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.