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    By Amar Agarwal, MD
    5th Annual Global Video Contest
    04:57
    Cataract/Anterior Segment

    Pinhole pupil by definition is a pupil contracted to the size of a pinhole. Significant irregular corneal astigmatism leads to ocular aberrations. High astigmatism can occur in radial keratotomy, penetrating keratoplasty, corneal injuries, intra-corneal ring segments or keratoconus. To solve the problem one can use pinhole IOL or a Trindade Xtra focus IOL, deep anterior lamellear keratoplasty (DALK), limbal relaxing incision, penetrating keratoplasty or LASER procedure. PPP leads to significant improvement in the visual acuity of patients with higher order aberrations due irregular corneal astigmatism by allowing the passage of light through the central pinhole area and barring the rays of light arising from the distorted peripheral cornea.