The primary function of the eye is to collect light from the environment and transport it to the brain through the nerves from where an image is formed. Due to infections, injuries, or an underlying medical condition, vision can be affected. Vision loss is prevalent, especially in older age. The vision loss could be temporary, permanent, partial, blurry, cloudy, or complete.
In some instances, the side or peripheral vision can be lost, and only the objects placed in front of the eyes can be seen. This condition is known as tunnel vision or peripheral vision loss. The causative factors are found to be the underlying medical condition. It can be temporary or permanent depending upon the causative factor.
This article will discuss the causes, symptoms, and management of the tunnel vision condition.
What Are the Possible Causes of Tunnel Vision?
The underlying medical conditions causing tunnel vision are,
Retinitis pigmentosa is an inherited disorder characterized by the gradual loss of vision. It always begins with the loss of vision at night.
The retina is the innermost layer of the eye responsible for absorbing light and transferring it to the brain through the nerve fibers and image formation for vision. The retinal layer is made up of rods and cones. Rods are found in the outer layer, and cones are located in the central part. Rods work for dim light, and cones are active for color vision. Retinitis pigmentosa affects the rods first and causes loss of vision at night and peripheral vision. Later it spreads to the cones, thereby affecting the central vision.
Ophthalmoscopy, electroretinogram (this test enables an assessment of the electrical response of rods and cones), and genetic tests will be done in addition to a physical examination to diagnose the condition and severity.
Treatment - Doctors will prescribe Acetazolamide to ease the swelling of the retinal layer. Vitamin A compounds will be prescribed to reduce retinitis pigmentosa gradually. In severe retinitis pigmentosa, the doctor suggests the patient to undergo a retinal implant to restore vision. Sunglasses should be worn every time when going out in the sun, as ultraviolet radiation exposure will influence vision loss.
When the blood flow to the brain is interrupted, the brain cells will die in some time because of reduced oxygen supply to the brain tissues, causing a stroke. It is a severe condition and needs immediate care to prevent further complications like brain damage.
The symptoms of stroke include:
Vision loss, in most cases, is permanent.
Obesity, inadequate physical activity, high blood and sugar levels, alcohol consumption, smoking cigarettes, and heart conditions like heart failure and heart attack are all primary risk factors for stroke.
There are two types of stroke - ischemic and hemorrhagic. Ischemic stroke occurs when the blood flow to the brain is interrupted. Hemorrhagic stroke occurs when the blood vessel of the brain ruptures and leaks.
Echocardiogram, computed tomography (CT) scan, magnetic resonance imaging (MRI), ultrasound, and angiogram are the most preferred diagnostic measures.
a) In case of ischemic stroke, intravenous medication of tissue plasminogen activator will be started. Endovascular therapy and angioplasty are the most preferred management methods.
b) In case of hemorrhagic stroke, stereotactic radiosurgery and surgical clipping are done.
People with high and uncontrolled sugar levels are prone to develop diabetic retinopathy. This is because the retinal layer of the eye contains blood vessels that will get damaged due to the high sugar levels resulting in the swelling and leakage of blood vessels. Even new blood vessels tend to form over the retinal layer obstructing vision. This condition causes vision loss, blurry vision, or peripheral vision loss.
Controlling the blood sugar and pressure levels is mandatory to regain the vision. In addition, the doctor will suggest taking a nutritious diet and maintaining the sugar and pressure levels.
As a person ages, the vitreous body (gel) present between the retina and lens will become fluid and cause the retina to detach, resulting in a retinal tear, which will eventually get detached completely, which is known as retinal detachment.
The symptoms of a retinal detachment are:
Pneumatic retinopexy involves injecting air into the eye to position the detached retina onto the wall of the eye.
The swelling of the eye damages the optic nerve, which is responsible for transmitting the signal from the retinal layer to the brain to form an image. Peripheral vision loss is an essential symptom of optic neuritis. Apart from these symptoms, tunnel vision, pain, fading colors, and episodes of flashing lights are seen.
Optic neuritis is commonly associated with multiple sclerosis, neuromyelitis optica, cat-scratch fever, syphilis, sarcoidosis, measles, mumps, etc.
Intravenous steroid therapy will be initiated to quicken the vision recovery. If this does not work, plasma exchange therapy will be initiated.
Due to the high pressure of the eyes, the optic nerve will be damaged, causing glaucoma. Glaucoma is, in fact, the biggest reason behind blindness in people above the age of 60.
In advanced stages of glaucoma, tunnel vision is a classic symptom.
Eye drops containing prostaglandins (Travoprost, Tafluprost) and beta-blockers (Betaxolol, Timolol) will be prescribed. In severe cases, laser therapy will be indicated.
Migraine is a condition causing a severe headache. Migraine will show visual symptoms like tunnel vision either during the course of the migraine or at the beginning. These visual symptoms are temporary and will resolve in a few hours.
Tunnel vision is seen as a symptom in all the above-discussed conditions. Therefore, the only way to manage tunnel vision is to address the underlying condition appropriately.
Of course, peripheral vision loss or tunnel vision will significantly impact the quality of life. But finding strength and ways to correct it is the right way to look at it. Seek a doctor immediately after an early sign develops so that the ophthalmologist will help chart a treatment plan to prevent complete loss of vision.
Frequently Asked Questions