Modified lateral orbitotomy for vision-sparing excision of a zygomatic mucocele in a dog

A 1-year-old Shar Pei presented for recent-onset exophthalmos and right peri-ocular facial swelling. Physical examination revealed the facial mass was of soft-tissue consistency and nonpainful to the dog. Due to inability to retropulse the globe during ophthalmologic examination, it was suspected the mass had impinged into the orbit, resulting in rostral displacement of the globe. Anatomic location suggested the lesion was probably associated with the zygomatic salivary gland. Fine-needle aspiration and subsequent cytological evaluation of fluid extracted from the facial mass was consistent with a diagnosis of zygomatic mucocele. Computed tomography imaging confirmed a single fluid-filled mass was resulting in both the facial distention and the exophthalmos. A modified, lateral orbitotomy surgical approach was selected for excision of the lesion to provide ventral exposure to the orbit, while minimizing trauma to the globe and supporting structures. Histopathology of the excised lesion confirmed a diagnosis of zygomatic mucocele. This case demonstrates utilization of a modified lateral orbitotomy for effective surgical management of a zygomatic mucocele in a dog, with preservation of vision and absence of any significant postoperative complications.     

Zygomatic salivary gland mucocele in a ferret

A zygomatic salivary gland mucocele was diagnosed in a 1-year-old female domestic ferret with exophthalmos. A T-shaped incision from near the lateral canthus to the base of the ear and continuing ventrally to the level of the commissure of the mouth was made to expose the mucocele. Surgical removal was complicated by the large open orbit of the ferret, adjacent cellulitis, extension ventromedial to the globe, and difficulty in identifying important motor nerves. Vision was maintained, but slight postoperative enophthalmos and mild upper eyelid paresis developed.     

Botulinum toxin A as a treatment for delayed gastric emptying in a dog

A toy Australian shepherd dog was referred for bile peritonitis following excision of a biliary mucocele. Subsequent delayed gastric emptying was refractory to prokinetic therapy but responded to injection of botulinum toxin A into the muscularis layer of the pylorus; a novel therapy for delayed gastric emptying in dogs.     

CLINICAL AND ULTRASONOGRAPHIC CHARACTERISTICS OF SALIVARY MUCOCELES IN 13 DOGS

Salivary mucocele is one of the causes of submandibular swelling in dogs and is due to a collection of mucoid saliva that has leaked from a damaged salivary gland. The purpose of this case series report was to describe the clinical and ultrasonographic characteristics of confirmed salivary mucoceles in 13 dogs admitted to the Faculty of Veterinary Medicine at Cairo University. The final diagnosis of salivary mucocele was based on aspirate cytology for all dogs and additional surgical excision for seven dogs. For dogs admitted from 2 weeks to 1 month from the onset of clinical signs, the cervical mucocele appeared as a round echogenic structure with a large volume of central anechoic content. The wall was a clearly identified hyperechoic structure surrounding the gland. For dogs admitted between 1 to 2 months from the onset of clinical signs, the volume of anechoic material appeared less than that seen in the acute cases. The overall appearance of the salivary mucocele was heterogenous. For dogs admitted after 2 months from the onset of clinical signs, the salivary mucocele appeared grainy or mottled, with a heterogenous appearance and a further decrease in anechoic content. For one dog that presented after 3 months from the onset of clinical signs, the salivary mucocele was hard on palpation and appeared hyperechoic with distal acoustic shadowing. Findings from this study indicated that ultrasonographic characteristics of salivary mucoceles in dogs vary depending on the chronological stage of the disease.     

Congenital duplex gallbladder and biliary mucocele associated with partial hepatic cholestasis and cholelithiasis in a cat

A 6-year-old neutered male domestic shorthair cat was presented for acute onset of vomiting. Exploratory laparotomy identified a duplex gallbladder and left cholecystectomy was performed. Histopathology confirmed biliary mucocele and hepatic cholestasis. While rare, biliary mucoceles should be considered as a differential diagnosis for feline extrahepatic bile duct obstruction.     

