Eyes blurry, head spinning.
Well, if you had too much to drink the night before, being blurry-eyed the next morning wouldn’t exactly be a surprise. Even without any alcoholic adventures, have you experienced blurry vision for a few minutes when you wake up in the mornings and wondered why?
The thing is, our eyes are constantly producing tears, even when we’re asleep. Sometimes, tear secretions dry up on the surface of our eye when we open them again after a good seven to eight hours of sleep, causing us to experience blurry vision temporarily when we wake.
If you have dry eyes, you may be more susceptible to this situation: blurry eyed in the mornings and then vision starts clearing up as the day goes on. This is because sometimes your eyelids do not fully close while you sleep, causing the surface of your eyes to dry out further and you wake up with a sandy, gritty sensation, along with blurry vision.  The condition will improve as the day goes by when you move your eyes; as you blink, you produce more natural tears to lubricate the eyes.
Prolonged eye strain can also cause you to experience blurred vision, which really means that you have significantly overworked your eyes. It could happen if you spend hours continuously staring at your computer screen intensely with focus or if you drive for very long distances without taking breaks. It’s your body’s way of telling you it needs rest. To avoid eye strain, a good rule of thumb is to practice the 20-20-20 rule: look 20 feet away for 20 seconds, after 20 minutes of work.
Another possibility is a condition called psoriasis. Psoriasis is often accompanied by itchy, red and scaly patches on the skin and can cause a condition called uveitis, where inflammation reaches the eyes and leads to swelling and blurry vision. It can affect one or both of your eyes.
If it’s something that gets better in a few minutes, there’s no cause for concern. But if you experience blurry vision which doesn’t get better on its own, it could be a signal for more serious underlying issues.
“What is blurry vision?”
Blurred vision is one of the most common visual symptoms related to the eye that makes it difficult to see clearly or sharply. 
Whether the blurring of vision was gradual or sudden in its onset is key; slower and progressive blurry vision can be caused by long term medical conditions like diabetes while sudden blurry vision is often more alarming and a cause for concern.
“Gradual blurry vision”
If you experience your vision slowly becoming fuzzy as years go by, you can almost always chalk it up to age (presbyopia, cataract, etc) or myopia progression (time to get new prescription lenses!)
However, if it’s not due to the above reasons, it could be a condition called diabetic retinopathy. If you are diabetic, over time, your high blood sugar can cause damage to blood vessels in your retina, leading to blurry vision. Sometimes, floaters also accompany this condition. It’s important that you see your eye doctor immediately if you suspect you may be suffering from diabetes and make sure to look out for the symptoms of diabetic retinopathy.
“Sudden blurry vision – 10 possible reasons”
Conjunctivitis is caused by the infection and inflammation of the conjunctiva, a tissue filled with many tiny blood vessels that covers the white of the eye. When these blood vessels get inflamed, they turn reddish and become more visible, resulting in a pink eye.
It’s caused by the same pesky viruses that also give you the common coughs and colds. The condition is not serious and usually goes away in 1 to 2 weeks but during this time, you can experience discomfort, itchiness and blurred vision. It’s good to see your eye doctor for antibacterial or antibiotic eye drop medications to heal faster.
Warning: conjunctivitis is very contagious so keep your pink eye away from your friends and family!
2. Corneal abrasion or scarring
Think of the cornea like a protective window on your house. It helps keep out the dust and the dirt. It’s the same with your cornea – it helps prevent foreign particles from entering your eyes and into your bloodstream.
However, the cornea can become scratched over time. If infection-causing bacteria get into these scratches, it can cause a corneal abrasion which may result in permanent scarring. This in turn results in blurry vision, depending on the position of the corneal scarring on the cornea.
P.S. Contact lenses are known to be the ultimate culprit of corneal ulcers and abrasion. These lenses can trap dirt and all kinds of bacteria, causing open sores on the cornea that can also blur vision.
3, Eye infections, e.g. keratitis
Keratitis is the inflammation of the cornea, caused either by an eye trauma or a scratch to the eye which injures the cornea surface or it can be caused by bacteria, viruses, and fungi. For example, bacteria and fungi can inhabit the surface of a contact lens and contaminate the eye. The herpes virus and the bacterium which causes gonorrhoea can also cause keratitis.
Symptoms of keratitis include blurry vision, eye redness and eye pain. Those who are more at risk include frequent contact lens wearers and those who have cold sores or herpes blisters. Avoid rubbing or touching your eyes with your hands and wash your hands frequently to keep viruses at bay.
