Computed tomographic imaging of a maxillary sinus mucocele in an 8-year-old French Bulldog.

An 8-year-old male neutered French Bulldog was referred for continued nasal dyspnea following a staphylectomy revision performed one month prior to presentation. The patient had a prior history of skin allergies and underwent brachycephalic airway surgery performed at one year of age. Computed tomography (CT) revealed an osseous-encased, cystic mass arising from the right maxillary sinus. Surgical biopsies were performed and a mucocele with sinusitis and glandular hyperplasia was diagnosed. Based on our systematic review of the literature, maxillary sinus mucocele has not been reported in the dog and should be among the differentials for sinus cystic masses.

Radiographic and CT features of zygomatic arch pneumatization in a Thoroughbred with a recurrent progressive ethmoid hematoma.

A 7-year-old Thoroughbred gelding presented with a history of mild unilateral right-sided epistaxis and facial swelling over the right caudal maxillary sinus and zygomatic arch. Eleven months previously a progressive ethmoid hematoma had been surgically removed from the right caudal maxillary and conchofrontal sinus. Computed tomography identified a large expansile soft-tissue attenuating mass in the right caudal maxillary sinus, with protrusion into the conchofrontal sinus, that extended into the zygomatic arch. Lytic expansion and thinning of the cortex with pneumatization of the zygomatic arch was present. The mass was surgically excised after a biopsy had confirmed the recurring progressive ethmoid hematoma.

Outcomes following single, caudally based bilateral versus unilateral frontonasal sinusotomy for treatment of equine paranasal sinus disease.

BACKGROUND: Bilateral sinus disease is relatively uncommon in horses, accounting for 3%-4.5% of horses with sinonasal disease, but may require bilateral paranasal surgery for complete resolution. Complications and recurrence following bilateral sinusotomy have not been reported or compared to those following unilateral procedures. OBJECTIVE: To describe clinical features and outcomes in horses undergoing standing single, caudally based bilateral frontonasal sinusotomy compared to unilateral frontonasal surgery. METHODS: Records of horses (n = 37) undergoing surgical treatment for sinus disease (five bilateral, 32 unilateral) were retrospectively reviewed (2010-2017) for signalment, presenting complaint, duration of signs preoperatively, diagnostic imaging, treatments administered, duration hospitalization, complications, and owner satisfaction with the procedure. Mann-Whitney testing was used to compare age, duration of hospitalization, and follow-up time in horses undergoing unilateral or bilateral procedures. Fisher's exact testing was used to determine if sex predilection was present for unilateral or bilateral disease. Survival time and time to recurrence were compared by Kaplan-Meier survival curves and log-rank curve comparison testing. Significance was assessed at p < 0.05. RESULTS: Length of signs prior to admission did not differ between horses with unilateral and bilateral disease (p = 0.09), but there was a tendency for horses with bilateral disease to have clinical signs for longer. Age (p = 0.19) and hospitalization duration (p = 0.53) did not differ between horses undergoing unilateral versus bilateral procedures. Recurrence or failure to resolve signs was reported in 11/32 (34%) of unilateral and 0/5 bilateral cases (p = 0.07). CONCLUSIONS: The bilateral single, caudally based sinusotomy approach may be considered to effectively treat bilateral paranasal sinus disease without concern for increased risk of life-threatening complications or longer hospitalization duration than would be typical for unilateral sinusotomy procedures.

Equine Sinus Surgery.

The anatomy of the equine paranasal sinuses is critical to understand to assess the extent of the disease process, the optimal surgical approach, and the ability to drain through the normal nasomaxillary pathway. By following established anatomic landmarks, direct sinus access can be used to further explore the sinus compartments, remove compromised cheek teeth, remove any purulent debris or feed contamination, and establish drainage. Many complications can be avoided or minimized by thoroughly evaluating all sinus compartments and critically assessing the ability of the sinus to drain.

Computed tomography characteristics of equine paranasal sinus cysts.

