Fig. 1
Partial overlap
Rigid IOL
Polymethyl methacrylate has good structural memory and rigidity that resists optic decentration due to capsular fibrosis but it has a tendency to break if handled roughly.
Technique of IOL Placement in bag
The IOL placement can be done under viscoelastics, under continuous irrigation, or under an air bubble. The image displacement by the air bubble may confuse the trainee surgeons.
Technique of Leading Haptic Insertion
For insertion of a rigid IOL, hold the optic and trailing haptic with a lens holding forceps such as a McPherson forceps, and place the IOL into the eye, directing the leading haptic towards inside the capsular bag.
Next, to ensure that the optic is seated into the bag, partially release the grip over the optic and allow clockwise rotation of the optic in to the bag.
Once the optic and leading haptic are in the bag, the trailing haptic can be inserted into the bag in two ways.
Technique of Trailing Haptic Insertion
Using Forceps
Inject additional viscoelastic to inflate the capsular bag and anterior chamber. Hold the trailing haptic near the tip and move it to the 3 o’ clock position by folding the haptic over the optic. The haptic is depressed and released below the capsular margin (Fig. 2a–h). This is accomplished by the surgeon abducting the arm and pronating the forearm more while placing the haptic in to the bag. This maneuver is more suitable for a multipiece IOL.
Fig. 2a–h
IOL placement using forceps
Using Sinskey Hook
This step can be done through the main tunnel or through the sideport. If maneuvering through the main tunnel, one has to be aware that viscoelastics may leak out which can lead to a shallow anterior chamber.
IOLs with a dialing hole can easily be dialed in to the bag by placing sinskey hook in the dialing hole and by rotating the IOL with a downward movement for 2–3 clock hours preferably from 3 o’clock to 6 o’clock hour (Fig. 3a–f).
Fig. 3a–f
IOL placement using sinskey book
IOLs without a dialing hole can also be dialed using sinskey hook. Here the sinskey hook is positioned at optic-haptic junction and rotated to 3 o’clock hour over the iris and then rotated with a downward movement aiming the optic-haptic junction to go under rhexis which will eventually take the whole haptic inside. Here the surgeon’s forearm position has to change from pronation to a little supination. Care should be taken to inflate the bag with viscoelastics so that the sinskey hook will not tear the posterior capsule.
Since, rigid non-foldable IOL placement (compared to preloaded foldable IOL) needs more manipulation and handling of the IOL, care should be taken to minimize the contamination of IOL by conjunctival flora.