft tissue but was not as useful as CT and MRI for defining the extent of lesions and provided no information regarding bone lesions. CONCLUSIONS AND CLINICAL RELEVANCE: The value of CT and MRI for diagnosis of nasal aspergillosis was similar and greater than that of radiography. Rhinoscopy is necessary because it is the only technique that allows direct visualization of fungal colonies.     

Effects of purified Pasteurella multocida dermonecrotoxin on the nasal ventral turbinates of fattening pigs: histological observations.

Fattening specific pathogen-free derived pigs were injected intramuscularly with dermonecrotoxin of Pasteurella multocida, capsular type D. Ten days later, the nasal ventral turbinates and liver were examined histologically. A moderate turbinate atrophy was observed due to an increased number of osteoclasts and the absence of intramembranous bone apposition. Liver lesions were limited to some hepatocyte necrosis, sinusoid neutrophil infiltration and Kupffer cell hypertrophy. This study demonstrated that adult pigs are sensitive to P. multocida dermonecrotoxin.     

COMPUTED TOMOGRAPHIC FINDINGS OF FUNGAL RHINITIS AND SINUSITIS IN CATS

The computed tomographic (CT) findings of fungal rhinitis/sinusitis in cats were characterized. The CT images of 10 cats ranging in age from 7 to 13 years were examined. The mean age was 10.8 years and all were neutered males. Nasal aspergillosis was diagnosed in five cats, cryptococcosis in three cats, hyalohyphomycosis in one cat, and trichosporonosis in one cat. Bilateral disease was present in eight cats, seven had abnormal soft tissue attenuation in two-thirds of the nasal cavity, and six had turbinate lysis. Seven cats had also lysis of the hard palate, nasal septum, or frontal bone. One cat had lysis of the cribriform plate. Five of the nine cats whose lymph nodes were imaged had lymph node enlargement. There was contrast medium enhancement in the nasal cavity in all cats, with either a primarily peripheral rim or heterogeneous pattern. There appears to be an overlap of clinical signs, age, and CT features of cats with nasal neoplasia and those with fungal rhinitis/sinusitis.     

Turbinate atrophy evaluation in pigs by computed tomography

Computed tomography (CT), a non-invasive visualisation technique was applied for imaging the bony structures of the nasal cavity of pigs, and compared to the traditional scoring system of turbinate atrophy in swine. Twenty-three 27-week-old pigs representing various stages of turbinate atrophy were used. Nasal structures were visually scored on CT scans and transversal cuts of the noses at the level of the first upper premolar teeth using the same scoring system in both cases. A tissue/air area ratio was also determined based on density differences. A highly significant correlation was found between visual scoring of CT images and transversal cuts of pig noses (r = 0.98, p < 0.0001) as well as between visual scoring of CT images and tissue/air area ratio determination (r = -0.82, p < 0.0001).     

CT findings in 20 dogs and six cats with confirmed nasal foreign bodies

The diagnosis and treatment of nasal foreign bodies usually includes a combination of rhinoscopy and imaging techniques, such as CT. The purpose of this retrospective, multicenter study was to describe the CT characteristics of nasal foreign bodies in dogs and cats and to determine if different nasal CT features exist between acute and chronic cases. Twenty dogs and six cats met the inclusion criteria. Eleven nasal foreign bodies (42%) were detected confidently with CT. The foreign body had a linear shape in 81% of cases and displayed a “tubular‐like appearance” in 54% of cases. In five cases (19%), a foreign body was suspected but not clearly visible. Additional CT changes were present in the nasal passages in 96% of the cases. The presence of turbinate destruction (P = .021) and mucosal thickening (P = .014) on CT were associated with the presence of a chronic nasal foreign body. In this sample, the nature of the foreign body did not influence its visibility and was not associated with specific CT characteristics. Computed tomography may be useful in the investigation of nasal foreign bodies, however, a negative CT examination does not exclude their presence.     

Relationship of porcine cytomegalovirus and B bronchiseptica to atrophic rhinitis in gnotobiotic piglets.