BACKGROUND: Computed tomography (CT) is commonly used to investigate equine paranasal sinus disease, however, only limited information is available in the literature about the detailed CT appearance of equine paranasal sinus cysts. OBJECTIVES: To investigate if paranasal sinus cysts have specific characteristics in CT images that allow differentiation from other sinus diseases. STUDY DESIGN: Retrospective observational study. METHODS: Evaluation and comparison of CT studies of eight horses with surgically and/or histopathologically confirmed paranasal sinus cysts and 10 horses with other confirmed paranasal sinus diseases. RESULTS: A discrete hyperattenuating wall-like structure was detected in the periphery of the sinus lesion in precontrast acquisition in 7/8 horses with paranasal sinus cysts. A similar wall-like structure was detected in 3/10 horses with other sinus diseases, however, in contrast to horses with paranasal sinus cysts, two of these also had hyperattenuating regions within the contents of the sinus lesion. Bone destruction and formation affecting cancellous and cortical bone and dental disease were frequent in horses with paranasal sinus cysts. No significant difference in attenuation values was found when the fluid/soft tissue attenuation contents of lesions in horses with paranasal sinus cysts (mean 28.9 ± SD 9.2 HU) were compared with other sinus diseases when ethmoid haematomas were excluded (30.4 ± 12.9 HU, P = .8). MAIN LIMITATIONS: Low number of cases. CONCLUSIONS: Detection of a hyperattenuating cystic wall is a helpful feature for identifying paranasal sinus cysts in CT images of horses. In contrast, measurement of attenuation values of the soft tissue/fluid contents of the sinus lesions was not helpful in identifying paranasal sinus cysts.

Identification of the environmental source of infection for a domestic ferret with cryptococcosis.

Cryptococcosis, caused by the Cryptococcus gattii and C. neoformans species complexes, is an environmentally acquired mycosis affecting a broad range of host species. Among 9 communally housed ferrets, a 5-y-old castrated male ferret domiciled in an outdoor enclosure in Sydney, Australia was diagnosed with sinonasal cryptococcosis. Clinical signs resolved during 18 mo of itraconazole therapy, but the ferret was eventually euthanized because of splenic hemangiosarcoma. At postmortem, microscopic foci of persistent cryptococcosis were detected. The diagnosis raised concerns that the owners and other ferrets were exposed to a common environmental source of infection, thus prompting an investigation. Soil samples, swabs of a hollow eucalypt log (used for behavioral enrichment), and nasal swabs from 8 asymptomatic ferrets were collected. Nasal exudate (obtained at diagnosis) and tissues (collected at postmortem) were available from the clinical case. Bird seed agar culture resulted in a heavy growth of Cryptococcus spp. from one environmental site (the log), one nasal swab, and nasal exudate and tissues from the clinical case. All other samples were culture-negative. Sub-cultured isolates from the log were a mixture of C. gattii molecular type VGI and C. neoformans molecular type VNI. Ferret isolates were a similar mixture of C. gattii VGI (all disease isolates) and C. neoformans VNI (nasal-colonizing isolate). Multilocus sequence typing further revealed the ferret isolates as identical to environmental isolates collected from the log, confirming the log as the source of clinical disease and nasal colonization. The log was removed to prevent further exposure to a high environmental load of Cryptococcus spp.

A bilateral sinus cyst treated via a bilateral frontonasal bone flap in a standing horse.

Bilateral paranasal sinus diseases are rarely reported in horses. Treatment using a bilateral frontonasal bone flap on a standing, regular-sized adult horse has not been described previously. A 13-year-old Thoroughbred gelding was evaluated for bilateral mucopurulent nasal discharge. Radiographic, endoscopic and computed tomographic examinations revealed bilateral sinus pathological changes consistent with an ethmoid haematoma involving the maxillary and frontal sinuses. A bilateral frontonasal bone flap was created under standing sedation and local anaesthesia. A tracheotomy was performed initially to ensure a patent airway during the procedure. Additional analgesia had to be given to transect the dorsal part of the nasal septum while elevating the flap. The sinus masses were removed and communications with the nasal cavities created uneventfully. Small sequestra were removed transendoscopically from the left caudal maxillary sinus 4 weeks after the initial procedure. The horse made a complete recovery with an excellent cosmetic outcome. Histopathology revealed the mass to be a sinus cyst. We concluded that a bilateral sinus bone flap can be used in adult regular-sized horses to access the left and right paranasal sinuses simultaneously. Regional nerve blocks should be performed in order to increase analgesia. A temporary tracheotomy prevents any airway obstruction during the procedure. The post-operative cosmesis is excellent.

Paranasal sinus cysts in the horse: Complications related to their presence and surgical treatment in 37 cases.

