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Behind the eye…. Trisha Oura, DVM March 29, 2010. Peanut Seymour Acc # 131024, 131064. 8 yo FS beagle 1 week lethargy, clear nasal discharge New onset seizure Now yellow/orange nasal discharge and exopthalmos (OU) Physical exam: Exopthalmos (OD>OS), decreased retropulsion OD
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Behind the eye… Trisha Oura, DVM March 29, 2010
Peanut SeymourAcc # 131024, 131064 • 8 yo FS beagle • 1 week lethargy, clear nasal discharge • New onset seizure • Now yellow/orange nasal discharge and exopthalmos (OU) • Physical exam: • Exopthalmos (OD>OS), decreased retropulsion OD • Pain associated with OD • Slight right head tilt, mild decreased hopping RF
Diagnostics for seizure/exopthalmos • Bloodwork: normal • UA: mild proteinuria • Ophthalmology consult: decreased/painful retropulsion OD, lateral strabismus, bilateral retinal hemorrhage, cataracts OU, optical neuritis OU • Imaging: • Thoracic radiographs: mild inflammatory airway disease • Abdominal US: WNL • Ocular US: • MRI:
Normal m = extraocular muscle f = fat
FNA of retrobulbar mass: • Consistent with carcinoma and chronic suppurative inflammation • Plan: • anti-epileptics, steroids (reduce associated edema), consider radiation therapy +/- chemotherapy
RetrobulbarNeoplasia • What lives there? • Optic nerve, extraocular muscles, lacrimal gland, zygomatic salivary gland, vessels, orbital bones, fat, masticatory muscles • Adjacent structures too (dental, nasal/sinus) • Clinical signs: • Exophthalmos, conjunctival hyperemia, third eyelid protrusion, keratitis, abnormal fundic exam • Uncommon (~4% of tumors in dogs/cats) • Dogs vs. cats • Malignant, primary (D) • Malignant, metastatic or adjacent (C)
Differentials for retrobulbar disease • It’s not just cancer! • Mucocele • Abscesses • Cellulitis • FB • ….but it usually IS cancer
Diagnosis? • Image! • Skull radiographs (difficult to position/interpret) • US (good first choice: inexpensive, no anesthesia) • CT • MR • US guided FNA • Exenteration with histopathology • Thoracic radiographs to look for metastases
US findings in 50 dogs with retrobulbar disease • Visualization of 86% of lesions • Most that were not visualized = inflammatory • 26/50 = neoplasia • Median age = 9 yo • Carcinoma (16), sarcoma (6), lymphoma (2), MCT (2) • 46% = primary • Most neoplasia located medially on US
Retrospective of 23 canine cases • Possible female predilection • Mean age = 8 years • 11 different tumor types; >90% malignant • >70% = primary neoplasia • ≥50% euthanized/died as direct consequence • Grave prognosis: 3/23 survived > 3 years
Retrospective of 25 cases • No breed, sex predilection (possibly larger breeds?) • Mean age of diagnosis = 8.7y (D),12.5y (C) • ~ 50% had FNA, ~ 45% of FNAs resulted in diagnosis • Treatment: surgery, chemotherapy, radiation therapy • Mean survival: • - 10 months (D), 1 month (C) • Multiple tumor types: • Dogs • Adenocarcinoma • Osteosarcoma • Rhabdomyosarcoma • Fibrohistocytoma • Neurofibrosarcoma • Fibroma • Retinoblastoma • Cats • SCC • LSA • Carcinoma • Fibrosarcoma • Osteosarcoma • Meningioma
References • Haak CE, MA Breshears, PA Lackner. What is your diagnosis? Retrobulbarneoplasia. J Am Vet Assoc 2007;231:863-4. • Attali-Soussay K, J Jegou, B Clerc. Retrobulbar tumors in dogs and cats:25 cases. Vet Ophth 2001;4:19-27. • Kern TJ. Orbital neoplasia in 23 dogs. J Am Vet Assoc 1985;186:489-91. • Mason DR, CR Lamb, GJ McLellan. Ultrasonographic finings in 50 dogs with retrobulbar disease. J Am Anim Hosp Assoc 2001;37:557-562.