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

Advantages of the co2 laser use in the rare condition of nasal mucosa squamous cell carcinoma surgery in dogs-a clinical prospective study

Nasal mucosa tumors are an uncommon process and very dificult to work on with surgery. Radiotherapy associated or not with chemotherapy is the standard method to treat the disease. However, its access it is in the majority of the case not possible, making the surgery the best choice to try to achieve the patient's control. The anatomy of the region makes the complete surgical resection very difficult to achieve using the common and conventional blade scalpel surgery. The study features the advantages of using a CO2 laser to perform nasal mucosa carcinoma surgery in 6 dogs (N = 6). For the work we used an Aesculigth CO2 surgical laser model -Vetscalpel®, with the settings of 12Watts in a Superpulse mode, and a 0.25-0.4 mm focus to dissect the nasal mucosa, and a 1.5 mm focus for vaporization of the area. All the masses were histopathologically characterized as squamous cells carcinoma. The CO2 surgical laser allow us to work in a bloodless region promoting a more accurate dissection of the nasal mucosa sparing therefore the underlying and adjacent tissues and being less invasive. Also, it was possible to do the vaporization of the entire surgical area interviened. None of the patients presented relapse of clinical signs. Only 2 individuals were alive at the end of the study, presenting a survival rate of 420 and 514 days, which is in the same line of literature results of the treatment with radiotherapy combined with chemotherapy wich shows a median of 474-580 days. The study demonstrates successful outcomes with CO2 laser surgery in treating nasal mucosa SCC in dogs, with patients experiencing improved survival rates compared to traditional treatment methods. This highlights the efficacy and potential of CO2 laser surgery as a valuable tool in managing aggressive nasal tumors in veterinary oncology.

Construction of diagnostic prediction model for canine nasal diseases using less invasive examinations without anesthesia

Advanced imaging techniques under general anesthesia are frequently employed to achieve a definitive diagnosis of canine nasal diseases. However, these examinations may not be performed immediately in all cases. This study aimed to construct prediction models for canine nasal diseases using less-invasive examinations such as clinical signs and radiography. Dogs diagnosed with nasal disease between 2010 and 2020 were retrospectively investigated to construct a prediction model (Group M; GM), and dogs diagnosed between 2020 and 2021 were prospectively investigated to validate the efficacy (Group V; GV). Prediction models were created using two methods: manual (Model 1) and LASSO logistic regression analysis (Model 2). In total, 103 and 86 dogs were included in GM and GV, respectively. In Model 1, the sensitivity and specificity of neoplasia (NP) and sino-nasal aspergillosis (SNA) were 0.88 and 0.81 in GM and 0.92 and 0.78 in GV, respectively. Those of non-infectious rhinitis (NIR) and rhinitis secondary to dental disease (DD) were 0.78 and 0.88 in GM and 0.64 and 0.80 in GV, respectively. In Model 2, the sensitivity and specificity of NP and SNA were 0.93 and 1 in GM and 0.93 and 0.75 in GV, respectively. Those of NIR and DD were 0.96 and 0.89 in GM and 0.80 and 0.79 in GV, respectively. This study suggest that it is possible to create a prediction model using less-invasive examinations. Utilizing these predictive models may lead to appropriate general anesthesia examinations and treatment referrals.

Imaging techniques in veterinary medicine. Part II: Computed tomography, magnetic resonance imaging, nuclear medicine

Radiography and ultrasonography are the most used techniques in veterinary clinical practice, due to organizational, managerial and, mostly, economic reasons. However, in the last decades, Computed tomography (CT), Magnetic Resonance Imaging (MRI) and, to a lesser extent, Nuclear Medicine (MN) are increasingly used. As we said in the previous article, all the Diagnostic Imaging techniques are actually "indispensable" in Veterinary Medicine, where many patients do not show any symptoms.This second part describes Computed Tomography (CT), Magnetic Resonance (MRI) and Nuclear Medicine techniques in Veterinary Medicine are described.

