A vault scan measures the distance between an implantable collamer lens (ICL) and the natural crystalline lens using anterior segment imaging. Adequate vault is crucial for safety and optimal vision after ICL surgery.
How It Is Performed
Anterior segment OCT or Scheimpflug imaging (for example, Pentacam) is used to capture cross‑sectional images of the ICL and lens.
- The vertical separation between the back of the ICL and the front of the crystalline lens is measured, usually in micrometres.
- Scans may be taken centrally and at multiple meridians to assess uniformity.
- Measurements are repeated over time to ensure stability.
- The test is quick, non‑contact, and comfortable for patients.
Why Vault Matters
Vault that is too low or too high can lead to complications.
- Low vault increases the risk of lens-ICL contact and earlier cataract formation.
- Excessively high vault can narrow the angle and predispose to raised eye pressure.
- Findings may prompt closer monitoring or, in selected cases, ICL exchange.
- Pre‑operative sizing, guided by biometry and anterior chamber depth, aims to achieve an ideal vault range.
