Night blindness is not a dangerous disease, but the loss of vision in low light conditions caused by the disease becomes a huge obstacle to the patient’s life. The treatment of this disease is not the same for each patient because it is carried out based on the cause of the disease. Only when the cause is identified and based on that cause, the treatment will achieve positive results.
Overview of Night Blindness
What is night blindness?
Night blindness, sometimes called night blindness, is the common name for retinal pigment degeneration. Night blindness is characterized by reduced vision, narrowing of the field of vision at night or in the dark, in places with insufficient lighting. Fundus examination can see bone-like pigment patches in the retina. The disease causes serious effects on the patient’s daily life and work.
Night blindness is a condition of reduced ability to see in low light conditions.
Causes of Night Blindness
- Eye diseases: Myopia, Glaucoma (increased intraocular pressure), cataracts, retinitis pigmentosa, Usher syndrome (genetic hearing and vision impairment), … are eye diseases that can cause night blindness in patients.
- Systemic diseases: Some other diseases in the body increase the risk of night blindness, such as diabetes, Keratoconus, …
- Medication: Glaucoma drugs can be the cause of pupil closure and cause night blindness symptoms in patients.
- Nutrition: Vitamin A plays an important role in transmitting nerve impulses and converting them into images on the retina. Therefore, vitamin A deficiency is one of the important causes of night blindness.
Symptoms of Night Blindness
What are the symptoms of night blindness?
Patients can easily recognize abnormalities in their vision with symptoms of poor vision in the dark, such as when going outside at night, when the house is dark and the lights are not on, etc. In such low-light conditions, patients are very likely to stumble and bump into objects due to reduced vision.
In addition, a very common symptom in patients with night blindness is not being able to adjust their vision in time when moving from a bright place to a dark place. Sometimes, patients may have reduced vision even in full light conditions.
Doctors often do not detect abnormalities when examining the outside of the eye, unless the patient has cataracts in the late stages of the disease. Fundus examination can detect narrowing of the retinal arteries, bone-like pigment patches in the peripheral retina, pale optic disc, or cystoid macular edema.
The field of vision (the area of vision of the eye) may gradually narrow, more seriously it can lead to tunnel vision, a condition where the field of vision is severely narrowed, the patient feels like he is looking through a tube. There may also be a symptom called blind spots, meaning that in the patient’s field of vision there are small areas that cannot be seen, if the blind spots become more and more widespread, it shows that the disease is progressing seriously.
Long-term vitamin A deficiency can cause night blindness.
Risk factors for Night Blindness
Night blindness is common in older people, as they are at high risk of cataracts.
Vitamin A deficiency is also a risk factor for the disease. Children under 3 years old or malnourished children, if not provided with enough Vitamin A in their diet, can lead to night blindness. Patients with pancreatic insufficiency are also at risk of Vitamin A deficiency due to fat malabsorption, which leads to Vitamin A not being absorbed.
Hyperglycemia in diabetic patients can cause eye complications, so it is also a risk factor for night blindness.
Preventing Night Blindness
Vitamin A plays a very important role in preventing night blindness. A diet that provides enough Vitamin A and essential minerals can help prevent night blindness. Foods that are red-orange in color such as tomatoes, carrots, pumpkins, mangoes, etc.; or dark green leafy vegetables, spinach, etc. are very rich sources of Vitamin A.
For those at risk of Vitamin A deficiency such as pregnant women, children who are not breastfed, etc., Vitamin A should be supplemented to prevent the symptoms of night blindness. Taking children to take Vitamin A regularly (according to the National Blindness Prevention Program) is extremely necessary for children to have healthy eyes.
For people with congenital or genetic night blindness:
- It is necessary to follow the doctor’s treatment to limit the progression of the disease. If there are unusual signs, see a doctor immediately. Regular check-ups to check the condition of the disease as well as changes in treatment.
- Practice adapting and moving in a state of night blindness.
- Limit driving at night to avoid endangering yourself and others.
Diagnostic measures for Night Blindness
Definitive diagnosis
- Clinical examination: The doctor will collect the patient’s symptoms, medical history, and conduct a physical examination to determine the direction of night blindness, thereby indicating some appropriate paraclinical tests to help diagnose the disease.
- Visual examination: is one of the first tests to be done when night blindness is suspected.
- Electroretinography: allows assessment of retinal degeneration conditions of the eye, including determining the type of damaged retinal cells, genetic characteristics, severity, etc. This is the most important test in diagnosing night blindness in patients who come to the clinic because of symptoms of poor vision in the dark.
- Other tests: Blood tests, basic metabolic panel tests can also be useful in diagnosing the disease.
Differential diagnosis
Night blindness needs to be differentiated from infectious, inflammatory, and retinal vascular occlusion diseases in order to provide the correct treatment for the patient. Misdiagnosis has serious consequences for the patient.
Treatments for Night Blindness
Night Blindness and Treatment
It is necessary to explain to patients with night blindness about the characteristics of the disease as well as the treatment plan, so that they can clearly understand and comply with the doctor’s treatment regimen.
Treatment of night blindness depends largely on the cause of the disease. If night blindness is a consequence of myopia, cataracts or vitamin A deficiency, the symptoms of night blindness can be overcome by treating the cause of the disease. If night blindness is congenital or related to genetics, treatment is still difficult, mainly treating the symptoms and slowing the progression of the disease.
For night blindness due to myopia: the patient’s vision can be improved by wearing glasses (eyeglasses or contact lenses), including day and night vision.
For night blindness due to cataracts: lens replacement surgery significantly improves vision as well as treats night blindness symptoms in patients with cataracts.
For night blindness due to Vitamin A deficiency: patients need to supplement Vitamin A as prescribed by the doctor, the dose of Vitamin A can be 15,000 units/day orally. However, it is necessary to strictly follow the doctor’s treatment, because Vitamin A overdose can have certain side effects.
For genetic conditions causing night blindness: Patients can only be treated symptomatically and prevent the progression of the disease. In addition, premarital counseling or screening for at-risk subjects is also very necessary. Currently, many trials such as retinal microchip implant surgery, implanting healthy stem cells into the retina are being conducted in the hope of finding a treatment method to improve retinal function in patients with night blindness.
