Binasal peripheral vision loss?

I've been feeling as what I can only describe as constantly "dizzy" for four months.  When I first felt this "dizziness,"  I had thought I switched up my contact lenses, then that disorientating feeling never went away.

I recently when to the optometrist to see if my vision had changed.  My vision was the same, but when the doctor did a peripheral field vision test (which a machine that showed squiggly lines) he made and interesting discovery.  I have peripheral vision loss, mostly in the bi nasal area.  I'm not having the feeling as described as tunnel vision.  There is no piece of my vision that is black and missing.  I do, however, feel as though I have been wearing a new pair of prescription glass that I had yet to adjust to for four straight months.

My question is what is most likely to be causing this?  Do I have a serious risk of permanent vision loss or blindness?

[Michael J Kutryb, MD]

My best advice is to have a board-certified ophthalmologist in your area give you a good second opinion.  Binasal defects can be caused by glaucoma or other eye or neurologic diseases - so it's important to have this looked into.  I suggest you  have a detailed visual field test with an Octopus or Humphrey/Zeiss machine as well as a complete ophthalmologic exam.  Hopefully everything will be just fine - but you need to get it checked out.  Good Luck.

Michael Kutryb