BACKGROUND: Paranasal sinus cysts (PSC) are a common cause of equine secondary sinusitis. The outcome and associated complications have not been frequently reported. OBJECTIVES: To review the associated clinical signs, associated morbidities and outcomes of horses treated for PSC. STUDY DESIGN: Retrospective multicentre case series. METHODS: Retrospective analysis of case records and telephone follow up survey. RESULTS: Subjects were 37 horses 1-24 years old that were presented with nasal discharge (n = 31), facial swelling (n = 25) and epiphora (n = 19). Radiography and computed tomography allowed identification of the cyst-induced changes including concomitant tissue destruction (n = 31), leading among other things to local nerve damage causing headshaking (n = 6) and unilateral blindness (n = 1). Radiographic changes to adjacent dental apices were present in 10 horses. Horses over 10 years old showed more of the named associated problems. Post-operative complications included surgical site infection (SSI) (n = 11), nasofrontal suture periostitis (n = 6) and sequestration (n = 1) following removal of the PSC via osteotomy. The long-term response to treatment was available for 28 cases with 22 horses (78.6%) fully cured, 4 (14.3%) partially cured and 2 (7.1%) not responding to treatment. In 7 horses (18.9%) there was recurrence of the cyst post-operatively. MAIN LIMITATIONS: Due to the study being a multicentre retrospective case series with collection of data over an extended period, there may be inconsistency in data recording and absence of reporting of some findings. CONCLUSIONS: Overall, the diagnosis and treatment of sinus cysts is relatively straightforward and carries a good prognosis. In long-standing cases complications secondary to the expansive growth of cysts will dramatically affect the prognosis for full recovery due to pressure-induced changes to facial bones, cheek teeth and nerves. These secondary complications mainly occurring in older horses may be due to a combination of a relatively longer period of affection and the inflexibility of older horses' bones. Cyst recurrence following treatment can occur in up to 19% of cases.

Surgery of the Sinuses and Eyes.

Conditions of the head requiring surgery in cattle are not uncommon when considering the incidence of conditions such as ocular squamous cell carcinoma and requests for surgical dehorning. Surgery involving the eyes in cattle is relatively common, whereas surgery of the paranasal sinuses is less common. Generally speaking, however, surgery for conditions of the head tend to have a more favorable prognosis when there is early intervention.

Perineural Injection of the Ethmoidal Nerve of Horses.

OBJECTIVE: To describe the anatomical location of the ethmoidal nerve in the equine periorbital region and to determine the accuracy of a technique used to deposit local anesthetic solution adjacent to the nerve. STUDY DESIGN: Prospective experimental study. ANIMALS: Adult equine cadaver heads (n=6 for preliminary dissection; n=15 [30 nerve sites] for evaluation of injection technique). METHODS: Preliminary dissections were performed to identify landmarks for injection of local anesthetic adjacent to the ethmoidal nerve. For evaluation of the injection technique a 20 gauge 6 cm spinal needle was inserted into the rostromedial aspect of the supraorbital fossa, where the caudal aspect of the zygomatic process emerges from the frontal bone caudal and medial to the globe. The needle was inserted to its hub at an angle of 110° to the long axis of the head using a protractor, in both a sagittal plane and a transverse plane, and 0.5 mL of new methylene blue dye was injected as a marker. The ethmoidal nerve was identified by dissection immediately after each injection and inspected for proximity of the dye. RESULTS: Dye was observed surrounding the nerve in 27 of 30 sites (90%) or lying within 5 mm of the nerve at the other 3 sites. CONCLUSION: The described technique of perineural injection of the ethmoidal nerve proved reliable and simple. Anesthetizing the ethmoidal nerve may be helpful in desensitizing portions of the ipsilateral paranasal sinuses and nasal cavity innervated by the nerve when sinonasal surgery is performed in the standing horse.

Magnetic resonance imaging features of progressive ethmoid hematoma in 2 horses.

Progressive ethmoid hematoma is frequently reported among the pathologies of the upper airways in horses. While several hypotheses have been proposed such as repeated trauma, inflammatory processes and/or chronic infections, congenital phenomena, complication of hemangiomas, and neoplastic processes, the aetiology of this condition is yet unknown. Clinical symptoms are non-specific and includes haemorrhagic nasal discharge, respiratory noise not related to physical exercise and, in most severe cases, phenomena of coughing. The purpose of this case report is to contribute to a correct diagnostic approach to this particular pathology of upper respiratory tract in horses. Magnetic Resonance allows for a very detailed imaging of the development of the disease and suggests appropriate therapeutic choices.

Tomography, Radiography, and Rhinoscopy in Diagnosis of Benign and Malignant Lesions Affecting the Nasal Cavity and Paranasal Sinuses in Dogs: Comparative Study.

