Location of Glaucoma Damage

I have been told and read that glaucoma commonly attacks the visual field from the outer periphery, then inward. How common is it to have glaucoma spots in the central vision first, and then expansion across the field?  This is a condition I appear to be suffering, altho the retina specialist is not convinced the central vision damage is glaucoma.  My other eye doctor, the glaucoma specialist, says the central vision damage might be due to the glaucoma.  

My question-How common is it for glaucoma to attack the central vision first?

Russell903

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

It is quite common and it's called "paracentral scotoma".

JCH MD

[russell903]

In order to define that the paracentral scotoma is glaucoma related, and not some other eye disorder, what test should be run?  OCT?  Visual field?  I do have difficulty with visual field testing due to a high volume of floaters and liquid/solid vitreous mix in my bad eye.  Can the shape of the optic nerve give visual indication of the paracentral scotoma?  My retina doctor has me going down a path separate from glaucoma as cause of the scotoma, and the glaucoma specialist only has said its probably due to glaucoma.  Russell903

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

By definition the best test for a paracentral scotoma is the visual field. Other helpful tests are careful optic nerve observation and OCT.  A really damaged optic nerve often gives indication of whether the VF Defect will be superior or inferior but not paracentral.

JCH MD

[russell903]

Thanks for your concise answer.  I will be getting another field test soon.

Does a scotoma act like a moving body?  Even tho mine moves with the eye (amsler grid revealed no distortions), when looking thru the scotoma, it is moving, appearing to add layers of translucent film, and eventually blurs the central view.  Is such movement common for glaucoma scotoma or can it be another cause?  Russell903  

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

No a scotoma fromglaucoma always stays in the same relative position and does not move like a "floater

JCH MD

[russell903]

How can I differentiate between a glaucoma scotoma and an epiretinal membrane?  Do they exhibit similar characterisitics?  I'm told I have the epiretinal membrane, too.  Russells903

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

There is no way for you to parse out which is which.

JCH MD

[russell903]

Thank you for your good answers.  You are a terrific resource for those of us with complex eye problems.  While being served by several ophthalmology subspecialists, it is very difficult for me to get a comprehensive answer.  Russell903  

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

You're welcome. Many of the things people want definite answers for cannot be answered definitely.
JCH MD

[russell903]

I can understand that some issues cannot be unquestionably interpreted.  Perhaps the following can help you help me 'corner' my central scotoma problem.

When I have my glaucoma eye/epiretinal membrane eye closed, I see an irregular shaped image that looks like it has a light in it.  There is quite a bit of wiggling movement in that image as observed with the closed eye.  Looks like a wiggling mosaic.  

Is that any indicator of a glaucoma scotoma or an epithelial membrane?  Seems to me that the membrane would be more likely as it is in some way attached to the retina and causing electrical response (?)
Russell903

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

Don't think you could say for sure but if press the ERM would be more likely
JCH MD