A surgical approach for extensive orbital exenteration in dogs; a description of technique and its application in 4 cases.

OBJECTIVE: To describe a surgical approach for preplanned orbital exenteration. ANIMALS STUDIED: Indications included intraconal orbital mass lesions. Four dogs were included, 3 with neoplasia and one with retro bulbar nodular fasciitis. PROCEDURE: To facilitate complete removal of lesions, exenteration was performed by a new procedure for wide access. The frontalis and temporalis muscles were elevated and retracted through a single U-shaped skin incision. Zygomatic arch osteotomy was performed, followed by a 360-degree peritomy and zygomatic process osteotomy. The eyelids were divided from each other through the lateral cantus and then folded forward to expose the globe. The orbit was exenterated by blunt and sharp dissection. Osteotomies were closed with cerclage wires, soft tissues closed and the skin wound sutured in a T-shape. RESULTS: The present exenteration procedure gave excellent access to remove orbital contents flush with the optic foramen and orbital fissure. Postoperative swelling and pain were limited and healing uneventful. Two of the 3 neoplasia cases experienced tumor recurrence involving the brain at 18 and 20 months postoperatively, respectively. Both of these had optic canal or intracranial tumor extension preoperatively. Long-term complications included mild concavity of the operated side of the face. CONCLUSIONS: The present approach for preplanned exenteration offers excellent access for complete removal of orbital contents to the level of the optic foramen. Complications due to the surgical method are few and limited.

Retrobulbar malignant peripheral nerve sheath tumor in a golden retriever dog: A challenging diagnosis.

A 9-year-old golden retriever dog was diagnosed with a left retrobulbar mass. Fine-needle aspirations and incisional biopsies resulted in discordant diagnoses: myxosarcoma/myxoma or rhadomyosarcoma, respectively. Immunohistochemistry following exenteration allowed definitive diagnosis of malignant peripheral nerve sheath tumor with fibromyxomatous differentiation. Fifteen weeks after surgery, an aggressive recurrence resulted in euthanasia.

Tumeur rétrobulbaire maligne des gaines nerveuses périphériques chez un Golden Retriever : un défi diagnostique. Une masse rétrobulbaire gauche a été diagnostiquée chez une Golden Retriever de 9 ans. Des aspirations à l'aiguille fine et des biopsies incisionnelles ont établi des diagnostics discordants : un myxosarcome/myxome ou un rhabdomyosarcome, respectivement. Suite à l'exentération, l'immunohistochimie a permis un diagnostic définitif de tumeur maligne des gaines nerveuses périphériques avec différenciation fibro-myxomateuse. Quinze semaines après la chirurgie, une récidive agressive a conduit à l'euthanasie de la chienne.(Traduit par les auteurs).

Caracterização clínica e histopatológica de bulbos oculares de cães e gatos (2005-2015) / Clinical and histopathologic characterization of ocular bulbs in dogs and cats (2005-2015)

Objetivou-se realizar a caracterização clínica e histopatológica de bulbos oculares de cães e gatos, removidos cirurgicamente por indicação clínica, no período entre 2005-2015. Foram realizados 101 procedimentos de remoção do bulbo ocular, 93 enucleações (92%) e 8 exenterações (8%). Os procedimentos foram realizados em 80 cães, (79% dos casos) e em 21 gatos (21% dos casos). Os cães submetidos à intervenção cirúrgica apresentavam perfurações oculares (n=31, 39%), glaucoma (n=19, 24%), protrusão ocular (n=13, 16%), diagnósticos sugestivos de neoplasia (n=10, 12,5%) e outros (n=3, 2,97%). Dentre os gatos os diagnósticos clínicos compreenderam perfuração ocular (n=9, 49%), glaucoma (n=3, 14,2%), microftalmia (n=3, 14,2%), sugestivo de neoplasia (n=2, 9,5%), protrusão ocular (n=2, 9,5%) e outros (n=2, 9,5%). Vinte e sete amostras de bulbos oculares foram submetidas para avaliação histopatológica, sendo 23 provenientes de cães e quatro de gatos. Dentre as amostras de origem canina, sete exibiram achados histopatológicos compatíveis com glaucoma, sete perfurações oculares, seis neoplasias intraoculares, duas panoftalmites e um quadro de Phthisis bulbi. Nos bulbos oculares de gatos foram diagnosticadas duas neoplasias intraoculares, uma microftalmia e uma perfuração ocular. Constatou-se que o glaucoma secundário, as neoplasias e as perfurações oculares estão entre as principais causas de enucleação em cães, e associadas a alterações primárias como a ceratoconjuntivite seca e as uveítes. Estas afecções, diferentemente das neoplasias, podem ter êxito terapêutico mediante diagnóstico e tratamento precoces, prevenindo a cegueira e a remoção do bulbo ocular.(AU)

