An extragonadal teratoma in a female cynomolgus monkey (Macaca fascicularis).

Extragonadal teratomas have not been reported in nonhuman primates. A female cynomolgus monkey, a vehicle control in an exploratory toxicity study, was necropsied. Microscopic examination of an extragonadal mass in the animal's craniodorsal retroperitoneum revealed a teratoma. This is the first report of an extragonadal teratoma in a nonhuman primate.

Idiopathic hyperostosis of the calvaria in five young bullmastiffs.

A new calvarial hyperostotic syndrome (CHS) in young bullmastiffs is described. Calvarial hyperostotic syndrome clinically resembles canine craniomandibular osteopathy (CMO) and human infantile cortical hyperostosis (ICH), but it is unique in that there is progressive and often asymmetric skull bone involvement, and the population affected appears to be only young, male bullmastiff dogs. Characteristic radiographic findings consist of cortical thickening of the calvaria with irregular, bony proliferation over the frontal, temporal, and occipital bones. Histopathological examination shows that the trabeculae of the calvarial diploë are thickened and contiguous with a sunburst-like pattern of subperiosteal trabeculae composed of woven and lamellar bone tissue, accompanied by loose fibrovascular tissue and a variable inflammatory response comprised predominantly of neutrophils. In 80% of the cases presented, the lesion was self-limiting. The etiology remains unknown; however, traumatic, neoplastic, and degenerative conditions do not appear to be primary factors in the etiopathogenesis of the syndrome. It may be that this syndrome has a familial component, similar to that described for CMO and ICH.

Oral squamous cell carcinoma in a coyote (Canis latrans).

A 19-yr-old spayed female coyote (Canis latrans) was evaluated for an elliptical swelling of the skin beneath its right eye and an elevated mass that involved the soft and hard palate and gingivae around the upper right carnassial tooth and molars. Histopathologic analysis revealed a squamous cell carcinoma, and a postmortem examination revealed no evidence of vascular invasion or dissemination to the regional lymph nodes or viscera. This report describes the biology and progresion of an oral squamous cell carcinoma in an aged captive coyote.

Healing bone using recombinant human bone morphogenetic protein 2 and copolymer.

Middiaphyseal 2.5-cm segmental defects in the right femurs of 12 sheep were stabilized with stainless steel plates and implanted with (1) 2 mg recombinant human bone morphogenetic protein 2 and poly[D,L-(lactide-co-glycolide)] bioerodible polymer with autologous blood (n = 7), (2) 4 mg recombinant human bone morphogenetic protein 2 and poly[D,L-(lactide-co-glycolide)] and blood (n = 3), or (3) poly[D,L-(lactide-co-glycolide)] and blood only (n = 2). Bone healing was evaluated for 1 year using clinical, radiographic, gross pathologic, and histologic techniques. Union occurred in three sheep in Group 1, two in Group 2, and none in Group 3. In the animals that healed, new bone first was visible radiographically between Weeks 2 and 6 after implantation; new bone mineral content equaled that of the intact femur not surgically treated by Week 16; recanalization of the medullary cavity approached completion at Week 52; and at necropsy the surgical treated femurs were rigidly healed, the poly[D,L-(lactide-co-glycolide)] was resorbed completely, and woven and lamellar bone bridged the defect site. In two Group 1 sheep euthanized at Weeks 2 and 6, polymer particles were permeated by occasional multinucleated giant cells. Some plasma cells, lymphocytes, and neutrophils were present locally. The poly[D,L-(lactide-co-glycolide)] tended to fragment during surgical implantation. Despite these observations, the recombinant human bone morphogenetic protein 2/poly[D,L-(lactide-co-glycolide)] implant was able to heal large segmental bone defects in this demanding model.

A new animal model for maxillary sinus floor augmentation: evaluation parameters.

This study describes a novel animal model of the maxillary sinus floor augmentation procedure used to assess bone formation during 12 weeks in response to a recombinant human bone morphogenetic protein-2 (rhBMP-2)/absorbable collagen sponge (ACS) sinus implant. A buffer-ACS implant was used as a control. Animal response was monitored using computerized tomography and physical, hematologic, gross pathologic, and histologic evaluations. The rhBMP-2/ACS implants maintained a relatively constant size postsurgery and showed a time-dependent increase in mineralization. The buffer/ACS control implants failed to mineralize and were resorbed by 4 weeks. The model served effectively and without complication. Results indicate rhBMP-2/ACS implants deserve consideration as alternatives to traditional grafting procedures.

