Since cataracts are located just behind your pupil, the size of your pupils is an important factor in the success of cataract surgery. So the eyedrops will be used to dilate your pupils before the procedure. Once dilated, the clouded natural lens and other structures will be seen within your eye in greater detail, then your cataracts will be allowed to safely removed.Once your cataracts have been removed, the doctore will re-constrict your pupils using another type of eyedrop, since your new intraocular lens (IOL) will be implanted in front of your pupil and iris. Depending on the type of IOL you have implanted, your pupils may remain dilated for a week or more after cataract surgery. During this time, you will need to use pupil-constricting eyedrops until your pupils return to their normal size.As your pupils start to naturally constrict again and your eyes adjust to the IOL, your vision will become gradually clearer. Some people have excellent vision immediately after surgery, while others may need to wait for their temporary blurry vision to dissipate.
A well dilated pupil increases the ease of cataract surgery, it is difficult to perform cataract surgery on any patient with pupil size less than 5mm. During the pre-operative assessment, dilatation of the pupil is a very important parameter to be observed, as well as diagnosis of the cause of a poorly dilating pupil. If the pupil does not dilate fully, performing phaco surgery is going to be difficult. It is also important to remember not to dilate the pupil 48 hours before the surgery and with strong dilating agents like atropine, homatropine or cyclopentolate. In that case, the pupil will not dilate fully on subsequent attempt on the surgical day.