Amniotic Membrane Transplantation Indications Procedure Steps and Key Benefits

The cornea and ocular surface can be affected by a variety of conditions that compromise tissue integrity and its ability to heal, such as corneal ulcers, persistent ocular surface defects, burns and injuries, and certain severe inflammatory conditions. In some cases, medical treatment alone may not be sufficient to restore the integrity of the ocular surface. In such situations, an ophthalmologist may consider amniotic membrane transplantation as a therapeutic option to support tissue healing and protect the ocular surface.The amniotic membrane is a thin layer of tissue obtained from the placenta after childbirth. It is processed and preserved according to specific medical standards for use in various procedures aimed at repairing the ocular surface. The membrane has properties that may help reduce inflammation and promote epithelial healing, making it an important option for treating certain corneal and conjunctival conditions.Amniotic membrane transplantation is not limited to a single technique. The method used varies depending on the nature of the condition and the depth and size of the tissue damage. The membrane may be placed over the corneal surface, inserted into the area of the defect, or applied in multiple layers in some deeper cases. It may be secured with surgical sutures or other methods, depending on the ophthalmologist’s assessment of the patient’s condition.In this article from Dalily Medical, we will discuss amniotic membrane transplantation for the eye, including the conditions that may require the procedure, the different types and techniques of transplantation, how the procedure is performed, its main benefits, possible complications, recovery time, and the most important post-procedure instructions that should be followed.

What Is Amniotic Membrane Transplantation?

Amniotic Membrane Transplantation (AMT) is a therapeutic procedure that uses amniotic membrane tissue obtained from the human placenta to help repair the ocular surface, cornea, and conjunctiva, support tissue healing, and reduce inflammation and fibrosis in certain medical conditions.

Why Is the Amniotic Membrane Used to Treat Eye Diseases?

The amniotic membrane has biological properties that may help promote healing of the ocular surface, reduce inflammation, and limit scar formation. Therefore, it may be used in the management of certain cases of corneal ulcers, persistent corneal epithelial defects, eye injuries and burns, as well as other ocular surface disorders.

Is Amniotic Membrane Transplantation the Same as Amniotic Fluid Testing?

No. They are two completely different medical procedures.

Amniotic fluid testing is a prenatal medical test performed during pregnancy. It involves taking a sample of the fluid surrounding the fetus for specific diagnostic purposes.

In contrast, amniotic membrane transplantation is a therapeutic procedure in ophthalmology that uses the amniotic membrane tissue obtained from the placenta after childbirth to help repair the ocular surface, cornea, and conjunctiva.

Where Is the Amniotic Membrane Obtained From?

The amniotic membrane is obtained from the placenta after childbirth. Donors undergo the necessary medical screening to ensure tissue safety and reduce the risk of infection transmission. After collection, the membrane is processed, prepared, and preserved according to approved medical standards and protocols at tissue banks.

What Conditions May Require Amniotic Membrane Transplantation?

An ophthalmologist may recommend amniotic membrane transplantation in certain conditions where the ocular surface has difficulty healing naturally. Some of the most common indications include:

• Persistent or non-healing corneal ulcers, particularly when healing is delayed despite treatment.
• Persistent corneal epithelial defects that fail to heal despite appropriate treatment.
• Eye injuries and chemical or thermal burns that cause damage to the ocular surface.
• Certain cases of severe dry eye disease when accompanied by significant damage to the corneal or conjunctival surface.
• Certain cases of limbal stem cell deficiency, which can affect the cornea’s ability to regenerate.
• Certain cases of severe corneal or conjunctival inflammation that result in ocular surface damage.
• Certain cases requiring ocular surface reconstruction following surgery or after the loss of part of the epithelium.

The ophthalmologist determines whether amniotic membrane transplantation is appropriate after examining the eye and assessing the underlying cause of the problem, the depth of the damage, and the condition of the cornea and ocular surface. The procedure is not suitable for every patient or every condition.

Is Amniotic Membrane Transplantation a Treatment for Keratoconus?

Amniotic membrane transplantation is not considered a primary treatment for keratoconus. The treatment plan for keratoconus varies depending on the severity of the disease, whether it is stable or progressing, and the overall condition of the eye.

Treatment options may include prescription eyeglasses, specialized contact lenses, or corneal cross-linking to slow or prevent disease progression. In some cases, intracorneal ring segments may be considered, while corneal transplantation may be an option for advanced cases when necessary.

What Are the Types of Amniotic Membrane Transplantation?

