Optician India

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“REQUIRE NO GLUE, NO STITCHES AND STAYS IN PLACE BY ITSELF”

So… what exactly is PROKERA?

“PROKERA” is a ring-shaped biologic bandage that is applied to the surface of the eye like a big contact lens. It is made from cryopreserved amniotic membrane obtained from screened placentas. In order to combat inflammation, scarring, and vascular ingrowth on the cornea, it remains in place autonomously, protecting healing factors such as the HC-HA/PTX3 complex. It can be used by Indian opticians to improve patient comfort during fittings in cases of chronic dry eyes that do not respond to drops.

What impact can PROKERA have on repairing the surface of the eye?

The amniotic membrane of “PROKERA” reduces inflammation by reducing pro-inflammatory cytokines and neutralizing immune cell activity that affects corneal integrity. It prevents fibrosis and preserves corneal transparency and homogeneity, all of which are necessary for clear vision, while also acting as a scaffold for epithelial cell migration and adhesion. Randomized experiments have confirmed its significance in corneal nerve regeneration and increased sensitivity, resulting in long-term dry eye alleviation.

Exploring PROKERA Types

To ensure proper comfort, coverage and vision, four different types of ring designs are currently in use. 

• PROKERA Classic: Because of its thick ring design that helps to prevent the sticking of eyelids to the eyeball, this lens design is especially used in conditions like scarring.

• PROKERA Slim: This type of lens design has a thinner, low-profile ring that makes blinking and eye closure more comfortable while still giving a good healing effect.

• PROKERA Plus: Having extra layers of membrane, this lens design is used in severe eye diseases that require stronger anti-inflammatory and healing support. 

• PROKERA Clear: Designed with a central opening in the membrane, it provides simultaneous healing with better comfort and vision while the device is in place. 

The type of lens design is chosen depending upon the stage of disease and the condition of eyelids and cornea.

PROKERA's Position in Clinical Practice

Prokera is considered when conventional treatments like eye drops are not much effective and faster surface healing is needed for better visual outcomes.

Common conditions include:

• Filamentary keratitis and moderate to severe dry eye disease that remain symptomatic despite intensive therapy.

• In conditions like neurotrophic keratitis with non-healing epithelial defects or ulcers, where corneal sensation is relatively very poor.

• Persistent epithelial defects, recurrent corneal erosions and non-infectious keratitis.

• In cases like corneal ulcers and infectious keratitis that can cause scarring. These lenses help in keeping the surface close and reduce scar formation, once active infection is under control.

• Acute chemical or thermal burns and Stevens–Johnson syndrome, where early coverage helps protect the ocular surface and vision.

• Partial limbal stem cell deficiency and ocular surface reconstruction after surgeries such as pterygium removal.

Prokera can also be useful to very sick or unstable patients as it can be placed quickly at the bedside because it does not require operating theatre or sutures.

Placement and Removal: A Stepwise Clinical Approach

PROKERA is usually implanted in an outpatient clinic after topical anesthetic eye drops have been administered. Prior to insertion, the cryopreserved device is brought to room temperature and cleaned with sterile saline. It is then gently put on the ocular surface, with the retaining ring partially beneath both the upper and lower eyelids and suitably centered on the cornea.

The device is typically held for 4-7 days, in accordance with widely used protocols for dry eye and ocular surface disease care; however, the time of retention may vary depending on the therapeutic indication and patient response. PROKERA should not be used for longer than 29 days, according to the manufacturer's recommendations.

Under slit-lamp biomicroscopy, removal is carried out with sterile forceps. In a way akin to removing a large bandage contact lens, the retaining ring is carefully grabbed and removed from the ocular surface.

Through the Patient’s Eyes

The majority of patients, especially in the early days after implantation, have mild to severe discomfort, excessive watering, photophobia, and a foreign body sensation.Because PROKERA is located right in front of the pupil and is not a completely transparent membrane, reports of temporary blurring of vision are frequent.

Patients are typically counselled to:

• Steer clear of rubbing or putting pressure on the eye.

• Avoid swimming and close your eyes when taking a bath to avoid getting water in your eyes.

• Don't drive because you can't see as clearly.

• As instructed by the clinician, apply lubricating eye drops in addition to topical steroids and antibiotics.

• Frequent follow-up appointments are crucial for monitoring ocular surface healing, evaluating device placement, and facilitating the early identification of possible problems.

