#diopters and myopia are not words people with good vision hear

[socialpermadeath]

Another Star Trek headcanon (that is partially canon). Humans have cured basic vision impairments. Myopia, presbyopia, and astigmatism are all corrected shortly after birth as standard procedure for human children. Optometrists will only see a patient when they're born or when there's an injury that requires their oversight to treat.

This isn't the case for every other species though. Certain species just don't have the kind of benign vision impairments that humans have. Ferengi for instance all have close to perfect vision save for a few very rare cases. Humans are unique in that such a large number of them are born virtually blind and need corrective surgery to survive and as a result, they've perfected preventative surgical treatments.

This does however mean that when a federation doctor encounters a species who's still using corrective lenses for refractive errors, they aren't entirely sure what to do. Cardassians for instance have a relatively small number of visually impaired people and can't utilize the federation's surgical technology because it can increase their already problematic light sensitivity. So Garak, being stuck on DS9 is in the awkward position of not being able to get a hold of contact lens solution or see someone who's specialized in testing for and crafting the appropriate lenses for his vision and has to rely on Julian's clumsy attempts at Cardassian optometry.

[blindprof]

It’s Complicated

When people first hear me say that I am blind or severely visually impaired (B/VI), the most common reaction is surprise…followed by sympathy…followed most often by awkward silence. This is totally understandable. Unless you are regularly interacting with differently abled people, disabilities are uncomfortable. I feel uncomfortable and awkward around people who live with other forms of disability.

Heck, I’m still awkward around other people who are B/VI. And even this is understandable. Because each person is unique. Each manifestation of visual impairment is unique. Each path to and with B/VI is unique. Each person has unique life experiences, coping mechanisms, support networks, etc. We are all strangers in a strange land. I’ll have other posts dedicated to the whack-a-doo personal and social psychology of B/VI. For now, the focus remains on the physical, or rather the perceptual.

The second reaction is usually a question: “How bad is it” or “What do you see?” And my answer is “It’s complicated.”

In my first post, I laid out some more technical details: I have a visual field that is less that 10 degrees, night blindness, color blindness, uncorrectable myopia, light sensitivity, etc. But it’s not apparent how these details really affect what I see and how that impacts what I can do. This post will go into greater detail into what and how I see. Later posts will focus on how I (try to, with varying levels of success, stupidity, and hilarity) cope with these limitations.

It probably makes sense to start with my visual field, as this is the aspect of my vision that “qualifies” me as legally blind. However, before getting to that, we really need a basic understanding of how humans see. Don’t worry, I’ll keep it short and simple.

It may be easiest to compare the eye to a modern digital camera. A camera lens gathers and focuses light; it also constrains the amount of light passing through by altering the size of a mechanical aperture. In the human eye, these functions are performed by the lens and the pupil, respectively. In a digital camera, the lens focus light onto a CCD or CMOS sensor, which is a dense grid of light sensitive “pixels,” each generating a small electrical charge proportional to how much light (within a certain wavelength) is hitting it. The human retina is the biological, electrochemical equivalent. Finally, a digital camera has wires that transport these electrical signals to a computer, which then interprets the signals to create a digital image. Here, the human analogues are the optic nerve and the visual cortex within the brain.

As I noted in my first post, I have Retinitis Pigmentosa (RP), which primarily impacts my retina. Due to the wonders of genetics and epigenetics, other parts are impacted. But for now, I’ll focus on the retina. Characteristically, people with RP find that their retinal “pixels”—millions of light-sensitive “rod” and “cone” structures, as well as protective retinal pigment epithelial (RPE) cells from which the disease gets its name—stop functioning from the outside in. We don’t know the exact cause, nor is there yet any proven way to slow, much less reverse the process.

Of course, this is a biological process that is unique to each individual. For me, it has progressed relatively slowly from childhood. I can recall early symptoms as far back as age 6. I’ll have a separate post at some point talking about progression. But it is notable the process is neither steady nor predictable. I’ll have periods of relative stability followed by periods of perceptible loss. It’s rarely like a light switch, but rather more like a dimmer. Each area of loss will appear darker with less usable information until it is just “clicked off” by the brain, presumably redirecting its limited processing resources to doing something other than trying to interpret shotty data from dying cells. For me, the progression has also been very spotty—for example, I retained some usable vision in the extremes of my left-right periphery until just a couple years ago, despite progressively losing most of my peripheral vision between there and my center.

