In brief No difference was detected in vision or residual refraction. This does not prove equivalence and applies only to carefully selected stable keratoconus.

Who was compared

The retrospective series included 28 eyes of 16 patients with stable keratoconus and 40 eyes of 21 controls. Corrected distance acuity was at least 20/50 before surgery, and follow-up lasted at least six months.

Six-month results

  • Uncorrected distance acuity did not differ: P=.99.
  • Residual sphere, cylinder and spherical equivalent also showed no statistical difference.
  • Four eyes required another operation, two in each group.
  • Two lenses were repositioned for rotation; one control eye developed cataract and one keratoconus eye required exchange for high vault.

What it means

A posterior-chamber phakic IOL may correct high ametropia in selected patients with stable keratoconus when corneal ablation is undesirable. It does not treat ectasia or remove irregular astigmatism. Confirmed stability, tomography, endothelial assessment, chamber depth and lens sizing remain essential.

Limitations

This was a small retrospective study that analyzed eyes rather than independent patients and followed them for six months. Failure to find a statistical difference cannot establish equal safety or effectiveness.