The effect of contact lens wear on retinal spectral domain optical coherence tomography.

BACKGROUND

This study assessed the impact of contact lens wear on retinal spectral domain optical coherence tomography (SD-OCT) image quality and macular thickness measurements, among subjects with myopia.

METHODS

This was a prospective study including 34 subjects (26.59 ± 3.19 years) with myopia or myopic astigmatism. Twelve were imaged wearing spherical soft contact lenses, eight non-contact lens wearers were imaged with a plano soft contact lens, and 14 with significant astigmatism were fitted with a rigid gas permeable (RGP) contact lens. For each group of contact lens types, the average image quality index (Q-index), and the average macular thickness measurements were compared between macular OCT scans obtained from the same eyes with and without a contact lens.

RESULTS

Among the subjects assessed with their habitual spherical soft lenses, the average Q-index was similar for scans acquired with and without a contact lens (30.10 ± 1.94 versus 31.03 ± 2.55; p = 0.18). Among non-contact lens wearers, the average Q-index was slightly higher for scans acquired without a contact lens, compared to scans with a plano contact lens (31.99 ± 2.06 versus 29.51 ± 1.56; p = 0.006). Among 14 subjects imaged wearing a fitted RGP contact lens, the Q-index was similar for scans acquired with and without a contact lens (29.04 ± 2.73 versus 28.75 ± 2.86; p = 0.78). In all groups, there were no correlations between the power of the sphere and change in the Q-index (that is, post- minus pre-contact lens Q-index), and no differences were found between OCT-derived macular thickness measurements from scans with and without a contact lens. The magnitude of cylinder was not correlated with the change in the Q-index in the habitual and RGP contact lens groups. However, an inverse correlation between cylinder power and change in the Q-index was found in the plano contact lens group.

CONCLUSION

In low to intermediate levels of myopia, with or without regular astigmatism, macular SD-OCT imaging does not merit placement of a soft or rigid contact lens, nor is there an added benefit from removing a habitual spherical soft lens prior to scanning.