CT findings of nasal cryptococcosis in cats and dogs: A case series

Cryptococcus spp. can cause chronic rhinitis in cats and dogs. Computed tomography (CT) descriptions of imaging features of nasal cryptococcosis are limited. This retrospective single-center consecutive case series aimed to describe the CT features of lesions in cats and dogs with nasal cryptococcosis. Ten cats and 12 dogs with a diagnosis of nasal cryptococcosis confirmed with cytology, histopathology, and/or serology that had undergone a head CT from 2010 and 2020 were included. Images were evaluated by a veterinary radiologist for the presence of a nasal or nasopharyngeal mass, regional destruction, intracranial extension, and lymphadenopathy. The majority of cats (8/10 [80%]) had nasal lesions with most cases described as non-destructive rhinitis (7/8 [88%]). Three cats (3/10 [30%]) had a nasal mass. All cats had a nasopharyngeal mass, and in most cases (8/10 [80%]) the nasopharyngeal mass was centered caudally near the temporomandibular joints. None of the cats had cribriform plate lysis or meningeal enhancement. All dogs had nasal lesions. Eleven dogs (11/12 [92%]) had destructive rhinitis with lysis of nasal conchae. Most dogs (8/12; 67%) had a nasal mass, of which in seven dogs the caudal nasal mass extended into the rostral nasopharynx. Most dogs had cribriform plate lysis (9/12 [75%]), of which four dogs (44%) had mass extension into the cranium. Our findings support potential differences in CT features between dogs and cats with nasal cryptococcosis. Nasal cryptococcosis should be considered a differential diagnosis in dogs and cats with nasal and nasopharyngeal masses.

Nasal Rhinosporidiosis: Clinical Presentation, Clinical Findings, and Outcome in Dogs

The purpose of this study was to describe the clinical presentation, imaging findings, and outcome in 10 dogs diagnosed with Rhinosporidium seeberi infections. Histopathology and cytology records were searched at a veterinary teaching hospital and a veterinary diagnostic laboratory to identify dogs with rhinosporidiosis. Medical records were reviewed for clinical, imaging, endoscopic, and surgical findings. Outcome was determined via evaluation of records and, where possible, telephone conversation with the primary care veterinarian and/or owner. Young to middle-aged large-breed dogs with an approximately equal sex distribution were represented. Unilateral signs predominated. Diagnosis was confirmed by histopathology in 9 cases, and cytology was diagnostic in only 1 of 3 cases. Histopathology was superior to cytology. Masses were soft tissue and contrast enhancing with no evidence of bony lysis on computed tomography (2 dogs). Direct or rhinoscopic (2 dogs) visualization revealed white to yellow pinpoint foci. Surgical resection (4 dogs) can result in long-term disease-free periods (up to 2659 days), although repeat surgery can be required. Dapsone was well tolerated in 1 dog, and relapse was not noted despite incomplete surgical resection (follow-up 749 days). Visualization of pale foci on a rostral intranasal mass in an endemic region should prompt consideration of rhinosporidiosis.

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.

Anatomical description of the skulls of peccaries (Tayassu tajacu, Linnaeus 1758) by computed tomography

ABSTRACT The aim of this study was to evaluate the anatomical structures of the skulls of peccaries to establish the basis for their clinical study and future preclinical research. Ten skulls of adult peccaries were subjected to tomographic examination. The data obtained were processed via three-dimensional image reconstruction software (3D images). The reconstructions obtained from the neurocranium of the studied specimens allowed the identification and description of the following structures: nasal bone, frontal bone, parietal bones, incisor bone, maxillary bone, zygomatic bone, temporal bone, palatal bone, occipital bone, vomer bone, pterygoid bone, sphenoid bone, paranasal sinuses and orbit. Computed tomography proved to be an important diagnostic tool in the investigation of the skull of this species, allowing the acquisition of anatomical values not yet documented for the species in the literature.

Rhinoscopic Appearance and Clinical Features of a Nasal Transmissible Venereal Tumor in a Dog

A 2-year-old male neutered mixed breed dog was referred for evaluation of left-sided unilateral epistaxis and mucoid discharge following adoption from Mexico 2 months prior to presentation. Computed tomography (CT) showed soft tissue that filled the entirety of the left nasal passage with mild turbinate loss. Subsequent rhinoscopy revealed multifocal patches of discrete, white, wispy, vascularized abnormal tissue in the left nasal cavity. Cytology and histopathology procured with rhinoscopic-guidance were suspicious for transmissible venereal tumor (TVT). Confirmation of a TVT diagnosis was made with polymerase chain reaction for the long interspersed element inserted upstream of the c-myc gene. The dog was treated with 4 cycles of vincristine (0.5 mg/m², IV, once every 7 days) with complete and sustained resolution of clinical signs shortly after the third cycle. Nasal TVT in dogs is an uncommon presentation of a neoplasm that primarily results in genital or oral lesions. There is a void in the veterinary literature regarding the rhinoscopic appearance, as well as limited clinical descriptions of nasal TVT. Therefore, the objectives of this report were to provide a detailed description of the rhinoscopic appearance of a canine nasal TVT, in addition to clinical features, diagnostic findings, CT imaging, and successful therapeutic management.