Both porcine cytomegalovirus (PCMV) and Bordetella bronchiseptica produced rhinitis and pneumonia when inoculated intranasally into young gnotobiotic pigs. With PCMV the nasal lesions were confirmed to the lamina propria, while Bordetella produced atrophy of the turbinate bones and hyperplasia and degeneration of the nasal epithelium. Some exacerbation of the lesions was observed in the nasal mucosa of pigs given both agents, but the degree of bone atrophy was not increased.     

The association between pneumonia and atrophic rhinitis in slaughter weight Swine

Four hundred and sixty-two pigs from 37 herds were examined at slaughter for the presence and extent of turbinate atrophy and pneumonia. Turbinate atrophy was scored by measuring the mm space between the turbinate bone and the floor of the nasal cavity on both sides of the nasal septum. The total percentage of pneumonic involvement for each lung was evaluated by scoring the percentage of each lobe that was consolidated.

There was a low, positive correlation between individual scores of turbinate atrophy and the associated percentage of lung involved with pneumonia (r = + 0.177; p < 0.001). There was a postive correlation between the herd mean turbinate atrophy score and the herd mean percentage pneumonia score (r = + 0.515; p = 0.001).

The age at slaughter was known for 95 pigs from four herds and was not significantly correlated with the mm of turbinate atrophy, or the percentage of pneumonia.

     

MAGNETIC RESONANCE IMAGING FEATURES OF SINONASAL DISORDERS IN HORSES

Diseases of paranasal sinuses and nasal passages in horses can be a diagnostic challenge because of the complex anatomy of the head and limitations of many diagnostic modalities. Our hypothesis was that magnetic resonance (MR) imaging would provide excellent anatomical detail and soft tissue resolution, and would be accurate in the diagnosis of diseases of the paranasal sinuses and nasal passages in horses. Fourteen horses were imaged. Inclusion criteria were lesions located to the sinuses or nasal passages that underwent MR imaging and subsequent surgical intervention and/or histopathologic examination. A low field, 0.3 tesla open magnet was used. Sequences in the standard protocol were fast spin echo T2 sagittal and transverse, spin echo T1 transverse, short‐tau inversion recovery (STIR) dorsal, gradient echo 3D T1 MPR dorsal (plain and contrast enhanced), spin echo T1 fatsat (contrast enhanced). Mean scan time to complete the examination was 53 min (range 39–99 min). Lesions identified were primary or secondary sinusitis (six horses), paranasal sinus cyst (four horses), progressive ethmoid hematoma (two horses), and neoplasia (two horses). The most useful sequences were fast spin echo T2 transverse and sagittal, STIR dorsal and FE3D MPR (survey and contrast enhanced). Fluid accumulation, mucosal thickening, presence of encapsulated contents, bone deformation, and thickening were common findings observed in MR imaging. In selected horses, magnetic resonance imaging is a useful tool in diagnosing lesions of the paranasal sinuses and nasal passages.     

COMPARISON OF RADIOGRAPHY AND COMPUTED TOMOGRAPHY FOR THE DIAGNOSIS OF CANINE NASAL ASPERGILLOSIS

To compare the radiographic and computed tomographic (CT) findings and to evaluate the sensitivity of radiography and CT for diagnosis of nasal aspergillosis in dogs, the radiographic and CT studies of 48 dogs with chronic nasal disease were reviewed separately. The radiographic and CT findings were recorded, and a diagnosis was made. The results obtained in the dogs with nasal aspergillosis (n = 25) were used. Based on definite aspergillosis as diagnosis, CT had a sensitivity of 88% and radiography of 72%. Considering definite and probable aspergillosis as equivalent, CT had a sensitivity of 92% and radiography of 84%. The sensitivity was higher in dogs with lesions affecting the entire nasal cavity and frontal sinus on at least one side (n = 20) with a sensitivity of 100% for CT and 90-95% for radiography than in dogs with lesions restricted to the nasal cavities (n = 5) where CT had a sensitivity of 60-80% and radiography of 0-40%. CT was superior to radiography for evaluation of the nasal cavities (mucosal thickening along the nasal bones, surrounding bone hyperostosis/lysis), frontal sinuses (mucosal thickening along the frontal bone, fluid/soft tissue, frontal bone hyperostosis/lysis), and differentiation between a cavitated-like or a mass-like process. This study suggests that CT is more sensitive than radiography for diagnosis of nasal aspergillosis in the dog because of a better demonstration of some changes suggestive of nasal aspergillosis. A diagnosis of a nasal aspergillosis restricted to the nasal cavities or associated with an FB is challenging, even with the use of CT.     

