Optimising Patient Selection For Refractive Procedures In Eyes With Corneal Pathology: An Audit Of Screening Algorithms, Surgical Decision-Making And Intraocular Lens Selection

To evaluate a practical, evidence-informed pathway for selecting refractive interventions (corneal laser, phakic IOL, or refractive lens exchange/toric IOL at cataract surgery) in patients with pre-existing corneal pathology. The paper compares outcomes and decision concordance when using advanced corneal tomography/biomechanics, endothelial assessment and a decision algorithm that balances ectasia risk, optical regularity and endothelial health to guide whether to treat the cornea, implant a phakic IOL, or proceed with lens-based refractive solutions. Key aims: (1) describe the algorithm; (2) audit how often it changes planned management; (3) report short-term visual and safety outcomes by chosen pathway.

Single-centre retrospective audit (tertiary refractive/cataract unit) of consecutive patients assessed for refractive surgery between January 2022 and December 2024 who had documented corneal pathology or topographic irregularity (suspicious tomography, prior keratitis scarring, mild posterior ectasia indicators, or healed superficial scarring).

We audited 180 eyes of 120 patients assessed for refractive correction. 
• Proceed to corneal laser (PRK/advanced surface ablation or limited LASIK) only if BAD-D within normal limits, pachymetry sufficient, and topographic regularity confirmed. 
• Consider phakic IOL when corneal topography shows irregularity but spectacle-corrected acuity is good, anterior chamber depth and endothelial density meet safety thresholds (ACD ≥3.0 mm; ECD thresholds age-adjusted).
• Lens-based solutions  when corneal irregularity impairs corneal-based ablation predictability
Primary endpoints: change in intended treatment after algorithm application, uncorrected and best-corrected visual acuity at 3 months, refractive predictability (±0.5 D), and adverse events

Algorithm application altered the originally planned intervention in 42% of cases (e.g., from planned LASIK to phakic IOL or to lens-based management) — primarily due to ectasia risk indices or low endothelial reserves. At 3 months, eyes selected for corneal procedures (n = 52) achieved mean UDVA improvement and refractive predictability comparable to published benchmarks; eyes routed to phakic IOL (n = 68) demonstrated high spectacle independence with preserved endothelial counts at 3 months; lens-based group (n = 60) achieved predictable cylinder correction when toric IOLs were used with topography-informed planning. No cases of postoperative ectasia were observed during the short follow-up. 

A structured selection algorithm that integrates tomography-based ectasia indices (e.g., BAD-D), pachymetry, biomechanical data and endothelial assessment materially alters management in a substantial minority of patients with corneal pathology. Tailoring the intervention to objective corneal and anterior-segment metrics—favoring phakic IOLs or lens-based solutions where corneal laser predictability or safety is reduced—appears to preserve safety and deliver satisfactory refractive outcomes in the short term. Larger prospective and longer-term studies are needed to confirm durability and endothelial safety