Treatment of nasal tumours in dogs: a review

Nasal tumours are common neoplasms in dogs and often represent a diagnostic and therapeutic challenge due to their confined location within the nasal cavities. The main goal of this review is to extract the most relevant information from a wide and often confusing evidence-based medicine on the treatment of canine nasal tumours and conclude with current recommendations. This report highlights the different therapeutic modalities available and describes their technical aspects, interests and limitations. Megavoltage radiotherapy, as the most recent treatment and standard of care, is particularly examined, especially the different types of radiotherapy units, the main protocols used and their advantages and limits. Newer and non-conventional treatments are also discussed.

Upper digestive tract abnormalities in dogs with chronic idiopathic lymphoplasmacytic rhinitis

BACKGROUND

Chronic idiopathic lymphoplasmacytic rhinitis (CILPR) is a common inflammatory disorder of unknown etiology affecting the nasal cavity of dogs. The diagnosis is made by exclusion of other causes of nasal disease and specific therapeutic protocols are lacking. In human medicine, a relationship between CILPR and gastrointestinal clinical signs has been postulated, and remission of respiratory signs after clinical trials with medications for gastrointestinal disorders has been observed.

OBJECTIVES

To describe history, clinical presentation, endoscopic and histopathologic concurrent respiratory and digestive tract abnormalities, and to evaluate improvement of respiratory signs after treatment for gastrointestinal signs.

ANIMALS

Twenty-five dogs with CILPR.

METHODS

Prospective study. For inclusion, following information had to be available: respiratory and digestive clinical signs, airway and digestive tract endoscopic abnormalities, histologic evaluation of respiratory and gastrointestinal tract biopsy specimens, and clinical response to different treatment strategies.

RESULTS

Twenty-two dogs had endoscopic gastrointestinal lesions, whereas 13 dogs had concurrent gastrointestinal signs. Most esophageal and duodenal endoscopic abnormalities were classified as moderate or severe. Respiratory and gastrointestinal tract histologic evaluation identified mostly chronic inflammation. Remission or marked improvement of respiratory signs was observed in the majority of dogs treated only for gastrointestinal signs up to 12 months after endoscopy. No significant associations between treatments and follow-up information were found.

CONCLUSION AND CLINICAL IMPORTANCE

Nasal and upper digestive tract abnormalities coexist in some dogs with CILPR. Lack of standardized therapeutic protocols suggests caution when interpreting improvement in nasal clinical signs. Additional studies are needed to explore the possibility of a cause-effect relationship between the 2 processes.

Canine nasal septum deviation can be a normal variation and correlates with increasing skull indices

Nasal septal deviation has been studied in relation to nasal pathology and mass effect in dogs. The purpose of this retrospective, cross-sectional study was to compare the prevalence of nasal septal deviation in dogs with rhinitis, neoplasia, and those without nasal pathology based on the facial index, skull index, and cranial index. Computed tomographic studies of the nasal cavities of dogs performed over a 5-year period were retrospectively reviewed. This study had 233 dogs meeting the inclusion criteria with 135 dogs with no nasal pathology, 63 dogs with nasal neoplasia, and 35 dogs with rhinitis. The prevalence of nasal septal deviation, the angle, maximum distance, and longitudinal extent of deviation were recorded, as well as measurements to calculate the facial index, cranial index, and skull index. The results showed no difference in the prevalence of nasal septal deviation between dogs with nasal pathology and those without. The mean longitudinal extent of deviation and maximum distance of deviation was statistically greater for those with neoplasia compared to those with rhinitis and without nasal pathology. The longitudinal extent of deviation was inversely proportional to the cranial index, facial index, and skull index. The angle of deviation was directly proportional to the facial index and skull index. In conclusion, nasal septal deviation is an anatomic variant in different breeds of dogs with no predilection based on nasal pathology. Nasal septal deviation should be interpreted cautiously in the assessment of canine nasal disease.

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.

Canine Nasal Disease: An Update

Nasal disease in dogs is common and is often accompanied by chronic nasal discharge with or without other clinical signs. A thorough history and physical examination often guide the most appropriate choice of diagnostic testing to provide the best chance of attaining a diagnosis as to cause, and therefore, the most appropriate treatment. The purpose of this article is to guide the practitioner through a logical approach to the evaluation of dogs that are presented with signs of nasal disease.

Imaging in Non-neurologic Oncologic Treatment Planning of the Head and Neck

Imaging is critical for the diagnosis and staging of veterinary oncology patients. Although cytology or biopsy is generally required for diagnosis, imaging characteristics inform the likelihood of a cancer diagnosis, can result in a prioritized list of differentials that guide further staging tests, and assist in the planning of surgery, radiation, and chemotherapy options. Advanced imaging, such as CT and MRI, can better define the extent of disease for surgical and radiation planning for head and neck cancer cases in particular. Additionally, new imaging technologies are continually being translated into veterinary fields, and they may provide more options for cancer patients as they become more widely available.

