Brief Blackouts and Visual Fluctuations in Your Eyes

The eyes may briefly flash black (for a few seconds), and when staring blankly, there is a sensation of fluctuating brightness?

1.
From Monday to Friday, during workdays, I often feel a momentary blackout in my vision, similar to a flickering light bulb above my head.
When it’s less intense, it feels like I’m wide awake but suddenly squinting, which is quite frightening...
This flickering sensation seems to occur less frequently on weekends.

2.
Sometimes, when I zone out without blinking, under a slightly strong light source next to my eyes, I perceive the images I see as fluctuating between bright and dark.

3.
Occasionally, I also feel like the images I’m looking at appear slightly dimmer or brighter, which genuinely scares me.
I would greatly appreciate a doctor's explanation.

Ophthalmology: I have undergone many tests, all of which returned normal results, including the retina, macula, optic nerve, and OCT.

Neurology: MRI and carotid ultrasound were also normal.

jason, 40~49 year old female. Ask Date: 2021/11/27

Dr. He Jianxian reply Ophthalmology

If you have undergone so many tests and all results are normal, there should be no need for excessive concern, as no issues are apparent.
The truly dangerous condition known as "amaurosis fugax," which is characterized by transient vision loss, typically lasts for several seconds.
During this time, vision is completely lost, as if the lights have been turned off, and it often occurs in one eye.
This can indicate a thrombosis in the retinal vessels, which is very serious and may be a precursor to a stroke.
Your symptoms do not match any similar conditions that can be identified clinically, making it difficult to provide a precise answer.
Dr.
He Jianxian, Ophthalmology Department, Nantou Hospital.

Reply Date: 2021/11/27

More Info

Understanding brief blackouts and visual fluctuations can be quite concerning, especially when they manifest as sudden darkening or fluctuations in vision. Based on your description, it seems you are experiencing a combination of visual disturbances that may be linked to various factors. Let’s break down your symptoms and explore potential underlying causes, as well as the importance of regular eye examinations.

1. Brief Blackouts or Flickering Vision: The sensation of your vision momentarily flashing black or dimming can be related to several factors. One common explanation is a phenomenon known as "visual migraines." These can occur without a headache and may cause temporary visual disturbances, including flickering lights or dark spots. Another possibility is related to the function of the retina or the optic nerve. Even if your previous examinations (OCT, retinal scans) were normal, transient issues can still arise, especially if they are related to blood flow or neural activity.

2. Fluctuating Brightness: The experience of seeing images that appear to brighten and dim, particularly under strong light sources, could be indicative of a few things. One possibility is "photophobia," which is an increased sensitivity to light. This can be exacerbated by fatigue or prolonged screen time, leading to visual fatigue. Additionally, if you are staring at a light source without blinking, your eyes may become fatigued, leading to temporary fluctuations in vision as your eyes struggle to adjust.

3. Fear of Visual Changes: It’s understandable to feel anxious when experiencing these visual changes, especially if they are accompanied by feelings of fear or discomfort. Anxiety can sometimes amplify the perception of visual disturbances, making them feel more pronounced. It’s essential to recognize that while these symptoms can be alarming, they are often benign, especially if comprehensive eye and neurological examinations have ruled out serious conditions.

4. Importance of Regular Check-Ups: Given that you have undergone extensive testing with normal results, it’s crucial to maintain regular follow-ups with your eye care provider. Sometimes, visual disturbances can be subtle and may not be detected during routine examinations. Keeping a log of your symptoms, including when they occur and any potential triggers (like stress, fatigue, or specific lighting conditions), can help your doctor better understand your situation.

5. Potential Lifestyle Factors: Consider evaluating your daily habits. Prolonged screen time, inadequate lighting, and insufficient breaks can contribute to visual fatigue. Implementing the 20-20-20 rule (every 20 minutes, look at something 20 feet away for 20 seconds) can help alleviate some strain on your eyes. Additionally, ensuring proper hydration and nutrition can support overall eye health.

6. When to Seek Further Evaluation: If your symptoms persist or worsen, or if you experience additional symptoms such as headaches, significant changes in vision, or other neurological signs, it’s essential to seek further evaluation. Sometimes, a referral to a specialist, such as a neuro-ophthalmologist, may be warranted to explore any underlying neurological issues that could be contributing to your symptoms.

In conclusion, while your symptoms may be concerning, they are often manageable and can be addressed through lifestyle adjustments and regular monitoring. It’s vital to maintain open communication with your healthcare providers and advocate for your health. Remember, your comfort and peace of mind are paramount, and understanding your symptoms is the first step toward finding effective solutions.

Similar Q&A

Understanding Brief Blackouts in Vision: Causes and Solutions

Since last year, I have occasionally experienced a brief moment of darkness in my vision (for a few seconds), similar to when a light is turned off and then quickly turned back on. I had examinations by both an ophthalmologist and a neurologist, and they reported that all test re...

Dr. He Jianxian reply Ophthalmology
Among the symptoms you mentioned, the most concerning is the sudden loss of vision. If your vision blackout lasts for several seconds to tens of seconds (rather than just a fraction of a second as you mentioned), it may raise suspicion of a thrombotic issue. If that is the case, ...

Experiencing Brief Blackouts in Vision: Eye or Neurological Issue?

Hello, doctor. Since February, I have been experiencing a strange condition. Visually, it feels like I blinked (a very brief moment of darkness lasting a fraction of a second, then immediately returning to normal vision), but I am aware that I did not actually blink. Sometimes it...

Dr. Gao Pilin reply Ophthalmology
Hello: Based on the symptoms you described and the results of the various tests conducted, this situation is indeed somewhat complex. Here are several possible considerations: 1. Vitreous Degeneration: This is a common phenomenon, especially as one ages, where the vitreous may u...

Sudden Blackout in Vision: Causes and Concerns

I would like to ask, I suddenly experienced a moment where, while looking at something, it felt like I didn't close my eyes, but suddenly a black curtain came down for less than a second, and then my eyes felt a bit uncomfortable. What could be the issue?

Dr. Gao Pilin reply Ophthalmology
Hello: Based on your symptoms, it is possible that you are experiencing amaurosis fugax, which refers to a temporary loss of vision. If this lasts only a few seconds, it may be caused by optic nerve edema or other ocular conditions. However, if the blurriness persists for a longe...

Understanding Brief Blackouts and Visual Disturbances in High Myopia

I have high myopia (left eye 650 / right eye 800) and experience floaters. Almost every weekday, I have a brief moment (0.x seconds) where I see a flash of black, about 2-3 times a day. When my eyes are still and relaxed, I feel like something in my peripheral vision is slightly ...

Dr. He Jianxian reply Ophthalmology
Hello, if all the tests are normal, I cannot provide a better explanation. Theoretically, there should be no issues. Director He Jianxian, Ophthalmology, Nantou Hospital.