Gall bladder mucoceles and their association with endocrinopathies in dogs: a retrospective case‐control study

Objective : To investigate the relationship between endocrinopathies and diagnosis of gall bladder mucocele in dogs via a retrospective case‐control study. Methods : Records of 78 dogs with a surgical or ultrasonographic diagnosis of gall bladder mucocele were examined for the presence or absence of hyperadrenocorticism, hypothyroidism and diabetes mellitus. Two age‐ and breed‐matched controls for each gall bladder mucocele dog (156 total control dogs) were examined for the same concurrent diseases. A matched case‐control analysis was performed using conditional logistic regression. Results : The odds of mucocele in dogs with hyperadrenocorticism were 29 times that of dogs without hyperadrenocorticism (P=0·001; 95 per cent CI 3·8, 219·9). No difference was found between dogs with and without diabetes mellitus. Although a significant association was found between gall bladder mucocele and hypothyroidism, potential observation bias was also identifi ed. Clinical Significance : Hyperadrenocorticoid dogs that were presented for acute illness with laboratory evidence of hepatobiliary disease should undergo evaluation for the presence of a biliary mucocele. Dogs diagnosed with a gall bladder mucocele should be screened for concurrent hyperadrenocorticism if clinical suspicion exists.     

Taenia serialis causing exophthalmos in a pet rabbit

A 16-month-old, male, neuter Dwarf Lop rabbit presented with exophthalmos of the right eye of 3 weeks duration. Under sedation an ultrasound of the right eye was performed and showed an orbital hypo-echoic area posterior and ventrolateral to the right globe, which was presumed to be a cyst. Fine needle aspirate removed 5.5 mLs of straw-colored fluid from the cyst, which allowed the globe to return to its normal position. Two months later the rabbit re-presented with exophthalmos of the right eye. Exploratory surgery was performed and a large cystic structure was removed from the ventro-lateral conjunctival fornix. Histology confirmed the cyst to be a coenurus of Taenia serialis.     

Nonsurgical resolution of gallbladder mucocele in two dogs

CASE DESCRIPTION: A gallbladder mucocele was diagnosed in 2 dogs. In both dogs, the mucocele resolved with medical treatment but without the need for surgical intervention. CLINICAL FINDINGS: A 12-year-old spayed female Miniature Schnauzer had a history of signs of gastrointestinal tract disease and high serum liver enzyme activities. Gallbladder mucocele and hypothyroidism were diagnosed. A 6-year-old neutered mixed-breed dog had chronic intermittent diarrhea and recurrent otitis; gallbladder mucocele and hypothyroidism were diagnosed. TREATMENT AND OUTCOME: The first dog was treated with S-adenosyl-methionine, omega-3 fatty acids, famotidine, ursodiol, and levothyroxine. Substantial improvement in the gastrointestinal tract condition and complete resolution of the gallbladder mucocele within 3 months were evident, but the dog was not available for further follow-up monitoring. The second dog was treated with fenbendazole, ursodiol, and levothyroxine and fed a hypoallergenic diet. One month after evaluation, abdominal ultrasonography revealed that the gallbladder mucocele was resolving, and treatment was continued. Ultrasonographic evaluation 2 and 4 months later revealed complete resolution of the mucocele. CLINICAL RELEVANCE: Review of the clinical course of 2 dogs in which there was nonsurgical resolution of gallbladder mucocele revealed that surgery is not necessary in all dogs with gallbladder mucocele. Hypothyroidism may have resulted in delayed gallbladder emptying, and its role in the pathogenesis of gallbladder mucocele merits investigation. Despite this information, until further prospective trials with a control group and standardized treatments and follow-up monitoring can be performed, the authors recommend surgical intervention for treatment of dogs with gallbladder mucocele.     

First case of salivary mucocele originating from the minor salivary gland of the soft palate in a dog

We found a case of salivary mucocele that originated in the minor salivary gland (palatine gland) of the soft palate in a dog. At first admission, the soft palate swelled remarkably. Computed tomography (CT) revealed cystic radiolucency inside a large quantity of liquid in the soft palate, and most of the airway was occupied. Marsupialization was performed, but since a recurrence was observed one month later, the salivary mucocele was removed. There has been no report of salivary mucocele arising from the minor salivary gland of the soft palate in dogs. To our knowledge, this case is the first. Complete removal, including minor salivary glands surrounding the lesion, is necessary for treatment of salivary mucocele in dogs.     

