Abstract
Purpose: :
To describe the evolution of a new technique for scleral fixation of intra–ocular lens (IOL) with minimal manipulation of the conjuntiva – for repositioning a dislocated IOL into the vitreous cavity or for secondary implant of IOL in eyes without capsular support. This can be achieved with minimal manipulation of the conjuntiva using transcleral vitrectomy 25–gauge (tsv25).
Methods: :
Two triangular, limbal based, 2 mm partial–thickness scleral flaps are placed in opposite sides avoiding the rectus muscles meridians. A clear cornea incision is performed and also a pars plana vitrectomy using tsv25 technology in order to provide IOL manipulation. For repositioning a dislocated IOL into the vitreous cavity a PFCL (perfluorocarbon liquid) may be used to protect the macula and also to facilitate the IOL grasping with a 25–gauge forceps. IOL is anteriorized into the AC and one of the haptics is fixed with an iris hook. Vitrectomy is completed, being more aggressive at the vitreous base near the scleral flaps. A 10–0 single armed prolene (3/8, 0.65 cm curved needle) is inserted into the posterior chamber assisted by a 30 gauge needle through a puncture at the bed of the distal flap, 1 mm from the limbus. The mid part of the suture is grasped with a Kelman–McPherson forceps from a clear cornea incision and then preloaded onto a silicone tube taken from a soft tip cannula as a clove hitch knot. At this stage the IOL haptic portion is grasped and temporarily externalized through the clear corneal incision. The haptic tip is inserted into the silicone tube and the clove hitch knot is transferred and tied to the haptic shaft. The iris hook now is used to retract the iris in order to facilitate repositioning of the other haptic at the anterior chamber. The same procedure is performed with this second haptic, to be sutured at the proximal flap. The outstaying curved needles are used at the bed of the flaps to complete the scleral fixation sutures and tied with a slipknot plus two conventional knots. The scleral flap is then closed with a dissolving suture.
A similar procedure can be applied for secondary implantation of IOL.
Results: :
The surgery is feasible with 20–gauge or with 25–gauge hardware. With the tsv25 there is less manipulation of the conjuntiva. Previously described surgery with 20–gauge hardware (25 cases) where reproduced with 25–gauge (2 cases). Altogether, 13 patients underwent IOL replacement (one tsv25) and 14 patients underwent secondary implant of IOL (one tsv25).
Conclusions: :
The tsv25–gauge technique can be applied with the clove hitch knot for repositioning a dislocated IOL into the vitreous cavity or for secondary implant of IOL in eyes without capsular support
Keywords: intraocular lens • vitreoretinal surgery • treatment outcomes of cataract surgery