SECURE IOL POSITIONING

Scleral haptic fixation can provide a secure positioning of a replacement intraocular lens (IOL) in patients who require IOL exchange due to late subluxation of the lens and capsular bag, according to Gábor B Scharioth MD, PhD, Augenzentrum Recklinghausen, Germany, and University of Szeged, Hungary.

“This is a real sutureless technique and that means that we are not depending on the stability of the suture material. Prolene sutures, as are used in most cases, have a tendency to break after eight to 12 years, making refixation necessary,” Dr Scharioth told the 15th EURETINA Congress in Nice, France.

He noted that the incidence of late IOL and capsular bag subluxation – generally occurring many years after IOL implantation – has increased markedly over the past decade. A study carried out in Sweden showed that the trend began there with patients who underwent cataract surgery after 1992.

“Before 2000 most of the IOLs were not implanted into the capsular bag and therefore dislocation occurred mainly in the early postoperative phase. That is different from the situation we are faced with today,” Dr Scharioth said.

Dr Scharioth noted that he opts for re-centration of a decentred intracpasular IOL only if the capsular bag is intact and the zonules are quite strong. In most such cases he uses, after reopening of the capsular bag, a capsular tension ring to improve centration.

In most eyes with weak zonules the capsular bag is filled with excessive secondary cataract. Furthermore, often Nd:YAG laser capsulotomy was already performed and often laser pitts are present in the IOL optic. Dr Scharioth added that IOL re-fixation in eyes where there is a dislocated capsular bag can result in posterior capsular opacification material falling into the vitreous during the surgery. He noted that pars plana infusion will reduce that occurrence during explantation of a subluxated capsular bag-IOL-complex.

When there is subluxation of the entire capsular bag and IOL complex, he opts for explantation of the lens and implantation of a replacement IOL using the scleral fixation technique he introduced 10 years ago.

The scleral fixation technique involves first creating two ciliary sulcus sclerotomies 1.0mm to 2.0mm behind the limbus and exactly 180° apart, then using the scleral incisions to prepare a limbus-parallel intrascleral tunnel.

That is followed by implantation of the IOL with a handshake manoeuvre, passing the haptic from one hand to the other with two special endo forceps. The haptics are then drawn into position and fixated into the limbal scleral tunnel without any suture.

“So far we have not found any contraindication to this technique. It is a standardised technique that can be used with standard IOLs with predictable refractive outcome, low complication rate and excellent long-term stability,” Dr Scharioth added.

Gábor B Scharioth: gabor.scharioth@augenzentrum.org