Behind the eye…
Trisha Oura, DVMMarch 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:
Ultrasound
Normal
m = extraocular musclef = fat
MRI
MRI (cont.)
• FNA of retrobulbar mass:– Consistent with carcinoma and chronic
suppurative inflammation
• Plan: – anti-epileptics, steroids (reduce associated
edema), consider radiation therapy +/- chemotherapy
Retrobulbar Neoplasia
• 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)
• It’s not just cancer!– Mucocele– Abscesses– Cellulitis– FB
• ….but it usually IS cancer
Differentials for retrobulbar disease
• 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
Neoplasia (n=26)
Abscess(n=10)
Cellulitis(n=6)
Mucocele(n=4)
Other(n=4)
Echogenicity
Hypo 16 (62%) 6 (60%) 1 (17%) 1 (25%)
Hyper - - 1 (17%) -
Hetero 6 (23%) 4 (40%) - 2 (50%)
Mass effect 11 (42%) 3 (30%) - -
Cavitary lesion 2 (12%) 5 (50%) 1 (17%) 3 (75%)
Bone lesion 10 (38%) 1 (10%) - - 1
Normal 1 (4%) - 3 (50%) - 3
US findings in 50 dogs with retrobulbar disease
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
• Dogs– Adenocarcinoma– Osteosarcoma– Rhabdomyosarcoma– Fibrohistocytoma– Neurofibrosarcoma– Fibroma– Retinoblastoma
• Cats– SCC– LSA– Carcinoma– Fibrosarcoma– Osteosarcoma– Meningioma
• 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:
References
• Haak CE, MA Breshears, PA Lackner. What is your diagnosis? Retrobulbar neoplasia. 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.