Identification of probable telangiectatic osteosarcoma from a dog skull from multicultural settlement Polwica-Skrzypnik in Lower Silesia, Poland

This report presents canid cranial skeletal pathology from an excavation associated with the Przeworsk culture (III c. BC - V c. AD). The dog skull, an intentional inhumation, was dated to the Roman influence and the Migration period (I - V c. AD. The dog was a relatively large animal with a shoulder height calculated as approximately 60 cm. Massive bone changes localized on the facial surface of the left maxilla required a multistage diagnostic protocol. In addition to traditional macroscopic and morphometric evaluation, we used modern diagnostic imaging techniques such as digital radiography, computed tomography and 3D reconstruction. These, along with histopathological studies, allowed us to identify a primary malignant bone tumor: telangiectatic osteosarcoma.

The evaluation of three treatment protocols using oral prednisone and oral meloxicam for therapy of canine idiopathic lymphoplasmacytic rhinitis: a pilot study

Background

Idiopathic lymphoplasmacytic rhinitis (LPR) is a common inflammatory disorder of the nasal cavity in dogs due to unknown etiology. It is characterised by non-specific clinical signs, including nasal discharge, epistaxis and breathing problems. Diagnosis is usually based on the histopathologic identification of infiltrating plasmocytes and lymphocytes in the nasal mucosa and the exclusion of other underlying diseases. Treatment strategies include glucocorticoids, non-steroidal anti-inflammatory drugs, antibiotics and antifungal medications. The aim of this study was to evaluate the efficacy of various therapeutic protocols for managing canine lymphoplasmacytic rhinitis based on the results of clinical, endoscopic and histological examinations, and to determine the relapse rate for LPR in dogs.

Twenty dogs of different breeds and both sexes, aged 1 to 14 years, were divided into four groups, each consisting of five dogs, including three experimental groups diagnosed with LPR and a control group.

The dogs from the first experimental group were administered prednisone orally at 1 mg/kg/day in the first 4 weeks and 0,5 mg/kg/day in the following 2 weeks. The second group of dogs was administered meloxicam orally at 0,1 mg/kg/day in the first 3 weeks, followed by prednisone at 1 mg/kg/day in the following 2 weeks and 0,5 mg/kg/day in the last week of the treatment. The dogs from the third experimental group were administered meloxicam orally at 0,1 mg/kg/day for 6 weeks. The control group of dogs was administered empty gelatin capsules (placebo) orally for 6 weeks. Clinical signs, endoscopic and histopathologic lesions were scored before and after treatment. Groups were compared using Chi- squared statistics in a 2 × 2 table for pre- versus post-treatment scores.

Results

Clinical signs persisted in the group treated with meloxicam and were mostly resolved in prednisone-treated dogs. However, endoscopic and histological changes were still observed in these two groups after treatment. The severity of all diagnostic features was reduced in the group treated with meloxicam for 3 weeks followed by prednisone for 3 weeks. The significant differences (p < 0.05) were noted between experimental and control groups. The dogs showed a statistically significant reduction in characteristics of the LPR before and after treatment, as measured by clinical signs (Group 1vs.4 p = 0.00, group 2 vs 4 p = 0.00, group 3 vs 4 p = 0,01), by endoscopy (1 vs 4 p = 0,01, 2 vs 4 p = 0,00, 3 vs 4 p = 0,03), and by histopathology (groups 1 vs 4 p = 0,00, 2 vs 4 p = 0,00, 3 vs 4 p = 0,03). The significant differences were noted between experimental groups, as measured by endoscopy (group 2vs 3 p = 0,04), and by relapse rate (groups 1 and 2 p = 0,03, groups 2 and 3 p = 0,01).

Conclusions

The three treatment protocols administered to dogs improved clinical, endoscopic and histological status. However, oral administration of meloxicam for 3 weeks, followed by prednisone for 3 weeks, appeared to be the most successful treatment. These patients remained asymptomatic for 6 months.

Leiomyoma in the nasal cavity of a dog

A 7-year-old, 34-kg, neutered male Labrador retriever was presented with a 1-year history of intermittent sneezing with occasional left-sided epistaxis. CT revealed a mass in the left nasal cavity. Histopathological analysis of rhinoscopy-guided tissue biopsies was consistent with chronic necrotic and ulcerative rhinitis. Surgical debridement by ventral rhinotomy was subsequently performed and histopathological diagnosis was leiomyoma. Complete resolution of the nasal discharge and reduced sneezing frequency were observed after surgery. Fourteen months postoperatively, CT detected no regrowth of the mass.

