What you should do with a case and with the proposed schemes for dealing with NAION.
- blurred inf VF while watching TV, no pain, inf arcuate on VF test
- dense hypertension and hyperlipidemia but cos takes meds for both; doesn't smoke except when drinks, etc
- what do you do for tests and Tx?
First, be sure it is NAION
Next, make sure not AION
Evaluate for risk Fx
Provide with prognostic info and balanced counsel
Consider prophylactic measures fellow eye
- BP, DM, Hyperlipid, smoking, and other implicated
- nocturnal hypotension
- do not look for prothrombotic factors
- no association shown routinely for carotid disease
- does Viagra and other PDE5 inhibitors have an association with NAION?: all patients on this drug have other associated risk factors but some studies did show reproducible association
Prognosis in fellow eye:
- Beck et al study, 1997
- 12-19% risk at 5 yrs
- corroborated with other study
- Fellow eye involvement seems to be very high in patients less than 50 yo
- lots of unproven tx from steroids, BP raising, lowering, electrical stim, apheresis, etc
- will elaborate on failed attempts
- transvitreal radial neurotomy: very problematic data in studies
- maybe vitreous adhesions from a partial post vit detachment was the problem; so tried detaching the vitreous in a group of patients; again something that didn't make any sense
- how about intravitreal triamcinolone as it has worked for different papillopathies? again, conflicting reports on this
- how could reducing surface edema get at the compartment syndrome?
- this leads to anti-VEGF to reduce edema; one study in literature to date - not enough numbers yet
Lastly, what about oral corticosteroids
- Hayreh in Graefe's 2008, at 6 mo VA improved in 69% vs 40% controls
- VF data also improved
- disc edema resolved faster
- problems with this study: control group and treatment group based on patients' choice and medical status as to whether could tolerate; not well masked by investigator
- despite the flaws, maybe some benefit? but most ophthalmologists don't believe this
- these patients likely at risk for other vascular complications such as CV disease so ASA may help prevent death from MI or stroke in these patients?