This study aimed to carry out the clinical and histopathologic characterization of ocular bulbs from dogs and cats, surgical removed as clinical indication between 2005-2015. Hundred-one procedures were performed, 93 enucleations (92%) and 8 exenterantions (8%). The procedures were performed on 80 dogs (79% of cases) and 21 cats (21% of cases). The dogs underwent to surgery had ocular perfuration (n=31, 39%), glaucoma (n=19, 24%), ocular protrusion (n=13, 16%), diagnosis suggestive of neoplasia (n=10, 12, 5%) and other (n=3, 2.97%). Among the clinical diagnosis cats comprise ocular perforation (n=9, 49%), glaucoma (n=3, 14.2%), microphthalmia (n=3, 14.2%), suggestive of neoplasia (n=2, 9.5%), ocular protrusion (n=2, 9.5%) and other (n=2, 9.5%). Twenty-seven samples of ocular bulbs were sent for histopathologic evaluation in Veterinary Pathology Laboratory, being 23 from dogs and four cats. Among the samples of dogs, seven exhibited histopathologic findings compatible with glaucoma, seven ocular perforations, six had intraocular neoplasias, two panoftalmites and condition of Phthisis bulbi. The ocular bulbs of cats received the diagnosis of two intraocular neoplasias, one microphthalmia and ocular perforation. It was found that the secondary glaucoma and ocular perforations are among the leading causes of enucleation in dogs, and associated with primary disorders such as keratoconjunctivitis sicca and uveitis. These disorders, unlike neoplasia, may have therapeutic success through early diagnosis and treatment, preventing blindness and removal of the eyeball.(AU)

Transpalpebral exenteration in cattle: a retrospective study of 115 cases.

OBJECTIVE: To describe the indications for exenteration and complications associated with the procedure. ANIMALS STUDIED: 115 cattle. PROCEDURES: Medical records of cattle presented for unilateral exenteration evaluated at the University of California, Davis Veterinary Medical Teaching Hospital from January 1985 through December 2015 were reviewed. RESULTS: Median (range) age at presentation for all cattle was 6 (0.2-30) years. The most prevalent (80.9%) indication for exenteration was squamous cell carcinoma (SCC). Cattle >5 years had higher odds (OR = 11.2, 95% CI, 2.8-45.8) for undergoing exenteration due to SCC compared to cattle ≤5 years. Herefords had higher odds (OR = 4.6, 95% CI, 1.5-14.6) for undergoing exenteration for SCC compared to other breeds. Holsteins had higher odds (OR = 140.7, 95% CI, 7.5-2644) for undergoing exenteration for retrobulbar lymphoma compared to other breeds. Complications following exenteration were reported in 15 cases (13.0%). The postsurgical complications were orbital abscesses (6/15), recurrence of SCC (5/15), wound dehiscence (3/15), and excessive hemorrhage (1/15). Median (range) time to occurrence of postsurgical complications was 19 (5-205) days. There was no significant association (P > 0.05) between ocular diagnosis, age, anesthetic technique or the suture pattern used to close the skin postsurgically, and occurrence of postsurgical complications. CONCLUSIONS: Early clinical diagnosis of SCC by owners and veterinarians may prevent the need for exenteration. Owners should be made aware of the possible postsurgical complications following exenteration in cattle.