Canine nasal and paranasal diseases have variable causes. Presumptive diagnosis is based on clinical manifestations; however, high similarity of clinical signs often calls for diagnostic imaging modalities and rhinoscopy before a definitive diagnosis can be reached. This study sets out to determine the value of rhinoscopy, radiography, and computed tomography (CT) of the head for canine nasal and paranasal disease diagnosis using a purposely developed comparative score. In all, 20 dogs presenting with clinical signs consistent with nasal disease were used. Patients were submitted to radiographic, CT, and rhinoscopic assessment; rhinoscopy-guided biopsy collection was performed in cases presenting with tissue proliferation, ulceration, or other nasal mucosal lesions. Rhinoscopy and rhinoscopy combined with CT significantly contributed to nasal disease diagnosis. Rhinoscopy and CT are complementary diagnostic modalities. Rhinoscopy proved helpful for confirmation of presumptive diagnosis and allowed image-assisted biopsy collection whereas CT contributed to effective determination of lesion extension and involvement of adjacent structures. Yet, histologic confirmation remains vital for definitive diagnosis.

Magnetic resonance imaging characteristics of equine head disorders: 84 cases (2000-2013).

The equine head is an anatomically complex area, therefore advanced tomographic imaging techniques, such as computed tomography or magnetic resonance imaging (MRI), are often required for diagnosis and treatment planning. The purpose of this multicenter retrospective study was to describe MRI characteristics for a large sample of horses with head disorders. Horses imaged over a period of 13 years were recruited. Eighty-four horses met the inclusion criteria, having neurological (n = 65), sinonasal (n = 14), and soft tissue (n = 5) disorders. Magnetic resonance imaging accurately depicted the anatomy and allowed identification of the primary lesion and associated changes. There were good correlations between MRI findings and intraoperative or postmortem results. Magnetic resonance imaging showed the exact localization of the lesions, their size, and relation to surrounding structures. However, in the neurological group, there were 45 horses with no MRI abnormalities, 29 of which had a history of recurrent seizures, related to cryptogenic epilepsy. Magnetic resonance imaging was otherwise a valuable diagnostic tool, and can be used for studying a broad range of head disorders using either low-field or high-field magnets.

Headshaking in 5 horses after paranasal sinus surgery.

OBJECTIVE: To report headshaking and presumptive trigeminal neuritis as a potential complication after paranasal sinus surgery in horses. STUDY DESIGN: Retrospective case series. ANIMALS: Horses (n = 5) that developed headshaking within 45 days of paranasal sinus surgery. METHODS: Medical records (2007-2010) of horses that had been evaluated for headshaking after paranasal sinus surgery were reviewed. RESULTS: Of 5 horses that developed headshaking within 45 days of paranasal sinus surgery, resolution occurred after treatment in 2 horses. One horse was euthanatized because clinical signs associated with headshaking could not be controlled. Headshaking persisted in the other 2 horses but was either adequately controlled with analgesics or was considered infrequent and transient enough to not warrant therapeutic intervention. Only 2 of 5 horses returned to full work after development of headshaking. CONCLUSIONS: Headshaking because of presumptive trigeminal neuritis is a possible career-ending or fatal complication of paranasal sinus surgery in horses.

Bacterial meningitis after sinus surgery in five adult horses.

OBJECTIVE: To report meningoencephalitis as a complication after paranasal sinus surgery in 5 horses. STUDY DESIGN: Case series. ANIMALS: Adult horses (n = 5). METHODS: Medical records (2005-2010) of 5 horses that developed neurologic signs after sinus surgery were reviewed to identify potential risk factors, cause(s), or common pathways for infection. RESULTS: Underlying diseases were primary (n = 1) and secondary sinusitis (4) because of apical dental infection (1), sinus cyst (2), or masses in the ethmoturbinate region (2). Horses were treated by conventional surgical approaches and aftercare including repeated sinus lavage. Four horses had undulating pyrexia postoperatively despite antimicrobial therapy. All horses developed neurologic signs, eventually unresponsive to treatment. Suppurative meningoencephalitis was diagnosed macro- and/or microscopically on necropsy in all horses. CONCLUSION: Meningitis is a rare but fatal complication after sinus surgery in horses.

New ways to diagnose and treat equine dental-related sinus disease.

The diagnosis and treatment of equine dental-related sinus disease is often challenging. Dental-related sinus disease is common and knowledge of these diseases is becoming increasingly important in veterinary medicine. Diagnostic capabilities are continually improving, leading to early diagnostic and therapeutic successes. With advanced imaging modalities, such as computed tomography and magnetic resonance imaging, understanding of the intimate anatomic relationship between teeth and the paranasal sinuses continues to progress. There are many therapeutic options available for the treatment of these common and challenging disorders. A complete understanding of the disease, therapeutic options, and potential complications is vital to overall successful resolution of clinical signs in equine dental-related sinus disorders.