4. Hyphema (bleeding of the eye)
Hyphema is the accumulation of red blood cells within the front anterior chamber of the eyes.  When the eye receives a forceful blow, dark red blood collects in the front of the eye, between the cornea and iris. This pool of blood can cover some parts of the iris and pupil, thus affecting vision.
Another cause is a bleeding complication from an ocular surgery (such as a cataract surgery or YAG laser iridotomy).
It’s important to see your eye doctor immediately if this happens as bleeding in the eye can increase the pressure within the eyes, leading to another disease called glaucoma.
Also read: Price list for Family Health Screening in Singapore (2020)
5. Retinal detachment
Retinal detachment occurs when the retina separates from the outer layers of the eye, and is a serious event which can result in complete blindness.  The most common symptom of retinal detachment is a sudden painless blurring or loss of vision. Flashes and floaters can also occur a few days or weeks prior to this.
The thing about retinal detachment is that is can be asymptomatic initially so do go for your regular eye examinations. Once you experience flashes of light or shadowy vision, be sure to visit your eye doctor immediately to check if it is a retinal detachment. If left untreated, it can result in permanent vision loss.
6. Age-related macular degeneration (blurring of central vision)
Age-related macular degeneration (AMD) is an eye disease of the retina that usually occurs with age (above 60 years old). Blurry vision is one of the main symptoms of AMD and is one of the leading causes of blindness in the elderly. 
The condition is due to blood and other fluids leaking into the macula of the eye, often resulting in vision loss to the central 15 to 20 degrees of visual field, leading to serious visual impairment.  AMD can occur suddenly and worsen quickly, so do see your eye doctor immediately for treatment.
7. Migraine with aura
Migraines – throbbing pain in the head – is a public health problem affecting 1 in 10 people of the general population. A third of migraine patients have migraines with aura, meaning they also experience transient neurological symptoms that precede or accompany the headache, which causes them to experience sudden blurred vision. 
This condition is also known as a symptom of stroke. In addition to sudden visual impairment, it’s possible to also face difficulties in speech or higher cortical functions.  Other symptoms of migraines with aura include seeing stars, an aura of light around objects, etc.
8. Optic neuritis (inflammation of the optic nerve)
Optic neuritis is the inflammation of the optic nerve, characterised by a sudden onset of vision loss.  The optic nerve is the nerve that transmits the visual information our eye sees to the brain.
This condition is associated with autoimmune diseases, in particular, multiple sclerosis. Multiple sclerosis is a disabling disease of the brain and spinal cord, causing communication problems with your brain and the rest of the body. The permanent damage caused to the nerves – including the optic nerve – can rob one of sight.
9. Temporal arteritis (inflammation of blood vessels in the head)
Temporal arteritis is a disease in which the arteries which supply blood to the head and brain become inflamed or damaged, causing blindness.  Also known as giant cell arteritis, this condition typically affects the elderly (above 50 years old).
Symptoms of temporal arteritis include sudden loss of vision in one eye, throbbing headache in the temples, unexplainable fever, etc. If you experience these symptoms, you may want to see a rheumatologist, an expert in inflammatory diseases of blood vessels who is skilled in diagnosis of this rare illness.
A stroke can be caused by either a blood clot blocking a blood vessel from transporting blood to the brain or when a blood vessel in the brain ruptures. Strokes are known to cause blurred vision in one or both eyes and severe headache. Other symptoms include a weakness or loss of coordination in muscles, slurred speech, etc.
Our central nervous system is very much associated with vision, thus many stroke patients experience decreased visual acuity and even permanent vision loss.  Strokes can be life-threatening and should be treated immediately.
All in all, it’s definitely not normal to have sudden changes in vision. If you experience blurry vision, it could be something wrong with your cornea, macular or optic nerve and also hint at an underlying medical condition that may or may not involve the eye. As with many illnesses, early detection and treatment can be a lifesaver and prevent you from losing precious sight.
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 Menon, V., Saxena, R., Misra, R., & Phuljhele, S. (2011). Management of optic neuritis. Indian journal of ophthalmology, 59(2), 117–122. https://doi.org/10.4103/0301-4738.77020
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 Pula H., Yuen, C. A. (2017). Eyes and stroke: the visual aspects of cerebrovascular disease. Stroke and Vascular Neurology, 2:doi: 10.1136/svn-2017-000079
Jolene lives for avo toasts, yoga and is a little more OCD than she cares to admit. She never fails to start her day with morning coffee and is very partial to flat whites. She is obsessed with interiors and homeware, and is currently taking her RYT 200h yoga teacher training course as an aspiring ashtangi.
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