Infiltrative (Neoplastic) Optic Neuropathy
- Visual loss caused by cancerous infiltration of the optic nerves
- Most common cancers are lung, breast, lymphoma, leukemia
- Visual loss is often the only acute clinical manifestation
- Diagnosis is confirmed by brain MRI and/or spinal fluid examination
- Subacute monocular or binocular visual loss
- Subnormal visual acuity and visual field loss in one or both eyes
- Optic discs are normal, mildly elevated, or markedly elevated
- May be the first sign of cancer or the only sign of a relapse
- Brain MRI may show enhancement of the optic nerves or optic nerve sheaths, optic chiasm, leptomeninges, or parenchymal brain/spinal masses, but…
-
Trap: brain MRI is often normal, therefore you must move to…
- Advanced imaging modalities, including positron emission tomography (PET,) which often find the primary lesion or metastases, but even an exhaustive search can be negative
- Diagnosis is usually confirmed on lumbar puncture, but…
-
Trap: meningeal spread of cancer—especially lymphoma-- is hard to detect on lumbar puncture, as cells adhere to the arachnoid membrane, so…
-
Trap: spin-down cytology or flow cytometry may be positive only after several lumbar punctures, and sometimes never!
- Optic neuritis
- Arteritic and non-arteritic ischemic optic neuropathy
- Compressive optic neuropathy or chiasmopathy
- Radiation optic neuropathy
- Paraneoplastic optic neuropathy
- Papilledema
- Diabetic papillopathy
- If the diagnosis is reasonably secure, treat with high-dose intravenous corticosteroids (1gm/day for 3–5 days)
- Refer to a neuro-oncologist, who may offer whole brain radiation and/or systemic chemotherapy
- Visual recovery is variable
- Death from widespread cancer regrettably occurs within a short time in solid tumor metastasis; longer survival and even remission may occur in hematologic malignancies