Rhabdomyosarcoma of the tongue in a dog

A lingual rhabdomyosarcoma was diagnosed in a six-year-old Staffordshire bull terrier with clinical signs of dysphagia. The unsuccessful response to initial chemotherapy, to surgical resection and subsequent surgical resection and radiation therapy is documented. The accurate diagnosis and prognosis of such tumours is also discussed. Lingual rhabdomarcoma has not previously been reported in the dog.     

Thoracic actinomycosis (arcanobacteriosis) or nocardiosis causing thoracic pyogranuloma formation in three dogs

OBJECTIVE: To describe three cases of canine thoracic actinomycosis (arcanobacteriosis) or nocardiosis in which the primary pathological lesion was a pyogranulomatous abscess in the mediastinum. Clinical signs, difficulties in diagnosis, treatment and prognosis are examined. Comparisons are made between human and veterinary literature to assist in formulating a rational treatment plan. DESIGN: Retrospective clinical study. PROCEDURE: Review of case records from 1984 to 1998. RESULTS: Three dogs presented with large intrathoracic pyogranulomas producing variable clinical signs, not necessarily associated with the respiratory tract. Ages ranged from 2 to 5 years old. Two dogs responded to surgical opening and passive drainage of the abscess, or surgical excision of the granuloma with associated structures, and medical therapy. One dog died intra-operatively. CONCLUSION: A combination of surgical and antimicrobial therapy may carry a fair-to-good prognosis for thoracic granuloma caused by actinomycosis (arcanobacteriosis) or nocardiosis. The extent of surgery should be based on assessment of individual cases and must include surgical biopsy for histology and culture to enable a specific diagnosis to be made. Complete surgical excision is not necessarily required. Prolonged antimicrobial therapy is indicated.     

Immunohistochemical characterization of a malignant intraocular teratoid medulloepithelioma in a cockatiel

A 3-year-old cockatiel was presented for evaluation of a buphthalmic right eye (OD). The history included a traumatic event 5 months prior to presentation, and the referring veterinarian diagnosed cataract and secondary glaucoma. Computed tomography of the bird's orbital region revealed a large right orbital soft tissue mass that extended lateral to the orbital rim with obliteration of the globe without bone involvement. There was also no evidence of metastatic disease within the lungs or any abnormalities within the celomic cavity, therefore enucleation was recommended to achieve a histopathologic diagnosis and prognosis, and to palliate the clinical signs. Final diagnosis was malignant intraocular teratoid medulloepithelioma.     

Nocardiosis

Two dogs with systemic nocardiosis are presented and the pathobiology, diagnosis, and treatment of nocardial infections are discussed. Both dogs had nonspecific respiratory signs and depression. The diagnosis was made by isolation of the organism only after surgical drainage was established and appropriate tissues were cultured. The response to surgical drainage and antimicrobial therapy was dramatic in both dogs, but one dog experienced a drug reaction to trimethoprim-potentiated sulfonamide. Although systemic nocardial infections traditionally have had a grave prognosis, through early diagnosis, surgical intervention, and the use of newer, safer and synergistically acting antimicrobials, the prognosis has improved. This article reviews current human and veterinary literature regarding the microbiology, pathogenesis, and treatment of nocardiosis and reports on the successful treatment of systemic nocardiosis in two dogs.     

Ophthalmomyiasis interna anterior in a dog: keratotomy and extraction of a Cuterebra sp. larva

A 1‐year‐old female spayed mixed‐breed dog was presented for evaluation of acute onset of lethargy and blepharospasm OD. Slit‐lamp biomicroscopy revealed a segmented larva embedded in the inferonasal iris. Moderate anterior uveitis was present. After pharmacologic dilation, mild vitreal hemorrhage and chorioretinal migration tracks were identified. The dog was treated empirically for uveitis for 5 days, after which a keratotomy and larval foreign body extraction was performed. The dog recovered uneventfully from intraocular surgery and remained visual and comfortable. Parasite evaluation confirmed the larva to be a Cuterebra sp. To the authors’ knowledge, this is the first report of canine ophthalmomyiasis interna anterior, and the first report of successful surgical removal from the anterior segment in a dog with preservation of vision.     

