Rapid deterioration of vision in left eye

[Sitakali]

I'm 27 years old and very healthy.

Last February, my glasses prescription for my left eye was -3.00 (both eyes had gotten better over the years). Now, ten months later, it's -3.75. I noticed a rapid decline in my vision in my left eye so I saw the optometrist today. She did a detailed check and said both my eyes are perfectly healthy. She gave me new contacts with a new prescription, and I could see equally well out of both eyes. As soon as the sun went down, the vision in my left eye got worse. I am already seeing a significant difference between the two eyes, wearing my brand new prescription!

I'm freaking out a bit. I Googled "rapid change in eyesight in one eye" and could only find a blog entry about Keratoconus. Anybody know what could be going on?

In addition, a couple friends have recently commented that I have poor night vision. My night vision used to be above average.

[Sitakali]

Sorry, forgot to add one thing: My left eye, with its brand new prescription, is now worse than my right eye in the daytime as well.

[Sitakali]

I have searched discussions on this site about myopia progression. They are mostly about juvenile myopia and slowing down the progression. What I want to know is what is considered a normal progression in ten months. In addition, my night vision in BOTH eyes (including the one that hasn't changed) has gotten worse very quickly as well, I take several times longer than most people to adjust to the dark, and now I'm suddenly taking a long time to adjust to bright lights.

Your explanation for why my myopia is worse in the dark doesn't explain many things. My father's prescription is closer to -5, so by your logic, his night vision should be worse than mine. Especially considering the fact that my father and I have very similar eye physiology: we are both easily corrected to better than normal vision with simple soft contact lenses; we are both nearsighted with only a slight astigmatism; we both have pupils that are about 1mm larger in diameter than the average pupil; and we both (up until now) have extremely good night vision.

[Sitakali]

My search for "myopia progression" on Google yielded many results about how to slow down myopia progression, and nothing about what a normal progression is (i.e. is a progression from -3 to -3.75 in a ten-month period considered normal or fast?).

[John C Hagan III, MD, FACS, FAAO]

When the sun goes down your pupil gets larger and you get more myopic. It's called night myopia. A small pupil helps correct some myopia. We have many discussions about myoppia progression. Right you you have simple myopia.

JCH MD

[AntonReiser]

Please google: "Myopia progression".