Minimum fixation angle prevents postoperative pIOL rotation

Toric phakic intraocular lens (pIOL) intraoperative fixation angle should be kept to a minimum to avoid postoperative rotation, claims a study in the Journal of Cataract and Refractive Surgery.

Dr Takashi Kjima et al., Nagoya Eye Clinic, Nagoya, Japan, conducted a case series on 34 patients implanted with a toric implantable collamer pIOL. The pIOL axis was recorded by calculating ocular internal cylinder power and the axis using the total refractive cylinder and corneal astigmatism using vector analysis.

Preoperative manifest refractive sphere, preoperative manifest spherical equivalent, mean keratometric power, axial length, toric pIOL intraoperative fixation angle, postoperative toric pIOL vault and toric spherical power were among the potential factors that were associated with toric pIOL rotation. They were all correlated with toric pIOL rotation over six months postoperatively.

Postoperative toric pIOL rotation and intraoperative toric pIOL fixation angle were strongly correlated. Mean rotation six months postoperatively was 4.82 ± 6.98 degrees. The toric pIOL was swapped for a larger toric pIOL in one eye with significant pIOL rotation.