Orbital cellulitis and intraocular abscess caused by migrating grass in a cat

We report an unusual case of orbital cellulitis in a cat. Drainage via the pterygopalatine fossa and medical treatment were performed. Failure of resolution and loss of ocular structure and visual function with a poor prognosis led to enucleation. During surgery, plant material and purulent exudate were present in the orbit. Histopathology showed an intraocular foreign body of grass that had migrated through the sclera causing a suprachoroidal abscess with choroidal and retinal detachment.     

Equine orbital neoplasia: a review of 10 cases (1983-1998)

The clinical manifestations, laboratory findings, and survival times of 10 horses with orbital neoplasms are reported. In all cases, orbital neoplasms were malignant and locally invasive with no defined surgical circumscribed edges. It was often difficult to identify the primary cell type of the neoplasia in histologic specimens due to the poorly differentiated, anaplastic nature of the majority of cases. All except one horse were eventually euthanized 2 mo to 5 y after diagnosis due to poor response to treatment, metastasis, or unrelenting orbital neoplasia. Mean survival time increased with surgical treatment, but no significant difference was found among no treatment, chemotherapy, surgical mass removal, or exenteration/enucleation. Equine practitioners should be aware of the marked difference in prognosis of orbital neoplasms compared with ocular or localized eyelid neoplasia.     

The surgical treatment of canine glaucoma

The success of glaucoma therapy depends wholely upon the ability to restore rapidly an elevated intraocular pressure to normal, and subsequently to maintain adequate aqueous drainage. In the dog, the extent of synechial occlusion within the iridocorneal angle is often such that medical therapy proves to be of little or no lasting value, and a surgical approach is essential if ocular structure and function are to be preserved. The author has recently evaluated several techniques of glaucoma surgery in sixty-one patients, and his results now indicate that corneoscleral trephination combined with peripheral iridectomy offers the greatest chance of success in the treatment of this condition.     

Porcupine quills in raccoons as an indicator of rabies, distemper, or both diseases: disease management implications

A relationship was detected between the presence of embedded porcupine quills and the diagnosis of rabies in raccoons in eastern Canada during 1999-2004. No relationship was found between the presence of quills in raccoons and the diagnosis of canine distemper. Raccoons with embedded quills should be submitted for rabies testing.     

Ultrasonographic diagnosis of septic arthritis secondary to porcupine quill migration in a dog

A 7-year-old castrated male German Shepherd Dog was evaluated for lethargy, icterus, and sepsis. Porcupine quills had been removed from the dog's face 1 month prior to examination; progressive right forelimb lameness had developed soon after removal of the quills. Septic arthritis of the right elbow joint was diagnosed and was unresponsive to antimicrobial and anti-inflammatory treatments. At the time of referral, the dog had developed endocarditis, septicemia, and disseminated intravascular coagulation. Via ultrasonography, a foreign body consistent with a porcupine quill was detected in the medial portion of the right humeroradial joint. The dog did not respond to initial supportive treatment and died as a result of cardiac arrest. Postmortem examination confirmed the presence of a quill in the medial compartment of the right elbow joint and severe acute endocarditis with septic emboli to the kidneys and spleen. Ultrasonographic examination should be considered as a diagnostic tool when septic arthritis secondary to a foreign body is suspected in dogs.     

Choroidal melanoma in a dog

A 7-year-old intact female golden Retriever was referred for evaluation of an intraorbital mass of the left eye. Based on ophthalmoscopy, ultrasonography and magnetic resonance imaging (MRI), the tentative diagnosis was made as an intraocular neoplasia, especially choroidal melanoma. The orbital exenteration of the affected eye was performed. The mass was histologically diagnosed as malignant choroidal melanoma. No signs of recurrence and metastasis were detected by thoracic radiographs, blood examinations and MR images, and the dog was clinically healthy for 23 months after operation.     

Hyperthyroidism associated with a thyroid adenoma in a dog

Hyperthyroidism associated with thyroid adenoma was diagnosed in a dog. Typical clinical signs of hyperthyroidism were resolved with surgical excision of the adenoma. Hyperthyroidism in dogs usually is associated with thyroid carcinoma, which has a poor prognosis. This case emphasizes the importance of obtaining a histologic diagnosis of thyroid tumors in hyperthyroid dogs before giving a prognosis.     