There are several techniques for using the amniotic membrane to treat conditions affecting the ocular surface and cornea. The ophthalmologist selects the most appropriate technique based on the nature of the condition, as well as the depth and size of the damaged area. The main techniques include:

• Inlay / Graft: The amniotic membrane is placed inside the defect or damaged tissue to help support the healing process.
• Overlay / Onlay: The membrane is placed over the cornea or affected area to cover and protect it and promote healing.
• Sandwich Technique: This technique combines both inlay and overlay transplantation and may be used for certain deep defects that require more than one layer of support.
• Multilayer AMT: Multiple layers of amniotic membrane are used in some cases involving deep corneal tissue defects or significant tissue loss.

The membrane may be secured using surgical sutures or fibrin glue. In some cases, the ophthalmologist may also place a bandage contact lens over the membrane to protect it and reduce friction during the healing period.

Is Amniotic Membrane Transplantation Painful?

Amniotic membrane transplantation is usually performed under local anesthesia using anesthetic eye drops, so patients generally do not experience significant pain during the procedure.

However, some patients may experience mild burning, discomfort, or a foreign-body sensation after the procedure. Temporary light sensitivity and increased tearing may also occur. The severity of these symptoms varies depending on the condition of the eye and the type of procedure performed.

How Long Does Amniotic Membrane Transplantation Take?

The duration of amniotic membrane transplantation varies from one case to another. It depends on the nature of the eye condition, the size and location of the damaged area, the transplantation technique used, and the method of securing the membrane.

The ophthalmologist can determine the expected duration of the procedure after thoroughly examining the eye and evaluating the patient’s condition.

How Long Does Recovery Take After Amniotic Membrane Transplantation?

Recovery time varies depending on the reason for the procedure and the severity of the eye damage. Surface symptoms such as redness and discomfort may improve within several days to a few weeks, while corneal healing and stabilization of vision may take longer, particularly in cases involving deep ulcers, severe injuries, or corneal scarring.

During the recovery period, patients are advised to follow all of their ophthalmologist’s instructions, use the prescribed eye drops, avoid rubbing the eye, and protect the eye from contaminated water and dust. Regular follow-up appointments are also important to ensure that the ocular surface has healed properly and that the condition remains stable.

Does Vision Improve After Amniotic Membrane Transplantation?

Some patients may notice improved vision after amniotic membrane transplantation, particularly when reduced vision is related to damage or abnormalities of the corneal surface that can improve as healing progresses.

However, improving visual acuity is not the primary goal of amniotic membrane transplantation in every case. The main purpose of the procedure is to support ocular surface repair and promote tissue healing.

If deep corneal scars or permanent changes in the shape or structure of the cornea are present, vision may not improve as much as expected. The patient may continue to require prescription glasses, specialized contact lenses, or other treatments, depending on their condition.

Can Contact Lenses Be Worn After Amniotic Membrane Transplantation?

Some patients can resume wearing contact lenses after the ocular surface has fully healed and the condition has stabilized. However, the appropriate timing for returning to contact lens use varies from one patient to another.

The ophthalmologist determines when it is safe to resume wearing contact lenses based on the condition of the cornea, the extent of ocular surface healing, the type of contact lens used, and whether a bandage contact lens was placed after the procedure.

Can I Rub My Eye After Amniotic Membrane Transplantation?

No. Eye rubbing should be completely avoided during the recovery period. Rubbing may irritate the ocular surface, displace the membrane from its intended position, and potentially interfere with tissue healing.

If you experience persistent itching or a frequent urge to rub your eye, inform your ophthalmologist so that the underlying cause can be identified and appropriately treated instead of rubbing the eye.

Can I Shower After Amniotic Membrane Transplantation?

Patients can generally shower after the procedure, but they should take care to prevent water or soap from entering the eye directly and avoid rubbing the eye while showering.

Any additional instructions provided by the ophthalmologist should also be followed, particularly during the first few days after the procedure.

When Can I Return to Work After Amniotic Membrane Transplantation?

The time required to return to work depends on the nature of the job, the condition of the eye, and the speed of recovery.

Some patients may be able to return to office-based work within a short period, while those who work in environments involving dust or chemicals, perform physically demanding tasks, or face a higher risk of eye injury may need more time to recover fully.

When Can I Exercise After the Procedure?

Patients are generally advised to avoid sports and physical activities that could expose the eye to impact, friction, dust, or sweat during the recovery period.

