We see the world around us through a visual mechanism that involves complex interactions between various structures in our eyes and our brain. The process of vision begins with the light from the outside world entering the eye through the cornea, passing through the lens and finally striking the photoreceptors in the retina that is located in the back of the eye. The image of the outside world is thus formed on the retina. However, the sensation of vision has only just begun at this stage.
Upon receiving the light, the photoreceptors in the retina generate electric nerve signals that travel to the brain, where they are finally put together in a mysterious way to create the sensation of seeing. We do not normally think about this complex process while seeing the world around us clearly and sharply. However, things become disconcerting when our pictures of the outside world begin to look abnormal. Visual disturbances could be caused by a defect at any point in the complex visual pathway.
Visual disturbances can take many forms: blurred vision, cloudy vision, short-sightedness, long-sightedness, distorted vision, and even blindness. A particular type of distorted vision causes people to see a grid of straight lines as zigzag or wavy lines. This condition is also known as metamorphopsia.
Causes of wavy lines in the vision
There are two main causes of metamorphopsia: macular degeneration and ocular migraines. However, other conditions that affect the eyes may also be associated with wavy lines in the vision.
Macular degeneration refers to a progressive degeneration of the macular region located in the center of the retina. It is also known as age-related macular degeneration (AMD) because it causes a progressive loss of central vision in the elderly. Metamorphopsia or wavy lines in the vision is a characteristic feature of macular degeneration. However, it is not the only feature of AMD. Apart from metamorphopsia, patients with AMD also show the following visual disturbances:
Difficulty in adapting to changes in light intensity that occur when moving from a dark region to a bright region, and vice versa.
- Visual acuity is affected. Things look hazy or blurred rather than crisp and sharp.
- Central spot in the visual field progressively becomes blank, which makes it difficult to read, recognize faces and follow road signs.
- Contrast is decreased and the colors look dull.
- Sometimes, visual hallucinations also occur. However, these are not signs of mental illness.
There are two types of age-related macular degeneration: dry and wet. Dry AMD is characterized by yellow deposits in the macula, whereas the wet AMD is characterized by leakage of fluid from abnormally proliferating blood vessels in the retina. The exact cause of macular degeneration is not known.
When symptoms such as wavy lines in the vision first appear, it is important to first check if macular degeneration is happening. This would help in diagnosing this serious problem early enough to manage the condition properly.
Also known as retinal migraine or ophthalmic migraine, ocular migraine is characterized by a migraine headache associated with a temporary loss of vision. The loss of vision usually occurs in only one eye and lasts for 4-72 hours. The exact cause of this condition is not known. However, it is thought to result from an infarct or spasm occurring in the blood vessels of the retina.
In ocular migraines, wavy lines in the vision can occur along with other symptoms such as:
- Unusual sensitivity to light
- Flashes of light in the visual field
- Blind spots
Choroidal rupture refers to a break in the choroid coat that contains the blood vessels of the eyes. It is usually caused by blunt trauma and results in metamorphopsia.
Multifocal choroiditis refers to inflammation of multiple parts of the eye including the choroid, vitreous and the retina. The cause is not known.
Pathological myopia refers to extreme short-sightedness that is characterized by major changes in the shape of the eyes. Apart from visual disturbances, vision loss is also a common outcome of this disease.
Presumed ocular histoplasmosis syndrome
This condition is characterized by atrophy and scarring of the regions adjacent to the optic disc in the eye. It is presumed to be caused by the fungus Histoplasma capsulatum and can lead to vision loss in affected individuals.
Treatment for wavy lines in the vision
The treatment options for wavy lines in the vision vary according to the underlying cause. Unfortunately, some of the underlying causes do not have a cure at present. However, these conditions can still be managed to some extent by slowing down the progression of the underlying disease.
- There is no cure for macular degeneration, which is a frequent cause of wavy lines in the vision. However, this condition can be managed with certain treatments.
– Treatment options for dry age-related macular degeneration are very limited. In advanced cases, telescopic lenses could be implanted in patients.
– On the other hand, there are various treatment options for wet macular degeneration. A treatment with nutritional supplements such as a combination of vitamins and minerals may be prescribed to slow down the degeneration process. However, this is not effective in restoring the vision that is already lost. Patients who are smokers should speak to a doctor or a pharmacist before opting for this treatment with nutritional supplements. Several surgical options are also available for the treatment of wet macular degeneration. These include laser surgery and injection of drugs into the eyes to destroy the leaky blood vessels.
- Ocular migraines are treated by drugs such as NSAIDs, anti-epileptics and tricyclic anti-depressants. These drugs are general treatments for any types of migraine. Since the condition resolves by itself within a few hours to a few days, more specific treatments are not necessary.
- Choroidal rupture is treated with anti-VEGF drugs that prevent proliferation of blood vessels. Monoclonal antibodies against the VEGF are also used to treat both choroidal rupture and wet macular degeneration.
- Treatment of multifocal choroiditis includes corticosteroid and immunomodulatory therapies. Laser treatments have also had some moderate success.
- Glasses and refractive surgery are the main treatments for myopia.
- Treatments for presumed ocular histoplasmosis syndrome are not very effective at the moment. Despite the presumed fungal cause of this disease, anti-fungal treatments are not effective. Anti-VEGF therapy and surgery have also been tried with limited success.