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Sudden permanent incremental reductions in brightness levels
Hello,
For many years now, I have sudden events every few months to every few years that suddenly reduce my brightness levels in both eyes at the same time by a small amount, while leaving everything else (visual acuity, colour perception, etc) working normally without any change. The pattern is that there is one distinct event every few years, followed by a series of smaller events in the following months before it stabilises again.
This new brightness level becomes the new permanent brightness level. There is also strong tiredness for a few days after an event. There is no change in my behaviour or activity/eating patterns before one of these event sequences start.
Hospital eye clinics and neurology doctors cannot find a reason. There is nothing obvious in the eyes themselves. VEP tests have not revealed anything. I am due for another MRI but previous MRIs have not found anything.
This is also noticable in various other ways, such as going outside while pupils are dilated, which used to be painful. However, due to the reduction in brightness levels, that has not been true for years.
Has anyone ever seen anything like this before, with just a sudden change in brightness levels in both eyes at the same time (usually overnight while sleeping) without any other detectable changes ? If so, was there a confirmed diagnosis made ?
I am looking for viable suggestions I can run past the doctors in case there is something rare they have not considered, so thanks for any hints or suggestions.
Given the lack of noticable structural changes, I am now wondering if this might be some brain processing or neurotransmitter problem, but I am mostly healthy in other respects, and do things like long day walks (10-15 miles) several times a month without any problems.
Thank you for any ideas you may have. There is clearly something very unusual going on and my own research has not turned up anything so far.
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@jimw9 Posterior capsule opacification (PCO) is the most common complication of cataract surgery.
Posterior capsule opacification (PCO) is the most common complication of cataract surgery.
@riy cataract
This also happens to me overnight and I lose vision. This happened in right eye and now in left eye. I can only see part of a sentence and things are not bright . Glare is bad also. Any sun glasses anyone had found to make things brighter and what color lens? I find blue light glasses help me to read a little better . I am showing optic nerve damage and being treated again for GCA. Prayers for healing and comfort for all.
If you research : Diagnoses to ask Doctors to explore:
1. The "Broken Volume Knob" (Thalamic Gain Control)
The brain has a central relay station called the Lateral Geniculate Nucleus (LGN). Its job is to act like a volume knob for light. It decides how much "brightness" reaches the visual cortex.
The Theory: In these cases, the "software" that calibrates the LGN over-adjusts during sleep. When the person wakes up, the brain has permanently set the "gain" lower.
The "Stepwise" Nature: Because this is a regulation failure, it doesn't "leak" vision away slowly. Instead, it "snaps" to a new, lower setting—often during the transition from sleep to wakefulness—and remains there.
2. Autoimmune Retinopathy (AIR)
This is the "stealth" cause of permanent dimming. It is a condition where antibodies attack the proteins that help the retina process light.
The Trap: AIR is notorious for leaving the retina looking perfectly normal on a standard exam.
The Symptom: It often progresses in "stair-steps." A person will have a "bout" of activity where they lose a level of brightness, then it plateaus for years, then another "bout" occurs.
The Test: A standard eye exam won't catch this. It requires a Full-Field ERG (which tests the electrical "firing" of the retina) and an Anti-retinal Antibody panel.
There are more theories on what is happening with your situation but this is a start.
Like the dim world we with macular degeneration live in - there is no cure. I use yellow cocoons ( brand name) wrap arounds to drive with to brighten things up and make it clearer. Modern medicine has no cure for many diseases. You should be seen at a major eye hospital like Wilmer, Wills or Bascom Palmer. Ask the Dr if an ERG can be done-
⚡ What an ERG does
Electroretinogram
• measures the electrical response of the retina
• tells you:
• are the photoreceptors firing normally?
• is the signal strong or weak?
Ordinary teaching hospitals don't have this testing equipment. There is another test a Doctor can perform called VEP Visual Evoked Potential, you can google this.
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@sjs1, have you had issues with brightness and eye surgery as well?
@sueinmn Yes. The current suspect is maybe some form of brain processing problem. Maybe triggered incremently by something unknown happening overnight. The problem is that there's nothing here that they can think of to try measuring as all the usual tests are negative.
They are currently trying an experiment with epilepsy drugs in an off-label role but it is currently not having any benefit. Before anyone else thinks about this approach, I very strongly recommend discussions with medical professionals and research undertaken by yourself about whether this if worthwhile trying for you and the risks involved.
These are some serious drugs and require a strongly disciplined approach to taking them. You will need a buildup regime to get your body used to them and you really should maintain a medicine dairy. Once started, you CANNOT casually stop and restart taking them at will. You need to build up your own understanding of this so I will not be offering more advice on this - do your own research and go to your medical professionals to discuss this further if this interests you.