Contact sports and activities involving a significant risk of direct eye injury should also be avoided until the ophthalmologist confirms that it is safe to resume them. The appropriate timing depends on the condition of the eye and the extent of ocular surface healing.

Can I Swim After Amniotic Membrane Transplantation?

It is generally recommended to avoid swimming during the early recovery period, whether in swimming pools, public pools, or natural bodies of water, to reduce the risk of exposing the eye to contaminated water or potential irritants.

What Are the Possible Complications of Amniotic Membrane Transplantation?

Amniotic membrane transplantation is used to treat several conditions affecting the ocular surface and cornea, and many patients may recover without complications. However, some temporary symptoms or complications may occur. The likelihood varies depending on the condition being treated, the transplantation technique used, and how the membrane is secured.

Possible symptoms and complications include:

• Eye redness, which may be temporary during the recovery period.
• Pain, burning, or discomfort, particularly during the first few days after the procedure.
• Increased tearing due to irritation of the ocular surface.
• Light sensitivity, which may vary in severity.
• Blurred or hazy vision, which may gradually improve as the ocular surface heals.
• A foreign-body sensation, particularly when surgical sutures are used to secure the membrane.
• Displacement or partial detachment of the amniotic membrane from its intended position.
• Eye inflammation or infection, which is uncommon when appropriate screening and sterilization procedures are followed.
• Delayed healing of the corneal or conjunctival surface, particularly in cases involving severe ocular surface damage.
• Failure to achieve the desired therapeutic outcome, which may require continued treatment or an additional procedure in some cases.

Can the Amniotic Membrane Move Out of Place?

Yes. The amniotic membrane may shift or become partially detached in some cases, particularly if the eye is rubbed or subjected to friction, or if the membrane has not been adequately secured.

To reduce the risk of membrane displacement, the ophthalmologist may secure it using surgical sutures or fibrin glue. In some cases, a bandage contact lens may also be placed over the membrane to help protect it and keep it in position during healing.

If you feel that the membrane has moved or notice any unusual changes in the eye, do not attempt to adjust or remove it yourself. Instead, consult your ophthalmologist for an evaluation.

Is the Amniotic Membrane Safe for Use in the Eye?

Amniotic membrane tissue has been used for many years in procedures aimed at reconstructing and repairing the ocular surface, cornea, and conjunctiva. It is prepared for medical use through specific procedures that include tissue screening, processing, and preservation methods designed to maintain tissue integrity and minimize the risk of infection transmission.

The level of safety depends on several factors, including the source of the membrane, donor screening procedures, tissue processing and preservation methods, and the standards followed by the tissue bank or medical facility providing the tissue.

Can the Body Reject the Amniotic Membrane?

The amniotic membrane differs from tissues used in conventional organ transplantation because it has distinct immunological properties. Therefore, immune matching between the donor and recipient is generally not required, and immunosuppressive medications are not typically needed as they are for certain types of organ transplantation.

However, this does not mean that complications are impossible. Inflammation, local reactions, or problems related to the underlying eye condition may occur. Therefore, medical follow-up after the procedure remains important to ensure proper healing of the ocular surface and maintain corneal health.

Does Amniotic Membrane Transplantation Require General Anesthesia?

In many cases of amniotic membrane transplantation and ocular surface reconstruction, the procedure can be performed under local anesthesia, usually with anesthetic eye drops, which help reduce sensation during the procedure.

However, the type of anesthesia may vary depending on the type of procedure, complexity of the condition, the patient’s overall condition, and their ability to cooperate during the procedure. The ophthalmologist, in consultation with the anesthesiologist when necessary, determines the most appropriate option for each patient.

Does the Patient Need to Use Eye Drops After Amniotic Membrane Transplantation?

The ophthalmologist will usually prescribe one or more types of eye drops after the procedure, depending on the patient’s condition. These may include antibiotic eye drops, anti-inflammatory drops, or lubricating/artificial tear drops, depending on the reason for the transplantation, the method used to secure the membrane, and the condition of the ocular surface.

Patients should follow the prescribed doses and schedules carefully and should not stop or change their treatment without consulting their ophthalmologist. They should also avoid using any additional eye drops without medical advice, particularly steroid-containing drops, as inappropriate use may lead to complications.

When Should I See an Ophthalmologist Urgently After the Procedure?

