remnant of central vision to see her phone or
use an app to help her find her destination, but
not be able to safely get there without being able
to see anything outside of the restricted tunnel
she’s looking through.
I have RP and it causes blindness over time.
Most people think you are completely blind
if you are visually impaired, or that you are
a “normal,” completely sighted person. The
truth is that there are so many people who are
somewhere in between.
People in the U.S. are considered “legally blind”
if they have visual acuity of 20/200 or less and/
or a visual field of 20 degrees or less. Before
I began to learn about the broad spectrum of
visual impairment, I thought people who were
“legally blind” were completely blind. A legally
blind person can see, just not very well.
I recently spent a day at the Retina Foundation
of the Southwest in Dallas. I have a wonderful
doctor, David Birch, and I’m grateful for the
team who took care of me there. My first test of
the day determined I have 20/20 visual acuity
in both of my eyes. That’s because I have 70
percent of my cone function. Cones are the
photoreceptors, the light sensitive cells in the
retina, that provide central and color vision, and
the ability to read and recognize faces.
My second test was an advanced visual field
exam, and it was like a video game with flying
dots and a button I pushed. I learned that I
have about 40 to 50 degrees of visual field, or
peripheral vision, remaining in each eye. Most
people have around 180 degrees of peripheral
vision. However, 40 to 50 degrees looking out
100 yards is quite a bit of vision. I work hard to
scan and piece together the places I can’t see.
But when you get very close to me and reach out
to shake my hand, sneak up on my periphery, or
ask me to grab something small in a place right
in front of me, I may not see it at all.
I have around 10 percent of rod function left
in each of my eyes. Rods are photoreceptors
that provide peripheral vision and vision in
dark settings. As someone with RP loses rod
photoreceptor cells, we lose our peripheral
vision and our eyesight “tunnels in.” I have a
blind spot at the top of my visual field. I would
describe it as the area where the bill of your
baseball cap goes, and directly above it. I don’t
use this vision as much as my side and bottom
periphery, but I can definitely hit my head on
cabinets that are left open!
I also have a blind spot, known as a scotoma,
just outside my central region of vision. Again,
I move my eyes a lot to make up for the loss I
have. I do not see a “black spot” here. I would
describe the area as a blurry haze with the
colors of the missing pieces mixed into the
My particular gene mutation (rhodopsin) is
considered mild in the various mutations that
present as RP according to Dr. Birch, but the
slow, steady decline that comes with RP will
continue for me. Some people with RP have
more aggressive forms that cause serious visual
impairment in their teen years or even at birth.
If you meet or come into contact with someone
who is visually impaired, I hope you will keep
in mind that blindness is not an easy thing to
define. Every person is different. If you would
like to know what someone does or doesn’t
see, especially if you are trying to help them, I
suggest politely asking them. If you happened to
ask me, I would be more than happy to tell you.
ABOVE: Jenny Schisler with her husband
and their three daughters.