If you've started researching scleral lenses, you've probably run into a few different names — mini-scleral, semi-scleral, and full scleral. They're all part of the same family, and the main thing that separates them is diameter. Here's what those size differences mean for your eyes.
A quick size breakdown
- Corneal (standard RGP): ~9–11 mm — sits on the cornea (not a scleral lens).
- Corneo-scleral / semi-scleral: ~12.5–15 mm — bridges the cornea and sclera.
- Mini-scleral: ~15–18 mm — vaults the cornea, lands just past it on the sclera.
- Full scleral: ~18–24 mm — the largest, vaulting a wide margin over the cornea.
Mini-scleral lenses
Mini-sclerals are the workhorses of the scleral world. They're large enough to clear the cornea and hold a healthy fluid reservoir, but small enough to be easier to insert, remove, and handle. For many patients — mild-to-moderate keratoconus, dry eye, or lens intolerance — a mini-scleral is the ideal balance of comfort and simplicity.
Full scleral lenses
Full sclerals are reserved for more complex eyes: advanced keratoconus, severely irregular corneas, deep dry-eye needs, or post-surgical shapes. Their larger vault holds more fluid and clears even significant corneal bulges, but they take a bit more practice to handle.
How your doctor chooses
Diameter is chosen based on your corneal shape, how much vaulting you need, the health of your ocular surface, and your ability to handle the lens. There's no "better" size in the abstract — only the size that fits your eye best. That's why precise measurements and diagnostic imaging are such an important part of the fitting.
The bottom line
Whether you end up in a mini or a full scleral, the goal is identical: a smooth optical surface, all-day hydration, and stable, comfortable vision. Dr. Salley will match the diameter to your unique anatomy.
Want to know which size is right for you? Book a scleral lens fitting at CFE Memphis.