Learn the Pupil Stretch Technique

Stretching the pupil during cataract surgery is a safe and effective way to improve access via mechanical dilation. While there are special instruments available to perform this technique, I have found that simply using two choppers or similar instruments (Y-hook, Push-Pull, etc) is easy and effective. The pupil is stretching towards the angle of the eye and this will cause micro-tears in the sphincter and pupil margin. Next, visco-mydriasis using the viscoelastic is effective to hold the pupil open during capsulorhexis creation. In this case, we started with a 4 mm pupil and ended with a 5.5 mm pupil.

How does it compare to using other methods of pupil expansion? It turns out that all of these methods (stretching, iris hooks, pupil rings) cause about the same degree of total stretching and the circumference of the expansion is about the same.

This technique is easy to learn — click below to watch the video:


  1. Great video, I always try pupilar stretch before bothering with a pupil ring. Stretching does the job in 4 out of 5 cases in my experience.
    The black spots on this patient’s limbus irritate me, they don’t look like melanosis. Was this post ocular trauma – and if so does this change your approach to surgery?

    1. great points. The black dots are just ink marks for marking the cardinal meridians as a back-up check for toric IOL alignment. This eye was not post-trauma.

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