Growth kinetics of equine respiratory tract viruses in cell and organ cultures

Growth kinetics of equine influenza virus-A1, equine herpesvirus-1, and equine rhinovirus-1 were determined in susceptible cell monolayers and in organ cultures of equine fetal tracheal and nasal turbinate epithelium. Equine influenza virus-A1 was replicated in cell and organ cultures and was released more readily and for longer periods from nasal turbinate epithelium than from tracheal epithelium. Equine herpesvirus-1 was also replicated in cell and organ cultures. During the first 24 hours after inoculation, equine herpesvirus-1 was released more readily from tracheal epithelium than from nasal turbinate epithelium. Beyond postinoculation day 1, virus was released more readily and for longer periods from nasal turbinate epithelium than from tracheal epithelium. Equine rhinovirus-1 replicated in cell and organ cultures, but almost exclusively from nasal turbinate epithelium.     

GENDER,WEIGHT, AND AGE EFFECTS ON PREVALENCE OF CAUDAL ABERRANT NASAL TURBINATES IN CLINICALLY HEALTHY ENGLISH BULLDOGS: A COMPUTED TOMOGRAPHIC STUDY AND CLASSIFICATION

English Bulldogs have been reported to demonstrate abnormal growth and development of the nasal turbinates, which contribute to an increase in airway resistance and hence clinical signs of brachycephalic airway syndrome. The purpose of this prospective, cross‐sectional study was to assess the prevalence and severity of caudal aberrant turbinate protrusion via CT studies of English Bulldogs with, according to the owners, none or minimal clinical signs of brachycephalic airway syndrome. An additional objective was to propose a classification scheme for describing the degree of caudal aberrant turbinate protrusion in English Bulldogs and to apply this scheme in assessing the effect of gender, weight, and age on prevalence and severity of turbinate protrusion. The nasal cavities of 40 clinically healthy English Bulldogs were examined. The prevalence of caudal aberrant turbinates in this group was 100%. Using our proposed classification scheme, Grade 1 (minimal) was detected in 7 of 40 (17.5%), Grade 2 (mild) in 28 of 40 (70%), and Grade 3 (moderate) in 5 of 40 (12.5%) English Bulldogs. No significant effect of gender, weight, and age on degree of protrusion was found. In conclusion, this study identified minimal to moderate protrusion of caudal aberrant turbinates toward the nasopharynx in all the sampled English Bulldogs, despite the absence of clinical signs of brachycephalic airway syndrome.     

Radiographic signs in cats with nasal disease

Radiographic signs in 64 cats that had radiography as part of the diagnostic work-up for suspected nasal disease were reviewed in a blinded fashion. Final diagnoses in these cats were rhinitis in 27, primary nasal neoplasia in 21 and non-nasal disease in 16. The signs with highest predictive value for nasal neoplasia were displacement of midline structures (73%), unilateral generalised soft tissue opacity (70%), unilateral generalised loss of turbinate detail (69%) and evidence of bone invasion (64%). The only radiographic finding that occurred more frequently in cats with rhinitis was a nasal cavity within normal limits, and the predictive value of this sign was only 38%. Radiographic signs in cats with nasal neoplasia are similar to those reported in dogs, whereas the radiographic signs in cats with rhinitis are variable and non-specific, and may be absent.     

The radiological features of sixty cases of intra-nasal neoplasia in the dog

The radiographs of 60 cases of canine nasal neoplasia were reviewed. The dorso-ventral intra-oral view provided most information and the lateral view supplied supplementary detail. The most common changes were turbinate destruction rostrally and caudally, with a homogenous increase in radiopacity. Bilateral involvement was present in 38 cases. Absence (26) and thinning (7) of the vomer bone were found, as was deviation of the cartilaginous septum (11). Destruction of the maxilla or palatine bones produced radiolucencies which were superimposed on the increased radio-opacity in 17 cases.