Ultrasonography of the brain and vertebral canal in dogs and cats: 15 cases (1988-1993).

Medical records of 3 cats and 12 dogs with lesions of the brain (3 cats, 2 dogs) or vertebral canal (10 dogs) that underwent intraoperative ultrasonography were reviewed. Ultrasonography was performed after craniotomy, a ventral slot procedure, or laminectomy, using a real-time sector scanner with a 7.5- or 10-MHz transducer. In the 3 cats and 2 dogs with brain lesions, cerebral masses were hyperechoic, compared with normal brain, and were easily located. In the 2 dogs, ultrasonography was necessary to localize deep-seated cerebral lesions that could not be seen following craniotomy. In 7 dogs that underwent a ventral slot procedure because of prolapse of an intervertebral disk, ultrasonography was successfully used to assess completeness of disk removal. The remaining 3 dogs underwent dorsal laminectomy because intradural enlargement of the spinal cord (1 dog) or an intradural mass (2 dogs) could be seen myelographically. In the 2 dogs with intradural masses, intraoperative ultrasonography helped to delineate the extent of the tumor. In the third dog, spinal cord swelling was seen ultrasonographically; the histologic diagnosis was spinal cord edema.

Treatment of nephroblastoma in a juvenile dog.

A 4-month-old female Bernese Mountain Dog that was examined because of abdominal distention was found to have a nephroblastoma during exploratory laparotomy. Nephrectomy was performed, but the tumor could not be completely resected. A chemotherapeutic plan for this dog was created by adapting current recommendations for treatment of people with nephroblastoma. Chemotherapy was tolerated extremely well; however, tumor progression became evident after 15 weeks of treatment, and the dog was euthanatized. Widespread metastasis was found at necropsy. Little is known about the natural behavior of this tumor in dogs.

Long-term healing of bone using recombinant human bone morphogenetic protein 2.

A 2.5-cm-long middiaphyseal plate-stabilized segmental defect in the right femora of 5 adult sheep was implanted with 1.5 mg of recombinant human bone morphogenetic protein 2 mixed with inactivated demineralized ovine bone matrix. Bone healing was evaluated for 12 months using clinical, radiographic, gross pathologic, and histologic techniques. Bone formation within the defect was first visible radiographically between Weeks 2 and 4 after surgery; bone union was apparent between Weeks 12 and 16, at which time the plates were removed. Recanalization of the medullary cavity with neocortex formation was near completion at Week 52. Bone mineral content at the defect sites equaled that of the nonsurgically treated intact femora by Week 16. Perifemoral soft tissue mineralization did not occur, and callus size was not greater than that formed with autograft. By Week 52, the sheep were not lame, and at necropsy the surgically treated femora were rigidly healed. Woven and lamellar bone bridged the defect site. An apparently normal sequence of ossification, modeling, and remodeling events had occurred. Recombinant human bone morphogenetic protein 2 mixed with a suitable carrier could provide an alternative to autograft for use in a variety of orthopaedic procedures.

A light microscopical, ultrastructural and immunohistochemical study of spindle-cell adrenocortical tumours of ferrets.

Twelve adrenocortical tumours with a variable spindle-cell component in ferrets (six spayed females, three intact females, two castrated males, and one intact male) were examined by light microscopy. One tumour with a moderate spindle-cell component was examined ultrastructurally, and three tumours were studied immunohistochemically. Light microscopy revealed a spindle-cell component in the tumours that varied from a few such cells occupying the stroma between packets of adrenocortical cells to cells in such large numbers that they formed almost the entire substance of the tumour. By light microscopy these spindle cells resembled smooth muscle cells, and the ultrastructural findings, particularly the presence of thin contractile filaments, suggested that the spindle cells were of smooth muscle origin. Immunohistochemical staining revealed that the spindle cells were negative for cytokeratins and S-100 protein but positive for smooth muscle actin. Desmin was readily demonstrated in two tumours but not in the other examined. Vimentin was variable, generally producing a small to moderate amount of reaction product.

Mucinous adenocarcinoma of the ovary as a cause of ascites in a goat.

