Femto laser cataract pretreatment induces miosis

This retrospective study confirmed that femtosecond laser pretreatment during cataract surgery induced significant miosis, and this was most strongly correlated with laser treatment duration and patient age.

The authors wrote that a high incidence of intraoperative miosis has been the most frequently reported complication by experienced femto laser-assisted cataract surgeons, and this could negate the advantages of femto laser pretreatment. They note that in conventional cataract surgery, preoperative miosis is closely linked to intraoperative complications, including posterior capsule rupture with or without vitreous loss.

They included 56 eyes and found that their mean pupil area decreased significantly by 29.7% during the time it took to shift between femtosecond laser pretreatment and phacoemulsification. Pupil constriction to less than 6.0 mm after laser treatment occurred in more than 40% of patients.

Overall decrease in pupil area was mainly correlated with the length of time it took to use the laser to fragment the lens and to create the primary corneal incision.

Additionally, pupil constriction was significantly correlated with patient age, with older patients having a greater reduction, but not with suction-on time or time between procedures.

The authors recommend further studies on the role of intraocular prostaglandins and other aqueous humor factors related to laser-induced pupil constriction, as well as on proper dilating regimens and the effect of NSAIDs in preventing intraoperative miosis after femtosecond laser pretreatment.