Suspect Odontogenic Infection Etiology for Canine Lymphoplasmacytic Rhinitis

The role of odontogenic infection as an etiology for lymphoplasmacytic rhinitis in dogs was evaluated. An association between odontogenic infection and inflammatory rhinitis was identified in 55% of cases evaluated. Odontogenic infection was unlikely or undetermined in 10% and 35% of the cases, respectively. Cases of lymphoplasmacytic rhinitis had roentgen signs associated with endodontic disease, periodontal disease, or retained tooth roots in 60%, 45%, and 25% of the cases, respectively. A collaborative team based approach assessing inflammatory nasal disease is recommended. Based on the history and signalment of the individual patient, diagnostic modalities should be chosen wisely. In some cases, oral examination and intraoral radiographs may be a more direct and cost effective approach for diagnosis and treatment of inflammatory rhinitis.

Evaluation of the ventro 20° rostral-dorsocaudal oblique radiographic projection for the investigation of canine nasal disease

OBJECTIVE

To assess the ventro 20° rostral-dorsocaudal oblique projection for canine nasal disease as an alternative to the dorsoventral intra-oral view.

MATERIALS AND METHODS

Thirty-one dogs with nasal disease underwent radiography and computed tomography with a final diagnosis of underlying cause achieved through rhinoscopy, biopsy or cytology. Three independent observers, blinded to diagnosis, reviewed the nasal radiographs on two separate occasions. Intra- and inter-observer agreement and level of confidence on radiographic diagnosis were evaluated and radiographic diagnosis was compared with computed tomography and definitive diagnosis.

RESULTS

The ventro 20° rostral-dorsocaudal oblique projection of canine nasal cavities was feasible in anaesthetised dogs and gave diagnostic quality images in most dogs. Assessment of this view showed moderate to substantial agreement with computed tomography diagnosis but gave lower confidence in diagnosis. Interpretation of this radiographic projection had substantial to almost perfect repeatability but moderate reproducibility.

CLINICAL SIGNIFICANCE

The ventro 20° rostral-dorsocaudal oblique projection may be used as a valuable initial screening tool for canine nasal pathology in practices without access to advanced imaging, although computed tomography is still likely to provide greater diagnostic information.

Erosive rhinitis resembling granulomatosis with polyangiitis (Wegener's granulomatosis) in an Anatolian shepherd dog

Granulomatosis with polyangiitis (Wegener's granulomatosis) is one of the idiopathic immune-mediated small-vessel vasculitides described in humans which are characterised by the presence of circulating antineutrophil cytoplasmic antibodies. It most commonly involves capillaries, venules and arterioles of the ear, nose and throat, lungs and glomeruli. A case of destructive haemopurulent rhinitis associated with relapsing periods of pyrexia, lethargy and stiffness as well as generalised pulmonary infiltrates in a young Anatolian shepherd dog is presented that closely resembles granulomatosis with polyangiitis (GPA) as reported in humans. Perinuclear antineutrophil cytoplasmic antibodies (pANCA) were detected in the dog's serum. Signs resolved promptly and completely once immunosuppressive doses of prednisone were administered, and have not recurred. This is the first report on the use of pANCA to investigate rhinitis in dogs. It is also, to the authors’ knowledge, the first description of a relapsing haemopurulent lytic rhinitis in this species. The concurrent manifestations of erosive haemopurulent rhinitis, ground-glass opacities on pulmonary computed tomography, pyrexia and listlessness resemble GPA as described in humans.

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.

Neoplastic lesions in the nasal cavities of dogs

This paper aims at evaluating the frequency of nasal cavity tumors in dogs as well as comparing an endoscopic examination with a histopathological evaluation of the collected biopsy specimens. The study was conducted on 68 dogs. During the endoscopic examination, proliferative lesions were recognized in 20 dogs. During the histopathological examination, neoplastic lesions were confirmed in 95% of the dogs in which proliferative lesions were identified in the endoscopic examination. Adenocarcinoma occurred most frequently in the population under study.

Characteristics of canine nasal discharge related to intranasal diseases: a retrospective study of 105 cases

OBJECTIVES

To compare characteristics of nasal discharge caused by different intranasal aetiologies in dogs.

METHODS

Medical records of 105 dogs with nasal discharge due to intranasal disease were retrospectively reviewed with special focus on composition, severity, duration and localisation of discharge. On the basis of diagnostic findings, cases were classified into different disease groups and characteristics of discharge were compared between groups.

