To evaluate the effect of cataract surgery on subfoveal choroidal thickness (SCT) and investigate the relationship between the variation of SCT and refractive error.

We retrospectively reviewed the medical records of 47 patients (47 eyes) who underwent uneventful phacoemulsification cataract surgery from March 2012 to February 2014. SCTs were measured using spectral-domain optical coherence tomography performed before surgery and at 1 month, 3 months and 6 months postoperatively. We investigated the differences in target refraction (TR) and postoperative spherical equivalent (SE), intraocular pressure (IOP) and central macular thickness (CMT) at all follow-ups.

Compared with preoperative measurements, SCT showed a significant increase of 5.9 ± 13.3 µm at postoperative 1 month and 7.6 ± 18.1 µm at postoperative 3 months ( p = 0.004 and p = 0.006, respectively), but no significant differences at postoperative 6 months ( p = 0.104). The correlation between the variation of SCT and the differences in postoperative SE and TR were not significant at 1 month and 6 months, but were positively significant at 3 months (r = 0.310, p = 0.034). The variation of SCT showed no significant correlations with the postoperative change in IOP and CMT.

SCT significantly increased up to 3 months after cataract surgery. The variation of SCT may affect the postoperative refractive error.