A 6-year-old Nubian doe was evaluated because of slowly progressive abdominal enlargement of 1 month's duration. Five days prior to examination at our hospital, the doe was examined by a local veterinarian. False pregnancy was suspected, and 10 mg of prostaglandin F2 alpha was injected IM. Abdominal distention did not decrease, and the doe did not develop a vaginal discharge. An additional 10 mg of prostaglandin and 24 mg of dexamethasone were injected IM, about 80 hours after the first injection, again without any apparent effect. On arrival at our hospital, the doe was in sternal recumbency and was too weak to stand unassisted. Its abdomen was distended. The body of the uterus and part of 1 uterine horn could be examined by means of transrectal ultrasonography, both appeared normal. The doe was admitted to the hospital, but its condition worsened, and it died during the night. Postmortem examination revealed approximately 30 L of clear, pale, straw-colored fluid in the peritoneal cavity. The caudal pole of the left ovary contained an indistinct, firm, slightly raised, gray-tan mass. The final diagnosis was mucinous adenocarcinoma of the ovary metastatic to the partietal peritoneum, pericardium, and lungs. In adult female goats with bilateral abdominal distention, hydrometra associated with false pregnancy should always be considered; however, if there is no response to prostaglandin administration, distention is more likely to be a result of ascites.

Surgical treatment of hepatobiliary cystadenomas in cats: five cases (1988-1993).

Medical records of 5 cats with hepatobiliary cystadenomas treated by means of surgical excision were reviewed. All cats were examined because of lethargy or abdominal enlargement. A cystic liver mass was seen in each cat ultrasonographically. Postoperative complications did not develop, and none of the cats developed evidence of tumor recurrence. Four cats died 12 to 44 months after surgery. Two cats were euthanatized for unrelated problems, and 2 cats died suddenly 25 and 44 months after surgery; the causes of death were not determined in either case. One cat was alive and considered clinically normal on physical examination 42 months after surgery.

Retarded bone formation in GM1-gangliosidosis: a study of the infantile form and comparison with two canine models.

The development of skeletal lesions in two canine models of GM1-gangliosidosis, English springer spaniels and Portuguese water dogs, has been studied and compared to osseous abnormalities in a child with the infantile form of the disease. In the canine models, skeletal dysplasia was progressive. Lesions were noted at 2 months of age and characterized by retarded endochondral ossification and osteoporosis. Older puppies had focal cartilage necrosis within lumbar vertebral epiphyses. At the cellular level, lesions were characterized by chondrocytic hypertrohy and lysosomal accumulation of storage compounds. Our studies illustrate that the skeletal lesions in both canine models are similar to those in a child with GM1-gangliosidosis. Furthermore, we proposed that the abnormal storage of partially degraded compounds in affected chondrocytes might explain, at least in part, the retarded bone formation noted in patients with GM1-gangliosidosis.

Comparison of fibrosarcomas that developed at vaccination sites and at nonvaccination sites in cats: 239 cases (1991-1992).

Questionnaires were sent to veterinarians who had submitted a fibrosarcoma from a cat to the surgical pathology services of the veterinary schools of the University of Pennsylvania and Tufts University between Jan 1, 1991 and June 30, 1992. Questionnaire items included signalment, FeLV and feline immunodeficiency virus status, site of sarcoma, vaccination site, vaccines used, treatment, biologic behavior of the tumor, and final outcome. Data were analyzed, using Student's t-test for continuous data, chi 2 test for categoric data, and log-rank test for survival estimates. Comparing results for cats with vaccination-site (VS) tumors and nonvaccination-site (NVS) tumors, we determined that VS tumors developed in younger cats and were larger than NVS tumors. Although VS sarcomas were biologically aggressive and redeveloped more often than NVS sarcomas, metastasis was not detected, and cats with VS tumors survived longer than cats with NVS tumors. Vaccination-site sarcomas developed in cats after injection of many types of vaccines, administered singularly or in combination. Of the cats in the VS group administered a single vaccine, 37% were given rabies, 33% were given feline viral rhinotracheitis/calicivirus/panleukopenia virus, and 30% were given FeLV vaccines. Cats with VS tumors were more likely to have received FeLV vaccine and less likely to have received rabies vaccine than those with NVS tumors. Although vaccines produced by certain manufacturers were used most often in cats with VS and NVS sarcomas, it was believed that this probably represented marketing practices and brand popularity.(ABSTRACT TRUNCATED AT 250 WORDS)

Chondrosarcoma of the radius with distant metastasis in a dog.