Evidence from Previous Research

Numerous clinical studies have shown that self-retained cryopreserved amniotic membrane devices, such as PROKERA, improve clinical outcomes in neurotrophic keratitis and dry eye disease by speeding up corneal epithelial recovery when compared to traditional medical therapy.(2,3) Superior results, such as increased corneal sensitivity, improved corneal nerve density, and a greater reduction in symptoms, have been documented in clinical trials comparing PROKERA to normal medical care.(7,8)

High rates of epithelial healing, together with improvements in visual acuity and a decrease in symptoms like discomfort and photophobia, have been documented in case studies involving neurotrophic keratitis and other ocular surface illnesses. (2,3) Additionally, early amniotic membrane therapy has been linked to decreased inflammation, scarring, and symblepharon forms in acute ocular surface injuries and severe inflammatory diseases. The ocular surface is preserved and restored throughout time thanks to these effects. (2,6)

Safety Concerns and Contraindications

PROKERA SLIM, according to the manufacturer's instruction, is contraindicated in the glaucoma drainage device and/or functioning filtering bleb due to the potential for mechanical irritation by the retaining ring. It must also never be reused and should not be used if the sterile packaging has been compromised.

Ocular pain, headache, displacement of the device, epithelial defects, microbial keratitis, corneal edema, or recurrences of the underlying disease have been described. During the time the ring is in situ, it may induce changes in the tear film dynamics or in the corneal topography. These changes may result in blurred vision or changes in the measurements of corneal topography.

In severe cases of ocular surface disease, there might not be adequate coverage of the deep fornix, which is a limitation compared with sutured amniotic membrane grafts. Cost and transient visual disturbances during the period of device use are other disadvantages associated with amniotic membrane repairs.

PROKERA Versus Sutured Amniotic Membrane

Unlike sutured amniotic membrane transplantation, which requires an operating room setup, PROKERA can be rapidly inserted in the outpatient clinic setting without the need for sutures or tissue adhesive. Its standardized, pre-cut, cryopreserved design allows for ease of use while preserving the biological and anti-inflammatory properties of the amniotic membrane, making it well suited for routine clinical practice.

When large epithelial defects, extensive involvement of the ocular surface, or complicated healing is present, however, sutured amniotic membrane transplantation remains of paramount importance. In clinical practice, PROKERA and sutured amniotic membrane grafts should be considered complementary therapeutic modalities and not substitutes for one another.

References

1. BioTissue Inc. Prokera® biologic corneal bandage [product information]. Miami (FL): BioTissue Inc.; 2024.biotissue?

2. McDonald MB, Sheha H, Tighe S, Tseng SCG. Amniotic membrane transplantation for managing dry eye and neurotrophic keratitis. Taiwan J Ophthalmol. 2020;10(1):13-21.pmc.ncbi.nlm.nih?

3. Hsu PS, Le Q, Chen Y, et al. Self-retained, sutureless amniotic membrane transplantation for ocular surface disease: a case series. BMC Ophthalmol. 2023;23:316.pmc.ncbi.nlm.nih?

4. BioTissue Inc. Prokera® Slim corneal bandage: product insert (Canadian). Miami (FL): BioTissue Inc.; 2020.biotissue?

5. BioTissue Inc. Prokera®: amniotic membrane supports corneal healing [patient information]. Miami (FL): BioTissue Inc.; 2025.biotissue?

6. Liu J, Sheha H, Tseng SCG. Amniotic membrane transplantation in ophthalmology: an updated perspective. Clin Ophthalmol. 2020;14:1-24.pmc.ncbi.nlm.nih?

7. Morkin MI, Hamrah P, et al. Corneal nerve regeneration after self-retained cryopreserved amniotic membrane in dry eye disease. J Ophthalmol. 2017;2017:6404918.onlinelibrary.wiley+1?

8. John T, Tighe S, Sheha H, et al. Accelerated restoration of ocular surface health in dry eye disease with self-retained cryopreserved amniotic membrane. Clin Ophthalmol. 2015;9:787-791.pmc.ncbi.nlm.nih?

9. BioTissue Inc. Prokera® Plus corneal bandage: product insert. Miami (FL): BioTissue Inc.; 2020.biotissue+1?

10. Dry Eye Doctor. Prokera® cryopreserved amniotic membrane. Vancouver (BC): Dry Eye Doctor; 2023 [cited 2025 Dec 30]. Available from: https://www.dryeyedoctor.ca/prokera-cryopreserved-amniotic-membrane.html.dryeyedoctor?