An urgent medical evaluation is recommended if any unusual or worsening symptoms develop. Important warning signs that require prompt medical attention include:

• Sudden or significant loss of vision.
• Severe or increasing eye pain.
• Severe redness or redness that continues to worsen.
• Abnormal discharge from the eye.
• Severe or sudden worsening of light sensitivity.
• A white spot or noticeable change in the appearance of the cornea.
• 明显 displacement of the amniotic membrane or bandage contact lens, if one has been used.

Some mild symptoms, such as tearing, redness, or mild discomfort, may be expected during recovery. However, worsening symptoms or the development of severe symptoms should be evaluated by an ophthalmologist promptly.

Does Amniotic Membrane Transplantation Eliminate the Need for Corneal Transplantation?

Not necessarily. Amniotic membrane transplantation is primarily intended to support ocular surface healing, repair certain defects and ulcers, and reduce inflammation. However, it cannot restore a cornea that has sustained severe damage or deep scarring in every case.

In advanced cases, or when the cornea is severely damaged and other treatments do not provide adequate functional improvement in vision, the patient may require additional surgical procedures, including corneal transplantation. The ophthalmologist determines whether corneal transplantation is necessary based on the condition of the cornea, the underlying cause of the damage, and the extent to which it affects vision.

What Conditions May Require Amniotic Membrane Transplantation?

Amniotic Membrane Transplantation (AMT) is used in ophthalmology for a range of conditions affecting the ocular surface, cornea, or conjunctiva, particularly when there is tissue damage or delayed healing and medical treatment alone is not sufficient.

The amniotic membrane has properties that may help support ocular surface regeneration, reduce inflammation, and limit scar formation and adhesions. Therefore, an ophthalmologist may recommend it as part of the treatment plan for selected cases.

Main Conditions That May Require Amniotic Membrane Transplantation

Non-healing corneal ulcers: Particularly persistent ulcers or those that do not respond adequately to appropriate treatment. The membrane may be used to cover the affected area and support the healing process.

Persistent corneal epithelial defects: When loss or damage to the corneal surface layer persists and does not heal normally despite appropriate treatment.

Certain cases of severe keratitis: The amniotic membrane may be used in selected cases after the underlying cause of inflammation has been controlled, helping to restore the corneal surface and reduce inflammation.

Chemical or thermal eye burns: The membrane may be used in certain cases to help restore the ocular surface and reduce inflammation and scar formation.

Ocular surface injuries: Particularly injuries that result in partial loss of the corneal epithelium or damage to the corneal and conjunctival tissues.

Severe keratoconjunctivitis: In selected cases associated with significant ocular surface damage, the membrane may help support tissue healing.

Certain cases of severe dry eye disease: Particularly when severe dryness causes significant damage to the corneal surface or persistent epithelial defects.

Limbal Stem Cell Deficiency (LSCD): The amniotic membrane may be used in selected cases to help restore the ocular surface, depending on the severity of the deficiency and the condition of the cornea and conjunctiva.

Symblepharon: The membrane may be used in selected cases to help reconstruct the affected tissues and reduce the likelihood of re-adhesion during healing.

Following certain eye surgeries and procedures: Amniotic membrane tissue may be used when significant loss or damage to the corneal or conjunctival surface occurs, helping to reconstruct the surface and support healing.

Certain inflammatory or immune-mediated diseases affecting the ocular surface: The membrane may be considered in selected cases that cause erosion or damage to the corneal and conjunctival surfaces, following evaluation by an ophthalmologist specializing in corneal and ocular surface disorders.

Does Every Patient With These Conditions Need Amniotic Membrane Transplantation?

Not necessarily. Having one of these conditions does not automatically mean that amniotic membrane transplantation is required. The decision depends on the underlying cause, the severity of ocular surface damage, the depth of the injury, the response to medical treatment, and the condition of the cornea and conjunctiva.

The ophthalmologist, particularly a cornea and ocular surface specialist, determines whether AMT is appropriate for each case and whether the membrane should be used alone or combined with other treatments and procedures.

How Is the Amniotic Membrane Obtained?

If referring to the amniotic membrane used in ophthalmology, it is not obtained from amniotic fluid. Instead, it is obtained from the human placenta after childbirth and undergoes several carefully controlled medical procedures before being prepared for therapeutic use.

The process of obtaining and preparing the amniotic membrane generally involves several organized steps:

Obtaining the placenta after childbirth: The placenta is obtained from a donor after delivery, following the donor’s informed consent and the applicable medical and legal requirements.

Donor screening: The donor undergoes the necessary medical and laboratory tests to ensure tissue safety and reduce the risk of transmission of infectious diseases through the donated tissue.