The Treatment of Acute Glaucoma in Dogs and Cats

Objective: Glaucoma is an optic nerve disease that may result in rapid loss of vision. Early detection of acute glaucoma and aggressive treatment is important to preserve vision. Continued treatment is indicated in chronic glaucoma to alleviate discomfort associated with chronic elevated intraocular pressure.
Etiology: In primary glaucoma, an abnormal iridocorneal angle results in obstruction to outflow of aqueous humor. In secondary glaucoma, an otherwise normal iridocorneal angle is obstructed by abnormalities such as a luxated lens, neovascular membranes or inflammatory material.
Diagnosis: The diagnosis is made by a combination of clinical signs such as corneal edema, mydriasis, decreased vision, episcleral hyperemia, and confirmed by measuring an elevation in intraocular pressure. Complete ophthalmic examination, knowledge of breed predisposition to various ocular diseases and gonioscopy will aid in distinguishing between primary and secondary glaucoma
Therapy: Aggressive medical management is important in acute glaucoma. Surgical procedures are often indicated after initial emergency medical treatment of acute glaucoma. Chronic, painful blind eyes are best treated with one of various surgical procedures.
Prognosis: The prognosis for maintaining vision or regaining temporarily lost vision in acute glaucoma is related to numerous factors including time between onset of clinical signs and appropriate treatment, etiology of the glaucoma, initial response to therapy and client compliance.     

Extraskeletal osteosarcoma associated with retained surgical sponge in a dog.

Retained surgical sponges are usually discovered in the abdominal cavity, sometimes years after the surgical procedure, and the typical reaction is formation of a foreign-body granuloma, often called gossypiboma or textiloma. In this instance, an extraskeletal osteosarcoma, associated with the granulomatous reaction to a retained surgical sponge adjacent to the stifle, was diagnosed in an 11-year-old Labrador Retriever 9 years after repair of a ruptured cranial cruciate ligament. Radiographic detection of linear foreign material in the soft tissue mass was the basis for a diagnosis of gossypiboma. The mass was surgically excised. Histologically, fibers consistent with those of cotton gauze were associated with the granulomatous inflammation and the osteosarcoma. Amputation or radiation therapy was declined; the dog was treated conservatively with doxycycline and deracoxib. Three months after surgical excision, the dog was euthanized because of local recurrence of the mass along with lameness and decreased appetite.     

Thoracic, Abdominal and Vertebral Actinomycosis

The clinical, laboratory, radiographic, and histologic features and the response to therapy in three dogs with actinomycosis are reported. One dog (dog 1) had a 12-cm nonresectable mass extending from the ventrolateral chest wall into the left ventricular myocardium. Another dog (dog 2) had a diffuse peritonitis with "sulfur granules" and two large masses. One of these masses was nonresectable involving adjacent abdominal structures. A third dog (dog 3) had a subvertebral mass at T1-3 producing quadraplegia. Two dogs had periosteal reactions involving adjacent sternebrae (dog 1) or ribs and vertebral bodies (dog 3) that are characteristic of Actinomyces spp infections. In dogs 1 and 2 the diagnosis was based on the morphologic and tinctorial properties of free sulfur granules and/or tissue granules. Culture results were variable. Tissue from dog 1 yielded no growth, while polymicrobial infections, which included Actinomyces spp, were identified in dogs 2 and 3. Actinomyces odontolyticus was isolated from dog 3. Although the actinomycotic granulomas were either not excised or only partially excised from dogs 1 and 2, both animals were cured by the oral administration of high doses of penicillin G for 19 and 6 months, respectively. Dog 3 responded dramatically to the same antibiotic therapy given for 5 months. However, within 4 months of discontinuing treatment an abscess and draining fistulous tracts developed in the left axillary region. Two surgical fistulectomies and additional penicillin therapy were required to cure this animal. These cases and the current veterinary and human literature on actinomycosis are used to propose a rational approach to the treatment of actinomycosis in the dog.     

