A case report on the change of the refractive power after a blunt trauma

To determine the pathogenesis of transient myopia after blunt eye trauma.

In one patient, the refraction of both eyes (the left eye was injured, but the right eye was not) was measured with an autorefractometer. The cycloplegic refraction was measured at the early stage of trauma and again 3 months after the blunt eye injury. The angle and depth of the anterior chamber, the ciliary body, and the choroids were examined by ultrasound biomicroscopy (UBM) over 3 months. The depth of the anterior chamber, the thickness of the lens, and the axial length were measured by A-scan ultrasonography in both eyes. During the 3 months after the injury, we made comparisons between the menifest and the cycloplegic refractions, the depths of anterior chambers, the thickness of the lenses, the axial lengths, and the UBM-determined appearances of the angles and depths of the anterior chambers, the ciliary bodies, and the choroids in both eyes.

We suspect that the depth reduction in the anterior chamber, the increase in anterior to posterior lens diameter, and the edema in the ciliary body are all related to the change in the refractive power following the blunt trauma.

Ultrasound biomicroscopy (UBM) and ultrasonography of the anterior segment in the eye may be helpful to diagnose and confirm changes in the refractive power that occur after trauma.