A single caudally based frontonasal bone flap for treatment of bilateral mucocele in the paranasal sinuses of an American miniature horse.

OBJECTIVE: To describe successful surgical treatment of bilateral mucocele in an American Miniature horse using a single bone flap to approach right and left paranasal sinuses simultaneously. STUDY DESIGN: Clinical report. ANIMAL: A castrated 6-year-old American Miniature Horse with a bilateral mucocele of the paranasal sinuses. METHODS: A single bilateral frontonasal sinus flap was used in a standing procedure to access the left and right conchofrontal sinuses simultaneously to remove the mucous contents and to establish permanent drainage into the nasal cavities. RESULTS: The novel procedure used in this horse allowed excellent access to right and left paranasal sinuses simultaneously and completely resolved nasal discharge and difficulty breathing. CONCLUSIONS: A single, bilateral frontonasal sinus flap can be used successfully as a standing procedure to treat bilateral sinonasal disease in horses.

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.

[Chronic diseases of the nose and nasal sinuses in cats: a retrospective study]. / Chronische Erkrankungen der Nase und Nasennebenhöhlen der Katze: Eine retrospektive Studie.

In this retrospective study of 41 cats with chronic nasal disease diagnoses included nasal neoplasia (n = 19), idiopathic chronic rhinosinusitis (ICRS) (n = 12), nasopharyngeal polyps (n = 3), foreign bodies (n = 2), nasopharyngeal stenosis (n = 1) and nasal aspergillosis (n = 1). In 3 cats diagnosis could not be established despite thorough work-up. Gender, indoor or outdoor housing, quality or quantity of nasal discharge, bacteriological findings of nasal flushes, radiology and CT findings did not differ significantly between cats with neoplasia and cats with ICRS. Cats with neoplasia were older (3 - 15, median 11 years) and showed clinical signs for a shorter period of time (1 - 8, median 2 months) than cats with ICRS (age 1 - 13, median 7.5 years; signs: 1 - 36, median 5 months). In all cats with neoplasia a mass was detected rhinoscopically, while this was only seen in 30 % of cats with ICRS. The exact diagnosis has to be established by examination of biopsy samples. A combination of physical examination, imaging studies and rhinoscopy with cytological and histopathological examination of samples enhances the likelihood for a correct diagnosis.

Equine paranasal sinus disease: a long-term study of 200 cases (1997-2009): ancillary diagnostic findings and involvement of the various sinus compartments.

REASONS FOR PERFORMING STUDY: There is a lack of objective information on the value of ancillary diagnostic techniques used to investigate equine sinus disease, and also on which sinus compartments are commonly affected in this disorder. OBJECTIVES: To record the ancillary diagnostic findings used to investigate equine sinus disease and to document which compartments are affected. MATERIALS AND METHODS: The clinical case records of 200 consecutive cases of sinus disease, including subacute (<2 months' duration) primary (n = 52); chronic (>2 months' duration) primary (n = 37); dental (n = 40); traumatic (n = 13); sinus cyst (n = 26); sinus neoplasia (n = 10); dental related oromaxillary fistula (n = 8); mycotic sinusitis (n = 7) and intra-sinus progressive ethmoid haematoma (n = 7) were retrospectively examined. RESULTS: Nasal endoscopy showed exudate draining from the sino-nasal ostia in 88% of cases and a sino-nasal fistula was present in 15% of cases. Sinoscopy was performed in 79% of cases and was of great diagnostic value. More recently, 22% of cases had fenestration of the ventral conchal bulla performed to allow sinoscopy of the rostral sinus compartments. Radiography was performed in 97% of cases and showed intra-sinus fluid lines to be common (69% prevalence) in subacute primary sinusitis. Radiographic dental apical changes were not specific to dental sinusitis, e.g. 29% of chronic primary sinusitis cases had radiographic dental changes. Scintigraphy was performed in 20% of cases and was helpful in identifying dental apical changes when radiography was inconclusive. Overall, the caudal maxillary (78% involvement) and rostral maxillary (61%) sinuses were most commonly affected, with the ventral conchal sinus (VCS) (54% involvement) and conchofrontal sinuses (48%) less so. The VCS showed the greatest tendency to contain inspissated pus (present in 46% of all affected VCS). CONCLUSIONS: Nasal endoscopy, sinoscopy and skull radiography are of great value in diagnosing the presence and causes of equine sinus disease.