RESULTS

Cases were classified as having non-specific rhinitis (n=42), nasal neoplasia (n=23), foreign bodies (n=21), nasal mycosis (n=7) and miscellaneous disorders (n=13). Dogs with foreign bodies or nasal mycosis were significantly younger. Mucous components of discharge occurred more often in non-specific rhinitis and nasal neoplasia, although haemorrhagic components predominated in nasal neoplasia when discharge lasted ê14 days. Pure or mixed haemorrhagic discharge was significantly more common with nasal neoplasia, foreign bodies and nasal mycosis. Purulent components were associated with longer duration of discharge and predominantly seen in non-specific rhinitis and foreign bodies. Dogs with foreign bodies were presented earlier and sneezing was more frequent. Nasal stridor was significantly more often observed in dogs with nasal neoplasia.

CLINICAL SIGNIFICANCE

Characteristics of nasal discharge and associated clinical signs might aid in planning the diagnostic approach, but a combination of diagnostic techniques is still required to confirm a diagnosis.

Canine nasal disease

Nasal disease often manifests as nasal discharge with or without other nasal signs. Attention to signalment, history, and physical examination findings often facilitates a differential diagnosis. Imaging techniques and tissue sampling for microscopic examination are usually necessary for diagnosis. Advanced imaging offers important advantages over traditional skull radiographs but is less widely available and more costly. Bacterial culture is seldom beneficial, and fungal culture is reserved for cases likely to have fungal rhinitis. Nasal biopsy is required to confirm a specific diagnosis and is always required for diagnosis of specific tumor type or for inflammatory rhinitis.

Cryptococcosis as an emerging systemic mycosis in dogs

OBJECTIVE

To review the etiology, pathogenesis, and clinical presentations of canine cryptococcosis that are of relevance to veterinary emergency and critical care veterinarians. Diagnosis, treatment, and public health considerations of the disease will also be discussed.

ETIOLOGY

Cryptococcosis is a multisystemic disease of dogs, with a predilection for the CNS, caused by encapsulated yeast species of the genus Cryptococcus. The 2 main pathogenic species are Cryptococcus neoformans and Cryptococcus gattii (previously known as C. neoformans var. gattii). Cryptococcosis is an emerging disease in North America, with C. gattii gaining prominence as a cause of serious veterinary and human disease.

DIAGNOSIS

Definitive diagnosis is made by serologic (antigen) testing, culture, and identification of the organism using light microscopy. False negatives and false positives, while uncommon, can occur in dogs using commercially available antigen tests. Cytological examination demonstrates the organism in a majority of cases, although culture is more sensitive. Specific media are required to differentiate between C. neoformans and C. gattii.

THERAPY

The most commonly used antifungal drugs to treat canine cryptococcosis are azole antifungals and amphotericin B. Some strains of Cryptococcus are resistant to antifungal drugs, especially fluconazole. Cautious use of glucocorticoids in critically affected dogs with CNS presentations can improve outcome.

PROGNOSIS

Prognosis is variable and depends on the severity of disease, underlying host immunocompetence, and financial constraints of the owner. Altered mental status in dogs with CNS cryptococcosis is a negative prognostic indicator.

Transitional carcinoma with extensive invasion of the bony orbit in a dog

A 12-year-old male English Pointer was examined due to a soft-tissue swelling at the medial canthus of the right orbital region, which was causing facial deformity. The dog had epiphora, purulent nasal discharge, epistaxis, dyspnea, and progressive weight loss. An intraoral mass was observed near the right maxillary premolars. Neoplastic disease was diagnosed based on ancillary tests, which included blood work, skull and intraoral radiographs, ocular ultrasonography and computed tomography. Histopathology revealed transitional carcinoma involving the nasal and oral cavities, maxilla, bony orbit and retrobulbar space. Nasal tumors represent approximately 2% of all tumors diagnosed in this species. Transitional carcinoma is the second most common type of malignant epithelial tumor in the nasal sinuses. This case illustrates the extensive destruction of the soft and bony tissues of the face, including the bony orbit that this type of tumor can cause.

Late presentation of canine nasal tumours in a UK referral hospital and treatment outcomes

OBJECTIVES

To determine the computed tomographic stage of dogs with nasal tumours in a UK referral population, and whether stage, time to referral and treatment correlates with outcome.

METHODS

Retrospective review of clinical records and computed tomography scans of dogs with nasal tumours.

RESULTS

Dogs (n=78) presented to a referral practice in the UK with suspected nasal tumours are presented with more late stage tumours than dogs in the USA and Japan. Length of time from initial presentation to referral did not correlate with tumour stage at diagnosis. Median survival times for radiotherapy-treated dogs in this population are equivalent to those previously reported for late stage nasal tumours.

CLINICAL SIGNIFICANCE

Dogs with nasal tumours are presented late in the course of disease in the North West of England. Dogs with clinical signs consistent with a nasal tumour should have timely imaging and biopsy, in order to make prompt treatment decisions. Although survival times are comparable with previous reports and radiotherapy is a valid treatment option for dogs with late stage disease, better outcomes are likely to be achievable with earlier treatment.

