- The original Thornton Ring was designed to fixate the globe while performing Radial and Astigmatic Keratotomy (RK and AK) (original design was fixed only and not a swivel handle)
- Degree marks were added at every ten degrees with wider grooves at every 45° for cardinal references
- Essentially provides a pattern for performing non-guided LRI incisions in a simple manner
- Properly finished teeth may redden the conjunctiva but not lead to subconjunctival hematomas
- Low profile design with no glare
- By retropulsing the globe while applying pressure to the sclera, IOP increases which improves incision depth
- Provides perhaps the most positive fixation for corneal relaxing incisions
- Note: All modern globe fixation rings have their origins based upon designs by Spencer P. Thornton, MD.