To report a case of cataract surgery using a piggyback method in a patient with pure nanophthalmos with an axial length under 16.00 mm in both eyes.

The authors performed cataract surgery using a piggyback method inserting two intraocular lenses (IOLs) in a 44-year-old male with nanophthalmos with axial lengths of OD 15.36 mm, and OS 15.59 mm. Primary implantation of two IOLs of +53.0D as calculated by the SRK/T and Holladay formula was performed in the right eye using a piggyback method. In the left eye, two IOLs of +60.0D calculated by the Hoffer Q formula were implanted. Postoperative hyperopic refractive errors occurred in both eyes. The differences between the preoperative target spherical equivalent (SE) and the postoperative one year four month SE were 9.68D in the right eye and 1.63D in the left eye.

Due to high diopter IOL requirements in nanophthalmic patients (less than 16.00 mm) during cataract surgery, the refractive errors were well corrected, without complications, by using a piggyback method. In the present case study, the Hoffer Q formula produced better results than did the SRK/T or Holladay formula in reducing the difference in preoperative and postoperative SEs, but more surgical cases and research are required to establish the most appropriate formula for cataract surgery in nanophthalmos.