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A halo is a circle of diffuse light that forms around a light source, such as light from a streetlight or car. They can appear at night in very dark environments with bright light sources. 

Sometimes we can witness halos of light in the campor visual due to certain eye conditions or pathologies, such as Cataracts. Knowing the cause of halos is essential to determine the most appropriate treatment for this symptom. 

En Área Oftalmológica Avanzada We explain what halos are and why they appear in our vision.  


What are halos?

Halos are circles of diffuse light that form around a light source, such as streetlights or car headlights. 

You may have noticed these halos in car lights at night. This occurs because they form in dark environments with bright lighting. 

Seeing halos of light is quite normal and temporary. Sometimes it can happen that they appear as a result of an eye condition, such as Cataracts or after eye surgery. 

Causes of halos

Light halos can be caused by different factors, the most common are: 

  • Falls: the crystalline of the eye becomes cloudy due to the natural aging of the human body. When it ceases to be transparent, a cataract forms, causing blurred vision. Halos of light are very common in people with this pathology.
  • Ametropia: when light does not focus correctly on the retina ametropia occurs, which must be corrected with glasses, contact lenses or refractive surgery. Among the most common is the myopiaBlurred long-distance vision farsightedness, blurred vision at close range and the astigmatism, distorted vision at any distance. People with these visual defects often see halos of light in dark environments or when driving at night. 
  • Alterations in the cornea: the cornea It is the main lens of the visual system and its shape and curvature are essential for light to be projected correctly on the retina. Some pathologies, such as keratoconus, can cause halos. 
  • Eye surgeries: some surgeries can temporarily cause halos postoperatively. In these cases, they disappear on their own progressively. The LASIK surgery and the placement of multifocal intraocular lens are some of the eye surgeries that can cause them. 
  • Environmental conditions: Driving at dusk, looking at surfaces that reflect light, and camera flashes can cause halos that last a few seconds.

How to cure them?

The treatment of halos depends exclusively on their cause. When it is a minimal symptom that occurs only in certain situations, it is enough to prescribe polarized glasses to the patient to reduce this phenomenon.

All the ametropias they should be treated with corrective glasses and it is important to always use them when driving at night. You can also opt for corrective surgery to permanently treat refractive errors. 

Cataracts are corrected through surgery. It is important to note that many times the lens that replaces the crystalline lens can cause halos during the first months after the operation.

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Sometimes we can witness halos of light in the campor visual due to certain eye conditions or pathologies, such as cataracts.
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Área Oftalmológica Avanzada
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Halos of light
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