PROSE Lens​

Prosthetic Replacement of the Ocular Surface Ecosystem (PROSE) is FDA approved customized, computerized designed and manufactured prosthetic device. For those with keratoconus, dry eye syndrome, uneven corneas, or scarring, PROSE lenses are fitted to cover irregular corneas with a smooth, protective surface.

Because these lenses cover a greater area of the surface of the eye than traditional contact lens do, they help patients with irregularly shaped or injured corneas to receive better vision correction. For those who have not had success with conventional contact lenses or who need more specialised eye care, these are useful option.

PROSE Contact Lenses are made up of medical-grade, hard plastic material. It is highly gas- permeable and allows proper oxygen to the cornea. PROSE lens diameter range from 15 mm to 23.0 mm.

Working of PROSE Lens:

PROSE lenses are filled with sterile saline which creates a space between the lens and cornea that acts as a reservoir of artificial tears. The lens does not touch the cornea and the pool of artificial tears provides constant lubrication to the diseased cornea and helps in maintaining a smooth optical surface.

Residual spherical and cylindrical refractive error and asphericity are incorporated into the lens which improves blurry vision by creating a smooth optical surface and correcting corneal surface irregularities.

Treatments with Prose Lens help to support healing and soothe symptoms by creating a healthy ocular surface environment. It also protects the cornea from further damage caused by eyelids and the environment by acting as a barrier.

Indication of PROSE:

Corneal Ectasias:

In corneal ectasia, the cornea progressively thin and protrudes outward, impairing vision and causing distortion. It is diagnosed by a weak corneal structure, that results in the loss of the original curvature. Following are few examples:

• Keratoconus, Keratoglobus, 
• Pellucid marginal degeneration (PMCD),
• Terrien’s marginal degeneration (TMCD),
• Post LASIK Ectasia

Ocular Surface Disorders:

A collection of diseases that primarily affect the cornea and conjunctiva on the surface of the eye are commonly referred to as ocular surface disorders or OSDs. Such conditions result in pain, vision problems, and in rare cases, severe damage to the eyes. Following are few examples:

• Dry Eye (Sjogren’s syndrome)
• Limbal Stem Cell Deficiency (LSCD)
• Stevens-Johnson Syndrome (SJS)  
• Chemical Injury, Graft Versus Host Disease (GVHD)
• Ocular Cicatricial Pemphigoid, Trigeminal Nerve Dysfunction 
• Lagophthalmos Paralytic/Anotomical, Ectodermal Dysplasia etc.

Irregular Corneal Surface:

In this condition, cornea which is usually smooth and transparent develops or becomes irregular in its form due to surgery, it causes distortions in vision. Following are few examples:

• Corneal Degeneration and Dystrophies 
• Corneal Transplant ( PK PKP )
• Radial Keratotomy, LASIK, Epikeratophakia
• Corneal Scar after trauma / infection etc.

Goal Of PROSE Lens: Improve the quality of life in patients with complex corneal disease by improving vision, ocular comfort and support to the ocular surface.

Customization of PROSE lens: Utilising diagnostic fitting sets, PROSE Providers start a patient’s treatment based on a parent trial device with a certain diameter and sagittal depth. The trial PROSE device’s ocular customisation is assessed using a slit lamp biomicroscope. Using a device called a retinoscope the practitioner performs an over-refraction in order to assess visual potential. The customised PROSE device for the patient’s eye will then be made by the PROSE Provider using the personalised evaluation and over-refraction data to make adjustments and enhancements.

PROSE Providers use a proprietary computer-assisted design program to alter or modify the device design using spline functions. Next, the design is sent into advanced lathing machines that produce extremely toric and spherical lenses on-site. To allow for settling, the initial customised device’s design is evaluated both immediately upon application and again a few hours later. Design refinement is an iterative process that involves making little adjustments that are then tested one after the other visually to ensure the best possible design and physiological performance. Before PROSE devices are given to patients, professionals provide each patient with personalised instructions on how to apply and remove the devices as well as how to clean, disinfect, and store them.

An optimal customization of a PROSE device is determined by the following characteristics:

1. Proper corneal clearance
2. Landing zone alignment
3. Proper physiological function
4. Patient’s vision correction and comfort

Advantages of PROSE:

1. Improve vision in advance Keratoconus Post Radial Keratotomy, Post LASIK Ectasia’s PMCD TMCD etc. Provide relief from the pain, and dryness and reduce photophobia in dry eye diseases.    
2. Improve corneal health in the ocular surface disorder diseases such as SJS, dry eye, Graft versus host diseases etc.

Disadvantages:

Costly

How to apply Prose Lens:

1. Wash hands with water and non-moisturizing soap. 
2. Dry hands completely with a lint-free towel.
3. Place the prosthetic device in the palm.
4. Gently place the lens on the designated plunger.
5. Fill the device with the prescribed preservative-free saline. 
6. Hold the plunger vertically. 
7. The saline should be retained on the lens to avoid bubbles. (Overfilling the lens can help to achieve a bubble-free application)
8. Open your eyes wide.
9. Position the device in the centre of the eye-opening.
10. Once applied, check the position of the device and detect the presence of bubbles. If bubbles are present, the device must be removed and reapplied.

PROSE – It should be taken from the certified speciality contact lens consultant for better ocular health as these eyes are already compromised due to the corneal ectasia [Keratoconus PMCD TMCD Post Lasik Ectasia Post Radial Keratotomy (Post RK)] or ocular surface dry eye condition.