Unique topographic distribution of greyhound nonsuppurative meningoencephalitis

Greyhound nonsuppurative meningoencephalitis is an idiopathic breed-associated fatal meningoencephalitis with lesions usually occurring within the rostral cerebrum. This disorder can only be confirmed by postmortem examination, with a diagnosis based upon the unique topography of inflammatory lesions. Our purpose was to describe the magnetic resonance (MR) imaging features of this disease. Four Greyhounds with confirmed Greyhound nonsuppurative meningoencephalitis were evaluated by MR imaging. Lesions predominantly affected the olfactory lobes and bulbs, frontal, and frontotemporal cortical gray matter, and caudate nuclei bilaterally. Fluid attenuation inversion recovery (FLAIR) and T2 weighted spin-echo (T2W) sequences were most useful to assess the nature, severity, extension, and topographic pattern of lesions. Lesions were predominantly T2-hyperintense and T1-isointense with minimal or absent contrast enhancement.

Clinical experience of using multidetector-row CT for the diagnosis of disorders in cattle

To determine the clinical usefulness of multidetector-row CT for the diagnosis of disorders in cattle, images were obtained from 27 cattle, which were then subjected to postmortem and histopathological examinations. The cattle were divided into three categories of disorder: neurological (18 cases), skeletal (four cases) and other (five cases). In five cattle, which were suspected to have brain diseases, no abnormalities were identified by either CT or histopathological examination. Eight types of lesions were detected by CT in the cattle with neurological and vestibular disorders. The diseases diagnosed included hydrocephalus (three cases), intracranial arachnoid cysts (three cases), otitis media (five cases), cerebral abscess (one case), meningoencephalocele (one case), porencephaly (one case), bicephalus (one case) and rupture of the spinal cord (one case). Lesions were identified in all the cattle with skeletal disorders, including luxation (two cases), fracture (two cases), spondylosis (one case) and congenital disorders of the skeletal system (one case). Morphological disorders in the eyes (one case), nasal cavity (two cases), frontal sinuses (one case), thyroid glands (two cases), lung fields (two cases) and abdominal organs (two cases) were diagnosed by CT.

Intranasal infusion of clotrimazole for the treatment of nasal aspergillosis in two cats

CASE DESCRIPTION

2 cats (13 and 11 years old) were evaluated to determine the cause of nasal discharge of varying duration (4 days and 5 months, respectively).

CLINICAL FINDINGS

Computed tomography revealed marked turbinate destruction and soft tissue densities in the nasal passages. Histologic examination of nasal specimens revealed chronic active inflammation and branching fungal hyphae consistent with Aspergillus spp. Fungal culture of nasal specimens resulted in growth of Aspergillus spp. Testing yielded negative results for antibodies against Aspergillus spp.

TREATMENT AND OUTCOME

Both cats were anesthetized and treated with a 1-hour intranasal infusion of clotrimazole. Recovery from the procedure was uncomplicated, and both cats had complete resolution of clinical signs.

CLINICAL RELEVANCE

Little information is available on the treatment of nasal aspergillosis in cats, and the prognosis for affected animals is considered poor. The procedure for local intranasal infusion of clotrimazole in 2 cats was described here. Results and follow-up monitoring for both cats suggested that this may be a safe, effective, and durable treatment for cats with nasal aspergillosis.

Comparison of computed tomography and magnetic resonance imaging for the evaluation of canine intranasal neoplasia

OBJECTIVES

Canine intranasal neoplasia is commonly evaluated using computed tomography to indicate the diagnosis, to determine disease extent, to guide histological sampling location and to plan treatment. With the expanding use of magnetic resonance imaging in veterinary medicine, this modality has been recently applied for the same purpose. The aim of this study was to compare the features of canine intranasal neoplasia using computed tomography and magnetic resonance imaging.

METHODS

Twenty-one dogs with confirmed intranasal neoplasia underwent both computed tomography and magnetic resonance imaging. The images were reviewed retrospectively for the bony and soft tissue features of intranasal neoplasia.

RESULTS

Overall computed tomography and magnetic resonance imaging performed very similarly. However, lysis of bones bordering the nasal cavity and mucosal thickening was found on computed tomography images more often than on magnetic resonance images. Small amounts of fluid in the nasal cavity were more often seen on magnetic resonance images. However, fluid in the frontal sinuses was seen equally well with both modalities.

CLINICAL SIGNIFICANCE

We conclude that computed tomography is satisfactory for evaluation of canine intranasal neoplasia, and no clinically relevant benefit is gained using magnetic resonance imaging for intranasal neoplasia without extent into the cranial cavity.

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.

