SEEING THROUGH THE EYE OF THE NEEDLE

To report a case of a pinhole effect intraocular lens (IOL) implantation in a pseudophakic patient with high irregular astigmatism post penetrating keratoplasty. 

Prof. Doutor Fernando Fonseca Hospital, Amadora, Portugal. 

The pinhole effect reduces the circle of least confusion by cutting down the light divergence and spherical aberrations. This principle can be adapted to IOLs like the XtraFocus Pinhole Implant™ by Morcher®. This posterior chamber IOL is composed by acrylic hydrophobic material and is indicated for secondary implantation in the ciliary sulcus. There are multiple clinical indications for its implantation such as corneal ectasias, especially advanced keratoconus, but it can be implanted after radial keratotomy, penetrating keratoplasty (PK) or after LASIK when other strategies didn’t work. We present a case of a 69-year-old female with a previous history of cataract surgery with monofocal posterior chamber IOL implantation followed by penetrating keratoplasty in the left eye (OS).

Five years later, her best corrected visual acuity (BCVA) of counting fingers mostly due to a 10 diopter irregular astigmatism. Unable to correct this astigmatism with other therapeutic options and predicting the benefits of the pinhole effect, we opted for the secondary implant of a posterior chamber IOL using the model XtraFocus™ by Morcher® in the ciliary sulcus. After the procedure, the patient was very satisfied having a BCVA of 6/10.

The use of the pinhole effect in IOL seems to be a safe and effective strategy in very well selected cases. There is a small surgical learning curve, and it offers a big improvement in the visual acuity when other strategies don’t work.