Definition

The eyeball consists of three main layers: the retina, choroid, and sclera. The retina is the innermost layer composed of light-receptive cells. The light received by the retina is processed and transmitted to the brain, enabling someone to see images. The retina receives oxygen and nutrients from the layer beneath it, which is the choroid.

Retinal detachment or ablation occurs when the retina detaches from the choroid layer that provides oxygen and nutrients. This is an emergency eye condition as it can lead to blindness. The detachment of the retina from blood vessels can cause the retinal cells to lose the necessary oxygen and nutrients. The longer the retina remains detached from blood vessels, the higher the risk of permanent blindness in the eye.

Causes

There are three types of retinal detachment:

• Rhegmatogenous, this is the most common type of retinal detachment. Rhegmatogenous retinal detachment is caused by a tear in the retina, allowing fluid within the eye to seep through the tear and fill the space between the retina and the blood vessel layer. This leak causes the retina to detach from its blood vessel layer, therefore causing blood supply impairment and decreased vision. The primary cause of rhegmatogenous retinal detachment is aging. The consistency of the vitreous humour (the gel-like fluid filling the eyeball) changes, becoming more liquid in the elderly. Due to this change in consistency, the vitreous may detach from the retinal layer, usually without causing any complications. This condition is known as posterior vitreous detachment (PVD). However, the process of vitreous detachment or PVD can also lead to tears in the retinal layer due to traction. If left untreated, vitreous fluid can pass through these tears and fill the back part of the retina, resulting in retinal detachment. 
• Tractional, this type of retinal detachment can occur if scar tissue grows on the retina. Scar tissue or fibrosis is a type of tissue that forms after an injury. The nature of scar tissue is to contract the surrounding tissue. Therefore, the presence of scar tissue on the retina causes traction on the retinal layer, leading to retinal tears. Tractional retinal detachment is commonly suffered by patients with uncontrolled diabetes or hypertension. 
• Exudative, exudative retinal detachment involves the accumulation of fluid behind the retina without a tear on the retinal surface. Exudative retinal detachment can be caused by other diseases such as macular degeneration, tumours, eye injuries, and other inflammatory diseases.

Risk Factor

Some conditions that can increase the risk of retinal detachment include:

• Age: Retinal detachment is more common in older individuals, especially those over 50 years of age
• Previous retinal detachment: Someone who has experienced retinal detachment in one eye is at a higher risk of experiencing a similar condition in the other eye
• Family history: If there is a family history of retinal detachment, the risk of developing this condition may increase
• High myopia (refractive disorder): High levels of myopia, specifically greater than -6.00 D, can elevate the risk of retinal detachment
• History of eye injury: Individuals with a history of eye injuries are at a greater risk of experiencing retinal detachment
• History of eye surgery: Having undergone eye surgery, such as cataract surgery, can increase the risk of retinal detachment
• History of other eye diseases: Certain eye diseases, like uveitis (inflammation of the middle layer of the eye), can also raise the risk of retinal detachment.

Symptoms

The symptoms of retinal detachment may include:

1. Sudden flashes of light (photopsia) in one or both eyes
2. Floating spots scattered across the vision field
3. Blurred vision
4. Decreased vision in the peripheral (side) areas
5. Sensation of a curtain closing over the vision field

Diagnosis

Your doctor can diagnose retinal detachment based on medical history and a physical examination. Some tests that may be used to diagnose retinal detachment include:

• Slit lamp or funduscopy: This tool is used to examine the back of your eye. Your doctor will look for tears in the retina and determine if there is retinal detachment
• Ultrasound: This examination uses high-frequency ultrasonic waves to visualize the position of your retina, especially if there is bleeding that makes it difficult for your doctor to see the layers of your eyeball with a slit lamp

Your doctor will examine both eyes, even if you only complain about one eye. If your doctor cannot find a tear on the first visit, they may ask you to come back in a few weeks to look for tears in your retina. If you experience additional symptoms, seek immediate medical attention.

Management

Operative intervention is the primary choice in managing retinal issues, whether it's retinal tears or retinal detachment. For the treatment of retinal tears, various techniques can be employed, including:

• Laser photocoagulation: In this surgical technique, your eye doctor will use a laser to "burn" the edges of the retinal tear. This helps the torn part of the retina reattach to the choroidal layer, preventing vitreous fluid from entering and separating the retina and choroid
• Cryopexy: After administering local anaesthesia around your eye, your doctor will use an instrument to grasp the part of your retina directly. This technique involves freezing the torn part of the retina, allowing the wound to adhere back to the eyeball wall.

For the management of retinal detachment, several techniques can be employed:

• Air injection: This procedure is known as pneumatic retinopexy. Your eye doctor will inject an air bubble or gas into your eye. The air bubble will push the detached or torn retina to reattach to the choroidal layer (vascular layer). Cryopexy is also used by your doctor to manage the torn retina. The fluid accumulated behind the retina will be absorbed by the body naturally, allowing the retina to reattach perfectly. You may need to position your head in a certain way temporarily to prevent the air bubble from moving. The air bubble will also be absorbed by the body over time
• Scleral buckling: In this procedure, your eye doctor will sew a silicone material onto the white part of your eye (sclera). The pressure from this stitched material can help the eyeball reattach to the vitreous and retina. If you have multiple tears or extensive retinal detachment, your doctor may create a scleral buckle to encircle your eye like a belt. This 'belt' will be positioned in a way that does not obstruct your vision and is typically permanent
• Fluid drainage and replacement: This procedure is called vitrectomy. Your eye doctor will replace your vitreous with air, gas, or silicone oil. This can push the retina back to adhere to the choroidal layer. However, the air or gas in the vitreous cavity will eventually be absorbed by the body. On the other hand, the use of silicone oil must be replaced after a few months. Vitrectomy is often combined with scleral buckling

After surgery, usually vision will improve over a few months. You may need a second operation to complete the therapy. 

Retinal detachment can cause a complete loss of vision, disrupting your daily activities. Here are some things you can do if you experience vision impairment:

• Use glasses: While they may not fully restore vision, they can help
• Enough lighting: It can aid you in reading more clearly
• Safe house environment: Avoid using slippery carpets, and use bright markers for sharp furniture
• Inform the nearest people around you: Let them know about your condition so they can assist you with challenging tasks
• Use technology: Audiobooks and computer screens with voice assistance can aid in reading
• Build a support system: Connect with people who have a similar condition

Complications

Operative procedures carry certain risks of complications, including:

• Infection
• Bleeding
• High eye pressure (glaucoma)
• Cataracts

While there are potential complications, surgery can improve your vision, although in some cases, more than a single operation may be necessary.

Prevention

Regular eye examinations play a crucial role in early detection of conditions that may lead to retinal detachment, such as diabetic retinopathy. Routine eye check-ups can help prevent deterioration leading to the level of retinal detachment. It is recommended to undergo eye examinations at least once a year, and possibly more frequently if you have specific risk factors, such as diabetes or high myopia. If you have diabetes and high blood pressure, maintaining normal blood sugar and blood pressure levels can help preserve the health of the blood vessels in your eyes. Additionally, use eye protection when engaging in activities that pose a risk of eye injury.

When to see a doctor?

If you experience the above symptoms, promptly consult with a doctor. Retinal detachment is an emergency condition that requires swift and precise intervention. This condition does not resolve on its own.