Separation of the amniotic membrane: The amniotic membrane is separated from the other placental tissues using appropriate techniques and under conditions that meet the required standards for maintaining tissue integrity.

Processing and preparation: The membrane undergoes processing and preparation according to approved medical protocols to make it suitable for use in procedures involving the ocular surface, cornea, and conjunctiva.

Preservation: The amniotic membrane is preserved using specialized methods for medical tissue preservation, with appropriate storage conditions designed to maintain its properties and integrity until it is used.

Use in eye treatment: After completing the required screening, processing, and preservation procedures, the amniotic membrane can be used in various ophthalmic surgeries and procedures, such as corneal and conjunctival surface reconstruction and supporting tissue healing in selected cases.

Is the Amniotic Membrane Obtained From Amniotic Fluid?

No. There is a clear difference between the amniotic membrane and amniotic fluid.

Amniotic fluid is the fluid surrounding the fetus during pregnancy, whereas the amniotic membrane is one of the membranes that forms part of the tissues surrounding the fetus and placenta.

The membrane used in ophthalmology is generally obtained from the placenta after childbirth and is then processed and preserved according to specific medical procedures.

Is the Amniotic Membrane Obtained From a Pregnant Woman for Therapeutic Use?

No. The amniotic membrane is not taken from a pregnant woman for the purpose of treating another patient. It is generally obtained from the placenta after childbirth, following the donor’s consent and completion of the required medical screening.

The tissues used for medical purposes also undergo carefully controlled procedures for screening, processing, preservation, and traceability to ensure their suitability for use and reduce the risks associated with tissue transplantation.

Amniotic Membrane Transplantation and Its Techniques

Amniotic Membrane Transplantation (AMT) is used to treat various corneal and ocular surface conditions, particularly those involving epithelial loss, persistent ulcers or defects, severe inflammation, or damage to the corneal and conjunctival tissues.

The technique used varies depending on the depth, size, and location of the defect, the degree of tissue damage, and the treatment objective. The membrane may be placed inside the defect, over the corneal surface, or in multiple layers for deeper defects. It may also be secured using surgical sutures or, in some cases, fibrin glue.

First: Types of Amniotic Membrane Transplantation According to Placement Technique

1. Amniotic Membrane Transplantation as an Inlay or Graft

This technique is known as Inlay AMT or the Graft Technique. The amniotic membrane is prepared to match the size of the affected area and is then placed inside the area where corneal tissue has been lost or is deficient.

This technique may be used in selected cases, including:

• Deep corneal ulcers.
• Persistent defects associated with corneal tissue loss.
• Certain defects extending into the deeper layers of the cornea.
• Certain cases of descemetocele or severe corneal thinning, according to the cornea specialist’s assessment.

The basic concept is to use the amniotic membrane as a biological graft within the area of tissue loss, providing structural support that may help restore the cornea and promote healing.

How is it performed?

• The eye is usually anesthetized using local anesthesia.
• The affected area is cleaned, and unhealthy tissue may be removed when necessary.
• The ophthalmologist determines the size and depth of the corneal defect.
• The amniotic membrane is prepared to fit the affected area.
• The membrane is placed inside the defect.
• It is secured using fine surgical sutures or another appropriate fixation method.
• A bandage contact lens may be used in some cases to protect the ocular surface.
• The patient is monitored regularly until the corneal surface has healed.

2. Amniotic Membrane Transplantation as an Overlay or Onlay — Patch

With the Overlay or Onlay technique, the membrane is not placed inside the area of tissue loss. Instead, it is placed over the corneal surface to cover the affected area. For this reason, it is sometimes referred to as a biological bandage.

This technique may be used in selected cases, including:

• Persistent corneal epithelial defects.
• Superficial or relatively shallow corneal ulcers.
• Corneal surface damage.
• Certain chemical or thermal eye burns.
• Certain cases of severe ocular surface inflammation.

The primary goal is to protect the corneal surface, support epithelial healing, reduce inflammation, and provide a suitable environment for tissue regeneration.

How is it performed?

The membrane is prepared so that it covers the affected area with an appropriate margin around it. It is then placed over the corneal surface and may extend to the limbal and conjunctival areas depending on the nature of the condition.

The membrane may be secured using surgical sutures or another appropriate fixation method. In some cases, a bandage contact lens may be placed over the membrane to help protect it and reduce friction caused by eyelid movement.