Prevalence, clinical features, and causes of epistaxis in dogs: 176 cases (1996-2001)

OBJECTIVE

To determine prevalence, clinical features, and causes of epistaxis in dogs.

DESIGN

Retrospective case series.

ANIMALS

176 dogs with epistaxis.

PROCEDURES

Medical records were reviewed for information related to signalment, clinical features, diagnosis, and outcome.

RESULTS

132 (75%) dogs were initially examined by the hospital's emergency service; prevalence of epistaxis was 0.3%. Dogs with epistaxis were more likely to be old (> or = 6 years), male, and large (> or = 26 kg [58.5 lb]) than were dogs in a reference population. In 109 (62%) dogs with epistaxis, an underlying cause was identified; 115 underlying disorders were identified, with 90 classified as local and 25 classified as systemic. Local causes of epistaxis included nasal neoplasia (n = 35), trauma (33), idiopathic rhinitis (20), and periapical abscess (2). Systemic causes included thrombocytopenia (12), thrombocytopathia (7), coagulopathy (3), hypertension (2), and vasculitis (1). Dogs with local causes were more likely to have unilateral than bilateral epistaxis, but 11 of 21 (52%) dogs with systemic disorders also had unilateral epistaxis. Dogs with systemic disorders were more likely to have clinical signs of systemic disease. Duration of epistaxis (acute vs chronic), severity, and duration of hospitalization were similar for dogs with local versus systemic disorders.

CONCLUSIONS AND CLINICAL RELEVANCE

Results suggested that epistaxis was a common disorder in dogs and frequently regarded as an emergency. Local causes of epistaxis were predominant, but clinical features traditionally thought to be helpful in distinguishing local versus systemic causes could not be reliably used for this purpose.

Advanced imaging for veterinary cancer patients

This article presents an update on the recent advances made in veterinary advanced imaging specifically with regard to cross-sectional modalities (CT and MRI) and nuclear medicine (positron emission tomography [PET] and PET/CT). A brief summary of technical improvements and a review of recent literature are included to provide an overview of the progress made in this important element of the practicing veterinary oncologist's repertoire. An in-depth summary of PET is also included to introduce the technical aspects and potential clinical and research applications of this novel imaging modality in veterinary medicine.

Computed tomography in small animals – Basic principles and state of the art applications

Since its clinical introduction, computed tomography (CT) has revolutionized veterinary medicine and is considered to be one of the most valuable tools for the imaging work-up of neurological, oncological and orthopaedic canine and feline patients. In small animals with acute trauma, particularly those involving complex anatomic areas such as the head, spine or pelvis, CT has been established as a standard imaging method. With the increasing availability of radiation therapy in veterinary medicine, CT has also become the principal tool to stage a tumour, assess response, and guide radiation therapy. The increasing availability of helical CT in veterinary medicine has allowed novel techniques such as spiral CT angiography and high-resolution CT. This review provides a brief overview of the historical and technical development of CT and literature reviews of the major clinical CT applications in small animals such as intracranial and extracranial lesions, the spine, the appendicular skeleton, and abdominal and thoracic diseases.

Nasal computed tomography

Chronic nasal disease is often a challenge to diagnose. Computed tomography greatly enhances the ability to diagnose chronic nasal disease in dogs and cats. Nasal computed tomography provides detailed information regarding the extent of disease, accurate discrimination of neoplastic versus nonneoplastic diseases, and identification of areas of the nose to examine rhinoscopically and suspicious regions to target for biopsy.

Canine chronic inflammatory rhinitis

Chronic inflammatory rhinitis is commonly found in dogs with chronic nasal disease and is characterized by lymphoplasmacytic infiltrates in the nasal mucosa in the absence of an obvious etiologic process. The pathogenesis of lymphoplasmacytic rhinitis remains unknown. Animals respond poorly to antibiotics, oral glucocorticoids, and antihistamines, making primary infectious, immune-mediated, or allergic etiologies unlikely. Aberrant immune response to inhaled organisms or allergens may induce inflammation in some animals. Common clinical signs include nasal discharge, sneezing, coughing, epistaxis, and stertor. Diagnosis is made by performing a thorough history, physical examination, radiography or advanced imaging (via computed tomography or magnetic resonance imaging), rhinoscopy, and nasal mucosal biopsy to rule out primary etiologies of nasal discharge. Treatment strategies have included various antibiotics, antihistamines, oral and inhalant steroids, nonsteroidal antiinflammatories, and antifungal medications. Some dogs may respond partially to doxycycline or azithromycin, although it is unclear whether response is related to antimicrobial or antiinflammatory properties of these drugs. Hydration of the nasal cavity through nasal drops or aerosols may limit nasal discharge, and some animals may improve with inhalant (but rarely oral) glucocorticoids.