Scleral Saline- To Buffer or Not to Buffer?

Scleral saline plays a critical role in the health and comfort of your eyes. If you wear scleral lenses, you understand the importance of preservative-free saline. The reason is simple: whatever solution you use stays in constant contact with your cornea for extended periods. Even mild preservatives can lead to irritation, discomfort, and reduced wearing time.

While the importance of preservative-free saline in scleral lens success is widely known, certain details, like whether to use buffered or non-buffered saline, can often be overlooked or misunderstood.

What are buffers in scleral saline?

Buffers are chemicals added to saline solutions. Buffers maintain the pH level of the filling solution to a fixed level. The most common buffers are Borate and Phosphate.

Borate is a common buffer made of boric acid and sodium borate. Some scleral lens wearers find that it adds comfort and allows them to wear their lenses longer. However, reports of allergic reactions or sensitivities have been linked to borate.

Phosphate is also used to add comfort to scleral lens wear. As with Borate, some patients find the additive beneficial to their comfort and overall wearing experience. Although rare, phosphate can interact with calcium in natural tears, increasing the deposition of the lens.

Buffered vs. Non-buffered: Advantages and Disadvantages

Buffered saline maintains a stable pH closely matching your natural tears. This is accomplished by the solution’s fixed pH level, which mimics the natural tear. Buffers create a challenge for the natural tear to overcome and adjust as needed. Some patients have experienced irritation from the added chemicals and find the cost and availability of buffered saline to be an obstacle, while some patients prefer the fixed pH of buffered saline. 

Non-buffered saline lacks the added chemicals, helping to maintain a more natural balance in the tears and allowing the body to instinctively adapt. An example is when an irritant, like smoke or dust, enters the eye. When this happens, the tears become more acidic. Natural tears have the ability to adjust by increasing tear production to flush out the irritant and bring the pH level back to the normal range. This process is essential in protecting the ocular surface. Some patients may find the lack of additives beneficial, and enjoy the lower price of non-buffered saline. 

Clinical studies have shown that both buffered and non-buffered saline solutions provide a comparable user experience when it comes to comfort, safety, and eye health. Ultimately, the choice between buffered and non-buffered saline depends on individual preferences, comfort, and eye health requirements. Discuss the options with your eye care practitioner.

Conclusion

Choosing the right saline solution for your scleral lenses is crucial for maintaining comfort and eye health. Both non-buffered and buffered saline solutions offer unique comfort and eye health benefits. While there isn't strong evidence suggesting one is superior to the other, the most important factor for a positive experience is using sterile, preservative-free saline to keep your eyes safe and healthy.


Did you know? We recently added Tangible Fill to our innovative family of products. This FDA-approved, unbuffered scleral filling and rinsing solution rounds out the Tangible system and works harmoniously with Tangible Hydra-PEG, Clean, and Boost.

Learn more: https://tangiblescience.com/products/tangible-fill