Zygomatic salivary cyst with mucocele formation in a cat

An eight-year-old neutered male domestic shorthalr cat had a zygomatlc salivary cyst with associated mucocele formation. A fluctuating swelling developed ventral to the right eye, causing bulging of the lower eyelid, and a corresponding swelling was present in the caudal vestibule of the oral cavity. Cytological examination of the fluid obtained from asplratlon of the swelling was consistent with the appearance of saliva. A tentative dlagnosls of zygomatlc salivary mucocele was made. Surgical exploration and resectlon of the swelling demonstrated the presence of a multliobular cystic zygomatlc salivary gland. The histopathological appearance of the resected tissue was Interpreted as an Inflammatory reaction to mucus derived from a muitllocular salivary cyst.     

Bilateral uveal metastasis of a subcutaneous fibrosarcoma in a cat

A 6‐year‐old neutered male domestic short‐haired cat was presented to the Comparative Ophthalmology service at Michigan State University with a 3‐week history of decreased appetite and redness of the left eye. The left forelimb had been removed 15 months previously because of the presence of a subcutaneous fibrosarcoma. In the left globe, a large iridal mass was associated with increased intraocular pressure and retinal detachment. A smaller mass involving the right iris was also present. Imaging revealed a 2‐cm mass in the left caudodorsal lung lobe, and abdominal ultrasound showed multifocal bilateral renal masses. Aspirates of these masses were nondiagnostic. The left globe was removed for palliative reasons, and histopathology showed that fibrosarcoma was infiltrating the iris, choroid, and optic nerve. Despite systemic chemotherapy with doxorubicin, the animal died 4 months after initial presentation. Histopathology confirmed highly angioinvasive metastatic fibrosarcoma also in the right uveal tract, the lungs, and both kidneys.     

Exophthalmus secondary to a sinonasal cyst in a horse

CASE DESCRIPTION: A 13-year-old female Miniature Horse was evaluated for progressive unilateral exophthalmia of the left globe of 3 weeks' duration. CLINICAL FINDINGS: Results of a physical examination were unremarkable. Ophthalmic examination identified exophthalmus of the left globe with complete resistance to retropulsion and mild blepharoconjunctivitis. Computed tomography revealed a large, space-occupying mass within the left caudal maxillary and left conchofrontal sinuses. The mass extended into the left retrobulbar space and contacted the cribriform plate. Trephination yielded copious amounts of turbid yellow fluid. The diagnosis was a sinonasal cyst. TREATMENT AND OUTCOME: Subtotal surgical excision of the cyst via a frontonasal osteoplastic flap was curative, with complete resolution of the exophthalmus. Histologic examination confirmed diagnosis of a sinonasal cyst. There was no evidence of cyst recurrence by 4 months after surgery. CLINICAL RELEVANCE: Sinonasal cyst should be a differential diagnosis for retrobulbar disease in horses. Exophthalmia may be the only clinical finding in horses with a sinonasal cyst.     

Pharyngeal mucoceles in dogs: 14 cases

This report describes the clinical features of a series of dogs with pharyngeal salivary mucoceles. A retrospective study of 14 dogs with pharyngeal mucocele was performed. Medical records from 1983 to 2003 were reviewed for information regarding signalment, clinical signs, diagnosis, surgical procedures, and short-term and long-term outcome. Miniature and toy poodles were common breeds in the study population, and 79% of the dogs were male. The most common presenting sign was dyspnea (50%). Diagnosis was by fine-needle aspirate, which revealed a mucoid substance in 93% of dogs. Histopathology of the excised salivary glands revealed lymphoplasmacytic inflammation in all dogs that had histopathology performed. Forty-three percent of the dogs had a cervical mucocele on the same side as the pharyngeal mucocele. Surgical therapy was performed in 13 dogs, which consisted of excision of the mandibular and sublingual salivary glands, excision of the mucocele, or marsupulization of the mucocele. Only two dogs had recurrence of the pharyngeal mucocele. In this study, pharyngeal mucoceles occurred in predominantly small dogs that frequently presented with respiratory signs. Surgical treatment was successful in most dogs.     