Surgery of the globe and orbit.

Orbital anatomy and the indications and surgical techniques for a variety of small animal orbital/globe surgical procedures are discussed. Details of the more common orbital surgical procedures, including ocular evisceration, intrascleral prosthesis implantation, enucleation, and proptosis repair, are given. Common complications and postoperative considerations for these procedures are also discussed with an emphasis on the practical aspects.

Use of a caudal auricular axial pattern flap in three cats and one dog following orbital exenteration.

Orbital exenteration accompanied by wide eyelid excision in the cat and dog may leave a defect that cannot be closed in a primary fashion. This report describes the use of a caudal auricular axial pattern flap to effect closure following orbital exenteration in three cats and one dog. The most common complication was distal flap necrosis, which necessitated a second surgery in two patients.

Intraocular extramedullary plasmacytoma in a cat.

An 8-year-old, castrated male Domestic Short-haired cat was referred for evaluation of a possible intraocular neoplasm following previous ocular trauma. The eye was blind, and uveitis and an iridal mass were noted on examination. An enucleation was performed and the mandibular lymph node excised. Histopathologic examination revealed neoplastic proliferation of plasma cells in the iris and lymph node. No other evidence of disseminated disease was detected. This is the first case reported of an intraocular extramedullary plasmacytoma in the cat. The variation in clinical manifestations and potential association with multiple myeloma are not known at this time. Disseminated metastasis from a primary plasmacytoma of the uveal tract could also involve the bone marrow and be indistinguishable from multiple myeloma. Early enucleation, as in trauma-associated sarcomas, may be indicated to prevent metastasis. Periodic systemic evaluation for evidence of multiple myeloma should be performed.

Orbital lymphosarcoma associated with reticuloendotheliosis virus in a peafowl.

Lymphosarcoma associated with infection by avian reticuloendotheliosis virus was diagnosed in an Indian peafowl with exophthalmia and exposure keratitis. Exenteration of the orbit was complicated by a profound oculocardiac reflex and extensive hemorrhage during surgery. Orbital bleeding was controlled by direct pressure, electrocautery, topical administration of bovine thrombin, and application of sterile gelatin sponges and oxidized regenerated cellulose. A blood transfusion was also performed. In addition to describing methods of handling intraoperative complications of orbital exenteration in birds, to the authors' knowledge, this is the first report to describe an association of reticuloendotheliosis virus, which more commonly affects poultry, with lymphosarcoma in an Indian peafowl.

Orbital exenteration and placement of a prosthesis in fish.

OBJECTIVE: To develop a procedure for orbital exenteration and prosthesis placement in fish. DESIGN: Prospective study. ANIMALS: 5 cultured hybrid striped bass (Morone saxatilis x M chrysops) ranging from 30 to 50 cm in length. PROCEDURE: Exenteration was performed, using a dorsal approach in which blunt dissection was performed in the circumorbital sulcus. The orbit was then dried, and simple interrupted sutures were placed, leaving 2 suture loops within the orbit. The orbit was filled with polyvinylsiloxane, and a prosthetic glass eye was seated in the polyvinylsiloxane. RESULTS: All fish retained the prosthesis and had satisfactory cosmetic results at the end of the 8-week study period. CLINICAL IMPLICATIONS: The increase in popularity of pet fish and abundance of valuable aquarium and show fish have led to heightened awareness of piscine ocular disease. Aquarium fish are often euthanatized because of disfiguring ocular problems. The technique described here for surgical exenteration and cosmetic orbital prosthesis placement in fish may extend the captive life of public display fish.