3. Sandwich Technique

The Sandwich AMT technique may be used in selected cases involving deep corneal defects, particularly when there is significant tissue loss in addition to damage to the corneal surface.

This technique combines the two methods described above:

• One or more layers of amniotic membrane are placed inside the defect (Inlay).
• A larger layer is then placed over the corneal surface (Overlay).

This provides internal support within the area of tissue loss while also covering the corneal surface to protect it and support epithelial healing.

This approach may be suitable for certain deep or large defects where a single surface layer does not provide sufficient structural support.

4. Multilayer Amniotic Membrane Transplantation — Multilayer AMT

In some cases involving deep loss of corneal tissue, multiple layers of amniotic membrane may be placed on top of one another within the affected area.

The use of multiple layers aims to provide additional tissue within the area of loss, helping fill the defect and support corneal healing.

This technique may be used in selected cases, including:

• Deep corneal ulcers.
• Severe corneal thinning.
• Certain cases of descemetocele.
• Selected cases where there is a risk of a small corneal perforation, according to the corneal surgeon’s assessment.

This technique is not appropriate for every patient. The choice depends on the depth of the defect, corneal thickness, condition of the surrounding tissues, and whether inflammation or infection is present.

Second: Methods of Securing the Amniotic Membrane

Amniotic membrane transplantation differs not only according to where the membrane is placed, but also according to how it is secured and maintained in position.

5. Suture Fixation

Securing the amniotic membrane using fine surgical sutures is a traditional and commonly used method in a number of cases.

After placing the membrane in the desired position, the surgeon uses fine sutures to secure it to the cornea or conjunctiva, depending on the transplantation site and the nature of the condition.

Different types of surgical sutures may be used depending on the anatomical area and technique selected by the surgeon.

Advantages of suture fixation include:

• Providing clear mechanical fixation of the membrane.
• Being suitable for cases where the membrane needs to remain in place for a longer period.
• Being useful for certain large or deep defects.
• Allowing the surgeon precise control over the position and fixation of the membrane.

Potential side effects include:

• Foreign-body sensation in the eye.
• Ocular surface irritation.
• Increased redness or tearing.
• Local inflammation around the sutures.
• The need for subsequent suture removal in some cases.

6. Fibrin Glue Fixation

In some cases, fibrin glue can be used to secure the amniotic membrane instead of sutures or to reduce the number of sutures required.

With this technique, the membrane is positioned over the desired area, and a medical adhesive is used to help secure it in place.

Fibrin glue may be beneficial in selected cases where reducing suture-related irritation is desirable. However, the choice of fixation method depends on the location and size of the defect, the transplantation technique, and the surgeon’s experience.

7. Use of a Bandage Contact Lens

The ophthalmologist may place a bandage contact lens over the amniotic membrane in some cases.

The primary purpose of this lens is not vision correction. Instead, it may help to:

• Protect the corneal surface and the amniotic membrane.
• Reduce friction caused by eyelid movement.
• Improve patient comfort.
• Provide additional protection during ocular surface healing.
• Help maintain the membrane in position in certain cases.

The ophthalmologist determines whether a bandage contact lens is necessary based on the condition of the eye and the method used to secure the membrane.

Third: Types of Amniotic Membrane According to Preservation and Processing

Amniotic membrane tissue can also differ according to how it is processed and preserved before use. Several preparation methods are available for medical applications.

8. Cryopreserved Amniotic Membrane

The amniotic membrane can be preserved by cryopreservation using specialized protocols, low temperatures, and appropriate preservation solutions.

This type is used in various procedures for treating ocular surface disorders. The characteristics of the tissue may vary depending on the processing and preservation methods and the specific product used.

9. Dehydrated / Lyophilized Amniotic Membrane

With this method, water is removed from the tissue using specialized dehydration techniques, which may include freeze-drying (lyophilization).

This approach can extend storage life and facilitate the handling, transportation, and use of the membrane according to the product’s requirements.

Various dehydrated amniotic membrane products are available, and their characteristics and methods of use may differ depending on the manufacturing and processing techniques.

10. Air-Dried Amniotic Membrane

Other methods of processing and preserving the amniotic membrane are also available, including air-drying.

The characteristics of the final membrane vary according to the processing and preservation method. Therefore, no single preservation method can be considered the best option for every case.

The choice of the most appropriate amniotic membrane depends on the patient’s condition, the intended purpose of its use, the nature of the defect, the available product, and the protocol followed by the medical center.