Is A Soft Contact Lens Holiday Necessary? Assessing Changes In Intra-Ocular Lens Selection Following Immediate Versus Delayed Biometry

To evaluate the impact of immediate soft contact lens (SCL) removal on biometric accuracy and IOL power selection. While clinical guidelines recommend a lens holiday, patients often attend pre-assessment wearing lenses. This study aims to determine the extent of biometric stability versus clinical change after a one-week holiday and identify the anatomical drivers of any observed IOL power shifts.

This prospective study was conducted in the cataract clinic of Moorfields Eye Hospital, City Road between 2024 and 2025.

Prospective study of 24 eyes. New patients presenting to their first appointment in the cataract service in soft contact lenses underwent immediate biometry (IOLMaster 700) after lens removal. These measurements were not used for surgical planning. Patients returned after a one-week contact lens holiday for repeat bioemtry. Parameters compared included axial length (AL), average keratometry (Kavg), central corneal thickness (CCT), exact IOL power (calculated using Barrett Universal II formula), and predicted residual spherical equivalent (SE). Statistical analysis used paired t-tests and Pearson correlation to assess the relationship between biometric shifts and IOL choice.

Twenty-four eyes were analyzed. Mean exact IOL power (diff: -0.085±0.36D, p=0.265), AL (diff: 0.11mm, p=0.40), and CCT (p=0.78) showed no statistically significant differences across the group. However, the final clinical IOL choice changed in 37.5% of cases (9/24 eyes) following the holiday. A very strong negative correlation was found between change in Kavg and change in exact IOL power (r = -0.94), whereas AL and CCT remained stable. This confirms that transient corneal curvature alterations rather than axial changes drive the observed IOL power discrepancies in individual patients.

Although mean biometric values remain statistically stable after soft contact lens removal, individual corneal curvature variations lead to a change in clinical IOL selection in over one-third of patients. Axial length and corneal thickness are unaffected by soft contact lens wear. These findings demonstrate that a one-week holiday is essential to mitigate individual corneal "molding" effects and ensure refractive precision in cataract surgery.