Mean (SD) for the five raw vision measures* and three difference measures† in normals, keratoconus, and penetrating keratoplasty subjects
| Normal (n = 24) | Keratoconus (n = 11) | PK (n = 21) | Statistics | |
|---|---|---|---|---|
| *Visual acuity (VA), low contrast visual acuity (LCVA), low contrast visual acuity under glare (LCVAglare) (all in logMAR), Pelli-Robson contrast sensitivity (PRCS), Pelli-Robson contrast sensitivity measured under glare (PRCSglare) (both in logCS). | ||||
| †Low contrast loss = LCVA − VA, low contrast glare loss = LCVAglare − LCVA, PRCS glare loss = PRCS − PRCSglare. | ||||
| Age | 33.7 (8.6) | 35.0 (11.1) | 41.2 (7.9) | |
| Visual acuity | −0.18 (0.05) | 0.17 (0.22) | −0.03 (0.11) | (F2,48 = 30.60; p<0.001 post hoc normal<keratoconus, p<0.001, normal<PK, PK<keratoconus, p<0.01) |
| Low contrast visual acuity | −0.12 (0.06) | 0.29 (0.23) | 0.10 (0.12) | (F2,48 = 41.70; p<0.001 post hoc normal<keratoconus, normal<PK, p<0.001, PK<keratoconus, p<0.01) |
| Low contrast visual acuity under glare | −0.11 (0.08) | 0.35 (0.28) | 0.08 (0.14) | (F2,48 = 31.87; p<0.001 post hoc normal<keratoconus, normal<PK, p<0.001, PK<keratoconus, p<0.01) |
| Pelli-Robson contrast sensitivity | 1.80 (0.13) | 1.10 (0.28) | 1.39 (0.22) | (F2,51 = 50.69; p<0.001 post hoc normal>keratoconus, normal>PK, p<0.001, PK>keratoconus, p<0.01) |
| Pelli-Robson contrast sensitivity under glare | 1.73 (0.11) | 1.25 (0.46) | 1.41 (0.21) | (F2,49 = 17.09; p<0.001 post hoc normal>keratoconus, p<0.001, normal >PK, p<0.01) |
| Low contrast loss | 0.05 (0.04) | 0.15 (0.12) | 0.12 (0.09) | (F2,48 = 6.16; p<0.01 post hoc normal<keratoconus, p<0.05) |
| Glare loss (low contrast visual acuity) | 0.02 (0.08) | 0.06 (0.11) | −0.02 (0.08) | (F2,49 = 4.23; p<0.05 post hoc keratoconus>normal, p<0.05) |
| Glare loss (Pelli-Robson contrast sensitivity) | 0.07 (0.11) | −0.16 (0.36) | −0.01 (0.21) | |