Frequency of external ocular abnormalities in our patients compared with 571 patients reviewed by Rubinstein 14 and 50 patients from a questionnaire study of Stevens15
| Strabismus | Refractive error | Nasolacrimal duct obstruction | Cataract | Coloboma | Glaucoma | |
| Rubinstein (n=571) | 71% | 56% | 37% | nm | nm | nm |
| Stevens (n=50) | 48% | 38% | 30% | 6% | 6% | 2% |
| Our patients (n=24) | 71% | 67% | 25% | 20% | 8% | 4% |