What is NAAION

NAME: NAAION (or NAAION) or non-arteritic anterior ischemic neuropathy, is the sister disease of AAION, and forms with it the group of two AION’s. Popularly it is also called an ‘eye stroke’.

EFFECT: The effect of NAAION is a partial or full blindness in one or both eyes, often through a sudden nighttime NAAION event, where one wakes up in the morning and discovers the disturbing fact that one cannot see or see much in one eye (followed by both eyes in about 20% of cases). About 35% of NAAION patients may see a partial recovery over a few weeks or months, but most do not. The disease is still incurable.
So NAAION will impact not only one’s health.  It will also force patients (and families) to make life style changes. to change work or jobs, to close down one’s business, to handle lower income and higher costs and even to resolve or end strained stressful relationships.

Patients will especially have to act like the above to try prevent a second attack that will blind them entirely. Yes, it is a constant, so lifelong ‘sword of Damocles’ hanging over pone’s head.

Such an second NAAION event in the fellow eye that would blind one entirely, would mean a NAAION patient would become strongly dependent on the goodwill and help of others, often of many who do not understand the impact of the disease. This is foreseeable, since it is hard to imagine partial or total blindness for oneself if one is a healthy person. NAAION patients will benefit from educating their environment, so the impact of their (partial) blindness does not get trivialized or underestimated. It is major even if often quite ‘invisible’.

Often the underestimation by one’s environment and one’s physicians comes due to the medical industry not yet being capable of qualifying and quantifying the effect of NAAION on one’s ‘functional vision’. Especially the field of ophthalmology is still too much focused on identifying solely refractory issues or taking refraction related measurements not on mainly neurological issues like this (and their functional consequences). That is visible in the still dogmatically used ancient (over 160 years old) Snellen test determining visual acuity of patients with vision loss, while that is a test mainly once invented for refractory issues, and not even for all. Use of the Snellen visual acuity test (or more modern sister – the Logmar visual acuity test) trivializes what NAAION patients have and deal with. Those visual acuity tests actually misrepresent the NAAION condition for the most part since many NAAION patients can show a relatively good visual acuity test following the Snellen method (or its modernized Logmar version) and still have a terrible remaining functional vision.

Imagine also  how insulting it is to have an eye doctor do a pinhole test to establish if you are not ‘inventing’ your disease. Like most patients have nothing better to do.

Imagine how even more so disturbing it is for an NAAION patient to see his disease, his blindness trivialized, as if he is imagining:
– being exhausted already halfway the day,
– seeing only blurred images in his eye,
– having varied quality of vision through the day,
– seeing letters merge into each other, 
– making numerous typos due to insufficient distance between letters,
– bumping into persons, (car) doors, bed edges, open windows, cupboards, chairs, pets, or stumbling int objects unexpectedly put in one’s path by others,
– dropping glass and porcelain ware due to putting it in the wrong spot due to poor visual navigation,
– spilling food over one’s clothes and on the table for wrongly estimating speed and distance of one’s movement,
– losing entirely the ability to drive due to losing overview, reacting slower, lacking correct estimation of speed and distance of oneself and others, blinding glare at night and during rain, or being forced to only drive at day time an in rural quiet areas, without being able to cover great distances so long trips due to quick exhaustion from the more frequent head movements and difficulty of brain adapting to quick  and more burdensome image input changes,
– worrying about structural stress as it may trigger another attack due to teh adrenaline impacting the blood pressure,
– being constantly on and off blinded by glare both in daytime condition outside and inside as well as even going into a dark room,
–  having the sword of Damocles hang over him every minute of the day that the other eye may also go blind,
– losing access to insurance as one’s insurability is diminished since underwriters are not so much interested in heavily handicapped people with incurable diseases given that they greatly increase their risk to have to pay out claims,
– always second guessing what to eat, drink and how much and what drugs to take or not and when, whether to fly or not, whether to exercise or not and how much, whether to give up one’s stressful job or abandon other stressers to try prevent that second attack.

Imagine also what it means financially and emotionally for a NAAION patient claiming a disability benefit, when all the deciding authority uses as a standard to determine whether one qualifies is the subjective, ancient Snellen (or its newer Logmar) visual acuity test that in no way is an accurate reflection on what remains of functional vision with a NAAION patient. One then gets denied the benefit as if one is not severely handicapped, but one is if one cannot function by far like one used to. There is no functional vision test though to provide an objective decision. Again this is also a form of trivialization beyond ignoring that one is often half as productive (with one eye affected and even far less or little with two affected.

Try then as an NAAION patient feel comfortable knowing that. Or try stick your head in the sand ignoring that.

Either way, NAAION is initially an unavoidably big presence. The battle is really to reduce its importance by getting more knowledgeable and getting more acceptance and understanding as well as consideration by one’s surroundings and by oneself. That way one  can reduce its impact on one’s life and move on to being as productive and happy as is still possible within the new NAAION limitations.

NAAION never goes away, but one can work on making its effect more manageable, less dominant up to the limit of one’s capacities. It requires being creative and being much more a champion for oneself than before.

CAUSE: It is not clear why NAAION happens. The main theory and partially proven, is that it is caused by a sudden hypotensive (drop in blood pressure) event, most often at night (when blood pressure already decreases naturally) resulting in  poor perfusion, so poor blood flow  around the optic nerve head (=optic disc), which is followed by optic nerve fiber cells (axons) and retinal ganglion cells (RGC’s) that connect the optic nerve with the retina, dying off.  In the first 14 days, unless treated, usually 80% of RGC’s die off.
The acute NAAION event phase is visible as a swelling of the optic nerve head (disc edema).

No, it is absolutely NO blood clot, so no thromboembolism, no obstruction of arteries, no occlusion (technical term (neuro-)ophthalmologists and optometrists often use.

Several risk factors make NAAION more likely, such as a ‘disc-at-risk’ shown in a small cup-to-disc ratio and/or drusen (deposit of fat and protein, often seen in their ‘hard’ version with calcification) at the optic nerve head.
Other factors that increase the risk for NAAION are for example: hypertension (high blood pressure), sleep apnea, vascular and heart problems,  stress, excessive weight, certain blood pressure lowering (over the counter or prescription) medications (also certain eye drops), overexertion, dehydration, flying in non-pressurized planes, climbing/hiking at high altitudes and more. Some of these factors are entirely proven in clinical studies, some are proven and contradicted in some studies or there are researchers who do not like the methods used by their colleagues, so they are then considered debatable. Or there are even lots of anecdotal causes that really have no evidence to back up their identification as cause, except MAYBE sometimes with tiny studies of a mere couple of patients that are hard or impossible to reproduce.