Cataract surgery in eyes with nanophthalmos and relative anterior microphthalmos

To compare the refractive outcome and postoperative complications of cataract surgery among nanophthalmos and relative anterior microphthalmos and the normal control eyes.

Retrospective case-control series.

Seventeen eyes with nanophthalmos, 29 eyes with relative anterior microphthalmos, and 54 normal control eyes were enrolled in this study. The subjects were divided into 3 diagnostic subgroups according to the following: nanophthalmos with an axial length <20.5 mm and without morphologic malformation; relative anterior microphthalmos with a corneal diameter (CD) ≤ 11 mm, an anterior chamber depth (ACD) ≤ 2.2 mm, and an axial length (AL) ≥ 20.5 mm; and normal control group eyes defined as an AL ≥ 20.5 mm with a CD >11 mm or an ACD >2.2 mm. The implanted intraocular lens (IOL) power was used to calculate the predicted postoperative refraction error according to 4 IOL power formulas: SRK II, SRK/T, Hoffer Q, and Holladay 1. With each formula, the mean numeric error and mean absolute error were calculated. At postoperative 2 months, the endothelial cell count and the complications were analyzed.

As measured by mean numeric error or mean absolute error, there was a significant difference among the 3 groups based on SRK II, SRK/T, and Hoffer Q, with less predictability in the nanophthalmic eyes. In eyes with nanophthalmos, the Holladay 1 produced the best refractive results as measured by mean numeric error (P < .001). A higher occurrence rate of posterior capsule rupture (11.7%) was shown in the nanophthalmic eyes. The difference among the 3 groups for the postoperative endothelial cell loss was not significant (P = .421).

The refractive predictability and postoperative outcome was poorer in the eyes with nanophthalmos compared to the eyes with relative anterior microphthalmos or normal control.