Doppler imaging of the ophthalmic vasculature of the normal dog: blood velocity measurements and reproducibility

The purpose of this study was to assess the feasibility and reproducibility of color Doppler imaging (CDI) of the vasculature of the normal canine orbit and eye. Eight normal Beagles were evaluated by Doppler imaging. The goals of the study were to determine the location, spectral waveform morphology, specific blood velocity parameters, and reproducibility for the ophthalmic and orbital vessels most frequently identified in the normal dog. Vessels identified a majority of the time (> 50%) included: external ophthalmic artery, dorsal external ophthalmic vein, ventral external ophthalmic vein, internal ophthalmic artery, anterior ciliary artery and vein, short and long posterior ciliary arteries, primary retinal arteries, and vortex veins. Other vessels imaged less frequently included: external ethmoidal artery (50%), and primary retinal veins (25%). For each blood vessel the time averaged velocity, peak systolic velocity, minimum diastolic velocity, pulsatility index, and resistive index were determined. The ophthalmic and orbital vessels have unique spectral waveforms and velocities which serve as a basis for identification. Reproducibility of the most commonly imaged vessels of the canine eye and orbit with Doppler imaging was high (< 10% variation). Doppler imaging has the potential for determining noninvasively and consecutively the blood velocity parameters found in orbital and ocular diseases, including orbital inflammations and neoplasms; intraocular inflammations and neoplasms; vascular diseases including systemic vascular disease (hypertension), vasculopathies, and anemia; the glaucomas; and documentable follow-up after medical and/or surgical treatment of these diseases.     

Surgical treatment and radiation therapy of frontal lobe meningiomas in 7 dogs

The cases of 7 adult dogs with generalized seizures managed by surgical excision and radiation therapy for frontal lobe meningiomas were reviewed. The neurological examination was unremarkable in 6 of the 7 dogs. Five dogs were operated on using a bilateral transfrontal sinus approach and 2 using a unilateral sinotemporal approach to the frontal lobe. One dog was euthanized 14 d after surgery; radiation therapy was initiated 3 wk after surgery in the remaining 6 dogs. Long-term follow-up consisted of neurological examination and magnetic resonance imaging (MRI) and/or computed tomography (CT) scan after radiation therapy. The mean survival time for dogs that had surgery and radiation therapy was 18 mo after surgery. Frontal lobe meningiomas have been associated with poor prognosis. However, the surgical approaches used in these cases, combined with radiation therapy, allow a survival rate for frontal lobe meningiomas similar to that for meningiomas located over the cerebral convexities.     

FAT NECROSIS SIMULATING RECURRENT NEOPLASIA FOLLOWING EXTERNAL BEAM RADIOTHERAPY IN A DOG

A 4.5-year-old neutered male dog was diagnosed with incompletely excised well-differentiated lymphangiosarcoma in the right inguinal subcutaneous region. The mass had metastasized to the right hypogastric and medial iliac lymph nodes. Surgery followed by definitive radiation therapy was administered to the primary site and the sites of metastasis. The dog had a complete response to radiotherapy, and minimal acute side effects. Doxorubicin was administered after radiotherapy. Approximately 4 months following radiation therapy, the dog developed a mass, presumed recurrent tumor, in the original site. In a biopsy only steatitis and fibrosis were found. The mass continued to grow and conservative surgical excision was elected. Histopathologically the diagnosis was fat necrosis and steatitis, with a microscopic focus of lymphangiosarcoma. Fat necrosis is an uncommon sequelum to breast irradiation in people and also appears to be rare in animals. Fat necrosis should be considered as a differential diagnosis when recurrent tumor is suspected in a previously irradiated subcutaneous site in a dog.     

Emphysematous cystitis and bladder trigone diverticulum in a dog

A 14-month-old, male German shepherd dog was evaluated for chronic, recurrent Escherichia coli urinary tract infection. An initial diagnosis of emphysematous cystitis was made, which resolved with appropriate antibacterial therapy. The urinary tract infection, however, did not resolve and on further investigation a bladder trigone diverticulum was evident, thought to be congenital in origin. This report describes the apparent ultrasonographic and radiological changes, and surgical repair of the diverticulum, and reviews the literature with regard to both congenital bladder trigone diverticulum and emphysematous cystitis. The former has never been documented in the dog and the latter is an unusual finding in a non-diabetic dog.