Decreased gallbladder emptying in dogs with biliary sludge or gallbladder mucocele

Biliary sludge in dogs is dismissed commonly as an incidental finding. On the other hand, gallbladder mucocele is reported increasingly in dogs and can lead to biliary obstruction or gallbladder rupture. Cholestasis is suspected to play a role in development of sludge and mucoceles, though there are no data in dogs to support this. We investigated gallbladder emptying, a key factor in biliary flow, in dogs with mobile sludge, immobile sludge, or gallbladder mucocele and in healthy controls. Gallbladder ejection fraction estimated by ultrasonography was used as the index of gallbladder emptying. The ejection fraction at 60 min after eating was significantly decreased in all three abnormal groups. Moreover, all dogs with sludge or a mucocele had gallbladder distension. These changes were the greatest in the mucocele group. Thus, biliary stasis occurs not only in dogs with gallbladder mucocele but also in dogs with biliary sludge. Cholestasis may play a role in the pathogenesis or progression of these diseases in dogs.     

Sinus mucocele secondary to craniofacial trauma in a dog

A sinsus mucocele formed in the frontal sinus of a dog secondary to obstruction of the nasofrontal opening. The dog was successfully treated by surgical enlargement of the nasofrontal opening, curettage of the sinus epithelium, and placement of a fat graft and drain in the sinus. Although mucocele formation is uncommon in animals, it should be considered as a differential diagnosis for masses of the sinonasal area. Characteristic radiographic and cytologic findings should alert the clinician to this diagnosis, and along with aggressive treatment, should shorten the diagnostic and treatment delay experienced by the dog in this report.     

Retrobulbar rhabdomyosarcoma in a neotropical peregrine falcon (Falco peregrinus cassini)

A mild swelling of the left periorbital was detected on a routine physical exam of a healthy captive adult peregrine falcon. Despite treatment, the swelling did not subside and within twenty‐five days was causing significant exophthalmia and medial deviation of the left globe. A retrobulbar fusiform cell sarcoma was diagnosed with histopathology, then light microscopy and immunohistochemical staining confirmed the diagnosis of a rhabdomyosarcoma.     

CT attenuation values and mineral distribution can be used to differentiate dogs with and without gallbladder mucoceles

Gallbladder mucoceles are potentially fatal in dogs. Multiphase CT angiography was performed to evaluate the canine gallbladder in three conditions: no sludge, sludge occupying ≥25% of the lumen, and mucoceles. Twenty dogs with normal hepatobiliary bloodwork and no‐to‐minimal gallbladder sludge, 13 dogs with normal bloodwork and ≥25% sludge in the gallbladder lumen, and 18 dogs with histologically confirmed gallbladder mucoceles were enrolled in a prospective, observational diagnostic accuracy study. Three regions of interest (ROI) were stratified in the dorsal‐ventral orientation and a single ROI was measured within the hepatic parenchyma. Mean attenuation and presence of mineral were recorded. Average Hounsfield units (HU) were recorded for precontrast, arterial, portovenous, and late venous phases. The overall median HU value for mucoceles was significantly higher than gallbladders without sludge and with sludge; precontrast median overall attenuation was 49.3, 35.8, and 39.7 HU, respectively (P < .000004). Mineral was seen in four (20%) dogs with no sludge, seven (56%) dogs with sludge, and nine (50%) dogs with mucoceles. Mineral in the dogs with mucoceles was located within the central aspect of the gallbladder lumen in 67% of mucoceles; this mineral distribution was not seen in any dog without a mucocele. Computed tomography can differentiate a subset of gallbladder mucoceles from dogs with and without gallbladder sludge, especially in the precontrast series. An HU value of 48.6 is 52% sensitive and 96% specific for a gallbladder mucocele. A hyperattenuating gallbladder on precontrast CT images and centrally distributed mineral can be a gallbladder mucocele.     

Gallbladder disease in Shetland Sheepdogs: 38 cases (1995-2005)

