In ophthalmology, glued intraocular lens or glued IOL is a surgical technique for implantation, with the use of biological glue, of a posterior chamber IOL (intraocular lens) in eyes with deficient or absent posterior capsules. A quick-acting surgical fibrin sealant derived from human blood plasma, with both hemostatic and adhesive properties, is used.
History In 1997, Maggi and Maggi were the first to report the sutureless scleral fixation of a special IOL. The sutureless intrascleral fixation of a posterior chamber IOL was first described by Gabor Scharioth. This technique was further modified by making scleral flaps and creating scleral pockets for tucking the haptics. The flaps are then reattached to the bed with the help of glue. On 14 December 2007, the first glued intraocular lens (IOL) surgery was performed, at Dr. Agarwal's Eye Hospital in Chennai, India. This new surgical procedure was invented and performed by Amar Agarwal. Subsequently, the first child on whom a glued IOL surgery was performed was a patient who had a history of injury to her right eye 3 months before, while bursting crackers. She underwent emergency surgery for lens removal due to severe injury to the lens and received a sutured IOL, which was specific for such cases. After 1 month, when the child came for follow up, it was found that there was a decenteration of the IOL. The parents had noted the child's difficulty in performing activities using the right eye. Under general anaesthesia, Agarwal removed the already existing IOL and placed a new IOL using the Glued IOL technique.
Indication Glued IOL surgery can be done both as a primary and as a secondary procedure in cases where the lens capsule is deficient or absent. As a primary procedure it can be done in all cases of intraoperative posterior capsule rupture. It can also be done in all cases of subluxation or dislocation of the lens, such as in Marfan syndrome, traumatic dislocation of lens, etc. As a secondary procedure it can be done in all the aphakic cases or as a part of an IOL exchange, following an anterior chamber IOL, or subluxated or dislocated IOL.
Fibrin glue Fibrin glue has been used previously, in various medical specialties, as a hemostatic agent to arrest bleeding, seal tissues, and as an adjunct to wound healing. It is available in a sealed pack that contains freeze-dried human fibrinogen (20 mg/0.5 ml), freeze-dried human thrombin (250 IU/0.5 ml), aprotinin solution (1,500 KIU in 0.5 ml), one ampoule of sterile water, four 21-gauge needles, two 20-gauge blunt application needles, an applicator with two mixing chambers, and one plunger guide. Preparation of glue: The vials are placed in a water bath which is preheated to 37 degrees for 2 to 3 minutes. 0.5 cc of distilled water is then added to the thrombin vial, and the aprotinin is mixed with fibrinogen. Each component is then placed in a separate syringe with a 26-gauge needle attached.
Surgical technique
The glued IOL technique consists of making two partial-thickness, approximately 2.5 mm by 2.5 mm, scleral flaps exactly 180° apart, followed by a sclerotomy with a 20-gauge needle 1 mm from the limbus. A 23-gauge vitrectomy cutter is introduced from the sclerotomy site, and a thorough vitrectomy is done to remove all the vitreous tractions. A corneal tunnel is fashioned, then a 23-gauge glued-IOL forceps is passed through the sclerotomy site, and the tip of the leading haptic of the IOL is grasped, which is then externalized and brought out onto the ocular surface (Fig 3). Similarly the trailing haptic is then externalized using the "handshake technique". Scleral pockets are made at the edge of the flap with a 26-gauge needle just parallel to the sclerotomy site, into which the two haptics are then tucked for additional stability (Fig 4). The scleral flaps are then glued back into place using biological glue. The IOLs that can be used are the three-piece foldable IOLs with slightly firm haptics, or a three-piece non-foldable IOL. The glue is then used to seal the conjunctival closure.
Vertical glued IOL The concept of performing a "vertical glued IOL" was first suggested by Jeevan Ladi. The vertical corneal diameter is always less than the horizontal diameter. In cases of large eyes, the least corneal diameter (i.e. at 6 o'clock and 9 o'clock) along the vertical axis can be chosen for making the scleral flaps. The IOLs currently available in the market are 13 mm in length. Choosing the least corneal diameter allows for extra length of the haptic available for tucking, and so gives extra stability. Advantages:
Comfortable temporal seating. Vortex veins are not disturbed. So, there is less bleeding. The flaps are hidden beneath the lid margin in the fornices, which gives a better appearance. Extra length of the haptic is available for tucking, which gives more stability to the IOL. According to some studies by Steven Safran, it is essential to state that the diameter of the ciliary sulcus and the corneal horizontal white-white diameter may not co-relate exactly; and it has been suggested that the surgeon can go ahead with horizontal placement of haptics rather than orienting them vertically.
Modifications in glued IOL surgery No-Assistant technique – This technique works on the principle of vector forces and was first performed by Priya Narang. In this technique, after the externalization of the leading haptic, the trailing haptic is flexed beyond the pupillary plane, towards the 6 o'clock position. This reverses the direction of vector forces and causes the leading haptic to extrude more from the previous sclerotomy site, thereby preventing haptic slippage and its subsequent complications. Plugging Silicon Tires of Iris Hooks – This technique was developed by George Beiko and Roger Steinert, wherein the silicon tires of the iris hooks are plugged to the leading haptic, to prevent its accidental slippage. Steven Safran developed the micro-bulldog technique for the same purpose. Y-Fixation technique – This technique was developed by Ohta Toshihiko, et al., wherein a Y-shaped incision is made, in the sclera, that eliminates the need to make a scleral flap. Mckee Yuri, Francis Price, et al., modified the scleral flap-making by lifting only two edges of the flap and keeping the flap adherent at the point of haptic enclavation.
Handshake technique
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