A 9-year-old castrated male Doberman Pinscher was admitted for evaluation of lameness of the left forelimb. Radiography and examination of biopsy specimens revealed a moderately differentiated chondrosarcoma of the proximal portion of the radius. The dog was treated by local excision of the neoplasm, which involved resection of the radial head and proximal portion of the radius. Despite the large size of the dog and the weight-bearing forces exerted on the cubital joint, major problems with ambulation did not develop after surgery. Functional use of the limb returned slowly; however, substantial limb use was observed despite the development of mild degenerative changes of the joint and migration of the humeroulnar articulation. Six months after surgery, metastasis of a widely disseminated, poorly differentiated chondrosarcoma to the subcutaneous tissues and thoracic and abdominal cavities was diagnosed. Local redevelopment of the chondrosarcoma in the area of the cubital joint was not detected. Resection of the radial head and proximal portion of the radius may be considered a viable, alternative, limb-sparing technique. The biologically aggressive nature of this chondrosarcoma of the appendicular skeleton indicated that additional information was needed before a reliable prognosis could be established for this dog with this tumor type. Reports of low rates of metastasis have been based on insufficient numbers of dogs to adequately or accurately determine the long-term prognosis of dogs with chondrosarcoma of the appendicular skeleton.

Pediatric neuroimaging.

In this article, some of the common and not-so-common neuropediatric disorders were discussed. As in the full-grown animal, abnormalities of the CNS in the pediatric animal patient may be classified according to the type of insult present (eg, malformation, injury, neoplasia, inflammation, or degeneration). To recognize the imaging manifestations of such disorders, an appreciation of normal anatomy, the pathological response of nervous system tissue to insult, and the principles of image interpretation is required. These fundamentals may then be applied to any CNS disease, regardless of frequency and to any animal patient, regardless of age.

Osteomyelitis and disseminated infection caused by Corynebacterium renale in a goat.

A 1.5-year-old female goat was examined for recurrence of lameness involving the right forelimb. Radiography of the thorax and right scapulohumeral joint revealed a pathologic fracture of the supraglenoid tubercle, and circumscribed radiolucent lesions in the right third and fourth ribs, and the base of the spinous process of T3. Bone scintigraphy demonstrated additional lesions in the lumbar spine and the wings of the ilium. At necropsy, disseminated infection and hematogenous osteomyelitis were diagnosed. Corynebacterium renale was cultured from the rib lesions. In food animals, osteomyelitis usually develops secondary to traumatic wounds, and members of the genus Actinomyces are frequently incriminated as the causative organism. This case is unusual because the osteomyelitis was unrelated to a traumatic wound, and the gross and microscopic lesions were reminiscent of caseous lymphadenitis, an infection caused by C pseudotuberculosis.

Controlled tissue expansion in the distal extremities of dogs.

Controlled tissue expansion using a 100 cc rectangular silicone elastomer expander was performed in the mid-antebrachium and mid-crus of eight adult mixed-breed dogs. Two expander inflation schedules were followed. Group 1 dogs (n = 4) underwent expander inflation using 10 cc sterile saline every other day, and group 2 dogs (n = 4) underwent expander inflation using 15 cc sterile saline every other day until the nominal volume (100 cc) was attained. Significant mean postexpansion increases in skin surface area of 94.1 cm2 (35.9%) and 108.9 cm2 (37.3%) were measured in the antebrachium and crus, respectively (p < .05). In a second procedure, the expanders were removed and skin flaps were developed from the redundant tissue generated during the expansion process. Single pedicle advancement flaps and transposition flaps were used to cover surgically created defects measuring 5 x 10 cm in the antebrachium and crus. Single pedicle advancement flaps consistently measured 10 x 10 cm and could be advanced to cover defects involving one third of the mid-antebrachial or mid-crural circumference. Transposition flaps were rotated up to 170 degrees and the donor site defects were easily closed under minimal or no tension. Complications included an abscess in one dog and seroma formation in four dogs. Differences in success or complication rates between group 1 dogs and group 2 dogs were not observed; an accelerated inflation schedule using 15 cc sterile saline every other day was recommended.