Amniotic membranes for dry eye disease in an outpatient setting

Amniotic membrane (AM) transplantation has an established role in ophthalmology for the treatment of ocular surface disease due to its anti-inflammatory and anti-scarring effects, along with the delivery of growth factors that promote epithelial wound healing on the surface of the eye.¹

AMs are traditionally administered by ophthalmologists in a theatre. However, a CE-marked product is now available in the UK that may be applied in an outpatient setting.² The AM is supplied in a dry, preserved state and can be stored for up to 48 hours at a temperature between 2–25°C without the need for a tissue storage licence. It is also supplied with a bandage contact lens that has been specifically designed for this product, which holds the AM in situ on the ocular surface.

What is an AM?

AM is the innermost layer of the placental sac, which protects and holds the foetus during pregnancy. It can be extracted from placental tissue obtained during elective caesarean sections and transformed in to a sterile and stable regenerative therapy for managing specific cases of dry eye disease (DED).³ To ensure that the AM is safe for use, donors are screened against strict criteria in line with the regulatory standards of the Human Tissue Authority (HTA) Guide to Quality and Safety Assurance for Human Tissue and Cells for Patient Treatment.⁴

Indications for use

AMs have been shown to improve the ocular surface and reduce the severity of dry eye workshop (DEWS) scores.⁵ A review of the literature shows there is good evidence to support the safety and effectiveness of AM in restoring corneal epithelial health, improving visual acuity in eyes with neurotrophic keratitis and DED, and alleviating symptomatic DED.⁶ While further trials are ongoing,⁷ a small-scale randomised controlled trial outlines that AMs offer a promising therapy for corneal nerve regeneration and accelerated recovery of the ocular surface health in patients with DED.⁸

The Tear Film and Ocular Surface Society (TFOS) DEWS II Management and Therapy Report highlights that AMs can be considered as a fourth step in its staged management and treatment recommendations for DED where other options are inadequate.⁹

Contraindications for use

Patients may be sensitive to the ingredients used to clean and disinfect the tissue samples. Practitioners should familiarise themselves with the contraindications listed by the manufacturer and have robust procedures in place to show that patients have been properly screened for suitability.

Practitioners should also be mindful that patients may be sensitive to these ingredients without realising it, and any sensitivity reactions which occur following the procedure will need to be managed appropriately.

What training is required to use AMs?

Practitioners are required to undergo training with the product manufacturer prior to being authorised to treat patients in clinic and will receive a certificate to evidence that they have been successful.

Aspects of the training include:

• The background of AMs
• An explanation about the HTA’s jurisdiction over human-derived tissues and cells in the UK
• How to store an AM
• Patient exclusion criteria 
• How to obtain appropriate patient consent using the form provided by the manufacturer
• Loading and insertion techniques for the AM
• How to remove the AM and appropriate clinical waste disposal
• How to maintain a traceability log

Obtaining consent for the use of an AM

You should ensure you are familiar with the General Optical Council (GOC) guidance on obtaining consent,¹⁰ but in summary you should consider the following points:

• Consent is a process which involves a dialogue with the patient; it is not simply obtaining a signature on a form
• To obtain valid consent, it is important that the patient is provided with sufficient information to make an informed decision about treatment
• This means the patient must be given clear and accurate information about the risks and benefits of treatment in a way they can understand and that explains how these may affect them personally
• You should ensure that your clinical records demonstrate that this discussion has taken place and you should record any concerns that the patient raises

Does my AOP insurance cover the use of AMs?

AOP membership includes medical malpractice cover for work which is within the scope of normal optometric practice. As AMs are applied in a similar way to contact lenses, we consider these to be within the scope of practice for optometrists. As long as you have completed appropriate training which can be verified, and your employer has approved you to carry out this work, the medical malpractice insurance part of your AOP membership will cover this procedure.

References

1. Meller D, Pauklin M, Thomasen H, Westekemper H, Steuhl KP. Amniotic membrane transplantation in the human eye. Dtsch Arztebl Int 2011 Apr;108(14):243-8
2. www.nu-vision.co.uk/omnilenz/
3. Mcgaughy AG, Gupta PK. In-Office Use of Amniotic Membrane. Amer Acad Ophthalmol. EyeNet Magazine February 2015
   www.aao.org/eyenet/article/in-office-use-of-amniotic-membrane 
4. Human Tissue Authority. HTA Guide to Quality and Safety Assurance for Human Tissues and Cells for Patient Treatment. January 2021 
5. McDonald MB, Sheha H, Tighe S, et al. Treatment outcomes in the DRy Eye Amniotic Membrane (DREAM) study. Clin Ophthalmol 2018 Apr 9;12:677-681
6. Mead OG, Tighe S, Tseng SCG. Amniotic membrane transplantation for managing dry eye and neurotrophic keratitis. Taiwan J Ophthalmol 2020 Mar 4;10(1):13-21
7. Travé Huarte S, Wolffsohn J. Dry eye OmniLenz application of Omnigen Research Study (DOORS). RCO 2023  
8. John T, Tighe S, Sheha H, et al. Corneal Nerve Regeneration after Self-Retained Cryopreserved Amniotic Membrane in Dry Eye Disease. J Ophthalmol 2017;2017:6404918
9. Jones L, Downie LE, Korb D, et al. TFOS DEWS II Management and Therapy Report. Ocul Surf 2017 Jul;15(3):575-628
10. General Optical Council. Supplementary guidance on consent