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Purpose To compare clinical and topographic outcomes of corneal allogenic intrastromal ring segments (CAIRS) vs topography-guided photorefractive keratectomy combined with corneal collagen crosslinking (TG-PRK + CXL) in the management of keratoconic patients with unsatisfactory vision with glasses or contact lenses.Methods A retrospective audit included 33 eyes of 28 patients treated with CAIRS and 77 eyes of 64 patients treated with TG-PRK + CXL, with a minimum follow-up of 6 months. Outcomes assessed were best-corrected visual acuity (BCVA), corneal steepening, astigmatism and corneal aberrations.Results Both procedures produced statistically significant improvements in visual and topographic parameters (p<0.05). TG-PRK + CXL achieved significantly greater BCVA improvement (0.258 LogMAR) compared with CAIRS (0.165 LogMAR). Significant average corneal flattening was observed in both groups (CAIRS: 2.70 D; TG-PRK + CXL: 2.21 D), along with reductions in astigmatism (1.14 D and 0.78 D, respectively). CAIRS resulted in larger reductions in lower-order aberrations (26.6% vs 16.9%, p<0.05) and higher-order aberrations (24.1% vs 14.6% p<0.05); however, these greater aberration reductions were not associated with superior visual outcomes.Conclusions Both CAIRS and TG-PRK + CXL are effective treatments for keratoconus. CAIRS offers meaningful topographic improvement and may be preferable in thin corneas or when tissue preservation is required. TG-PRK + CXL provides superior functional visual outcomes, likely due to targeted correction of visually significant aberrations within the optical zone. These findings suggest that the location and type of aberration correction are more critical for visual function than the overall magnitude of aberration reduction.