OBJECTIVE: To determine risk, clinical features, and treatment responses for gallbladder disorders in Shetland Sheepdogs. DESIGN: Retrospective case-control study. ANIMALS: 38 Shetland Sheepdogs with gallbladder disease. PROCEDURES: Medical records were reviewed for signalment, history, physical findings, laboratory results, imaging features, coexistent illnesses, histologic findings, treatments, and survival rates. RESULTS: Mature dogs with gastrointestinal signs were predisposed (odds ratio, 7.2) to gallbladder disorders. Gallbladder mucocele was confirmed in 25 dogs. Concurrent problems included pancreatitis, hyperlipidemia, corticosteroid excess, hypothyroidism, protein-losing nephropathy, diabetes mellitus, cholelithiasis, and gallbladder dysmotility. Mortality rate was 68% with and 32% without bile peritonitis. Nonsurvivors had high WBC and neutrophil count and low potassium concentration. Although preprandial hypercholesterolemia, hypertriglyceridemia, and high serum liver enzyme activities were common, gallbladder disease was serendipitously discovered in 11 of 38 dogs. Histologic examination (n=20 dogs) revealed gallbladder cystic mucosal hyperplasia in 20 dogs, cholecystitis in 16, periportal hepatitis in 9, and vacuolar hepatopathy in 7. Surgery included cholecystectomy (n=17) and cholecystoenterostomy (4). In 1 hyperlipidemic dog without clinical signs, gallbladder mucocele resolved 6 months after beginning use of a fat-restricted diet and ursodeoxycholic acid. CONCLUSIONS AND CLINICAL RELEVANCE: Shetland Sheepdogs are predisposed to gallbladder disorders, with mucoceles and concurrent dyslipidemia or dysmotility in many affected dogs. Most dogs were without clinical signs during mucocele development. Low survival rate after cholecystectomy in clinically affected dogs suggested that preemptive surgical interventions may be a more appropriate treatment strategy.     

Surgical management of orbital nodular granulomatous episcleritis in a dog

A 27 kg, 6‐year‐old, male castrated German shorthaired pointer presented to the University of Missouri, Veterinary Teaching Hospital with the complaint of progressive exophthalmia of 2 years duration optical density (OD). Lack of retropulsion OD was noted on physical examination. Anterior segment examination OU and fundic examination OS did not reveal any abnormalities. Examination of the fundus OD revealed focal scleral indentation of the inferior nasal globe. The indentation changed location with globe movement OD. MRI and CT scan revealed a well‐circumscribed, approximately 2 cm in diameter mass located caudal and ventral to the affected globe that appeared to communicate with the nictitating membrane with absence of any bony involvement. A modified lateral orbitotomy was recommended and performed to remove the orbital mass and nictitating membrane en‐bloc. Histopathology and immunohistochemistry of the mass confirmed a diagnosis of nodular granulomatous episcleritis (NGE). Postoperatively, the dog developed absolute keratoconjunctivitis sicca (KCS). Examples of primary episcleral inflammation in the dog include diffuse episcleritis, NGE, nodular fasciitis, fibrous histiocytoma, proliferative conjunctivitis/keratoconjunctivitis, pseudotumor, and Collie granuloma. The etiology of these episcleral inflammations is presumed to be immune mediated. To our knowledge, this is the first report of NGE affecting the orbital region of a dog. Development of absolute KCS resulting from excision of the nictitating membrane is also supported by this case.     

Penetrating sclerokeratoplasty and autologous pinnal cartilage and conjunctival grafting to treat a large limbal melanoma in a dog

A four‐year‐old neutered male Labrador retriever presented to Portland Veterinary Specialists Ophthalmology Service for evaluation of a pigmented mass oculus sinister (OS) of approximately 4‐month duration. Complete ophthalmic examination revealed a large, pigmented, raised, well‐demarcated, epibulbar mass appearing to originate from the nasodorsal limbal region. The mass was smooth and roughly circular, extending approximately 4 mm into the sclera and 14 mm into the nasodorsal cornea. Gonioscopy directly under the mass was not possible due to mass size. The visible iridocorneal angle was normal. High‐resolution B‐scan ultrasound showed mass extension to Descemet's membrane and deep sclera, but no intraocular invasion. Penetrating sclerokeratoplasty was performed followed by autologous pinnal cartilage and conjunctival grafting to repair the corneoscleral defect (20 mm x 19 mm) and to restore globe integrity and function. Histopathology confirmed the mass to be a benign limbal melanoma with complete excision. The surgery site healed without complication, and the pinnal cartilage became fully incorporated into the globe. Twelve months postoperatively, the patient remains visual with a normal intraocular and fundic examination. The pinnal harvest site on the right ear healed without complication. To the authors’ knowledge, this is the first reported case of corneoscleral grafting using autologous pinnal cartilage. This may represent a viable alternative to other corneoscleral grafting procedures for large defects and is an attractive treatment option due to lack of host rejection, readily available source of donor cartilage, and provision of tectonic support to the globe.