The result today is that I have very little of my retina remaining that pretends to function “normally.” I can detect very high contrast light vs. dark in some of my periphery, but nothing there that you would qualify as usable sight. My central vision is still somewhat functional, but has been fading rapidly of late. As I said, it’s spotty, but on average in good light I have maybe 10-15 degrees total horizontal vision and less than 10 vertical. And much of that is probably equivalent to what most would consider to be peripheral vision. To help better “feel” what this means, here are a few examples of how this manifests itself in my day-to-day life.

When I’m sitting across a table from you, I can see your face but not your hands. If I’m not socially distant, I might be able to see your eyes or your mouth, but not both at the same time. I often creep people out during a conversation because I’m constantly losing eye contact and moving my eyes to different parts of their body. I promise, I’m not “undressing you with my eyes”—people talk with their entire bodies, and I’m simply trying to catch as many visual cues as possible.

When watching TV from 10 feet away, I can “see” my entire 55-inch screen. But less than a quarter of that is in my central vision. I have to move my eyes to see detail or read signs or captions. Sports and fast action scenes are difficult to catch. A fast action, dark scene with subtitles…oy…the Battle of Winterfell may as well have been a BBC Radio broadcast.

I can read, though usually only slowly and for short periods, especially if it is paper and ink. I see only a few words at a time, so my eyes have to constantly move. This causes a lot of eye strain, and I have trouble keeping both eyes properly oriented and occasionally have periods where one eye twitches uncontrollably—obviously I’m channeling my inner Mad-Eye Moody.

And of course, navigating unfamiliar or unpredictable environments is very difficult. I navigate by moving from waypoint to waypoint, and if I don’t know the waypoints or if things jump in my way, well, bad things happen. Or maybe funny things.

More on all of these and their many repercussions in future posts.

People ask, “What do you ‘see’ in the places where you have no vision? Is it blackness? Emptiness? Blurry?” Again, it’s complicated, but for the most part, my brain has just removed those areas from its visual processing “algorithm.” So, I see the same thing that you see when something is beyond your peripheral vision…just nothing. There are long periods of adjustment as I lose sight—kind of like losing a limb and still expecting it to be there. But eventually it’s just not a part of the picture that my brain paints of the world around me.

Unfortunately, that’s not all. Night blindness is often the first detected symptom for folks with RP. What is left of my retina doesn’t detect light well, so I need much more of it. The result is that I’m totally blind in low-light situations. I need direct light to see any kind of detail. I carry a flashlight everywhere I go and use it regularly day and night.

So, I need bright light. But it is also my nemesis. My eyes compensate like one would with a digital camera…by cranking open the aperture (pupil) and turning up the gain on the sensor. This does allow me to function semi-normally in certain situations. But it also results in severe light sensitivity. As with a camera, the wider pupil also results in loss of detail, and bright light can almost entirely wash any other visual information. To make matters even worse, although my pupils do function, they are VERY slow to adjust.

The results of all of that are varied. I’ll post more details in the future. But for example, I am no longer able to read a computer screen for any length of time without inverted colors. It’s like trying to read while staring at headlights. I truly need dark mode on all of my devices. Also, changing lighting conditions are challenging, especially when they are extreme. When I come in from outside, my eyes can take many minutes to adjust. And bright light sources like sunny windows in otherwise moderately lit environments can really cause havoc.

Finally, a common comorbidity with RP are cataracts, which cause hardening and blurring of the lens. Of course, this one hit me, as well. A number of years ago, I had cataract surgery. It was great. I was the youngest patient in the surgery center by like 30 years. The process involves using a magic wand to dissolve your natural lens and replacing it with a plastic one. This gets rid of the blurring, but entirely removes the ability to focus. As a bonus, I did go from needing coke bottle glasses to just needing a couple of diopters of correction. But this further complicates reading, and means I’m constantly donning and doffing my specs or having to look below them to read. Minor in the big scheme of things, but it does make me look and feel like a damn old fart.

Okay, if you made it this far, you deserve to be let off the hook for now. There’s more like the fact that my corneas—the eyes’ (usually) clear “lens caps”—now seem to cause my sight to remain blurry for the first couple of hours of each day. Or that the eye strain can sometimes get so physically painful that I have to close my eyes for long periods during the day. But this is a mostly complete and accurate snapshot of what I’m currently living with physically.

I guess I didn’t present too many funny or uplifting or forward-looking things in here. Truth is, you kind of have to muddle along with me through these sewers to eventually find the humor and hope in all of this. Because it’s complicated. But I’ll get there if you’re patient.